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1
Al Shamsi, Khalid, and Louay N. Mohammad. "Estimating Optimum Compaction Level for Dense-Graded Hot-Mix Asphalt Mixtures." Journal of Engineering Research [TJER] 7, no. 1 (June 1, 2010): 11. http://dx.doi.org/10.24200/tjer.vol7iss1pp11-21.
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A critical step in the design of asphalt mixtures is laboratory compaction. Laboratory compaction should reflect field compaction and should produce mixtures that are economical and possess high structural stability. During the compaction process, asphalt mixtures are subjected to certain amount of compaction energy in order to achieve the required density. The Superpave volumetric mix design is based on compacting HMA mixtures to a specified compaction level described by the number of gyrations from the Superpave gyratory compactor (SGC). This level is termed Ndes and represents the required energy (based on the traffic level expected) to densify the mixture to a 4% air voids level. This paper re-examines the Superpave compaction requirements through extensive laboratory investigation of the response of a number of asphalt mixtures to the applied compaction energy. It also presents an alternative method to estimate the number of gyrations at which a mixture first reaches an optimum aggregate interlock and hence prevents overcompaction problems that might result in unstable aggregate structures or dry asphalt mixtures. A total of 12 HMA mixtures were studied. During compaction, force measurement was made using the pressure distribution analyzer (PDA). The compaction characteristics of the mixtures were analyzed using data from the PDA and the traditional Superpave Gyratory Compactor (SGC) results.
2
He, Shi Wen. "Warm Compacting Behavior of Pure Titanium Powders." Advanced Materials Research 189-193 (February 2011): 2775–79. http://dx.doi.org/10.4028/www.scientific.net/amr.189-193.2775.
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Warm compacting behaviors of pure titanium powders were studied. The results show that warm compaction can be applied to titanium powders. The green densities obtained through warm compaction are generally higher than obtained through cold compaction at the same pressure. The optimal warm compacting temperature is about 140 . At the compacting pressure of 500 Mpa, the ejection force of titanium powders through warm compaction is 32.4% lower than through cold compaction. At the same pressure, the effective compression force through warm compaction is bigger than one through cold compaction. In addition, the densification mechanism of warm compaction was discussed.
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Karimov, M. S., T. U. Usmanov, Z. Sh Sharipov, and N. K. Usmanov. "Experimental research results on the erosion study of the temporary irrigating canal dam with pouring water and the establishment of the size of the dam compactor’s operating body." IOP Conference Series: Earth and Environmental Science 1043, no. 1 (June 1, 2022): 012040. http://dx.doi.org/10.1088/1755-1315/1043/1/012040.
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Abstract Research work has been carried out for several years in order to mechanize the technological process of dams' compaction and the development of a dam compactor. As a result of the experiments, the design of the dam compactor and the types of operating bodies were selected, the main optimal dimensions of the dam compactor were determined and mathematically analyzed. It was revealed that the main parameters of the dam compactor affecting the compaction process of temporary irrigating canal dams are cone roller diameter, length and width of the plate compactor, and the angle of dam nip. These parameters have been substantiated by theoretical and experimental studies. The optimal values of these parameters were determined by the mathematical planning of the experiment; below are the limits, as well as the variation levels of these factors. Based on the results obtained, an improved dam compactor was manufactured, and experimental studies were conducted in the field. At the same time, an increase in productivity relative to existing methods has been achieved and the compaction index has been brought to the required value. The mathematical model of the research object is the response function of an equation linking optimization parameters with controlled factors. The hypothesis of variance uniformity in the same non-repeated experiments was tested using the Cochran's test, and the significance of the regression coefficients was determined by the Student's criterion. The adequacy of the process model was checked by the Fisher criterion. After processing the experimental data and evaluating the coefficients' significance, regression equations describing the dam compaction process by the dam height and the compaction degree of the temporary irrigating canal dam were obtained. The main dimensions of compacting operating bodies of the dam compactor were selected.
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Maryoto, Agus. "Proposed concrete compaction method using an electrical internal vibrator: a review of compaction standard for concrete in laboratory according to SNI 2493:2011." MATEC Web of Conferences 195 (2018): 01003. http://dx.doi.org/10.1051/matecconf/201819501003.
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SNI 2493:2011 is the Indonesian National Standard containing the procedures for the manufacture and maintenance of concrete specimens in the laboratory. This standard regulates the way that compaction of compressive specimens is performed using internal vibrators in addition to manual compaction. Unfortunately, the amount and duration of vibrator compaction using an internal vibrator are not specified in the standard. This study examines the effect of vibrator duration when using an internal vibrator to compact concrete compressive strength specimens. The specimens used are of cylinders with diameter 15 cm and height 30 cm. 30 specimens were formed by each of the three concrete compaction methods used. The first type is where concrete is compacted manually by a tamping rod, 25 times each layer. The tamping rod is of 16 mm diameter and 62 cm height. The second type is compaction is by using internal vibrator, with 3 compactions per layer, each for 2 seconds. The third type also uses the internal vibrator, except the duration of each compaction is for 5 seconds. The results of compressive strength tests show that the compressive strength of the concrete compacted with the internal vibrator is about 10% higher than when manually compacting the concrete using a tamping rod. This proposed compaction of concrete by using an internal vibrator can be used as an alternative to manual compaction in the manufacture of concrete compressive strength specimens.
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Jia, Xiaoyang, Wei Hu, Pawel Polaczyk, Hongren Gong, and Baoshan Huang. "Comparative Evaluation of Compacting Process for Base Materials using Lab Compaction Methods." Transportation Research Record: Journal of the Transportation Research Board 2673, no. 4 (March 22, 2019): 558–67. http://dx.doi.org/10.1177/0361198119837953.
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Precise characterization of the compactability of aggregates and soils in the laboratory has always been a challenge to pavement technologists. The present study investigated compactability of aggregates and soils through the comparison of three laboratory compaction methods, the Superpave Gyratory Compactor, the Marshall impacting hammer, and a vibratory compacting machine. Accelerometers were attached to the Marshall impacting hammer and a laboratory scale vibratory compactor to capture the dynamic response of soils and aggregates during compaction. The results from this comparative experiment indicated that there was a consistent relationship between the stiffness of soils and aggregates and the dynamic responses from impaction and vibration, which can be used to better characterize the compactability of different paving materials through laboratory testing.
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Hou, Jing Ru, and Li Jun Zhao. "Effect of Different Compaction Methods on Bridge Pavement." Advanced Materials Research 671-674 (March 2013): 1073–77. http://dx.doi.org/10.4028/www.scientific.net/amr.671-674.1073.
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In order to analyze the influence of different compaction methods on bridge deck vibration and bridge pavement compaction quality, the field test and laboratory test of oscillating compaction and vibrating compaction were carried out. The results demonstrated bridge deck vibration caused by the intrinsic exciting force of compactor contributed to vibrating compaction. On the pattern of oscillating compaction, the disturbance of bridge deck due to the exciting force of compactor is the main factor to induce bridge vibration. Furthermore, the vibration acceleration and amplitude in lateral, longitudinal and vertical direction, oscillating compaction are much smaller than that of vibrating compaction. Compared with vibrating compaction, the rolling efficiency of oscillating compaction is obviously higher and the final compaction degree also is much higher. Besides that, phenomenon of crushing the coarse aggregate is exists in the compaction construction, in which the effect of vibrating compaction on crushing the coarse aggregate is more obvious than oscillating compaction, and the range of crushing the coarse aggregate caused by vibratory compaction is larger than oscillating compaction.
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Sarkar, Subhadeep, Dimitris Staratzis, Ziehen Zhu, and Manos Athanassoulis. "Constructing and analyzing the LSM compaction design space." Proceedings of the VLDB Endowment 14, no. 11 (July 2021): 2216–29. http://dx.doi.org/10.14778/3476249.3476274.
