Journal articles: 'Compression test'

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Anggraini, Nurti Kusuma, Seno Suharyo, and Desy Ratna Arthaningtyas. "ANALISIS UJI KUAT TEKAN PAVING BLOCK DENGAN COMPRESSION TEST DAN HAMMER TEST." Menara: Jurnal Teknik Sipil 18, no. 2 (July 8, 2023): 159–65. http://dx.doi.org/10.21009/jmenara.v18i2.36679.

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Based on its quality, paving blocks are used in the construction sector and an alternative choice for surface pavement layers. Several other advantages are concrete bricks (paving blocks) better than other pavements and are economical in maintenance, artistic in terms of the exterior of a building, do not require heavy equipment to work/install, and can be mass-produced. This study aims to compare the compressive strength of paving blocks using a compression test and hammer test and to determine the quality of paving blocks. In this study there are 9 objects, 3 different shapes of paving blocks consist of 3 pieces of each form. The form of paving blocks used are brick paving blocks, hexagons and worms (univape). Based on the test results, there is a difference in the compressive strength value of the compression test and the hammer test, where the compression test compressive strength value is greater than the hammer test compressive strength value. The results of the compressive strength test showed that the paving blocks were in the category of quality B paving blocks.

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Huang, Zhong Hua, Shao Jun Liu, Ying Guang Xu, and Wang Hu. "Seafloor Polymetallic Sulfides Mechanical Property Test." Advanced Materials Research 1015 (August 2014): 316–19. http://dx.doi.org/10.4028/www.scientific.net/amr.1015.316.

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Seafloor polymetallic sulfide specimens were developed according to engineering rock test method standard (GB/T 50266-2013). Seafloor polymetallic sulfide wet density and dry density were tested. Uniaxial compressive strength and triaxial compression strength of seafloor polymetallic sulfide were tested using rock mechanics test system MTS 815. Elasticity modulus and Poisson's ratio of seafloor polymetallic sulfide were calculated based on specimens stress-strain curves. Cohesion and internal friction angle were calculated based on specimens triaxial test Mohr stress circle. Test results show that seafloor polymetallic sulfide dry density average value is 2.6 g/cm3, wet density average value is 2.94 g/cm3. Uniaxial compressive strength and triaxial compression strength of seafloor polymetallic sulfide are unstable. Average value of the uniaxial compressive strength is 10.243MPa. Average value of triaxial compression strength test peak load is 47.166KN. Cohesion is 2.447MPa and internal friction angle is 38.04o.

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McCluskey, E. J., D. Burek, B. Koenemann, S. Mitra, J. Patel, J. Rajski, and J. Waicukauski. "Test data compression." IEEE Design & Test of Computers 20, no. 2 (March 2003): 76–87. http://dx.doi.org/10.1109/mdt.2003.1188267.

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CHEN, S. C. "The Scaphoid Compression Test." Journal of Hand Surgery 14, no. 3 (June 1989): 323–25. http://dx.doi.org/10.1016/0266-7681_89_90094-6.

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A clinical test for scaphoid waist fractures is described in which the first ray is compressed longitudinally. This has the advantage that it can be done when the patient is in a plaster cast. Of 52 patients with suspected scaphoid fractures, 37 had negative tests and proved by X-rays then and later to have no fracture. 12 had positive tests and X-rays. Two patients with positive tests had fractures nearby: one of the scaphoid tuberosity and one of the radial styloid. One patient with a negative test had de Quervain’s disease. Once union has occurred, the test becomes negative.

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CHEN, S. "The scaphoid compression test." Journal of Hand Surgery: Journal of the British Society for Surgery of the Hand 14, no. 3 (August 1989): 323–25. http://dx.doi.org/10.1016/0266-7681(89)90094-6.

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Kim, Yang-Soo, Jung-Man Kim, Kee-Yong Ha, Soon Choy, Min-Wook Joo, and Yang-Guk Chung. "The Passive Compression Test." American Journal of Sports Medicine 35, no. 9 (September 2007): 1489–94. http://dx.doi.org/10.1177/0363546507301884.

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Background Even though there are several physical tests available for superior labrum anterior posterior lesions, there have been very few reports on their accuracy, and none can be regarded as completely predictive for the presence of a superior labrum anterior posterior lesion in the shoulder joint. Hypothesis This new clinical test is a useful and accurate technique for detecting superior labral tears in the shoulder joint. Study Design Cohort study (diagnosis); Level of evidence, 2. Methods This test was conducted independently by 2 physicians before any other diagnostic evaluation. In all cases, the glenohumeral joint was investigated first, and the appropriate treatments were performed on the lesion. A protocol was established to evaluate the sensitivity, specificity, and positive and negative predictive values of this new clinical test. The reproducibility of this test was evaluated with a κ coefficient. Results Sixty-one patients (61 shoulders) were examined with the passive compression test, and all underwent arthroscopic surgery. In 31 patients with a positive passive compression test result, 27 had a superior labrum anterior posterior lesion, and in 30 patients with a negative passive compression test result, 6 had a superior labrum anterior posterior lesion. The sensitivity of the test was 81.8%, and the specificity was 85.7%. The positive predictive value was 87.1%, and the negative predictive value was 80.0%. The κ coefficient was 0.771 between the 2 independent examiners (P < .01). Conclusion The passive compression test is a useful and accurate technique for predicting superior labral tears of the shoulder joint.

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TIERI, O., A. POLZELLA, and V. IURA. "THE ISOTONOMETRIC COMPRESSION TEST." Acta Ophthalmologica 51, no. 2 (May 27, 2009): 129–41. http://dx.doi.org/10.1111/j.1755-3768.1973.tb03789.x.

