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1
Eberemu, Adrian O. "Desiccation Induced Shrinkage of Compacted Tropical Clay Treated with Rice Husk Ash." International Journal of Engineering Research in Africa 6 (November 2011): 45–64. http://dx.doi.org/10.4028/www.scientific.net/jera.6.45.
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Desiccation studies are an integral part of material selection for waste containment systems. Laboratory studies on compacted tropical clay (with illite as the dominant clay mineral sourced from an excavation site) treated with up to 16% rice husk ash (RHA); an agro-industrial waste to evaluate its desiccation induced shrinkage and hence its suitability as a cover material in waste containment systems were carried out. Soil-RHA mixtures were compacted using three compactive efforts at -2, 0, 2 and 4% of optimum moisture content (OMC). Compacted samples, extruded from the compaction mould were allowed to air dry in the laboratory for a 30 day period after which they were subjected to two cycles of wetting and drying. Results show that changes in mass and volumetric shrinkage strain (VSS) were large within the first five days of drying and were affected by the compactive effort. VSS increased with higher moulding water content, water content relative to optimum and RHA treatments. VSS were affected by the compactive effort. Acceptable compaction planes were obtained for up to 12% RHA treatment. After two cycles of wetting and drying, it was observed that the rate of capillary rise within the compacted soil increased with lower compactive effort and higher rice husk ash treatment. Lower amount of cracking was observed in soil specimen with higher rice husk ash treatment and higher cracking in soils with lower rice husk ash content. Increased compactive effort reduced the effect of swelling during wetting; showing the suitability of the material as a cover in municipal waste containment facility and beneficial reuse of this agro waste product.
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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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Mazumdar, Mayajit, and S. K. Rao. "Effect of comparative efforts on sand–asphalt–sulphur mixes." Canadian Journal of Civil Engineering 12, no. 4 (December 1, 1985): 916–19. http://dx.doi.org/10.1139/l85-104.
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The investigation studies the effect that varying the compactive effort has on the Marshall test properties of sand–asphalt–sulphur mixes (S–A–S mixes). An S–A–S mix containing a poorly graded river sand has been chosen for study, the proportions of sand, asphalt, and sulphur being 85:5:10 by weight.Another aspect of this study is to examine the effect of fly ash fines, an industrial waste, on S–A–S mixes. The resulting mix is named S–A–FA–S (sand – asphalt – fly ash – sulphur) and has a percentage composition of 80:5:5:10 by weight.It has been observed that the compactive effort has a definite effect on the Marshall test properties of S–A–S and S–A–FA–S mixes. In both cases, the stability rises initially and then falls with increasing compaction. S–A–FA–S mixes give higher stabilities and lesser air void values than S–A–S mixes at a particular level of compaction. It is concluded that 10 blows of compaction is optimum for S–A–S as well as S–A–FA–S mixes, as the beneficial effect after 10 blows is only marginal.
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Edeh, Joseph E., Adrian O. Eberemu, and James Mzuaor Aburabul. "Effect of Compactive Efforts on the Strength Properties of Groundnut Shell Ash Stabilized Reclaimed Asphalt Pavement." Advanced Materials Research 824 (September 2013): 12–20. http://dx.doi.org/10.4028/www.scientific.net/amr.824.12.
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Large quantities of groundnut shell ash (GSA) are generated from the combustion of groundnut shell, disposed in large quantities on production sites while large volume of reclaimed asphalt pavements (RAP) aggregates are also generated during pavement rehabilitation and reconstruction and disposed along road alignments. This paper presents results of the laboratory evaluation of the effect of compactive efforts on the strength properties of GSA stabilized RAP with a view to determining its suitability as highway pavement material in pavement constructions. The RAP-GSA mixtures were subjected to Reduced British Standard light, RBSL (reduced Proctor); British Standard light, BSL (standard Proctor); West African Standard, WAS and British Standard heavy, BSH (modified Proctor) compactive efforts to determine the compaction characteristics, California bearing ratio (CBR), durability and water absorption characteristics. Test results show that the properties of RAP improved with GSA treatment. The particle grading improved from 99.13 % coarse aggregate and 0.87 % fines, with AASHTO classification of A-1-b for 100 % RAP, and 9.08 % coarse aggregate and 90.92 % fines, with AASHTO classification of A-4 for 100 % GSA to 15.6691.72 % coarse aggregate and 8.2884.32 % fines, with AASHTO classification in the range A-4 (silty soil) to A-1-a (granular materials), for the various RAP-GSA mixes. Maximum dry density (MDD) decreased while the optimum moisture content (OMC) increased with higher GSA content in the RAP + GSA mixes and with decreased compactive effort from BSH to RBSL. Optimum CBR values of 35.1% (unsoaked) and 44.1% (soaked) recorded for 90% RAP + 10% GSA mix achieved with BSH compactive effort, satisfied the durability requirements with insignificant expansion and water absorption and can be used as subbase material in flexible pavements construction. This research provides the results of evaluation of the effect of compactive efforts on the strength properties of GSA stabilized RAP as highway construction material, as it is based on CBR determination. Further work may be encouraged to assess resilient modulus of this material under cyclic load.
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Rotimi, Oluremi Johnson, Bamigboye Gideon Olukunle, Afolayan Olaniyi Diran, B. Iyanda Olayinka, and A. Bello Usman. "Strength Enhancement Potential of Spent Calcium Carbide on Fine Grained Lateritic Soil." Journal of Solid Waste Technology and Management 47, no. 1 (February 1, 2021): 156–63. http://dx.doi.org/10.5276/jswtm/2021.156.
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Effect of spent calcium carbide (SCC) on index and strength properties of lateritic soil at differ- ent compactive efforts was assessed in this study as potential means of improving the geotechnical properties of the subsoil as well as disposing of SCC as waste. SCC was admixed with the soil using 0 to 10 % by dry weight of soil at an incremental rate of 2%. The following tests were carried out on the samples: specific gravity, Atterberg limit, particle size distribution, compaction, and California bearing ratio (CBR). Compaction and California Bearing Ratio (CBR) tests were carried out using British Standard light (BSL), West African Standard (WAS), and British Standard heavy (BSH) on both the natural and stabilized soil samples. From the investigation, atterberg limits show a reduction in the plasticity index with increasing content of SCC. The maximum dry density of the soil decreased with increasing SCC content and increased with an increase in compactive energies (BSL<WAS<BSH), while and optimum moisture content (OMC) increased correspondingly. Also, soaked and unsoaked CBR values of the stabilized lateritic soil showed an increase in strength with higher compactive effort, and SCC content up to 4% SCC addition and after that decreased in value. Based on these results, spent calcium carbide improved the geotechnical properties of this lateritic soil, and 4% SCC is recommended for its stabilization as subgrade material for pavement construction, thereby serving as an effective method of disposing SCC towards promoting a green and sustainable environment.