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Log-structured merge (LSM) trees offer efficient ingestion by appending incoming data, and thus, are widely used as the storage layer of production NoSQL data stores. To enable competitive read performance, LSM-trees periodically re-organize data to form a tree with levels of exponentially increasing capacity, through iterative compactions. Compactions fundamentally influence the performance of an LSM-engine in terms of write amplification, write throughput, point and range lookup performance, space amplification, and delete performance. Hence, choosing the appropriate compaction strategy is crucial and, at the same time, hard as the LSM-compaction design space is vast, largely unexplored, and has not been formally defined in the literature. As a result, most LSM-based engines use a fixed compaction strategy, typically hand-picked by an engineer, which decides how and when to compact data. In this paper, we present the design space of LSM-compactions, and evaluate state-of-the-art compaction strategies with respect to key performance metrics. Toward this goal, our first contribution is to introduce a set of four design primitives that can formally define any compaction strategy: (i) the compaction trigger, (ii) the data layout, (iii) the compaction granularity, and (iv) the data movement policy. Together, these primitives can synthesize both existing and completely new compaction strategies. Our second contribution is to experimentally analyze 10 compaction strategies. We present 12 observations and 7 high-level takeaway messages, which show how LSM systems can navigate the compaction design space.
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Iwański, Marek, Anna Chomicz-Kowalska, Piotr Ramiączek, Krzysztof Maciejewski, and Mateusz Iwański. "The influence of laboratory compaction methods on the physical and mechanical properties of foamed bitumen recycled mixes." Budownictwo i Architektura 13, no. 1 (March 11, 2014): 053–62. http://dx.doi.org/10.35784/bud-arch.1924.
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This study attempts to evaluate the influence of two advisable methods for compacting laboratory specimens of road base recycled mixes with foamed bitumen (MCAS) and bitumen emulsion (MCE). The obligatory regulations for this technology permit fabrication of the specimens using either an impact Marshall compactor or a static hydraulic press. The research showed that the compaction method influenced both the physical and mechanical properties of samples regardless of the type of bitumen binder. What is more, the structure of the material changed after the impact compaction process, which manifested in fact that many of the aggregate particles were crushed in its course. Better strength and resistance to moisture damage was observed in samples prepared in the hydraulic press. This was associated with lower void contents obtained in this compaction method.
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Shen, Pei Hui. "Hysteresis Modeling and Analysis for Dynamic Compaction." Advanced Materials Research 1037 (October 2014): 53–56. http://dx.doi.org/10.4028/www.scientific.net/amr.1037.53.
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The soil compactor is one of the most important construction machineries which play an significant role during our economic development. And the complicated nonlinear characteristic of equipment-material system is an interesting field in recent theoretical and applied investigations. According to experimental datum, a nonlinear model derived from piecewise linear was used to describe the hysteretic behavior of soil material during compaction. Through choosing proper model parameters, the nonlinear dynamic characteristics are commendably controlled which could represent different compacting stages. Furthermore, the series phase diagram and Poincare section were obtained by simulation. The hysteretic characteristics might be incarnating from periodic vibration to chaotic vibration. Further research proved that reducing the angular frequency of rotation may bring the chaotic vibration coming back to periodic vibration, which provided a good assistance for further study on hysteretic character of soil compaction and man-machine engineering on vibratory compacting system.
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Talaśka, Krzysztof, Dominik Wojtkowiak, Ireneusz Malujda, and Krzysztof Wałęsa. "Testing of a force sensor used to measure the briquetting process parameters of lignocellulosic materials." MATEC Web of Conferences 254 (2019): 05012. http://dx.doi.org/10.1051/matecconf/201925405012.
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The study presents a control and measurement system for the drive parameters of screw compactor machine with open working chamber for shredded materials. The study demonstrates the construction and working principle of the force sensor for measuring the axial force at the compacting screw. The calibration method for the measuring system was presented together with example measurement results for compaction of broken up rye straw, oat straw and hay. The study results were analyzed for feasibility of use for the compaction of materials with specific thermomechanical properties. The conclusion presents the possible forms of application of the established solution in mass production.
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Yang, Li Ying, and Yi Qiu Tan. "Compacting Properties of Zeolite Based Warm Asphalt Mixture." Advanced Engineering Forum 5 (July 2012): 299–304. http://dx.doi.org/10.4028/www.scientific.net/aef.5.299.
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Warm asphalt mixture develops rapidly throughout the world in recent years. Zeolite based warm mix is one of the warm mixtures. In this paper, seven kinds of zeolites including six natural zeolites and one synthetic zeolite are selected. As warm mix additives, their physical properties such as density, water content and pore arrangements are tested respectively. To evaluate the compacting properties of zeolites based warm asphalt mixture, AC-20 mixture is designed and compaction is conducted. It shows that zeolites can reduce the compacting temperature for both Marshall and gyratory compaction. Temperature is the main factors which influence the compaction effect. Type of zeolite affects compaction to some extent. Marshall compaction is more sensitive to zeolite than gyratory compaction.
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Talaśka, Krzysztof, Dominik Wojtkowiak, Ireneusz Malujda, and Krzysztof Wałęsa. "Testing of a torque sensor used to measure the parameters of the briquetting process of lignocellulosic materials." MATEC Web of Conferences 254 (2019): 05013. http://dx.doi.org/10.1051/matecconf/201925405013.
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The study presents a control and measurement system for the drive parameters of screw compactor machine with open working chamber for shredded materials. The study demonstrates the construction and working principle of the torque sensor for measuring the torque of the motor driving the compacting screw. The calibration method for the measuring system was presented together with example measurement results for compaction of broken up rye straw, oat straw and hay. The study results were analyzed for feasibility of use for the compaction of materials with specific thermomechanical properties. The conclusion presents the possible forms of application of the established solution in mass production.
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Peterson, Robert L., Kamyar C. Mahboub, R. Michael Anderson, Eyad Masad, and Laith Tashman. "Superpave® Laboratory Compaction Versus Field Compaction." Transportation Research Record: Journal of the Transportation Research Board 1832, no. 1 (January 2003): 201–8. http://dx.doi.org/10.3141/1832-24.
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Laboratory compaction is an important part of asphalt mix design. For the mix design process to be effective, laboratory compaction must adequately simulate field compaction. In this study mechanical properties measured with the Superpave® shear tester were used to evaluate field compaction and laboratory compaction. The field compaction consisted of three test sections with different compaction patterns. The laboratory compaction used the Superpave gyratory compactor with adjustments to several parameters. Results of this study indicate that current gyratory protocol produces specimens with significantly different mechanical properties than those of field cores produced with the same material and compacted to the same air voids. Results also show that adjustments to certain parameters of the gyratory can produce specimens that better simulate the mechanical properties of pavement cores.
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Cross, Stephen A. "Determination of Superpave® Gyratory Compactor Design Compactive Effort for Cold In-Place Recycled Mixtures." Transportation Research Record: Journal of the Transportation Research Board 1819, no. 1 (January 2003): 152–60. http://dx.doi.org/10.3141/1819b-19.
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Cold in-place recycling (CIR) is a viable pavement rehabilitation technique that recycles 100% of the reclaimed asphalt pavement (RAP) in place, without the addition of heat. One of the barriers to the use of CIR has been the lack of a suitable mixture design procedure. Researchers at the University of Rhode Island have shown that Superpave® mix design technology is applicable to CIR mixtures if the mix design compactive effort [number of compaction revolutions or gyrations ( Ndesign)] can be established for the Superpave gyratory compactor (SGC). The two objectives of the present project were to determine the mix design compactive effort ( Ndesign) with the SGC required to match the field densities of CIR mixtures and to evaluate the effect of sample compaction before and after breaking of the emulsion on the Ndesign compactive effort. RAPs from seven CIR projects were obtained, as was asphalt emulsion from each project. Samples were compacted with the SGC by use of the mix water and emulsion content from the field. The change in density with the number of compaction revolutions was monitored, and the Ndesign required to match the field density was determined. The effects of RAP physical properties, such as RAP gradation, the percentage of flat and elongated particles, aggregate gradation, and angularity, on Ndesign were evaluated. RAP shape, as measured by the percentage of flaky pieces, was found to influence the compacted field density. The Ndesign compactive effort for CIR mix design was also established.