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Kumar, Amit, Mark Kassab, Elham Moghaddam, Nilanjan Mukherjee, Janusz Rajski, Sudhakar M. Reddy, Jerzy Tyszer, and Chen Wang. "Isometric Test Data Compression." IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems 34, no. 11 (November 2015): 1847–59. http://dx.doi.org/10.1109/tcad.2015.2432133.

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Tanuja*, P. S. L., and Mrs K. Prasanthi. "Reduction of Test Data with Hybrid Test Points." International Journal of Innovative Technology and Exploring Engineering 9, no. 3 (January 30, 2020): 2535–38. http://dx.doi.org/10.35940/ijitee.c7969.019320.

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ATPG vectors for a combinational circuit exhibit correlations among the bits of a test vector. We propose a BIST circuit design methodology using spectral methods which utilizes the correlation information. This circuit serves dual purposes. It generates BIST vectors that are similar to the ATPG vectors with higher test coverage as compared to random and weighted random vectors. The same circuit can also function as a test data de-compressor for compressed ATPG vectors applied from an external tester. Logic built-in self-test (LBIST) is now increasingly used with on-chip test compression as a complementary solution for in-system test, where high quality, low power, low silicon area, and most importantly short test application time are key factors affecting ICs targeted for safety-critical systems. Test points, common in LBIST-ready designs, can help to reduce test time and the overall silicon overhead so that one can get desired test coverage with the minimal number of patterns. Typically, LBIST test points are dysfunctional when enabled in an ATPG-based test compression mode. Similarly, test points used to reduce ATPG pattern counts cannot guarantee desired random testability. We present a hybrid test point technology designed to reduce deterministic pattern counts and to improve fault detection likelihood by means of the same minimal set of test points. The hybrid test points are subsequently deployed in a scan-based LBIST scheme addressing stringent test requirements of certain application domains such as the automotive electronics market. These requirements, largely driven by safety standards, are met by significantly reducing test application time while preserving the high fault coverage. The new scheme is a combination of pseudorandom test patterns delivered in a test-per-clock fashion through conventional scan chains and per cycle-driven hybrid observation test points that capture faulty effects every shift cycle into dedicated scan chains. We also exhibit test data compression capabilities of the proposed BIST architecture. This architecture provides a maximum test data compression exceeding and a proportional test time reduction for serial interface reseeding.

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Wang, Hong Yun, and Hui Qiang Zheng. "Shear and Squeeze Rheometry of Magnetorheological Fluids." Advanced Materials Research 305 (July 2011): 344–47. http://dx.doi.org/10.4028/www.scientific.net/amr.305.344.

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The mechanical properties of a magnetorheological (MR) fluid in shearing, compression and shearing after compression have been studied in the magnetic field which is generated by a coil carrying different magnitudes of DC electrical current on a self-constructed test system. The relations of compression stress versus compression strain, yield stress versus compression stress were studied under different magnetic fields. The compressing tests showed that the MR fluid is very stiff at small compressive strains lower than 0.13. The shear yield stress of MR fluids after compression was much stronger than that of uncompressed MR fluids under the same magnetic field. The enhanced shear yield stress of MR fluids can be utilized to design the MR clutch and brake for new structure and will make MR fluids technology attractive for many applications.

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Kong, De Quan, and Rong Wan. "Study on Confined Consolidation Test of Natural Loess." Advanced Materials Research 250-253 (May 2011): 1543–46. http://dx.doi.org/10.4028/www.scientific.net/amr.250-253.1543.

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The main object of study is the natural loess. The confined compression test and confined compression resilience test of nature loess and remolded loess under nature water content condition was done separately by using unsaturated high pressure consolidation apparatus. Through comparisons of test data, we investigated the effects of overconsolidated and structural factors on the loess compressibility under specific moisture conditions and analyzed the natural laws of compressive deformation properties of loess.

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Yamashita, Minoru, and Yasuhisa Sato. "Improvement of Drop-Hammer Compression Test for Rubber Material." Materials Science Forum 673 (January 2011): 259–64. http://dx.doi.org/10.4028/www.scientific.net/msf.673.259.

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The drop-hammer compression testing method where the stroke is calculated by solving the equation of motions of the drop-hammer and anvil was improved in order to determine the strain-rate dependence of the elastic modulus of rubber material. An additional tool for interrupting the compression was embedded in the apparatus. The tool was a thick washer which informed the time when the prescribed compressive strain was achieved by the sharp increase of compression force. The oscillatory stress-time curve obtained by the load cell was appropriately smoothed employing the method of moving average. The effect of the friction at the interface between the rubber specimen and the tools was properly eliminated by the extrapolating method using the specimens with several variations in heights. The stress-strain relationship was obtained under the dynamic condition. The numerical simulation of impact compression disclosed that the effect of inertia on the deformation pattern was practically small under the experimental condition adopted. Conducting the low-speed compression tests, the dependence in elastic modulus of rubber material on the strain-rate was appropriately determined.

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Xiao, Jian, Zhiming Tan, and Jingliang Chen. "Mechanical Analysis of Unconfined Compression Test of Cylinder." Transportation Research Record: Journal of the Transportation Research Board 2672, no. 27 (August 22, 2018): 37–44. http://dx.doi.org/10.1177/0361198118791912.

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The unconfined compression test is widely used because of convenient specimen formation, simple experimental process, and low requirement for equipment. In view of the experimental characteristics, the axisymmetric mechanical model of a cylinder with horizontal friction was constructed and its elastic analytic solution was also deduced. The stress and the strain of the cylinder under unconfined compression with different boundary conditions were analyzed by using the analytical solution, and the failure characteristics of the cylinder under unconfined compression were studied and verified by laboratory testing. The results showed that the end restraint effect of the cylinder increased with the decrease of the height-to-diameter ratio and the increase of the Poisson ratio. When the end surface of the cylinder was constrained, the maximum tensile strain appeared in the middle of the cylindrical side; its value increased with the constraint effect, and greater loads were needed to make the same vertical displacement. The compressive strength derived from the current method would be too weak, and the compressive modulus of elasticity would be too great. If the end constraint was large, a small network crack first formed in the middle of the outer side of the cylinder, forming the double-tapered destruction. If the end face was weakly restrained, the cracks descended from the top to the bottom, and the specimens split.