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Oke, J. A., N. O. Obaji, and K. J. Osinubi. "Oil palm empty fruit bunch ash stabilized laterite as a fill material for low-volume pavement." Nigerian Journal of Technology 39, no. 3 (September 16, 2020): 721–31. http://dx.doi.org/10.4314/njt.v39i3.10.
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A reddish-brown laterite was treated with up to 14 % oil palm empty fruit bunch ash (EFBA) by dry weight of soil and compacted with the British Standard light, BSL (or Standard Proctor) compactive effort. Index, compaction, strength and durability tests as well as microanalysis of the natural and stabilized specimens were carried out. The index, compaction characteristics (maximum dry density, MDD and optimum moisture content, OMC) and strength properties (California bearing ratio, CBR and unconfined compressive strength, UCS) were improved with higher EFBA treatment. Peak un-soaked and soaked CBR values of 70.0 and 45.0 %, as well as peak UCS strengths of 253.0, 462.0 and 577 kN/m2 at 7, 14 and 28 days curing were recorded at 8 % EFBA content. Based on the CBR specification specified in the Nigerian General Specifications, the laterite optimally treated with 8 % EFBA compacted with the BSL compactive effort can be used as a fill material in the construction of low-volume traffic pavement. The benefit of the EFBA application is primarily the reduction of the adverse environmental impact of the oil palm empty fruit bunch waste.
Keywords: California bearing ratio, durability, laterite, oil palm empty fruit bunch ash, microanalysis, stabilization
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Ogundipe, Olumide Moses, Jonathan Segun Adekanmi, Olufunke Olanike Akinkurolere, and Peter Olu Ale. "Effect of Compactive Efforts on Strength of Laterites Stabilized with Sawdust Ash." Civil Engineering Journal 5, no. 11 (November 1, 2019): 2502–14. http://dx.doi.org/10.28991/cej-2019-03091428.
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This study investigates the effects of different compactive efforts on the strength of laterites stabilized with sawdust ash (SDA). Laterites in the categories of A-7-5 and A-7-6 were considered because they are not suitable in the natural states as subgrade materials. The geotechnical properties of the laterites in their natural states were determined. The sawdust was burnt and sieved through 600micron. The sawdust ash (at 2%, 4%, 6%, 8% and 10%) was added to the laterites and the atterberg limits were determined, while the California bearing ratio and Unconfined compression test were determined using three compactive efforts (596, 1192 and 2682KN-m/m3).It was generally observed that the maximum dry densities of the natural and stabilised laterites increase with increase in the compactive efforts, while the optimum moisture contents reduce. The plasticity indices of the laterites increased with the addition of SDA. The optimum values of the MDDs (2006 and 1878 kg/m3) were observed at 4% and 6% SDA of 2682 kN-m/m3 compactive effort for samples A and B, respectively. The soaked and unsoaked CBR values of the soils at natural state are 4.89 and 16.33%, and 3.4 and 5.62% for samples A and B, respectively. The results indicate that the higher the compactive efforts, the higher the CBR values of the two samples. Increase in SDA contents of soil samples A and B showed a non-predictable trend on their CBR values. The Unconfined Compressive Strength values at natural and treated states fell below the requirements. Generally, it was found that the use of sawdust ash alone as stabilizer was not effective. Therefore, it was concluded that future studies should consider the use of the sawdust ash in combination with cement or lime.
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Ochepo, J. "Effect of Rice Husk Ash on the Hydraulic Conductivity and Unconfined Compressive Strength of Compacted Bentonite Enhanced Waste Foundry Sand." LAUTECH Journal of Civil and Environmental Studies 5, no. 1 (September 27, 2020): 85–96. http://dx.doi.org/10.36108/laujoces/0202/50(0190).
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A laboratory study of the hydraulic conductivity, (HC), and unconfined compressive strength, (UCS), of compacted bentonite enhanced waste foundry sand (BEWFS) treated with rice husk ash, (RHA) for possible use as liner material is presented. The bentonite enhanced waste foundry sand, BEWFS, was obtained by blending waste foundry sand (WFS) with 12% bentonite by weight of the WFS and mixing the resulting blend thoroughly to obtain a homogenous mix. RHA was added to the BEWFS in increment of 2, 4, 6, 8 and 10% respectively of the dry weight of the BEWFS. The entire blended material was thoroughly mix together to obtain sample with different content of RHA. Index tests, compaction, UCS and HC tests were carried out on the blended materials to determine the effect of RHA on the behaviour of the BEWFS. HC as well as UCS of the materials were study using three compactive efforts of British standard light, (BSLC), West African standard, (WASC) and British standard heavy, (BSHC) compactive efforts respectively. The results obtained show that addition of RHA to BEWFS affected the index properties of the material marginally where the liquid limit increased to 35 from 32 %, plastic limit reduced from 12 to 11% and plasticity index increased from 20 to 25% respectively. The HC of the material was found to increase slightly from 6.28 x 10-08 to 3.90 x 10-08, 2.64 x 10-09 to 2.07 x 10-08 and 8.55 x 10-11 to 1.83 x 10-10 m/s with addition of up to 10 % RHA content and compacted at BSLC, WASC and BSHC respectively. Similarly, the UCS was found to increase to peak values of 177.22, 288.48 and 454.26 kN/m2 at same RHA content and compactive efforts. The implication of this result is that the addition of RHA up to 10% to BEWFS slightly increase the HC but does not compromise it while the strength gain in term of UCS can be said to compensate for the slight lost in HC. It is recommended that BEWFS treated with between 8 to 10% RHA content and compacted at BSHC compactive effort can be applied as liner in engineered waste containment system.
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Yusuf, Umar Sa’eed, Matawal Danladi Slim, and Elinwa Augustine Uchechukwu. "Hydraulic Conductivity of Compacted Laterite Treated with Iron Ore Tailings." Advances in Civil Engineering 2016 (2016): 1–8. http://dx.doi.org/10.1155/2016/4275736.
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The objective of this study was to investigate the effect of iron ore tailings (IOT) on hydraulic conductivity of compacted laterite. The IOT conforms to ASTM C 618-15 Type F designations. In the present study, soil was admixed with 0–20% IOT and compacted at moulding water content ranging from 10 to 25% using four types of compactive efforts. Hydraulic conductivities of the compacted soil-IOT mixtures were determined using deionized water and municipal solid waste leachate as the permeant fluids, respectively. Deionized water was the reference permeant fluid. Results of this study showed that hydraulic conductivity decreased with increase in IOT content as a result of improvement in mechanical properties of the soil. Permeation of the soil-IOT mixtures with leachate caused the hydraulic conductivity to drop to less than 1 × 10−9 m/s especially at higher compactive efforts. Also, bioclogging of the soil pores due to accumulation of biomass from bacteria and yeast present in the leachate tends to significantly reduce the hydraulic conductivity. From an economic point of view, it has been found from the results of this study that soil specimens treated with up to 20% IOT and compacted at the British Standard Light (BSL) compactive effort met the maximum regulatory hydraulic conductivity of less than or equal to 1 × 10−9 m/s for hydraulic barrier system.