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Parente, Manuel, and António Gomes Correia. "Compaction Management: Results of a Demonstration Project." Advanced Materials Research 779-780 (September 2013): 1697–700. http://dx.doi.org/10.4028/www.scientific.net/amr.779-780.1697.
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Compaction management, also referred to as intelligent compaction (IC), is a real time automatic operation adjustment and continuous compaction control technology of soils or asphalt layers. It is essentially a technology for optimization and evaluation of the compaction process, being capable of adjusting the compaction energy applied to the material, increasing or decreasing compaction efficiency in the necessary areas according to an acceptance target value, thus attaining maximum stiffness, while preventing overcompaction and minimizing the total number of passes. This study seeks to assess in a case study the IC performance, in comparison with conventional compaction methods in terms of efficiency in compaction of a sandy soil. For this purpose, a specific experimental section was carried out in which the performance of an IC compactor was compared with a conventional heavier class compactor. Data was obtained and analysed by the IC continuous information, as well as by the application of several different conventional compaction control tests and methods. Results show that the IC technology presents a superior performance, as well as various advantages when compared to conventional compactors.
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Li, Bo, Jian Xun Liu, and Xiu Li Su. "Effects of Compaction Method and Temperature on Warm Mix Asphalt." Advanced Materials Research 255-260 (May 2011): 3185–89. http://dx.doi.org/10.4028/www.scientific.net/amr.255-260.3185.
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A laboratory investigation was carried out on the volumetric properties of WMA fabricated using the Superpave gyratory compactor (SGC) and the Marshall compactor as a function of compaction temperature. The volumetric properties were obtained and analyzed at the six compaction temperatures 170°C,150°C,130°C,110°C,100°C,90°C. The results show that: Evotherm® can improved the compatibility of the mixtures; Warm Mix Asphalt is sensitivity to the temperature when the compaction method is Marshall; the method of SGC is conducive to dense asphalt pavement for WMA; the best compaction temperature of WMA is not lower than 125°C; the compaction temperature can decreased more than 20°C for WMA comparison with the HMA.
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O’Donnell, T. P., and P. S. Steif. "Elastic-Plastic Compaction of a Two-Dimensional Assemblage of Particles." Journal of Engineering Materials and Technology 111, no. 4 (October 1, 1989): 404–8. http://dx.doi.org/10.1115/1.3226487.
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The influence of pore shape on the porosity-pressure behavior of powders undergoing compaction is studied theoretically and numerically. Idealized two-dimensional models are used to compare the compression of circular pores, representing elevated temperature compaction, with cusp-shaped pores typically associated with cold compaction. An attempt is made to correlate porosity-pressure response with a logarithmic relation proven useful in the characterization of experimental compactions. A preliminary investigation on the effects of introducing a macroscopic shear into the compaction process is conducted.
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Xiao, Zhi Yu, M. Y. Ke, Wei Ping Chen, D. H. Ni, and Yuan Yuan Li. "A Study on Warm Compacting Behaviors of 316L Stainless Steel Powder." Materials Science Forum 471-472 (December 2004): 443–47. http://dx.doi.org/10.4028/www.scientific.net/msf.471-472.443.
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The application of warm compaction in stainless steel powders has not been formally reported by now. In this paper, the warm compacting behavior of 316L stainless steel powders had been studied. Results showed that warm compaction was effective in improving the green density and strength of 316L stainless steel powders. Under the compacting pressure of 800 MPa, warm compacted density was 0.20 g/cm3 higher than cold compacted one, and green strength was 52% higher. The optimum warm compacting temperature was 110±10°C. With die wall lubricated warm compaction, the internal lubricant content can be reduced by 0.5 wt%.
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Jiang, Shijia, Hao Yu, and Liantong Mo. "Crushing Characteristics of Coarse Aggregates for Asphalt Mixtures under Simulated Laboratory Compaction Loads and Repeated Traffic Loads." Materials 15, no. 17 (August 25, 2022): 5865. http://dx.doi.org/10.3390/ma15175865.
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The crushing characteristics of coarse aggregates for asphalt concrete were investigated under static and dynamic aggregate crushing value tests (ACVTs). The effect of various compaction loads was also examined by using a Marshall hammer, gyratory compactor and steel roller. Six types of coarse aggregates were tested, including basalt aggregate, steel slag, limestone aggregate, marble aggregate, recycled concrete aggregate and slightly weathered limestone aggregate. Test results indicate that static ACVT failed to reflect the crushing behavior of coarse aggregates under traditional traffic and compaction loads. The type of aggregate strongly influenced the crushing resistance, independent of type of load. The compaction loads simulated by using a Marshall hammer, gyratory compactor and steel roller resulted in a high aggregate breakage ratio and can distinguish the coarse aggregates with high crushing susceptibility. The crushing resistance was evaluated by using various crushing parameters and the corresponding critical value of these parameters was established. Gyratory compactor compaction resulted in more serious aggregate crushing when compared to Marshall hammer and steel roller compaction. Finite element modelling results on roller compaction and Marshall hammer compaction are in agreement with the aggregate crushing results. The aggregate crushing mechanism was found to be controlled by the fracture mode; the contribution of the attrition and abrasion modes was relatively small. When coarse aggregates with low crushing resistance are considered for the use for asphalt mixture, proper compaction is proved to be vital to prevent excessive aggregate breakage during mixture preparation and construction.
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Xiao, Zhi Yu, Tungwai Leo Ngai, and Yuan Yuan Li. "Investigation on the Densification Mechanism of Warm Compaction." Materials Science Forum 539-543 (March 2007): 2699–705. http://dx.doi.org/10.4028/www.scientific.net/msf.539-543.2699.
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Warm compaction is a low cost process to make high density and high performance iron base powder metallurgy parts. Based on results obtained from the dynamic compacting curve, ejection force curve, X-ray diffraction, micro-hardness of iron powder, friction condition and lubricant properties, densification mechanism of warm compaction can be drawn. In the initial stage, the rearrangement of powder particles is the main factor. It contributes more in the densification of warm compaction than that in cold compaction. However, in the later stage, the plastic deformation of powder particles is the primary factor. The increase in plasticity at high temperature can harmonize the secondary rearrangement of powder particles. During the compaction, the polymer lubricant has great contribution to the densification of the powder, since it improves the lubricating condition and effectively decreases the friction in the forming process and thus enhances the compact density. The dynamic compacting curve of warm compaction can be divided into three phases. The first is the particle rearrangement dominant phase; the percentage of particle rearrangement in warm compaction is higher than that in cold compaction by 15-31%. The second is the elastic deformation and plastic deformation dominant phase. The third is the plastic deformation dominant phase. The study of the powder densification mechanism can direct engineers in designing and producing warm compaction powders for high density parts.
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Zhou, Hao, Yongjian Guo, Qiang Xu, Guixia Zhang, and Zhen Wang. "Study on Vibration Compaction Energy of Basement Material." Coatings 12, no. 10 (October 7, 2022): 1495. http://dx.doi.org/10.3390/coatings12101495.
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In order to confirm the vibrate compaction energy, the indoor vibration compaction was conducted. Indoor vibration compactor was used to compact skeleton dense cement stabilized aggregate. The acceleration and displacement of the indenter and compaction pressure during the compaction process were measured. The bounce model and the hysteresis curve based on measurement parameters were used to calculate the compaction energy. Three vibration compaction energy were affirmed as: energy of the machinery itself (Eself), energy transmitted from machinery to compacted material (Et) and energy stored by compacted materials (Es). The energy Eself was about 40 J (joule). During each compaction process, energy Et was only 1–1.8 J. In a one-minute compaction process, 2500 J of energy would be transmitted, but only 38 J could be stored by the compacted material.
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Collins, Ronald, Donald Watson, Andrew Johnson, and Yiping (Peter) Wu. "Effect of Aggregate Degradation on Specimens Compacted by Superpave Gyratory Compactor." Transportation Research Record: Journal of the Transportation Research Board 1590, no. 1 (January 1997): 1–9. http://dx.doi.org/10.3141/1590-01.