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Yan, Feng, and Nan Pang. "Low Strength Self Compacting Concrete Compressive Strength Test." Applied Mechanics and Materials 275-277 (January 2013): 2041–44. http://dx.doi.org/10.4028/www.scientific.net/amm.275-277.2041.

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In this paper,the mechanical properties were studied,the self compacting concrete cubic compression strength,prismatic compressive strength test,discussed two kinds of relationship between intensity index.

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Meinich-Bache, Øyvind, Kjersti Engan, Tonje Søraas Birkenes, and Helge Myklebust. "Real-Time Chest Compression Quality Measurements by Smartphone Camera." Journal of Healthcare Engineering 2018 (October 28, 2018): 1–12. http://dx.doi.org/10.1155/2018/6241856.

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Out-of-hospital cardiac arrest (OHCA) is recognized as a global mortality challenge, and digital strategies could contribute to increase the chance of survival. In this paper, we investigate if cardiopulmonary resuscitation (CPR) quality measurement using smartphone video analysis in real-time is feasible for a range of conditions. With the use of a web-connected smartphone application which utilizes the smartphone camera, we detect inactivity and chest compressions and measure chest compression rate with real-time feedback to both the caller who performs chest compressions and over the web to the dispatcher who coaches the caller on chest compressions. The application estimates compression rate with 0.5 s update interval, time to first stable compression rate (TFSCR), active compression time (TC), hands-off time (TWC), average compression rate (ACR), and total number of compressions (NC). Four experiments were performed to test the accuracy of the calculated chest compression rate under different conditions, and a fifth experiment was done to test the accuracy of the CPR summary parameters TFSCR, TC, TWC, ACR, and NC. Average compression rate detection error was 2.7 compressions per minute (±5.0 cpm), the calculated chest compression rate was within ±10 cpm in 98% (±5.5) of the time, and the average error of the summary CPR parameters was 4.5% (±3.6). The results show that real-time chest compression quality measurement by smartphone camera in simulated cardiac arrest is feasible under the conditions tested.

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Shimizu, Ichiro. "New Biaxial Compression Test Device for Metallic Materials with Reverse-Type Differential Rotary to Linear Conversion Mechanism." Applied Mechanics and Materials 83 (July 2011): 141–46. http://dx.doi.org/10.4028/www.scientific.net/amm.83.141.

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New rotary to linear conversion mechanism named "reverse-type differential rotary to linear conversion mechanism (RDRLCM)" was invented for simultaneous achievement of large load capacity and precise displacement control, for compression test devices and press forming machines. The new mechanism was developed and incorporated as loading systems into an original biaxial compression test device, and thus, its fundamental performance was investigated. The results revealed that the loading system by the new rotary to linear conversion mechanism were able to generate compression force of about three times larger than that by a conventional feed-screw mechanism for the same input torque. In addition, the generated compressive force was maintained while the compressive motion was interrupted. These facts confirm the advantage to use RDRLCM for compression test devices as well as for press forming machines.

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Yao, Jia Wei, Yu Pu Song, Li Kun Qin, and Ling Xia Gao. "Mechanical Properties and Failure Criteria of Concrete under Biaxial Tension and Compression." Advanced Materials Research 261-263 (May 2011): 252–55. http://dx.doi.org/10.4028/www.scientific.net/amr.261-263.252.

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Utilizing the large static-dynamic triaxial test system, 7 proportional loading biaxial tensile and compressive tests of concrete were conducted. The proportional loading paths are 0 (uniaxial compression), -0.05, -0.1, -0.15, -0.2, -0.25 and ∞ (uniaxial tension). Compressive and tensile strength were measured as well as the strains at two loading directions. Considering the ratio to tension and compression, failure criteria of ordinary concrete under biaxial tension and compression was established, which has a good agreement with test value.

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KANETAKE, Naoyuki. "Compression Test of Porous Metals." Journal of the Japan Society for Technology of Plasticity 50, no. 586 (2015): 1004–8. http://dx.doi.org/10.9773/sosei.50.1004.

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Gonciari, P., N. Nicolici, and B. Al-Hashimi. "Test cost reduction through compression." Electronics Systems and Software 1, no. 3 (June 1, 2003): 37–41. http://dx.doi.org/10.1049/ess:20030307.

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Balakrishnan, Kedarnath J., and Nur A. Touba. "Improving Linear Test Data Compression." IEEE Transactions on Very Large Scale Integration (VLSI) Systems 14, no. 11 (November 2006): 1227–37. http://dx.doi.org/10.1109/tvlsi.2006.886417.

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Verma, Nikhil N., Mark Drakos, and Stephen J. O’Brien. "The Arthroscopic Active Compression Test." Arthroscopy: The Journal of Arthroscopic & Related Surgery 21, no. 5 (May 2005): 634.e1–634.e4. http://dx.doi.org/10.1016/j.arthro.2005.02.008.

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Banks, Nigel H., Colin A. Borton, and Marilyn Joseph. "Compression bruising test for bananas." Journal of the Science of Food and Agriculture 56, no. 2 (1991): 223–26. http://dx.doi.org/10.1002/jsfa.2740560212.