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Eberemu, Adrian O., Agapitus A. Amadi, and Joseph E. Edeh. "Hydraulic Conductivity of Compacted Tropical Clay Treated with Rice Husk Ash." Advanced Materials Research 367 (October 2011): 63–71. http://dx.doi.org/10.4028/www.scientific.net/amr.367.63.
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Laboratory study on compacted tropical clay treated with up to 16% rice husk ash (RHA), an agro-industrial waste; to evaluate its hydraulic properties and hence its suitability in waste containment systems was carried out. Soil-RHA mixtures were compacted using standard Proctor, West African Standard and modified Proctor efforts at-2, 0, 2 and 4% of optimum moisture content (OMC). Compacted samples were permeated and the hydraulic behaviour of the material was examined considering the effects of moulding water content, water content relative to optimum, dry density and RHA contents. Results showed decreasing hydraulic conductivity with increasing moulding water content and compactive efforts; it also varied greatly between the dry and wet side of optimum decreasing towards the wet side. Hydraulic conductivity generally decreased with increased dry density for all effort. Hydraulic conductivity increased with rice husk ash treatment at the OMC; but were within recommended values of 1 x 10-7 cm/s for up to 8% rice husk ash treatment irrespective of the compactive effort used. This shows the suitability of the material as a hydraulic barrier in waste containment systems for up to 8% rice husk ash treatment and beneficial reuse of this agro-industrial waste product.
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Joel, M., and LJ Joseph. "Effect of compactive effort on strength indices of laterite treated with calcium carbide waste." Global Journal of Engineering Research 14, no. 1 (December 15, 2015): 47. http://dx.doi.org/10.4314/gjer.v14i1.6.
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Nwaiwu, Charles, Samson Mshelia, and Joshua Durkwa. "Compactive effort influence on properties of quarry dust-black cotton soil mixtures." International Journal of Geotechnical Engineering 6, no. 1 (January 2012): 91–101. http://dx.doi.org/10.3328/ijge.2012.06.01.91-101.
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Kleven, Jay R., Tuncer B. Edil, and Craig H. Benson. "Evaluation of Excess Foundry System Sands for Use as Subbase Material." Transportation Research Record: Journal of the Transportation Research Board 1714, no. 1 (January 2000): 40–48. http://dx.doi.org/10.3141/1714-06.
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Earthwork associated with highway construction provides an opportunity for high-volume reuse of excess system sands (ESS) discarded by the foundry industry. California bearing ratio (CBR), unconfined compressive strength, and resilient modulus tests were conducted on 13 ESS, one base sand, and two reference materials. Tests were conducted on specimens prepared dry of optimum, wet of optimum, and at optimum water content with standard and modified Proctor compaction effort. Results of these tests were used to identify characteristic engineering properties of ESS, appropriate compaction conditions for ESS when used as subbase, and empirical equations that can be used to predict the engineering properties of ESS based on index properties. Results of the tests indicate that ESS classify as SP, SM, or SP-SM (A-2-4 or A-3 in AASHTO) and should be compacted dry or at optimum water content and, if possible, with higher compactive effort. The CBR of the ESS ranged from 4 to 40 and averaged 20 when compacted with standard effort at optimum water content. Swell during the soaking portion of the CBR tests was small for all ESS. ESS compacted at optimum water content with standard effort had unconfined compressive strengths ranging from 71 to 190 kPa. Resilient moduli of the ESS were similar to that of a reference subbase material but smaller than a reference base material. A power function model in terms of bulk stress described resilient moduli of the ESS well.
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Onyelowe, Kennedy Chibuzor, Duc Bui Van, Mohammed Oludare Idrees, Michael E. Onyia, Lam Dao-Phuc, Favour Deborah A. Onyelowe, Talal Amhadi, et al. "An Experimental Study on Compaction Behavior Of Lateritic Soils Treated with Quarry Dust Based Geopolymer Cement." Journal of Solid Waste Technology and Management 47, no. 1 (February 1, 2021): 104–19. http://dx.doi.org/10.5276/jswtm/2021.104.
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Due to the scarcity of well-graded gravel materials, lateritic soils are widely used for road construction in tropic areas. However, lateritic soils often do not meet the strict requirement for subgrade and need to be improved to be used as construction material. Among several approaches used to enhance the engineering properties of lateritic soils, the use of industrial waste materials, such as fly ash, granulated blast furnace slag, is of particular interest to the construction industry as a potential replacement material for Portland cement in soil stabilization. Meanwhile, some effort has been made to study the use of quarry dust in stabilizing lateritic soils. The present work aims at assessing the compaction characteristics of three different types of lateritic soils, treated with quarry dust based geopolymer cement. A systematic study by varying the proportion of geopolymer cement was carried out. Test results show that the soil dry density substantially increased while the corresponding optimal moisture content decreased with the amount of geopolymer cement under varying compactive effort.
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Sreelekshmypillai, G., and P. Vinod. "Prediction of CBR value of fine grained soils at any rational compactive effort." International Journal of Geotechnical Engineering 13, no. 6 (September 25, 2017): 560–65. http://dx.doi.org/10.1080/19386362.2017.1374495.
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Vinod, P., and G. Sreelekshmy Pillai. "Toughness Limit: A Useful Index Property for Prediction of Compaction Parameters of Fine Grained Soils at Any Rational Compactive Effort." Indian Geotechnical Journal 47, no. 1 (June 11, 2016): 107–14. http://dx.doi.org/10.1007/s40098-016-0194-6.
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Henderson, C., A. Levett, and D. Lisle. "The effects of soil water content and bulk density on the compactibility and soil penetration resistance of some Western Australian sandy soils." Soil Research 26, no. 2 (1988): 391. http://dx.doi.org/10.1071/sr9880391.
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Quantitative models to predict the effects of soil compaction on wheat yields are being developed for the northern sandplains of Western Australia. An understanding of the relationships between soil water content (W), bulk density (p), compactibility and soil penetration resistance (P) is required. Thirteen subsoils from W.A. sandplain soils were tested for compactibility. As the amounts of very coarse sand or clay in the soil increased, the maximum density (�max.) achieved with a standard compactive effort also increased, while the critical soil water content (Wcrit,.) for maximum compactibility declined. The effects of p and W on P were investigated for five of the soils. The value of P was only slightly affected as W was reduced to less than 70% of the field capacity water content. As the soils were dried further, P increased exponentially. At all water contents, an increase in p was found to markedly increase P. Particle size distribution could be used to predict �max. and Wcrit., but could not be related to the effects of changes in p and W on P. The implications for the measurement and effects of soil compaction in the field are discussed.
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Zoladz, Glen V., Timothy J. McGrath, and Ernest T. Selig. "Laboratory Tests of Buried Pipe Installation Procedures." Transportation Research Record: Journal of the Transportation Research Board 1541, no. 1 (January 1996): 86–96. http://dx.doi.org/10.1177/0361198196154100111.