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Aggregate degradation during gyratory compaction may cause changes in the original gradation of the aggregate, and it may also affect volumetric requirements for Superpave Level I mix design. The effect of aggregate degradation on the design gradation and final volumetric properties of the asphalt mix compacted by the Superpave gyratory and Astec vibratory compactors was evaluated. Because vibratory compaction is an alternative compaction method that simulates field compaction, a vibratory compactor developed by Astec Industries, Inc., was used for comparison with the Superpave gyratory compactor. Aggregates with high and low Los Angeles abrasion losses were used to evaluate the effect of aggregate toughness or abrasion resistance on gradation change and volumetric properties. The changes in the amount of material passing the 0.075-mm sieve due to aggregate degradation during compaction were not significant enough to prevent specimens from meeting dust proportion requirements, regardless of whether low-or high-abrasion loss aggregates were used. A mix containing high-abrasion aggregate was less likely to meet restricted zone requirements than a mix using low-abrasion aggregate after degradation resulting from compaction.
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Ahmed, Hassan, and Jouni Punkki. "Surface Bubbles Emergence as an Indicator for Optimal Concrete Compaction." Materials 17, no. 10 (May 13, 2024): 2306. http://dx.doi.org/10.3390/ma17102306.
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Compaction quality significantly influences the strength and durability of concrete in structures. Under-compacting can retain entrapped air, reducing strength, while over-compacting can lead to segregation, creating local variances in strength distribution and modulus of elasticity in the concrete structure. This study examines the widely adopted concept that compaction is optimal when bubbles cease to emerge on the concrete surface. We recorded the surface activity of six comparable concrete specimens during the compaction process using a 4K video camera. Four specimens were compacted using a table vibrator and two with a poker vibrator. From the video frames, we isolated the bubbles for analysis, employing digital image processing techniques to distinguish newly risen bubbles per frame. It was found that the bubbles continuously rose to the surface in all specimens throughout the compaction process, suggesting a need for extended compaction, with some specimens showing a slow in the rate of the bubbles’ emergence. However, upon examining the segregation levels, it was discovered that all the specimens were segregated, some severely, despite the continued bubble emergence. These findings undermine the reliability of using bubble emergence as a principle to stop compaction and support the need for developing online measurement tools for evaluating compaction quality.
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Voicu, Gheorghe, Mircea Lazea, Gabriel-Alexandru Constantin, Elena-Madalina Stefan, and Mariana-Gabriela Munteanu. "Finite element analysis of the compaction plate from a garbage truck." E3S Web of Conferences 180 (2020): 04006. http://dx.doi.org/10.1051/e3sconf/202018004006.
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Vehicles that collect and transport household waste are equipped with complex systems that perform the loading of the waste from the stationary collection containers, take over and pre-compact of material, compaction in the body of the structure and finally the landfill of the collected waste. Of all these operations, the compaction process is by far the most mechanically demanding. In this paper, the structural analysis of the compactor plate from a garbage truck is presented. In the first stage it was carried out parametric modelling of the assembly composed of compactor plate, counter pressure plate, the back of the garbage truck and to be compacted material. After assembly, the dynamic simulation of the compaction process in the garbage truck was performed, and the compaction mechanical stresses for the compactor plate were loaded in the Simulation module of the SolidWorks 2016 program. Here the finite element analysis was performed, resulting in the value and dispersion of the equivalent stresses (calculated by von Mises criterion), displacements and relative deformations of compactor plate from the analysed garbage truck.
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Gong, Xiangbing, Ziming Liu, Guoping Qian, and Zhiyang Liu. "Interlocking Evaluation of Mesoscopic Skeleton with the Compaction Degree of Hot-Mix Asphalt." Materials 16, no. 17 (August 28, 2023): 5879. http://dx.doi.org/10.3390/ma16175879.
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Asphalt mixtures are multi-phase composites composed of aggregates, bitumen, mineral powders, and voids, and various structures are intertwined during the compaction process. Most of the traditional research focuses on the macro-scale domain, and it is difficult to obtain the internal structure of asphalt mixture in different compaction processes. With the continuous development of digital image technology, the influence of the meso-structure of the asphalt mixture on the compaction quality of the asphalt mixture has become a new means to evaluate the performance of the asphalt mixture. In this paper, different numbers of compactions are selected to represent different stages in the compaction process, the digital images of specimens in different compaction stages are obtained by industrial CT scanning technology. Then, the images are processed and reconstructed in three dimensions using improved image segmentation methods, and the position characteristics and geometric information of coarse aggregate are obtained by combining the Oriented Bounding Box (OBB). The meso-response characteristics of the skeleton structure of the asphalt mixture during compaction were studied. The influence of the internal structure of the mixture on the compaction quality of the mixture was obtained, which is of great significance for the study of improving the durability of the pavement. The results show that the “effective coordination number” (the number of aggregate particles that can transmit force in the skeleton structure) is greatly related to the aggregate size. With the compaction process, the centroid of coarse aggregate in the upper layer of the specimen reflects the overall downward movement trend. The inclination angle of the aggregate spindle tends to be in the range of 80°~100°; the anisotropic amplitude of the xy plane increases, and the direction of the aggregate spindle becomes more and more consistent. With the increase in the number of rotational compactions, these four parameters showed obvious rules, indicating that this meso-characteristic index could well characterize the compaction quality of the asphalt mixture in the compaction process.
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Kim, Jinyoung, Sung-Yeol Lee, and Jin-woo Cho. "A Study on the Analysis of the Ground Compaction Effect According to the Roller Operation Method through CMV Analysis Using IC Rollers." Advances in Civil Engineering 2023 (October 25, 2023): 1–10. http://dx.doi.org/10.1155/2023/6589652.
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In road construction, the compaction process using vibratory rollers is essential to increase the ground stiffness in earthworks. There need to be clear standards regarding the operation of compaction rollers during compaction work. Various simple quality inspection techniques have been developed to check the stiffness of the ground, but plate load test and field density test are the most commonly used test methods to evaluate the degree of compaction during road construction. However, both inspection methods could be more efficient, as they cannot be performed in all sections due to time and cost. Additionally, in compaction work today, the worker will individually judge the number of compactions, thickness, speed, vibration etc. based on his or her own experience. This means that the quality of compaction varies depending on the worker. In this study, quality inspection results for all sections were obtained using an intelligent quality control system that employs an IC roller, a technology that is now commercially available. The effect of the operating conditions of the vibrating roller (roller compaction direction, compaction roller speed, and compaction roller vibration method) on the compaction quality was analyzed using the intelligent quality control value. Through our highway construction site tests, it was found that the speed of the compaction roller and the vibration method of the compaction roller affected the degree of compaction, but the direction of compaction did not. Therefore, if the compaction work is performed by adjusting the driving speed and vibration method of the vibrating roller according to the ground conditions, repetitive compaction work can be reduced, thereby reducing construction costs and lowering work time, which will achieve an improved work efficiency.
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Chen, Qun, and Yuzhi Li. "SGC Tests for Influence of Material Composition on Compaction Characteristic of Asphalt Mixtures." Scientific World Journal 2013 (2013): 1–10. http://dx.doi.org/10.1155/2013/735640.
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Compaction characteristic of the surface layer asphalt mixture (13-type gradation mixture) was studied using Superpave gyratory compactor (SGC) simulative compaction tests. Based on analysis of densification curve of gyratory compaction, influence rules of the contents of mineral aggregates of all sizes and asphalt on compaction characteristic of asphalt mixtures were obtained. SGC Tests show that, for the mixture with a bigger content of asphalt, its density increases faster, that there is an optimal amount of fine aggregates for optimal compaction and that an appropriate amount of mineral powder will improve workability of mixtures, but overmuch mineral powder will make mixtures dry and hard. Conclusions based on SGC tests can provide basis for how to adjust material composition for improving compaction performance of asphalt mixtures, and for the designed asphalt mixture, its compaction performance can be predicted through these conclusions, which also contributes to the choice of compaction schemes.
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Zeinali, Alireza, Phillip B. Blankenship, R. Michael Anderson, and Kamyar C. Mahboub. "Laboratory Investigation of Asphalt Pavements with Low Density and Recommendations to Prevent Density Deficiency." Advanced Materials Research 723 (August 2013): 128–35. http://dx.doi.org/10.4028/www.scientific.net/amr.723.128.