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Gyurkó, Zoltán, Katalin Bagi, and Adorján Borosnyói. "Discrete Element Modelling of uniaxial compression test of hardened concrete." Epitoanyag - Journal of Silicate Based and Composite Materials 66, no. 4 (2014): 113–19. http://dx.doi.org/10.14382/epitoanyag-jsbcm.2014.21.

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Chandra, Anshuman, and Krishnendu Chakrabarty. "Analysis of Test Application Time for Test Data Compression Methods Based on Compression Codes." Journal of Electronic Testing 20, no. 2 (April 2004): 199–212. http://dx.doi.org/10.1023/b:jett.0000023682.41142.44.

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Zubaidah, Isa, Abdullah Norfatriah, Serbini Zatul Amali, and Abu Zuruzi. "Preparation and Behavior of Bamboo Fiber-Reinforced Polydimethylsiloxane Composite Foams during Compression." Fibers 6, no. 4 (November 29, 2018): 91. http://dx.doi.org/10.3390/fib6040091.

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This study investigates the mechanical properties of bamboo fiber-reinforced polydimethylsiloxane (BF-PDMS) foams with up to 3.4% (by mass) fiber during compression. Pristine PDMS foams and BF-PDMS composite foams were fabricated using a sugar leaching method. Compression test results of pristine PDMS and BF-PDMS composite foams display plateau and densification regions. Predictions of a modified phenomenological foam (PF) model based on Maxwell and Kelvin–Voight models are in good agreement with compression test results. Stiffness coefficients were extracted by fitting results of compression tests to the modified PF model. Spring and densification coefficients of BF-PDMS composite foams are 2.5- and 15-fold greater than those of pristine PDMS foams, respectively. Strains corresponding to onset of densification computed using extracted coefficients were 35% and 25% for pristine PDMS foams and BF-PDMS composite foams, respectively. Compressing foams at 6.0 and 0.5 mm/min results in highest and lowest compressive stress, respectively. Insights from this study are useful in many areas such as environmental protection, pressure sensing, and energy where PDMS composite foams will find applications.

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Sujarwo, Surya. "Percepatan Perhitungan Hasil Tes Sistem Online menggunakan Kompresi Database." ComTech: Computer, Mathematics and Engineering Applications 4, no. 2 (December 31, 2013): 1289. http://dx.doi.org/10.21512/comtech.v4i2.2658.

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The article explores the influence of database compression on processing time in generating online test results through experimental study. The study uses three level compressions consists of none, row and page in table used by online test system. The experiment shows that using page compression results in faster processing time and less space compared to none and row compression, and the optimal row for compression is between 1001 and 2000 rows. In summary, to reduce space usage and processing time, it is better to use page compression in user answer table of online test system and to group the participant in schedule so that users’ answer will be between 1001 and 2000 rows.

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Das, B. M., S. C. Yen, and R. N. Dass. "Brazilian tensile strength test of lightly cemented sand." Canadian Geotechnical Journal 32, no. 1 (February 1, 1995): 166–71. http://dx.doi.org/10.1139/t95-013.

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Tensile stress – tensile strain relationships for lightly cemented sand specimens obtained by conducting Brazilian tensile strength tests have been presented. The tensile strain measurement was done by using an optical image analysis technique. In addition to the tensile strength tests, some unconfined compression tests on sand specimens with varying cement contents were also performed. Based on the results of the above tests, a nondimensional tensile stress – tensile strain relationship has been presented. Also the variation of the tensile and compressive strength and strain ratios with varying cement contents have been discussed. Key words : lightly cemented sand, optical image analysis, tensile strain, tensile strength, unconfined compression strength.

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Yao, Wang, Xi’an Li, Youjun Wu, Quan Xue, Zhitao Hao, Jianfeng Shi, Chen Zhang, and Yongbiao Ren. "Effect of Height-to-Diameter Ratio on the Compression Test Results of Remodeled Loess and Its Mechanism." Buildings 13, no. 1 (January 9, 2023): 176. http://dx.doi.org/10.3390/buildings13010176.

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The confined compression test is the most widely used test to study the compressive deformation of soil in a laboratory, and the height–diameter (H/D) ratio has a significant effect on the confined compression test results. However, there has been limited research on the effect of the H/D ratio on loess compression deformation. In this work, a series of confined compression tests were carried out on the remolded loess samples using a modified oedometer to explore the effect of the H/D ratio on the compression deformation. Scanning electron microscopy (SEM) tests were used to investigate the variation of the microstructure in soils with different H/D ratios along the sample height. The results showed that the axial strain of the remolded loess decreases with the increase in the H/D ratio. The influence of the H/D ratio on the compression deformation is not obvious at lower pressures and compaction degrees, but it is significantly enhanced when the H/D ratio is beyond 0.65. The compression curves of the remolded loess samples with different H/D ratios fit the Gompertz equation well, and the transition point of the compression curves becomes difficult to identify with the increase in the H/D ratio. The compression index (Cc) decreases exponentially as a function of the H/D ratio, while the compressive yield stress (Pc) increases linearly with the increase in the H/D ratio. SEM analysis showed that, with the increase in the H/D ratio, the compression deformation of the sample changed from the whole sample involved in compression to the part of the soil in contact with the pressure. The compression of loess is mainly dominated by the compression of macropores and mesopores. The development of the soil–ring wall friction on the compression deformation induced by the H/D ratio was analyzed based on the change in microstructure, and a three-stage development of the soil–ring wall friction was established. These results and analysis established the connection between the specification and the literature, providing strong support for the rationality of the confined compression test results.

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Kusaka, Takayuki, Takanori Kono, Yasutoshi Nomura, and Hiroki Wakabayashi. "Dynamic Compression Test of CFRP Laminates Using SHPB Technique." Applied Mechanics and Materials 566 (June 2014): 122–27. http://dx.doi.org/10.4028/www.scientific.net/amm.566.122.