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Laboratory testing of buried pipe was conducted to evaluate the pipe-soil interactions that take place as pipes are backfilled. The program consisted of 25 tests with metal, plastic, or concrete pipe. In addition to pipe type, test variables included trench conditions, backfill material, compaction method, haunching effort, and bedding condition. The tests were conducted in an indoor test facility designed to allow for the installation of pipe in a realistic manner. Pipe and soil behavior were monitored during installation, and measurements included pipe deflections, pipe strain, pipe-soil interface pressures, soil density, soil strength, and horizontal soil stresses. Backfill was placed to at least 150 mm above the spring line to observe the effects in the important haunch zone. Ten of the tests were continued until the backfill was at least 300 mm over the pipe. The results indicated significant variations in pipe behavior because of installation practices. The wider trench produced greater upward deflections during sidefill compaction. The rammer compactor was the most effective means of achieving high backfill density and stiffness, forcing backfill into the haunch zone, and developing beneficial lateral soil stresses at the sides of the pipe. Installation in trenches with walls of soft materials results in lower lateral pressures and higher invert pressures on the pipe. The coarser-grained backfill material achieved suitable soil unit weight and stiffness with less compactive energy than the finer-grained material. The haunching effort provided improved pipe support in the lower haunch zone.
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Wu, Guo Xiong, Liang Zhang, and Li Juan Luo. "Cement-Gravel Piles for Highway Soft Soil Settlement Treatment in Yunnan Province." Advanced Materials Research 594-597 (November 2012): 1367–71. http://dx.doi.org/10.4028/www.scientific.net/amr.594-597.1367.
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Highway in Yunnan Province, China, was known to suffer from local settlement due to the soft red soil foundations. This paper proposed cement-gravel piles to treat the settled foundations before paving the surface layer in highway repair and maintenance, in order to enhance the overall highway bearing capacity. Finite element software ANSYS was used to study the effect of cement-gravel piles on soft soil reinforcement and water reduction. The cement-gravel pile design parameters (9 to 10m for pile length, 1.2m to1.6m for pile spacing and 0.8m for pile diameter)are determined for different fill height, compactive effort and settlement magnitude. This research will provide helpful guidance to highway repair and maintenance of highway built in soft soil regions.
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Díaz-Zorita, M., J. H. Grove, and E. Perfect. "Soil Fragment Size Distribution and Compactive Effort Effects on Maize Root Seedling Elongation in Moist Soil." Crop Science 45, no. 4 (July 2005): 1417–26. http://dx.doi.org/10.2135/cropsci2003.0670.
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Edeh, Joseph E., Adrian O. Eberemu, and Onah Agnes. "Lateritic Soil Stabilization of Reclaimed Asphalt Pavement as Flexible Highway Pavement Materials." Advanced Materials Research 367 (October 2011): 3–11. http://dx.doi.org/10.4028/www.scientific.net/amr.367.3.
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This paper presents the results of the laboratory evaluation of the characteristics of lateritic soil stabilized reclaimed asphalt pavements (RAP), using 0 – 2% cement, subjected to British Standard Light (BSL) compactive effort to determine their index, compaction and california bearing ratio (CBR) results. The result of the laboratory tests show that the properties of RAP improved when stabilized with lateritic soil, using up to 2% cement. The particle size distribution improved from poorly graded sandy GRAVELLY material for 100% lateritic soil and very sandy GRAVELLY material, to the gradation described as well graded very sandy GRAVELLY material for lateritic soil stabilized RAP, using up to 2% cement. The CBR results obtained from the study show that using the Nigerian General Specifications, 180% CBR value criterion, the maximum CBR of 55% (soaked) for the mix proportion; 40% Laterite + 58% RAP + 2% Cement for A-2-7(2) soil prescribed by the latter is not adequate for stabilization of base coarse. However, judging by the 24-hour strength gain from 17.9 (unsoaked) to 55% (soaked) CBR values, the material can be used as subgrade and subbase materials.
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Eberemu, Adrian O., Deborah I. Omajali, and Zubairu Abdulhamid. "Effect of Compactive Effort and Curing Period on the Compressibility Characteristics of Tropical Black Clay Treated with Rice Husk Ash." Geotechnical and Geological Engineering 34, no. 1 (November 14, 2015): 313–22. http://dx.doi.org/10.1007/s10706-015-9946-9.
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Amadi, Agapitus A., and Adrian O. Eberemu. "Performance of Cement Kiln Dust in Stabilizing Lateritic Soil Contaminated with Organic Chemicals." Advanced Materials Research 367 (October 2011): 41–47. http://dx.doi.org/10.4028/www.scientific.net/amr.367.41.
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Accidental or deliberate operational discharges of organic chemicals or wastes containing organic chemicals induce geochemical reactions with resultant adverse effects on basic geotechnical properties of the soil. To utilize soil materials from such sites for engineering construction or as foundation soil, stabilization must be carried out. In this study, cement kiln dust (CKD) was applied to lateritic soil contaminated with three different types of commonly occurring organic chemicals namely benzene, ethanol and kerosene to evaluate the restoration and improvements in the engineering properties. Contamination was simulated in the laboratory by adding known quantities (2.5, 5, 7.5 and 10%) of each of the chemicals separately to lateritic soil samples and allowed to air dry for 14 days before stabilizing with 10% CKD. Performance was evaluated on Atterberg limits, compaction characteristics, strength properties and hydraulic conductivity of the contaminated soil. Strength and hydraulic conductivity specimens were compacted with British Standard Light (BSL) compactive effort at predetermined optimum moisture content. Results showed that the simultaneous effects of the cementing and pozzolanic action of the CKD rejuvenated the geotechnical properties of the soil, in most cases comparable to the properties at the original pristine condition. Studies on durability and long term competent performance of the stabilized contaminated soil specimens is in progress.
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Osinubi, K. J., G. Moses, and A. S. Liman. "The Influence of Compactive Effort on Compacted Lateritic Soil Treated with Cement Kiln Dust as Hydraulic Barrier Material." Geotechnical and Geological Engineering 33, no. 3 (December 27, 2014): 523–35. http://dx.doi.org/10.1007/s10706-014-9837-5.
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Ikeagwuani, C. C., D. C. Nwonu, C. Eze, and I. Onuoha. "Investigation of shear strength parameters and effect of different compactive effort on lateritic soil stabilized with coconut husk ash and lime." Nigerian Journal of Technology 36, no. 4 (January 15, 2018): 1016. http://dx.doi.org/10.4314/njt.v36i4.4.
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Ishola, K., O. A. Olawuyi, P. Yohanna, A. A. Bello, R. O. Sani, and O. O. Akin. "Reliability Evaluation of Compaction Water Content of Plantain Peel Ash Treated Lateritic Soil." Nigerian Journal of Technological Development 18, no. 1 (June 24, 2021): 47–54. http://dx.doi.org/10.4314/njtd.v18i1.7.