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In most USA asphalt construction projects the goal of compacting a hot-mix asphalt (HMA) layer is to achieve the optimum density which is 92% of the maximum specific gravity (Gmm) of the asphalt mixture. However, this level of density is not always achieved. This paper evaluates the effect of field compaction deficiencies on the HMA durability through laboratory testing. HMA samples were collected from construction sites in the United States. A series of laboratory tests were conducted to compare the performance of HMA mixtures at their actual in-place density as well as the desired density of 92% of Gmm. The statistical analysis on the results showed that the performance of the pavements could significantly improve by eliminating the deficiencies in their in-place densities. Moreover, the compactibility of the mixtures was investigated using the compaction data from the Superpave gyratory compactor. Compaction characteristics of the mixtures were compared to a control mixture, and the results showed that the shortage in the binder content of the mixtures could be a major factor which may have caused the density deficiencies. Furthermore, the effect of higher-than-optimum binder content was evaluated on the compactibility of the control mixture.
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Kurniawan, Eko, Nelvia Nelvia, and Wawan Wawan. "Phisycal And Chemical Properties And Nutrient Content (N, P, K, Mg, B, Cu And Zn ) In Oil Palm Leaf In Various Of Age After Compacting." JURNAL AGRONOMI TANAMAN TROPIKA (JUATIKA) 2, no. 2 (July 4, 2020): 86–100. http://dx.doi.org/10.36378/juatika.v2i2.508.
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Planting of oil palm in peatland has been limited by soil physical, chemical properties, and hydrology, that`s way needed improvement on those matters to increase the productivity of peat and oil palm in peat soil by compacting. The purpose of this compacting is to improve the soil's physical, chemical properties, and soil moisture. A sampling of soil, water, and leaf were done in consecutive block 5,4,3,2,1,0 year after compacting and of planting done 4 years 10 months, 3 years 9 months, 2 years 9 months, 1 year 10 months, 11 months and 2 months, control used in this trial are origin condition (forest). Increasing bulk density was found at compacting block with 30 cm depth from the surface with the lower in 2 years after compacting at 0.09 g/cm3 and highest 4 years after compacting 0.4 g/cm3. In-depth of 60 cm from surface was found no increasing the bulk density 3 years after compacting 0.0 g/cm3 and the highest on 5 years after compacting 0.3 g/cm3 compared to forest. Decreasing on permeability in-depth 30 cm at 4 years after compacting 7.47 cm/jam and close to forest permeability 51.11 cm/hour is 2 years 43.6 cm/hour. As represent rise capillary consistently water content ≥ 80% achieved at depth 20 cm of surfaces on all block. Compaction doesn't regard pH, C organic, basa's saturation, capacity exchange cation. On depth 30 cm P-total lower on s without compaction at 599.6 ppm and above 871.6 ppm on 5 yr than forest 585 ppm. P available most low 58.1 ppm happens on 4 yr afters is compacted and p available forest 53.9 ppm. Nutrient content B, Cu and Zn at soil not influenced by compaction. Fosfor (P) in water increases with added years after compaction lower at 39.1 mg/L in the block without compaction compare of forest that 40.8 mg/L. Leaf nutrient rate on compacted block on optimum until excess where N (2. 69 – 3.15 %) , P (0. 170 – 0.209 %) , K( 0. 952 – 1.11%) , Mg ( 0. 377 – 0.497%) , except on block without compacting K (0. 830 %) and Mg (0. 190%) at deficiency and 0 years afters compaction Mg leaf on level deficiency 0. 230%. Nutrient content of B, Cu and Zn at various level and not influenced by compacting.
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Phan, Truc, Meen-Wah Gui, and Thang Pham. "Finite element analysis of compaction load to investigate the stress-deformation behavior of soil geosynthetic composite mass: A case study." IOP Conference Series: Materials Science and Engineering 1289, no. 1 (August 1, 2023): 012105. http://dx.doi.org/10.1088/1757-899x/1289/1/012105.
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Abstract When building Soil Geosynthetic Composite (SGC) walls, fill compaction is normally carried out by operating a compactor in a general direction parallel to the wall face. In other words, a moving point or area load is often used to apply a compaction load on a newly installed soil lift. Pham (2009) and Wu and Pham (2010) demonstrated that the compaction-induced stress (CIS) caused by multiple passes of a compactor moving toward or away from a section can be calculated by taking into account the compaction load applied directly above the section under consideration using a simplified stress path proposed by Duncan and Seed (1986). Additionally, by simulating the compaction, the CIS due to fill compaction may be correctly assessed. The CIS resulting from fill compaction can also be accurately assessed by simulating the compaction load, such as by applying a distribution load on top of each backfill layer or a distribution load at the top and bottom of each soil layer, or by applying various widths of strip load to the top of each backfill layer. The objective of this study was to validate the numerical simulation of the compaction load to stress deformation behavior of SGC mass under operating stress conditions. In order to conduct the numerical analysis, data from both a full-scale instrumented SGC mass based on large-scale soil geosynthetic composite (SGC) experiments and a 6 m-high SGC (Pham, 2009) were employed. This study will examine a few SGC behavior parameters, including reinforcement strains, lateral displacements, and reinforcement strains. The objective of the FE modeling is to demonstrate the effect, emphasize the significance of the compaction conditions to the stress-deformation behavior of SGC mass, and validate the findings from the field-scale experiments and proposed model by Pham (2009) and Wu and Pham (2010).
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Chen, Xiang Yang, Heng Zhen Yan, and Xin Xi Liu. "Study on Engineering Characteristics of Highly Weathered Weak Rock." Advanced Materials Research 261-263 (May 2011): 1309–12. http://dx.doi.org/10.4028/www.scientific.net/amr.261-263.1309.
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When highly weathered weak rock used to fill embankment, compaction character and wetting deformation character are major evaluation indexes. Based on California Bearing Ratio (CBR) test for highly weathered weak rock under different compaction degree, it was shown that the value of CBR increased as the increase of compaction degree. By means of dry-wet double curve parallel tests and wetting deformation experiments of different compaction degree of highly weathered weak rock under complex stress, the results indicated that when the degree of compaction is 90%, under rather high deviatoric stress, wetting can not only generate high additional axial deformation, but also cause fairly high additional volumetric strain and partial strain. And wetting cause shear intensity of soil reducing. So increasing the compactions of subgrade filling is the important way to reduce wetting deformation and to enhance slope stability of subgrade.
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Gui, Meenwah, Truc Phan, and Thang Pham. "Impacts of Compaction Load and Procedure on Stress-Deformation Behaviors of a Soil Geosynthetic Composite (SGC) Mass—A Case Study." Applied Sciences 10, no. 18 (September 11, 2020): 6339. http://dx.doi.org/10.3390/app10186339.
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Fill compaction in the construction of Geosynthetic Reinforced Soil (GRS) mass is typically performed by operating a vibratory or roller compactor, which in turns imposed a compaction load in direction perpendicular to the wall face. The compaction process resulted in the development of the so-called compaction-induced stress (CIS), which may subsequently increase the stiffness and strength of the fill material. Compaction process is normally simulated using one of the following compaction procedures—(i) a uniformly distributed load acting on the top surface of each soil lift, (ii) a uniformly distributed load acting on the top and bottom surface of each soil lift, and (iii) a moving strip load with different width. Uncertainties such as compaction procedures, compaction and surcharge loads led to the disparity in studying the mechanism of GRS mass. This paper aimed to study the impact of compaction load, compaction procedure, surcharge load and CIS on the stress-deformation behavior of GRS mass via the simulation of a 2 m high Soil Geosynthetic Composite (SGC) mass and a 6 m high GRS mass. The results were examined in terms of reinforcement strains, wall lateral displacements, and net CIS. Results from the analysis show the important impacts of compaction conditions on the stress-deformation behavior of SGC mass and the CIS.
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Ouyang, Y., JJ Zeng, LG Li, and AKH Kwan. "Influence of concrete mix proportions on axial performance of concrete-filled steel tubes made with self-compacting concrete." Advances in Structural Engineering 23, no. 5 (November 1, 2019): 835–46. http://dx.doi.org/10.1177/1369433219884457.