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A novel experimental method was proposed for characterizing the compressive properties of composite materials under impact loading. Split Hopkinson pressure bar system was employed to carry out the dynamic compression tests. The dynamic stress-strain relations could be precisely estimated by the proposed method, where the ramped input, generated by the plastic deformation of a zinc buffer, was effective to reduce the oscillation of the stress field in the specimen. The longitudinal strain of gage area could be estimated from the nominal deformation of gage area, and consequently the failure process could be grasped in detail from the stress-strain relation. The dynamic compressive strength of the material was slightly higher than the static compressive strength. In addition, the validity of the proposed method was confirmed by the computational and experimental results.

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Liu, Shi, and Jinyu Xu. "Experimental and Numerical Analysis of Qinling Mountain Engineered Rocks during Pulse-Shaped SHPB Test." International Journal of Nonlinear Sciences and Numerical Simulation 16, no. 3-4 (June 1, 2015): 165–71. http://dx.doi.org/10.1515/ijnsns-2014-0039.

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AbstractIn order to study the dynamic compression mechanical properties of engineering rock under high strain rate （100~102 S−1）loads, dynamic compression tests of three common engineering rocks (marble, sandstone and granite) taken from the Qinling Mountain are studied subjected to five different kinds of shock air pressure using Φ 100 mm split Hopkinson pressure bar test system improved with purple copper waveform shaper. The dynamic compression stress-strain curves, dynamic compressive strength, peak strain, energy absorption rate and elastic modulus of three rocks variation with strain rate are researched. The dynamic compression failure modes under different strain rates are analyzed. Then the three-dimensional numerical simulations of waveform shaper shaping effects and stress wave propagation in the SHPB tests are carried out to reproduce the test results. The research results show that the dynamic compression stress-strain curves show certain discreteness, and there is an obvious rebound phenomenon after the peak. With the increase in strain rate, the dynamic compressive strength, peak strain and energy absorption rate are all in a certain degree of increase, but the elastic modulus have no obvious change trend. Under the same strain rate, the dynamic compressive strength of granite is greatest while of sandstone is least. With the increase in strain rate, the margin of increase in peak strain and energy absorption rate of granite is greatest while of sandstone is least. The failure modes of the sample experience a developing process from outside to inside with the increase of strain rate.

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Mašek, Bohuslav, David Aišman, Hana Jirková, and Stefan Wurster. "Micro-Compression Test of Thixoformed Austenite." Solid State Phenomena 192-193 (October 2012): 215–18. http://dx.doi.org/10.4028/www.scientific.net/ssp.192-193.215.

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Thixoforming is an alternative forming method, by which intricate and complex-shaped products can be manufactured using a single production step. This technology allows a material’s microstructure to be altered profoundly. Typical microstructure of steels processed in this manner consists of quasi-polyhedral austenite grains embedded in a ledeburite-carbide network. This type of microstructure was produced by processing the experimental material in this study: the X210Cr12 steel. Since austenite is a metastable component depending on oversaturation with a number of elements, its thermal and mechanical stability needs to be known. This information is required for further modification and enhancment efforts. In previous experiments, the thermal stability was tested by thermal exposure. In the present work, the behaviour of austenite was explored under mechanical load at room temperature in a micro-compression test. A single block of austenitic material was used for making a test specimen with the dimensions of 2.4×2.2×4.9 µm. Its mechanical properties were measured and deformation stability was investigated using compressive deformation.

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Zhi, Chao, and Hai Ru Long. "Investigation on Compression Properties of Syntactic Foam Reinforced by Warp Knitted Spacer Fabric." Advanced Materials Research 1095 (March 2015): 531–34. http://dx.doi.org/10.4028/www.scientific.net/amr.1095.531.

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The study aimed to investigate the compression behaviors of syntactic foam reinforced by warp knitted spacer fabric (SF-WKSF). Two kinds of SF-WKSF samples were prepared with warp knitted spacer fabric (WKSF) of different surface layer structures. The compression tests were carried out by MTS 810 material test system and the compression properties of SF-WKSF were analyzed based on its compressive stress–strain curves and modulus values obtained from test results. It is indicated that the surface layer structure of WKSF has significant effects on the compression performance of SF-WKSF, the SF-WKSF made with denser surface layer structure shows higher compressive modulus and yield strength compared to neat syntactic foam (NSF).

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Qi, Zhaogang, Jun Yang, Jiangping Chen, Haifeng Zhang, and Li Zhang. "Experimental investigation on a two-stage CO2 compressor with high back pressure." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 226, no. 7 (November 10, 2011): 1811–20. http://dx.doi.org/10.1177/0954406211428245.

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In this article, two samples of two-stage rolling piston CO2 compressors with and without intercooler are developed and experimentally studied. These CO2 compressors are high back-pressure compressors, which mean the pressure inside compressor shell is the discharge pressure of the second stage. A test rig was designed to measure the performance and efficiency of this compressor. The test results show that the suction vapor temperature at the second stage inlet pipe has few influences on the performance and efficiency of the first compressor sample with intercooler. The volumetric efficiency linearly decreases with the increase of compression ratio of the suction and discharge pressure, and the volumetric efficiency can maintain in a relative constant range during a wide compression ratio changes in this high back-pressure design. There exists an optimum compression ratio for each suction pressure at the first stage, where the compressor isentropic efficiency is maximum. A generalized volumetric efficiency correlation for two-stage CO2 rolling piston compressor as a function of compression ratio is proposed and it can describe 100% of the test data within ±5.0% with a mean deviation of 1.7%. This would be helpful as a guide for designing such type compressor.