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A first-order reliability method (FORM)was employed to assess the compaction water content, CWC (i.e optimum moisture content) of residual lateritic soil mixed with plantain peel ash (PPA) and compacted with British Standard Light (BSL)and British Standard Heavy (BSH)energies, for flexible pavement applications. A Multi-linear regression model was generated from values obtained via laboratory tests using Mini-tab R15 software, which served as a performance function that was applied for the analysis. Using the regression models for CWC, established distributions for the relevant soil factors, safety index (SI) was computed using CWC as a dependent factor and the soil factors Plantain Peel Ash (PPA); Plasticity Index (PI); Percentage File (PF); Specific Gravity (Gs) and Compactive Effort (CE)as self-determining factors). The results revealed that the safety index is sensitive to changeability in the soil factors. Outcome from the analysis show that Gs and CE are greatly affected by alteration in the coefficient of variation (COV), and so it is essential to control Gs and CE in lateritic soil–PPA mixes in road pavements. From the safety index values it reveals that PPA content has a minimal consequence as its value virtually remained constant at all COV used. Stochastically, lateritic soil mixed with PPA produces an acceptable safety index value of 1.0, as mentioned by the Nordic Committee on Building Regulation (NCBR) at 10% COV for BSH of compaction water content only. Therefore a more effective additive such as cement, lime, or bitumen is recommended for modeling CWC of lateritic soil-PPA mixes for road pavement at 10–100% series of COV.
Keywords: Coefficient of variation; compaction water content; lateritic soil; plantain peel ash; reliability index
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Sims, John E., Derek Elsworth, and John A. Cherry. "Stress-dependent flow through fractured clay till: a laboratory study." Canadian Geotechnical Journal 33, no. 3 (July 2, 1996): 449–57. http://dx.doi.org/10.1139/t96-066.
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Stress-dependent hydraulic conductivities of weathered fractured clay till were measured in a flexible-wall permeameter. Measured conductivities were in the range 107 to 108 cm/s, of the same order as the clay matrix (108 cm/s), and representing equivalent hydraulic apertures in the range 05 μm. In general, the isolated fractures exhibited strongly nonlinear closure characteristics and hysteric behaviour under stress reversal. Some fracture samples exhibited only weak stress dependency, representing observable features of only nominal conductivity. Results of the investigations suggest fractures are closed to residuel aperture for an overburden load of the order of 12 m, this defining an effective closure depth and the degree of maximum useful compactive effort that might be applied to "seal" fractures and reduce fluid migration. Key words: fracture permeability, till, stress permeability, landfills.
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Amadi, Agapitus A., and K. J. Osinubi. "Assessment of Bentonite Influence on Hydraulic Conductivity of Lateritic Soil." International Journal of Engineering Research in Africa 3 (November 2010): 84–93. http://dx.doi.org/10.4028/www.scientific.net/jera.3.84.
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Lateritic soils are pedogenic surface deposits which occur in vast areas of tropical and subtropical regions of the world and find use as construction material in diverse civil engineering aspects. But, the predominance of kaolinitic 1:1 lattice clay mineral and coating of the clayey constituents with sesquioxides limits the ability of the soil from achieving very low hydraulic conductivity, (k) required for some geotechnical/geoenvironmental structures. The present study investigates the influence of low percent bentonite on the hydraulic conductivity of a residually derived lateritic soil. Accordingly, the test programme involved specimens of lateritic soil - bentonite mixtures containing 0, 2.5, 5, 7.5 and 10% bentonite (by dry weight of soil) prepared at different compaction states (optimum, dry and wet of optimum content), compacted with British Standard Heavy, (BSH) compactive effort and permeated in compaction mould permeameter using falling head test method. Results indicate that reductions in hydraulic conductivity values ranged from 1 x 10-9 to 6.79 x 10-11 m/s (i.e. two orders of magnitude) as the percentage of bentonite increased from 0 to 10%. Soil mixtures with up to 5% bentonite content recorded the lowest k values at 2% wet of optimum moisture content, beyond which an increase in k followed. For soil mixtures containing 7.5 and 10% bentonite, a continuous decrease in k was observed. Furthermore, a non – linear relationship between log k and bentonite content was established. These results met or exceeded specification requirements for the aforementioned structures which therefore suggest that the potentials of lateritic soils as a geomaterial for the construction of hydraulic structures can be fully realized when treated with bentonite.
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Oluremi, Johnson R., Adrian O. Eberemu, Stephen T. Ijimdiya, and Kolawole J. Osinubi. "Lateritic Soil Treated with Waste Wood Ash As Liner in Landfill Construction." Environmental and Engineering Geoscience 25, no. 2 (May 1, 2019): 127–39. http://dx.doi.org/10.2113/eeg-2023.
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ABSTRACTInherent variability in engineering properties of lateritic soil in relation to its plasticity, permeability, strength, workability, and natural moisture content, has made it an unpredictable material for use in civil engineering works, resulting in the need for its treatment by stabilization. A lateritic soil classified as A-6(6) and CL, according to American Association of State Highway and Transportation Officials and Unified Soil Classification System of ASTM (2011), was treated with up to 10 percent waste wood ash (WWA). Compaction was carried out using four energies, namely, reduced British Standard light, British Standard light (BSL), West African Standard, and British Standard heavy, on samples, which were then examined for hydraulic conductivity, volumetric shrinkage, and unconfined compressive strength as major criteria for use as liner and for the development of acceptable zones. Specimens with 4 percent WWA content compacted with a minimum BSL energy satisfied the maximum hydraulic conductivity (k) value of 1 × 10−9 m/s, maximum volumetric shrinkage strain of 4 percent, and minimum unconfined compressive strength value of 200 kN/m2 required for use as liner in engineered landfills. The overall acceptable zone was enlarged for up to 4 percent WWA content, thereby accommodating higher moulding water content, but the minimum compactive effort required to achieve it became reduced. The beneficial treatment of lateritic soil with up to 4 percent WWA will perform satisfactorily as liner and covers in waste containment application and will minimize the pollution and environmental impact of wood waste disposal.
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Ling, Felix N. L., Khairul Anuar Kassim, Ahmad Tarmizi Abdul Karim, and S. C. Ho. "Evaluation of Contributing Factors on Strength Development of Lime Stabilized Artificial Organic Soils Using Statistical Design of Experiment Approach." Advanced Materials Research 905 (April 2014): 362–68. http://dx.doi.org/10.4028/www.scientific.net/amr.905.362.