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Self-compacting concrete is quite commonly used in concrete-filled steel tube structures, but the compaction level of the self-compacting concrete, that is, the percentage of volume occupied by materials other than air void, within the steel tube is seldom investigated. The authors are of the view that the concrete mix proportions of the self-compacting concrete may have significant effects on the compaction level of the self-compacting concrete, which will be quantified by the ‘compaction index’ proposed in this study and thus the performance of the concrete-filled steel tube. Moreover, the mix proportions would also influence the performance of the concrete-filled steel tube by affecting the aggregate–aggregate and aggregate–paste interactions of the concrete, albeit this important issue is rarely addressed in previous studies either. Herein, a pilot study is conducted to investigate the influences of the self-compacting concrete mix proportions on the axial performance of concrete-filled steel tube. Four groups of concrete-filled steel tube specimens made with different self-compacting concrete were tested, and the investigated concrete mix parameters included the paste volume, fine to coarse aggregate ratio, and 9.5–19.0 mm aggregate ratio. It was found that the compaction index of the self-compacting concrete is a key factor enabling the successful use of self-compacting concrete in concrete-filled steel tube. Moreover, the paste volume and aggregate proportions of the concrete mix have certain effects on the post-peak behaviour and ductility of concrete-filled steel tube.
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Wilczyński, Dominik, Krzysztof Talaśka, Dominik Wojtkowiak, Krzysztof Wałęsa, and Szymon Wojciechowski. "Selection of the Electric Drive for the Wood Waste Compacting Unit." Energies 15, no. 20 (October 11, 2022): 7488. http://dx.doi.org/10.3390/en15207488.
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This work presents the study of the compaction and unloading process wood post-production waste, i.e., oak sawdust. The sawdust was compacted employing the forces F = 5000, 10,000, 20,000, 30,000, 40,000 and 50,000 N. Each compacted sample was compressed so as to determine the force value Fc required for the destruction of the sample. For each compaction force, the coefficient of the friction value µ1 was determined for the sawdust–steel material pair, which was used in the construction of the sleeve and stamp compacting system employed in the study. The determined parameters of the compressive force Fc and the coefficient of friction µ1 as a function of the compaction force F enabled to determine the optimal process parameters. A proposed construction of the compacting unit with an electrical drive is provided in the following part of the work comprising a motor, gear wheels, cam and a compacting piston. The selection of the parameters for the compaction process and the drive is of key importance from the standpoint of its energy consumption, influencing the energy balance, i.e., the ratio of input process energy and the energy obtained from the manufactured briquette. For the purpose of selecting the drive system, a mathematical model was developed utilizing earlier results of experimental studies. This model enabled to determine the maximum torque value Ms necessary to drive the proposed compacting unit. As a result of the carried-out work, it was determined that the maximum compaction force F is not ideal, considering other process parameters and their influence on its performance, allowing to lower the maximum torque and power of the proposed compacting unit.
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Ke, Mei Yuan. "Warm Compacting Behaviors and Sintering Performance of 316L Stainless Steel Powder." Advanced Materials Research 538-541 (June 2012): 1088–91. http://dx.doi.org/10.4028/www.scientific.net/amr.538-541.1088.
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Warm compacting behavior and sintering performance of 316L stainless steel powders were studied. Results showed that green density and strength of samples made in warm compaction were much higher than that in cold compaction. Under pressure of 700MPa, green density and strength in warm compaction were 7.01 g•cm-3and 30.7MPa, which were higher than cold compaction by 0.19 g•cm-3and 10.7MPa. When sintered in hydrogen-nitrogen atmosphere for 60 minutes, sintered density, tensile strength and elongation all increased with the rise of sintering temperature. At 1300°C, Sintered density, tensile strength and elongation were 7.42 g•cm-3, 545MPa, 28.0%, respectively.
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Chen, Chia-Hsin, Yung-Kang Shen, and Sung-Chih Hsieh. "The investigation of gutta-percha temperature and compaction force change when using the vertical compaction of warm gutta-percha technique." Journal of Polymer Engineering 34, no. 3 (May 1, 2014): 219–23. http://dx.doi.org/10.1515/polyeng-2013-0211.
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Abstract The naturally occurring isoprene rubber component of gutta-percha has been used in dental root canal filling treatments for almost a hundred years owing to its stability and plasticity as a root canal filling material. The traditional warm gutta-percha vertical compaction technique is the major technique for warm gutta-percha root canal obturation. However, the relation between compaction force and temperature change in this technique is still unclear. The purposes of this study were to determine the ideal gutta-percha molding temperature for compaction and to evaluate single and double heating and compaction in the warm vertical compaction procedures using infrared thermography. Gutta-percha was placed in a digital dry bath incubator at temperatures ranging from 25°C to 62°C in order to analyze compaction forces using an Instron universal testing machine. Both single and double heating and compaction procedures were examined using an infrared thermograph model to monitor temperature change when performing the warm gutta-percha vertical compaction procedure. Our results demonstrate that 44–58°C is the ideal temperature to soften gutta-percha for excellent compaction. Heating and compacting gutta-percha twice at 3 mm from the apex can mold the gutta-percha completely.
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Yao, Junkai, Mao Yue, Hongsheng Ma, and Changwei Yang. "Wave Propagation Characteristics and Compaction Status of Subgrade during Vibratory Compaction." Sensors 23, no. 4 (February 15, 2023): 2183. http://dx.doi.org/10.3390/s23042183.
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Vibratory compaction status has a significant influence on the construction quality of subgrade engineering. This study carried out field experiments to study the propagation characteristics of the vertical vibration wave in the soil field along the traveling direction of the vibratory roller. The propagation coefficients of the peak acceleration at different positions and compacting rounds are compared in both the time and frequency domains. The compaction status is estimated in the form of dynamic modulus of deformation (Evd) obtained by plate load tests. The experiment results show that the propagation coefficient of peak acceleration is affected by the traveling speed, excitation amplitude, and frequency of the vibratory roller, as well as the compacting rounds. An exponential relationship between the wave amplitudes of the fundamental mode and higher-order modes is revealed. The amplitude of the fundamental wave is maximum at the speed of 3 km/h, whereas the amplitudes of higher-order waves have a maximum of 1.5 km/h. The influences of compaction rounds on the average value of Evd are also investigated to provide a practical reference for engineering construction.
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Marins, Araceli Ciotti de, José Miguel Reichert, Deonir Secco, Doglas Bassegio, and Daniela Trentin Nava. "Crambe grain yield affected by compaction degrees of an Oxisol." Research, Society and Development 11, no. 3 (February 15, 2022): e12111326500. http://dx.doi.org/10.33448/rsd-v11i3.26500.
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Crambe is a new crop that produces oil used for biodiesel production. Soil compaction in a no-tillage (NT) system is one of the main challenges for sustainable grain production in soil clay. The objective of this study was to evaluate the effect of compaction degree on crambe grain yield over two years. The levels of artificial compaction were generated using a roller compactor (0, 1, 3, and 5 passes) under a NT system. The experimental design was a strip block, and soil density and crambe grain yield were evaluated. The passes of the roller increased the density from 0.98 to 1.24 Mg m−3 in the 0–0.1 m layer, and 1.03 to 1.15 Mg m−3 in the 0.1–0.2 m layer. As a result, the compaction degree increased from 53% to 66% in the 0–0.1 m layer and 54% to 61% in the 0.1–0.2 m layer. Five passes of the roller compactor reduced the crambe grain yield by 41% and 9% in the first and second years, respectively, compared to the NT system without additional compaction. The crambe grain yield was reduced when the compaction degree reached 53%; therefore, crambe is not suitable for compacted soils.
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Chen, Jing Song, Lei Zeng, and Jian Yin. "Discrete Element Method (DEM) Analyses of Hot-Mix Asphalt (HMA) Mixtures Compaction and Internal Structure." Advanced Materials Research 639-640 (January 2013): 1287–94. http://dx.doi.org/10.4028/www.scientific.net/amr.639-640.1287.