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Mohd Ghazali, Farah Amira, and Ardiyansyah Syahrom. "Mechanical Behaviour of Cancellous bone: Compression and Three-Point Bending Test." Malaysian Journal of Fundamental and Applied Sciences 18, no. 3 (August 4, 2022): 295–303. http://dx.doi.org/10.11113/mjfas.v18n3.2274.

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The mechanical properties of cancellous bone are fundamental in providing structural support and flexibility during physical activities. Characterization of cancellous bone properties and its mechanical behaviour were found crucial as information of the elastic and failure properties of the tissue may potentially be used to study the effects of drug treatments, aging and disease at the tissue level. This study aims to present the difference of mechanical properties of cancellous bone between compressive and three-point bending loads. Cancellous bone specimens from the femoral and tibial condyles of bovines were mechanically tested using three-point bending test and compression test and correlated with morphological parameters such as bone volume fraction and porosity. From the results, significant difference of mechanical properties was found between cancellous bone specimens tested with compressive and three-point bending load. From compressive load, the maximum stress reached 4.2 MPa, whereas in three-point bending, maximum flexural stress reached 17.0 MPa. Cancellous bone strength was found to be much higher when tested with three-point bending load, although correlations with morphological parameters such as bone volume fraction (BV/TV) and porosity were found lower compared to that in compressive load. In conclusion, there are no correlation between compression and three-point bending with morphology indices (BV/TV and porosity).

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Li, Chunbao, Xiaosong Ma, Shifeng Xue, Haiyang Chen, Pengju Qin, and Gaojie Li. "Compressive Capacity of Vortex-Compression Nodular Piles." Advances in Civil Engineering 2021 (January 12, 2021): 1–18. http://dx.doi.org/10.1155/2021/6674239.

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Compared with traditional equal-section pile, the nodular parts of nodular pile expand the contact area between the pile and foundation soil, which can greatly improve the bearing capacity of pile foundation and increase the stability of pile body structure. In this paper, the mechanism of pile-soil interaction in the construction of vortex-compression nodular pile is studied with the purpose of evaluating the compressive capacity of nodular piles. Through the indoor model test and ABAQUS numerical simulation analysis, the compressive characteristics of 12 types of vortex-compression nodular pile are obtained, and the variation rules of the parameters of the compressive characteristics of vortex-compression nodular piles are quantitatively analyzed, including the failure pattern of foundation soil, load-settlement relationship, and load transfer law of vortex-compression nodular piles. The results showed that the compressive capacity of vortex-compression nodular piles has significant advantages over that of traditional equal-section piles. Based on the results of the indoor model test and numerical simulation, the calculation method and formula of the compressive capacity of vortex-compression nodular piles are given by modifying the corresponding calculation formula of traditional nodular piles. The new method and formula are more in line with the actual working conditions and provide theoretical and data support for the further engineering application of vortex-compression nodular piles.

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Xie, Bing, Jin Jun Guo, and Xiang Xia. "Influence of Loading Rate on Uniaxial Compression Test of Rock Specimen with Random Joints." Advanced Materials Research 396-398 (November 2011): 217–20. http://dx.doi.org/10.4028/www.scientific.net/amr.396-398.217.

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Numerical specimens with ramdom joints is established by particle flow code PFC2D and uniaxial compression tests are conducted under three different loading rate. Studies have shown that strength of uniaxial compression are all increased with the loading rate no matter what specimen is complete or with random joints. The sensitivity of changes of uniaxial compressive strength of specimen with random joints decreases with increasing of the loading rate.

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Yin, Yu Ting, Lian Yong Wang, and Jiu Ju Cai. "Study on Influence Factors to the Biomass Compression Process." Applied Mechanics and Materials 71-78 (July 2011): 2939–43. http://dx.doi.org/10.4028/www.scientific.net/amm.71-78.2939.

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The principle of biomass briquetting, the advantages and disadvantages of biomass briquette machine and the current research status were introduced in this paper. The influence of the four factors biomass particle size, moisture, pressure and compression speed to formation density and compressive strength was summarized, by orthogonal test method. The results show that, the influence of biomass size to the formation density is largest and to the compressive strength is least. The biomass size in the range of<40 mesh is best. The influence of compressing speed to compressive strength is largest and to formation density is least. The speed about 60mm/min is best. The influence of biomass moisture content and pressure cannot be neglected, 15% and 10MPa are best in this paper.

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Du, Haijun, Yanhua Ma, Ruoyan Li, Ting Lei, and Pei Wu. "Effect of vibrational frequency on alfalfa opening compression process." BioResources 17, no. 4 (October 14, 2022): 6706–17. http://dx.doi.org/10.15376/biores.17.4.6706-6717.

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To reveal the action mechanism of vibration frequency in alfalfa opening compression, a self-developed vibration compression test system was used to evaluate the variation of compression force during alfalfa open compression. A faster vibration frequency yielded a smaller compression force required for compressing alfalfa into blocks. Compared with free vibration compression, vibration compression was beneficial to release the internal stress of alfalfa block, reduce the forming pressure, and stabilize the high density. In the range of test vibration frequency, when the frequency was 15 Hz, the residual internal stress release ratio of alfalfa block was the highest, and the stable density of alfalfa block was the largest. Considering the pressure and alfalfa block density comprehensively, the optimized vibration frequency was approximately 15 Hz.

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Hsueh, Chun-Hway. "Slice Compression Tests Versus Fiber Push-In Tests." Journal of Composite Materials 28, no. 7 (May 1994): 638–55. http://dx.doi.org/10.1177/002199839402800704.