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Lime is widely used as chemical stabilizer in soft soil stabilization. However, lime is reported to be less effective when dealing with organic soil. It is believed that the organic matter in the soil will retard the pozzolanic reaction which is responsible for strength enhancement. The heterogeneity nature of the organic matter in the soil makes the study complicated and reduced the repeatability of the test results. Hence, artificial organic soil with known organic matter and content are preferred by researchers when repeatability of the test results are required in determining the influential effect of each contribution factor. Various factors such as additive contents, effect of aging (curing periods), curing temperature, density of materials and moisture content are reported by previous researchers as the potential contributing factors towards the strength development. It is believed that the interaction of the factors also will contribute to the strength enhancement. Hence, this study is carried out to evaluate the contributing factors and its interactions on strength development of artificial organic soils with known type and contents of organic matter. Statistical design of experiment (DOE) approach was utilized to evaluate the factors and its interaction on the strength development of lime stabilized artificial organic soils by using commercial statistics package. Three main factors were investigated: effect of organic content, effect of curing periods, and effect of additive, while other factors namely curing temperature, molding water content, types of compaction and compactive effort were keep constant through controlled experiments. Processed kaolin (inorganic material) is mixed with humic acid (organic matter) to simulate the organic soil which comprised of inorganic soil and organic matter. The density of the soil specimen and its moisture content were recorded before and after the curing process. General Linear Model (GLM) was utilized to determine the significance of the main factors, two-factor interactions, and three factor interactions. The significance factors and interactions were utilized in multiple regression analysis to develop the strength prediction model which can be utilized to predict the strength of stabilized materials within the inference space defined by the experiment.
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Edeh, Joseph E., Manasseh Joel, and James Mzuaor Aburabul. "Groundnut Shell Ash Stabilized Reclaimed Asphalt Pavement, as Pavement Material." Advanced Materials Research 824 (September 2013): 3–11. http://dx.doi.org/10.4028/www.scientific.net/amr.824.3.
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Large volume of reclaimed asphalt pavements (RAP) aggregates are generated during pavement rehabilitation and reconstruction and disposed along road alignment while large quantities of groundnut shell ash (GSA) are generated from the combustion of groundnut shell and also disposed in large quantities on production sites. This paper presents results of the laboratory evaluation of the characteristics of GSA stabilized RAP with a view to determining its suitability for use as highway pavement material in flexible pavements construction. The RAP-GSA mixtures were subjected to British standard light (BSL) (standard Proctor) compactive effort to determine the compaction characteristics and California bearing ratio (CBR). Test results show that the properties of RAP improved with GSA treatment. The particle grading improved from 99.13% coarse aggregate and 0.87% fines, with AASHTO classification of A-1-b for 100% RAP and 9.08% coarse aggregate and 90.92% fines, with AASHTO classification of A-4 for 100% GSA to 15.6691.72% coarse aggregate and 8.2884.32% fines, with AASHTO classification in the range A-4 (silty soil) to A-1-a [granular material, for the various RAP-GSA mixes. Maximum dry density (MDD) decreased while the optimum moisture content (OMC) increased with higher GSA content in the RAP + GSA mixes. Optimum CBR values of 22.2% (unsoaked) and 18.3% (soaked) were recorded for 80% RAP + 20% GSA and 90% RAP + 10% GSA mixes, respectively. This optimum mixes satisfied durability requirement with insignificant water absorption and can be used as subgrade material in flexible pavements. This research provides the results to the evaluation of GSA stabilized RAP as highway construction material, as it is based on CBR determination. Further work may be encouraged to assess resilient modulus of this material under cyclic load.
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Oluremi, Johnson R., Rafat Siddique, and Ekundayo P. Adeboje. "Stabilization Potential of Cement Kiln Dust Treated Lateritic Soil ." International Journal of Engineering Research in Africa 23 (April 2016): 52–63. http://dx.doi.org/10.4028/www.scientific.net/jera.23.52.
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A dark reddish-brown lateritic soil collected from existing borrow pit abandoned by Reynold Construction Company Ltd behind New WAZOBIA Market on Latitude 08008′N and Longitude 04014′E along Ogbomoso-Ilorin Express road, Ogbomoso, Oyo State. Nigeria was treated with cement kiln dust (CKD), a by-product of long wet kiln, obtained from West African Portland Cement Organisation (WAPCO), Ewekoro, Ogun State, Nigeria, under varying moulding water content.The results show gradual reduction in the plasticity index of the samples, decrease in the maximum dry densities (MDD) with corresponding increase in the optimum moisture contents (OMC) of the treated soil samples. The unconfined compressive strength (UCS) of the treated samples increases with both increase in the treatment content as well as compactive effort from British Standard (BS) to West African Standard (WAS) however, there was reduction in the UCS with varying moulding water content as the water content increases and decreases relative to optimum moisture content. The maximum UCS was obtained at optimum moisture content.Cement kiln dust though regarded as waste can therefore serve as potential material in the stabilization of the lateritic soil when compacted at moisture content within its OMC.
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Amer, Nader, Norbert Delatte, and Chris Storey. "Using Gyratory Compaction to Investigate Density and Mechanical Properties of Roller-Compacted Concrete." Transportation Research Record: Journal of the Transportation Research Board 1834, no. 1 (January 2003): 77–84. http://dx.doi.org/10.3141/1834-10.
Full textAbstract:
Roller-compacted concrete (RCC) is a durable, economical, low-maintenance material for low-speed, heavy-duty paving applications, including industrial and multimodal pavements. However, it is difficult to prepare laboratory specimens to represent field performance, because RCC is very dry and requires considerable compactive effort to achieve field densities. The gyratory compactor, commonly used to prepare hot-mix asphalt specimens, may be used in preparing specimens for laboratory testing. Materials and mix designs from two industrial paving projects were used to prepare specimens for comparison. Field results indicated that the gyratory compactor produced specimens with mechanical properties consistent with those achieved in the field. Specimens had high strength and consistent density, with low variability. The gyratory compactor may be used to replace other methods presently used for preparing RCC specimens such as the modified Vebe apparatus, the vibrating table, and the vibrating hammer. These methods have limitations that may be overcome with the gyratory compactor because of its consistency and its compatibility with field results. The effects of density and specimen aspect ratio on compressive and splitting tensile strength were investigated. The number of gyrations applied to the specimen may be used to duplicate the desired field density. For the industrial pavements investigated, approximately 60 gyrations accurately replicated field conditions.
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Kandhal, Prithvi S., Kee Y. Foo, and Rajib B. Mallick. "Critical Review of Voids in Mineral Aggregate Requirements in Superpave." Transportation Research Record: Journal of the Transportation Research Board 1609, no. 1 (January 1998): 21–27. http://dx.doi.org/10.3141/1609-03.
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Reports of increased difficulties in meeting the minimum voids in mineral aggregate (VMA) requirements have surfaced with the recent use of Superpave volumetric mix design. The low VMA of Superpave mixes generally can be contributed to the increased compactive effort by the Superpave gyratory compactor. This has led to the increased use of coarser asphalt mixes (gradations near the lower control points). However, the minimum VMA requirements in Superpave volumetric mix design for these coarse mixes are the same as those developed for the dense mixes designed by the Marshall method. Literature review has indicated that the rationale behind the minimum VMA requirement was to incorporate at least a minimum permissible asphalt content into the mix to ensure its durability. Studies have shown that asphalt mix durability is directly related to asphalt film thickness. Therefore, the minimum VMA should be based on the minimum desirable asphalt film thickness instead of on a minimum asphalt content because the latter will be different for mixes with different gradations. Mixes with coarse gradation (and, therefore, a low surface area) have difficulty meeting the minimum VMA requirement based on minimum asphalt content despite thick asphalt films. A rational approach based on a minimum asphalt film thickness has been proposed and validated. The film thickness approach represents a more direct, equitable, and appropriate method of ensuring asphalt mix durability, and it encompasses various mix gradations.