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Asphalt mixture compaction is an important procedure of asphalt mixture construction and can significantly affect the performance of asphalt pavement. In this paper, an open source DEM code was applied to simulate the compaction of hot-mix asphalt (HMA) with the Superpave gyratory compactor. The asphalt mixture compaction process, air voids distribution, internal coarse aggregate structure, and the effect of CA ratio were investigated from a microscopic point of view. The analysis results show that DEM simulation is an economical and effective approach to the research of asphalt mixture compaction, and has tremendous potential for asphalt mixture design.
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Kai, Y., J. Hamada, M. Morioka, S. Yano, and J. Kuratsu. "Evaluation of the Stability of Small Ruptured Aneurysms with a Small Neck after Embolization with Guglielmi Detachable Coils." Interventional Neuroradiology 12, no. 1_suppl (January 2006): 91–96. http://dx.doi.org/10.1177/15910199060120s113.
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It is difficult to predict the compaction of Guglielmi detachable coils (GDC) after endovascular surgery for aneurysms. Therefore, we studied the relationship between the coil packing ratio and compaction in 62 patients with acute ruptured intracranial aneurysms that were small (<10 mm) had a small neck (<4 mm) and were coil-embolized with GDC-10. We recorded the maximum prospective coil length, L, as the length that correspond with the volume of packed coils occupying 30% of the aneurysmal volume. L was calculated as L (cm) = 0.3 × a × b × c and the coil packing ratio expressed as packed coil length/L × 100, where a, b, and c are the aneurysmal height, length, and width in mm, respectively. Angiographic follow-up studies were performed at three months and one and two years after endovascular surgery. Of the 62 patients, 16 (25.8%) manifested angiographic coil compaction (ten minor and six major compactions); the mean coil packing ratio was 51.9 ± 13.4%. The mean coil packing ratio in the other 46 patients was 80.5 ± 20.2% and the difference was statistically significant (p<0.01). In all six patients with major compaction the mean packing ratio was below 50%. We detected 93.8% of the compactions within 24 months of coil placement. In patients with small, necked aneurysms, the optimal coil packing ratio could be identified with the formula 0.3 × a × b × c. The probability of compaction was significantly higher when the coil packing ratio was under 50%. To detect coil compaction post-embolization, follow-up angiograms must be examined regularly for at least 24 months.
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Maulana, Rizky, and Abdul Kholiq. "METODE PELAKSANAAN OVERLAY REKONSTRUKSI PADA PROYEK CIKOWOAN – KADUT (REGULER) DI STA 1 + 700 s/d STA 2 + 286." SEMINAR TEKNOLOGI MAJALENGKA (STIMA) 7 (November 8, 2023): 259–73. http://dx.doi.org/10.31949/stima.v7i0.895.
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In terms of access to mobilization/demobilization and the location is very steep, the dump load is minimal due to poor access. Very high rainfall has resulted in further delays in the implementation of work. ACBC (Asphalt Concrete Binder Course) asphalt foundation and top layer or asphalt surface wear layer ACWC (Asphalt Wearing Course) for the material used, namely Asphalt Emulsion CSS -1 or SS -1 layer thickness (AC-BC) solid with a thickness of 0.6 cm with a loose thickness of 7.4 cm, the layer thickness (AC-WC) was solid with a thickness of 0.5 cm and a loose thickness of 6.4 cm. AC-WC compaction is divided into 3 parts, namely first compaction (breakdown rolling), second compaction (intermediate rolling), final compaction (final rolling). The first compaction is carried out when the temperature reaches 111 C to 102 C or about 0 – 10 minutes from the time the AC – WC is held. This ride uses a tandem roller with the number of tracks according to the trial compaction. The second compaction is carried out at a temperature of 102 C to 83 C or about 10-20 minutes since the AC-WC was held. This event uses a Pneumatic Roller with the number of passes according to trial compaction. The final compaction was carried out at a temperature of 83 C to 63 C or around 20-45 minutes since the AC-WC was held. This event uses a Pneumatic Tandem Roller with 12 to 15 passes. In the work of the Cikowoan – Kadut Road Improvement Reconstruction Project in Majalengka Regency, the tools used are Mini Excavators, Asphalt Tanks and assistive devices (asphalt sprayer), Dump trucks, Tandem combin rollers, Mini iron wheel compactor machines (baby roller), soil compactor machine.
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Zhang, Yu, and Bo Wei Sun. "Different CA Compaction Property of the Asphalt Mixture on the Bailey Method." Applied Mechanics and Materials 361-363 (August 2013): 1761–64. http://dx.doi.org/10.4028/www.scientific.net/amm.361-363.1761.
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This paper evalates the compaction property of the asphalt mixture through the densification curve of the Superpave Gyratory Compactor, introduces four factors such as CEI、TDI、k1、k2 to reflect the compaction property of the asphalt mixture under construction and traffic load, and analyses the compaction extent of the asphalt mixture with different CA.Based on the performance demand and the construction techniques,this paper gives reasonable range of the Bailey parameters CA.
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Zhang, De, Zhiqiang Cheng, Dajiang Geng, Shengjia Xie, and Tao Wang. "Experimental and Numerical Analysis on Mesoscale Mechanical Behavior of Coarse Aggregates in the Asphalt Mixture during Gyratory Compaction." Processes 10, no. 1 (December 27, 2021): 47. http://dx.doi.org/10.3390/pr10010047.
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Compaction is a critical step in asphalt pavement construction. The objective of this study is to analyze the mesoscale mechanical behaviors of coarse aggregates in asphalt mixtures during gyratory compaction through experiments and numerical simulation using the Discrete Element Method (DEM). A novel granular sensor (SmartRock) was embedded in an asphalt mixture specimen to collect compaction response data, including acceleration, stress, rotation angle and temperature. Moreover, the irregularly shaped coarse aggregates were regenerated in the DEM model, and numerical simulations were conducted to analyze the evolution of aggregate interaction characteristics. The findings are as follows: (1) the measured contact stress between particles changes periodically during gyratory compaction, and the amplitude of stress tends to be stable with the increase of compaction cycles; (2) the contact stress of particles is influenced by the shape of aggregates: flat-shaped particles are subjected to greater stress than angular, fractured or elongated particles; (3) the proportion of strong contacts among particles is high in the initial gyratory compaction stage, then decreases as the number of gyratory compactions grows, the contacts among particles tending to homogenize; (4) during initial gyratory compactions, the normal contact forces form a vertical distribution due to the aggregates’ gravity accumulation. The isotropic distribution of contact forces increases locally in the loading direction along the axis with a calibrated internal angle orientation (1.25°) in the earlier cyclic loading stage, then the local strong contacts decrease in the later stage, while the strength of the force chains in other directions increase. The anisotropy of aggregate contact force networks tends to weaken. In other words, kneading and shearing action during gyratory compaction have a positive impact on the homogenization and isotropy of asphalt mixture contact forces.
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Nugraha, Andrias Suhendra, Paulus Pramono Rahardjo, and Imam Achmad Sadisun. "Comparison of the Number of Compactor Passes and the Constrained Modulus of a Compacted Volcanic Soil." Journal of Mechanical, Civil and Industrial Engineering 4, no. 1 (February 13, 2023): 17–27. http://dx.doi.org/10.32996/jmcie.2023.4.1.3.
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Volcanic soil is often used as fill material in road embankment construction in Java island-Indonesia. An understanding of the engineering properties of compacted volcanic soils is needed, especially during the preliminary design phase and during the detailed design phase of the road embankment. Carrying out a field compaction trial test will significantly assist in the design of the compaction process of the road embankment construction. Selecting the correct number of passes from the compactor and the engineering properties of compacted volcanic soils can be obtained from field compaction trial tests. Constrained modulus is one of the engineering properties that can indicate the stiffness of the fill material used in a road embankment. This study aims to determine the constrained modulus of compacted volcanic soil and compare it to the number of passes of a compactor from the field compaction trial test. The volcanic soil used in this study is classified as pumiceous tuff, which is derived from older volcanic rocks. The highest value of the oedometer modulus of compacted volcanic soils is 10.38 MPa which comes from eight (8) times passes of smooth drum roller conducted on field compaction trial test.