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Both the fiber push-in and the slice compression tests have been used to evaluate the interfacial properties of fiber-reinforced ceramic composites. Mechanics of sliding at the fiber-matrix interface obtained with these two tests are compared in the present study. While the interfacial radial stress induced by Poisson's effect is always compressive for the push-in test, it is tensile for the slice compression test when the fiber is stiffer than the matrix. This difference in Poisson's effect results in different interfacial frictional resistance between these two tests. Compared to the push-in test, the slice compression test produces a lower frictional resistance along the debonded interface. The interfacial frictional stress during unloading is lower than that during loading for the push-in test, but this trend is reversed for the slice compression test.

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Fortin, M., J. Soulhat, A. Shirazi-Adl, E. B. Hunziker, and M. D. Buschmann. "Unconfined Compression of Articular Cartilage: Nonlinear Behavior and Comparison With a Fibril-Reinforced Biphasic Model." Journal of Biomechanical Engineering 122, no. 2 (October 18, 1999): 189–95. http://dx.doi.org/10.1115/1.429641.

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Mechanical behavior of articular cartilage was characterized in unconfined compression to delineate regimes of linear and nonlinear behavior, to investigate the ability of a fibril-reinforced biphasic model to describe measurements, and to test the prediction of biphasic and poroelastic models that tissue dimensions alter tissue stiffness through a specific scaling law for time and frequency. Disks of full-thickness adult articular cartilage from bovine humeral heads were subjected to successive applications of small-amplitude ramp compressions cumulating to a 10 percent compression offset where a series of sinusoidal and ramp compression and ramp release displacements were superposed. We found all equilibrium behavior (up to 10 percent axial compression offset) to be linear, while most nonequilibrium behavior was nonlinear, with the exception of small-amplitude ramp compressions applied from the same compression offset. Observed nonlinear behavior included compression-offset-dependent stiffening of the transient response to ramp compression, nonlinear maintenance of compressive stress during release from a prescribed offset, and a nonlinear reduction in dynamic stiffness with increasing amplitudes of sinusoidal compression. The fibril-reinforced biphasic model was able to describe stress relaxation response to ramp compression, including the high ratio of peak to equilibrium load. However, compression offset-dependent stiffening appeared to suggest strain-dependent parameters involving strain-dependent fibril network stiffness and strain-dependent hydraulic permeability. Finally, testing of disks of different diameters and rescaling of the frequency according to the rule prescribed by current biphasic and poroelastic models (rescaling with respect to the sample’s radius squared) reasonably confirmed the validity of that scaling rule. The overall results of this study support several aspects of current theoretical models of articular cartilage mechanical behavior, motivate further experimental characterization, and suggest the inclusion of specific nonlinear behaviors to models. [S0148-0731(00)00702-0]

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Hidayat, B. A., and A. N. Ahyani. "An integrated approach for the strength evaluation on RC beams by the combination of hammer test and compression test." IOP Conference Series: Earth and Environmental Science 1195, no. 1 (June 1, 2023): 012011. http://dx.doi.org/10.1088/1755-1315/1195/1/012011.

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Abstract The structural performance of the old existing RC building needs to be evaluated, as it is susceptible to severe damage. There are two different types to examine the RC members’ capacity: the destructive and non-destructive tests, with their drawbacks and difficulties. The main purpose of this research is to establish the integrated approach to evaluating the compressive strength of RC beams by providing the strength distribution visualization. Hence, the combination of the results from the hammer test, compression test, and the two-point load flexural test was taken into account. In this study, a combination of destructive and non-destructive tests was performed on the RC beam specimen. The hammer test results discovered that the concrete strength was distributed randomly with a difference of 20%. However, the strength pattern in the compression zone showed similar results: a lower strength value. The abovementioned results were then validated with the flexural test. By comparing the concrete failure and the strength distribution visualization, the damaged area has a smaller compressive strength than other areas. Thus, the engineers could use the visualization of the strength distribution as a guide in considering repairing options on RC beams more effectively.

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Xie, Bing, Xiao Qiang Wang, and Xiang Xia. "Numerical Simulation of End Friction Effect in Compression Test of Concrete." Applied Mechanics and Materials 174-177 (May 2012): 291–94. http://dx.doi.org/10.4028/www.scientific.net/amm.174-177.291.

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By using PFC2D a numerical specimen of particle aggregates is established. It achieved consistent mechanical parameters of concrete of C35 with the Code for Design of Concrete Structures(GB 50010-2010) by using PFC2D to simulate concrete compression test and it is proved feasible that PFC2D is suitable for simulating compression tests. End friction effect is studied by changing the coefficient of friction of loading plane. The results show that end friction effect will lead to a small cross section in the central and a large cross-section in the end. The compressive strength will increase with the loading plane friction coefficient increases.

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Wang, Qingli, Jie Zhao, and Kuan Peng. "Test on Compressive Performance of Hollow Concrete-Filled Sandwich Circular Steel Tubes Connected by Thread." Metals 13, no. 7 (June 29, 2023): 1207. http://dx.doi.org/10.3390/met13071207.

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The connection method of lengthening the steel tube of hollow concrete-filled sandwich circular steel tubes and threaded connections is proposed. The length, depth and position are the basic parameters. Twelve hollow concrete sandwich circular steel pipes with threaded connections were designed and subjected to axial compression tests. The axial compressive loading–longitudinal compressive displacement curves, axial compressive loading strain of steel tube curves and failure mode of the specimens are analyzed, and the effects of different parameters on the axial compressive-bearing capacity and stiffness of the specimens are studied. The results showed that within the range of parameters studied, the axial compression load–longitudinal compression displacement curves of the specimens were the linear elastic stage and the elastic–plastic stage, which can be divided into a yield-strengthening stage and a decreasing stage. The bearing capacity and strength of the lined threaded connection specimen are not inferior to those of the ordinary specimen or the welded specimen. The bearing capacity and strength of the specimen increase with the increase of the thread length. The bearing capacity and strength of the specimens connected with inner liner screws at the ends are higher than those connected with inner liner bolts at the middle.