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Watson, Donald E., Kathryn Ann Moore, Kevin Williams, and L. Allen Cooley. "Refinement of New-Generation Open-Graded Friction Course Mix Design." Transportation Research Record: Journal of the Transportation Research Board 1832, no. 1 (January 2003): 78–85. http://dx.doi.org/10.3141/1832-10.
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Open-graded friction course (OGFC) has been used in the United States for more than 50 years. In 2000, National Center for Asphalt Technology (NCAT) research led to a recommended mix design procedure for a new-generation OGFC, but the work involved only one aggregate source. Therefore, NCAT is in the process of refining this design procedure to ensure that it is applicable to other aggregate types used in surface mixes throughout the United States. The objectives of NCAT's current research are to refine and field validate the new-generation OGFC mix design procedure. This work has led to several experiments. Several objectives have been identified that need to be addressed. Superpave® technology and use of the Superpave gyratory compactor (SGC) need to be incorporated into the mix design procedure. The Cantabro test for durability and resistance to stone loss needs to be adapted to SGC-prepared specimens and performance parameters established. The asphalt draindown test (AASHTO T 305-97), which was developed for stone-matrix asphalt mixtures, also needs to be evaluated for applicability to OGFC mixtures. In addition, a method for effectively evaluating air void criteria needs to be investigated. On the basis of the research conducted in this study, 50 gyrations of the SGC was selected as the design compactive effort during mix design. Also, the use of SGC-prepared samples during the Cantabro test appears to be a reasonable alternative to use of Marshall-compacted samples.
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Ijimdiya, Thomas Stephen, and Friday Elaigwu. "The Effect of Compactive Efforts on the Hydraulic Conductivity Behaviour of Oil Contaminated Lateritic Soils." Advanced Materials Research 367 (October 2011): 27–31. http://dx.doi.org/10.4028/www.scientific.net/amr.367.27.
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Large quantities of oil contaminated soils result from pipeline vandalization, onshore and offshore oil spills every year in Nigeria. An extensive laboratory program was carried out to determine the effect of varying compactive efforts on the hydraulic conductivity behaviour of oil contamination lateritic soils. Hydraulic conductivity tests were carried out on both the natural and oil contaminated soil samples at the Reduced British Standard Light (RBSL), British Standard Light (BSL), West African Standard (WAS) and British Standard Heavy (BSH) compaction energies. Contaminated specimens were prepared by mixing the lateritic soil with maximum 6 % oil concentration by weight of dry soil. The results obtained indicated a decrease in the hydraulic conductivity of the contaminated soil samples with increasing compactive efforts.
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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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Osinubi, Kolawole J. "Influence of Compactive Efforts and Compaction Delays on Lime-Treated Soil." Journal of Transportation Engineering 124, no. 2 (March 1998): 149–55. http://dx.doi.org/10.1061/(asce)0733-947x(1998)124:2(149).
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Wang, Xue Lang, and Yan Peng Zhu. "Theoretical Analysis on Compacting Effect of Lime Compaction Piles." Applied Mechanics and Materials 94-96 (September 2011): 745–49. http://dx.doi.org/10.4028/www.scientific.net/amm.94-96.745.
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According to the formers' study of theory and experiment, to analyze the mechanical properties on compacting effect of lime compaction piles. The effects of collapsible loess reinforced by the lime pile have been analyzed. The theory of collapsible loess reinforced by lime pile has made useful exploration. Through the round hole expansion theory to lime piles under expansion compacting process, the elastic-plastic solution on compacting effect of lime compaction piles has been solved. The effective radius of expansion and the law of stress change between the piles can also be determined. Finally using the finite element method to verify the proposed method, and the results show that the proposed method is effective and can provide theoretical basis and guidance for the similar projects.
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Ke, Mei Yuan, and Zhi Yu Xiao. "Die Wall Lubricated Warm Compaction of Fe-Ni-Cu-Mo-C Powders." Advanced Materials Research 168-170 (December 2010): 1016–20. http://dx.doi.org/10.4028/www.scientific.net/amr.168-170.1016.
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The combination of warm compaction and die wall lubrication, called die wall lubricated warm compaction was used to make Fe-Ni-Cu-Mo-C powder metallurgy material. Results showed that the green density could be 7.38 g•cm-3 under the pressure of 700MPa at the temperature of 120°C. The sintered density could be 7.34 g•cm-3 and dimension change was 0.19% when sintered at 1200°C for 50 minutes. Both green density and spring back effect gradually increased as the compacting pressure rose. The relation between compacting pressure and green density could be described by Huang Pei-yun double logarithm equation. Different forming conditions effecting green density in turn from big to small were compacting pressure, lubrication, compacting temperature, mixing method and compacting speed.
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Lu, Caiyun, Chunjiang Zhao, Xiu Wang, Zhijun Meng, Jian Song, Milt McGiffen, Guangwei Wu, Weiqing Fu, Jianjun Dong, and Jiayang Yu. "Effect of Postsowing Compaction on Cold and Frost Tolerance of North China Plain Winter Wheat." International Journal of Agronomy 2017 (2017): 1–9. http://dx.doi.org/10.1155/2017/1316808.
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Improper postsowing compaction negatively affects soil temperature and thereby cold and frost tolerance, particularly in extreme cold weather. In North China Plain, the temperature falls to 5 degrees below zero, even lower in winter, which is period for winter wheat growing. Thus improving temperature to promote wheat growth is important in this area. A field experiment from 2013 to 2016 was conducted to evaluate effects of postsowing compaction on soil temperature and plant population of wheat at different stages during wintering period. The effect of three postsowing compaction methods—(1) compacting wheel (CW), (2) crosskill roller (CR), and (3) V-shaped compacting roller after crosskill roller (VCRCR)—on winter soil temperatures and relation to wheat shoot growth parameters were measured. Results showed that the highest soil midwinter temperature was in the CW treatment. In the 20 cm and 40 cm soil layer, soil temperatures were ranked in the following order of CW > VCRCR > CR. Shoot numbers under CW, CR, and VCRCR treatments were statistically 12.40% and 8.18% higher under CW treatment compared to CR or VCRCR treatments at the end of wintering period. The higher soil temperature under CW treatment resulted in higher shoot number at the end of wintering period, apparently due to reduced shoot death by cold and frost damage.
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Hussain, Sadam. "Effect of Compaction Energy on Engineering Properties of Expansive Soil." Civil Engineering Journal 3, no. 8 (September 4, 2017): 610. http://dx.doi.org/10.28991/cej-030988.