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Kai, Yutaka, Jun-ichiro Hamada, Motohiro Morioka, Shigetoshi Yano, and Jun-ichi Kuratsu. "Evaluation of the Stability of Small Ruptured Aneurysms with a Small Neck after Embolization with Guglielmi Detachable Coils: Correlation between Coil Packing Ratio and Coil Compaction." Neurosurgery 56, no. 4 (April 1, 2005): 785–92. http://dx.doi.org/10.1227/01.neu.0000156790.28794.ea.
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Abstract OBJECTIVE: Because it is difficult to predict the compaction of Guglielmi detachable coils (GDCs) after endovascular surgery for aneurysms, we studied the relationship between the coil packing ratio and compaction. Here, we propose a simple method for the preoperative estimation of coil compaction. Using follow-up angiograms, we studied the timing and degree of coil compaction in small terminal and side-wall aneurysms with narrow necks. METHODS: We studied 62 patients with acute ruptured intracranial aneurysms that were small (<10 mm), had a small neck (<4 mm), and were coil embolized with GDC-10s. The aneurysmal volume was calculated using the equation V = 4/3π(a/2) × (b/2) × (c/2), where a, b, and c are the aneurysmal height, length, and width in millimeters, respectively. The coil volume was calculated using the equation V = π(p/2)2 × l × 10, where p represents the GDC-10 coil diameter (0.25 mm) and l is the coil length. We recorded the maximum prospective coil length, L, as that corresponding with the volume of packed coils occupying 30% of the aneurysmal volume. Therefore, L was calculated as L (cm) = 0.3 × a × b × c, and the coil packing ratio was expressed as packed coil length/L × 100. Angiographic follow-up studies were generally performed at 3 months and 1 and 2 years after endovascular surgery. We considered coil compaction exceeding 2 mm as major compaction and recorded minor compaction when it was less than 2 mm of the empty reappeared space in the embolized aneurysm. Aneurysmal location was recorded as terminal or side wall. RESULTS: Of the 62 patients, 16 (25.8%) manifested angiographic coil compaction (10 minor and 6 major compactions); the mean coil packing ratio was 51.9 ± 13.4%. The mean coil packing ratio in the other 46 patients was 80.5 ± 20.2%, and the difference was statistically significant (P < 0.01). In all 6 patients with major compaction, the mean packing ratio was less than 50% and all underwent re-embolization after a mean of 24.9 ± 1.1 months. The 10 patients with minor compaction were conservatively treated, and the degree of compaction did not change during a mean period of 24 months. We detected 93.8% of the compactions within 12 months of coil placement. The aneurysm was of the terminal type in 5 of the 6 patients with major coil compaction. CONCLUSION: In patients who underwent embolization with GDC-10s of aneurysms that were small and had a small neck, the optimal coil packing ratio could be identified with the formula 0.3 × a × b × c. The probability of coil compaction was significantly higher when the coil packing ratio was less than 50%. To detect coil compaction after embolization, follow-up angiograms must be examined regularly for at least 12 months. To detect major coil compaction in patients with terminal type aneurysms, angiographic follow-up should not be shorter than 24 months.
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Toste, Alexandra, and Nuno Cardim. "Compacting knowledge in left ventricular non-compaction." Revista Portuguesa de Cardiologia (English Edition) 35, no. 10 (October 2016): 523–24. http://dx.doi.org/10.1016/j.repce.2016.09.002.
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Toste, Alexandra, and Nuno Cardim. "Compacting knowledge in left ventricular non-compaction." Revista Portuguesa de Cardiologia 35, no. 10 (October 2016): 523–24. http://dx.doi.org/10.1016/j.repc.2016.08.003.
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Zhou, Changhong, Xueyan Liu, Panos Apostolidis, A. Scarpas, and Liang He. "Induction Heating-Assisted Compaction in Porous Asphalt Pavements: A Computational Study." Applied Sciences 8, no. 11 (November 20, 2018): 2308. http://dx.doi.org/10.3390/app8112308.
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Low temperature asphalt (LTA) technologies, such as warm-mixed asphalt mixes, are utilized in the paving industry to lower energy demands and greenhouse gas emissions during asphalt mixing and pavement construction. However, the asphalt mixes developed that incorporate LTA additives are more sensitive than hot-mixed asphalts to temperature reduction during compaction, which leads to inadequate compaction and subsequent poor pavement performance. The induction heating-assisted compaction of pavement structures appears to be an effective way to ameliorate such issues and to improve mix compactability at lower temperatures. Considering that induction-assisted compaction is a complex process, a computational methodology is proposed in this paper. A porous asphalt concrete mix was considered as case material. For the pavement compaction analyses after induction, the temperature field generated by electromagnetic induction was predicted and the material parameters of asphalt mortar were adjusted. The effect of induction heating on asphalt compaction effectiveness, the tendency of mix density changing, the increase in compactor passes, and the influence of temperature on compaction at different locations in the pavement were studied as well.
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Sano, Yukio, Kiyohiro Miyagi, and Peter Arathoon. "Nonunique Dynamic Equilibrium Constitutive Relation of Metal Powder Depending on its Microstructure." Journal of Engineering Materials and Technology 118, no. 1 (January 1, 1996): 12–18. http://dx.doi.org/10.1115/1.2805926.
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It was observed in an earlier work by Morimoto et al. [Inst. Phys. Conf. Ser. No. 70, Oxford 1984, p. 427] that the dynamic compact of an aluminium powder medium had greater flakiness and contiguity ratio than the static compact of the same density. This observed difference in micro structure is used to explain their result that the dynamic pressure of the medium is higher than the static pressure for a given density: the degree of rotation of particles during compaction is assumed to decrease for higher strain rates, because of the shorter time available, causing an increase in plastic particle deformation in the compaction direction, and increased resistance to the compaction. The normal Hugoniot equation derived, in which the mean strain rate averaged over a single steady wavefront is introduced, indicates that a rise of the normal Hugoniot with an increase in the strain rate results macroscopically from the increase in the propagation velocity of the wavefront. The multiwave Hugoniot equation is found to depend on the strain rate history of a given material. In compactions of a metal powder medium by punch impact, the wavefronts passing through the medium are approximately steady if the punch mass is sufficiently larger than the medium mass. But both the number of wavefronts arising during the compaction and the amplitudes of the strain waves, and hence the strain rate histories, vary with compaction conditions such as punch mass and initial punch velocity. This implies that a dynamic equilibrium constitutive relation for the medium will depend on the compaction conditions, and therefore cannot be determined uniquely for any two compactions.
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Widyastuti, Rindang Fajarin, Faizah Ali, Sugiarto Putra Wijaya, Eka Nurul Falah, and Iyando Aditiyawan. "Investigation of the Dwelling Time and Compaction Pressure Effect on Mechanical Properties and Microstructure of the Cu-Sn Composite." Key Engineering Materials 939 (January 25, 2023): 57–62. http://dx.doi.org/10.4028/p-y6pg8i.
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Powder metallurgy has become a compatible alternative method in term of manufacturing complex component, such as frangible bullet. A bullet with frangible properties can be manufactured by using copper-based metal matrix composite with tin as the reinforce. During compaction process, the applied load and dwelling time are considered as substantial factor which affect the final product. Therefore, the aim of the present work study is to observe the pressure and the holding time during the compacting process (dwelling time) which has an impact on the mechanical properties of the Cu-Sn composite product. The green component or pressed product is tested with various compaction pressure variables, namely 500, 600, and 700 MPa with 0, 5, 15, 30, 45 minutes dwelling time, respectively. The sintering process is performed at 260°C for 30 minutes in the horizontal furnace. The result shows that the surface contact area was increased along with the compaction load upsurge which led to low porosity green compact. The 700 MPa compaction pressure with 15 minutes dwelling time has the optimum density, hardness, and compressive strength, which had 8,454 gr/cm3, 87 HRF and 349.74 MPa in value. The compacting product has been tested on Scanning Electron Microscope (SEM) and showed that 700 MPa compaction pressure had the best powder densification process.