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Al-Bahadili, Hussein, and Saif Al-Saab. "Development of a Novel Compressed Index-Query Web Search Engine Model." International Journal of Information Technology and Web Engineering 6, no. 3 (July 2011): 39–56. http://dx.doi.org/10.4018/jitwe.2011070103.

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In this paper, the authors present a description of a new Web search engine model, the compressed index-query (CIQ) Web search engine model. This model incorporates two bit-level compression layers implemented at the back-end processor (server) side, one layer resides after the indexer acting as a second compression layer to generate a double compressed index (index compressor), and the second layer resides after the query parser for query compression (query compressor) to enable bit-level compressed index-query search. The data compression algorithm used in this model is the Hamming codes-based data compression (HCDC) algorithm, which is an asymmetric, lossless, bit-level algorithm permits CIQ search. The different components of the new Web model are implemented in a prototype CIQ test tool (CIQTT), which is used as a test bench to validate the accuracy and integrity of the retrieved data and evaluate the performance of the proposed model. The test results demonstrate that the proposed CIQ model reduces disk space requirements and searching time by more than 24%, and attains a 100% agreement when compared with an uncompressed model.

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Lei, Jianhua, Fan Feng, Shu Xu, Weibin Wen, and Xuhui He. "Study on Mechanical Properties of Modified Polyurethane Concrete at Different Temperatures." Applied Sciences 12, no. 6 (March 21, 2022): 3184. http://dx.doi.org/10.3390/app12063184.

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The objective of the present research was to study the effect of temperature on the mechanical properties, failure mode and uniaxial compression constitutive relationship of a modified polyurethane concrete. A total of 24 cube and 27 prism specimens were fabricated, and the uniformity of the polyurethane concrete was checked. The compressive test, splitting tensile test and static uniaxial compression test were carried out at 0, 15, 40 and 60 °C. The failure mode, cube compressive strength, splitting tensile strength, axial compressive strength, elastic modulus and the compressive stress–strain curves of the modified polyurethane concrete were obtained. Based on the experimental results, a uniaxial compression constitutive model of the modified polyurethane concrete considering temperature characteristics was proposed. The results show that the elastic modulus, cubic compressive strength, splitting tensile strength and axial compressive strength of the modified polyurethane concrete decrease with the increase of temperature, and the peak strain and ultimate strain increase significantly. When the temperature rises from 0 to 60 °C, the cubic compressive strength, splitting tensile strength and axial compressive strength are decreased by 67.1%, 66.4% and 73.3%, respectively. The calculation results of the proposed constitutive model are in good agreement with the test results. The results are expected to guide the application of the modified polyurethane concrete in bridge deck pavement.

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Lee, Jong Woong, Cheol Won Kong, Se Won Eun, Jae Sung Park, Young Soon Jang, Yeong Moo Yi, and Gwang Rae Cho. "Compression Test of Composite Sandwich Panel." Key Engineering Materials 348-349 (September 2007): 605–8. http://dx.doi.org/10.4028/www.scientific.net/kem.348-349.605.

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Composite materials are used in aerospace structures due to their considerable bending stiffness and strength-to-weight ratio. A composite sandwich is composed of a face-sheet and an aluminum core. The face-sheet of the sandwich takes the bending stress and core of sandwich takes the shear stress. A compression test and FEM analysis accomplished about composite sandwich panels that have curvature. The FEM analysis was performed using a commercial code, ANSYS and the compression test was performed until failure occurred in the sandwich panel. A strain gauge and a displacement gauge were used to acquire the data. In this paper, the failure strength and failure mode was checked. Additionally, the results of the test and analysis were compared.

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Neag, Adriana, Qifan Hu, and Tudor Balan. "Accurate plane strain compression test validation." IOP Conference Series: Materials Science and Engineering 1238, no. 1 (May 1, 2022): 012050. http://dx.doi.org/10.1088/1757-899x/1238/1/012050.

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Abstract Large strain characterization of sheet metals has become increasingly important with the generalization of advanced high strength steels, for which the tensile test provides data over a very reduced strain range. Among the numerous alternative characterization tests, the plane strain compression test (PSCT) requires a small amount of material and classical testing machine and acquisition. PSCT was mainly used for hot forming characterization, but recently it has been proved sufficiently accurate for application in cold metal forming. This work provides an in-depth validation of the PSCT by means of the finite element method. When converting the PSCT force-displacement curve into a stress-strain curve (flow curve), several analytical corrections are applied. Several sets of such corrections terms were proposed in the literature, some of which are consistently used by all authors, while others being only used in some papers. The FE simulation of the test was used in order to validate these correction terms and their hypotheses. The originality of the approach is the design of a sequence of test configurations which allow for the individual validation of each and every one of the correction terms concerning the effect of several test parameters. The FE simulations showed that the analytical exploitation of the PSCT provides a very good accuracy. They helped identifying the most suitable correction terms to consider.

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Lee, Dongsoo, and Kaushik Roy. "Viterbi-Based Efficient Test Data Compression." IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems 31, no. 4 (April 2012): 610–19. http://dx.doi.org/10.1109/tcad.2011.2172609.

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Touba, N. A. "Survey of Test Vector Compression Techniques." IEEE Design & Test of Computers 23, no. 4 (April 2006): 294–303. http://dx.doi.org/10.1109/mdt.2006.105.

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Kim, Kee Sup, and Ming Zhang. "Hierarchical Test Compression for SoC Designs." IEEE Design & Test of Computers 25, no. 2 (March 2008): 142–48. http://dx.doi.org/10.1109/mdt.2008.39.

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Journal articles on the topic 'Compression test'

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