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Swelling of expansive clays is one of the great hazards, a foundation engineer encounters. Each year expansive soils cause severe damage to residences, buildings, highways, pipelines, and other civil engineering structures. Strength and deformation parameters of soils are normally related to soil type and moisture. However, surprisingly limited focus has been directed to the compaction energy applied to the soil. Study presented herein is proposed to examine the effect of varying compaction energy of the engineering properties i.e. compaction characteristics, unconfined compressive strength, California bearing ratio and swell percentage of soil. When compaction energy increased from 237 KJ/m3 to 1197 KJ/m3, MDD increased from 1.61 g/cm3 to 1.75 g/cm3, OMC reduced from 31.55 percent to 21.63 percent, UCS increased from 110.8 to 230.6 KPa, and CBR increased from mere 1 percent to 10.2 percent. Results indicate substantial improvement in these properties. So, compacting soil at higher compaction energy levels can provide an effective approach for stabilization of expansive soils up to a particular limit. But if the soil is compacted more than this limit, an increase in swell potential of soil is noticed due to the reduction in permeability of soil.
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Kwunjai, Sararat, Peerapong Jitsangiam, Teewara Suwan, Damrongsak Rinchumphu, Hemwadee Thongchua, Prinya Chindaprasirt, and Sate Sampattagul. "Crushed Rock Geopolymer as a Future Road Construction Material: An Evaluation on Strength Performance and Compaction Characteristics." Key Engineering Materials 841 (May 2020): 171–76. http://dx.doi.org/10.4028/www.scientific.net/kem.841.171.
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To be more sustainable in the road construction industry, the rock-based geopolymer concept should be applied with an aim to create a geopolymer-based road structural layer. The research program studied on the geopolymer for road construction was newly established at Chiang Mai University, Thailand. This study concentrated in a preliminarily evaluation of strength performance and compaction characteristics of crushed rock-based geopolymer (CR-GP) to partially or totally replace the usage of ordinary Portland cement (OPC) as a road stabilizing agent. The standard crushed rock (CR), complying with the standard of road base materials, was obtained from a real construction field. The experiment on CR gradation, compaction and compressive strength were carried out. The results showed that CR of a finer grading curve with higher surface areas tended to better react with alkaline activators, resulting in relatively high compressive strength. The mechanical modification with compaction is one of the simplest methods for strength improvement. It found that higher compactive efforts (the modified compaction), higher densification than that of the standard compaction, corresponding to the compaction theory of soil mechanics. CR-GP having an ideal (reconstituted) grading curve achieved higher compressive strength than that of the standard grading one of a well-graded pattern. Overall, it could be concluded CR-GP has intrinsic compaction characteristics of which at its optimum point of compaction, CR-GP could address the minimum requirement for road standard in terms of compressive strength, by which it could be used as an alternative material in replacing the consumption of OPC.
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Li, Fu Rong, Hou Chao Sun, and Zhao Yu Wang. "Mechanism Analysis and Experimental Study of Soil-Compacting by Silent Piling." Applied Mechanics and Materials 170-173 (May 2012): 457–60. http://dx.doi.org/10.4028/www.scientific.net/amm.170-173.457.
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The mechanism of soil-compacting effect by silent piling is analyzed, and based on large-scale model box test, using soft clay of typical sites in Yancheng District, taking the single pile as the study objects respectively, and studying the soil compaction effects with the process of sinking into the single pile, analyzing the variation law of the soil deformation and pore water pressure while sinking into the single pile. The results shows that the greater the radial distance, the smaller of soil compaction effect, the influence scope of soil compaction effects on the displacement and pore water pressure reaches 0.6 times and 0.5 times the pile length sinking the single pile, which is accord to the actual engineering. The results could guide the pile foundation construction on soft soil.
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Suzuki, Hiroyuki Y., and Hidenori Kuroki. "Development of High-Speed Centrifugal Compaction Process of Alumina." Advances in Science and Technology 45 (October 2006): 421–26. http://dx.doi.org/10.4028/www.scientific.net/ast.45.421.
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High-Speed Centrifugal Compaction Process (HCP) is one of slip-using compacting method in which the compacts are obtained as sediments under huge centrifugal force. Compacting mechanism of the HCP differs from other slip using compacting methods. The unique compacting mechanism of the HCP leads a number of characteristics such as a higher compacting speed, wide applicability for net shape formation, etc. Moreover, the most outstanding characteristics of the HCP can be found in homogeneous and flawless microstructure of the green compacts, because the process possesses an intrinsic defect removing function. That is, the defect inducing matters in slips (powder aggregates, inclusions, bubbles) are removed from the main part of the compact by the classification effect of centrifuge, and therefore the HCP alumina exhibits superior sinterabiliy and higher strength and hardness than most other aluminas. Many of the advantageous characteristics of the HCP can be improved with a higher centrifugal force.
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Libasse, Sow. "Study of the Behaviour of Senegalese Ballast Materials during Compaction with the C-Mould: Case of Bandia Limestone and Diack Basalt." Key Engineering Materials 831 (February 2020): 81–86. http://dx.doi.org/10.4028/www.scientific.net/kem.831.81.
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Work presented in this article focuses on the study of the behaviour of materials from Senegalese quarries during compaction. These are Bandia Limestone (Sindia, Thiès Region) and Diack Basalt (Ngoundiane, Thiès Region). The grain size studied is 25/50 mm as for any material studied for use as railway ballast. The Proctor C-Mould for compacting large diameter materials was made for the occasion. With γdmax = 2.142 g/cm3 and WOPM = 5.3%, the compaction results clearly show the poor behaviour of the limestone under the effect of repeated loads and water. It shows a reduction in fine elements of the aggregates of initial diameter 25/50, as well as a significant cohesion under the effect of water with the formation of a muddy paste. The compaction references that characterize Diack Basalt are: γdmax = 2.15 g/cm3 and WOPM = 0.37%. Diack Basalt's compaction behaviour shows good performance. It does not break down into fine particles and the settling observed during compaction is similar to just tightening the grains and then stabilizing the material.
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Jobbágy, J., P. Findura, and F. Janík. "Effect of irrigation machines on soil compaction." Research in Agricultural Engineering 60, Special Issue (December 30, 2014): S1—S8. http://dx.doi.org/10.17221/26/2013-rae.
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The analysis of soil compaction with chassis of a wide-span irrigation machine Valmont was determined. The sprinkler had 12 two-wheeled chassis (size of tyre 14.9'' × 24''). During the evaluation of soil compaction, we monitored the values of penetration resistance and soil moisture during the operation of the sprinkler. Considering the performance parameters of the pump, the sprinkler was only half of its length (300 m) in the technological operation. In this area, also field measurements were performed in 19 monitoring points spaced both in tracks and outside the chassis tracks. The analysis showed the impact of compression with sprinkler wheels. The correction of obtained results of penetration resistance was applied in connection with soil moisture (mass) values according to Act No. 220/2004 (Lhotský et al. 1985). The results of average resistance ranged from 1.2 to 3.26 MPa. The values of the max. resistance ranged from 2.3 to 5.35 MPa. The results indicated a shallow soil compaction; however, it is not devastating.
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Canbaz, Mehmet, and Erman Acay. "Effect of high temperature on SCC containing fly ash." Challenge Journal of Concrete Research Letters 12, no. 1 (March 12, 2021): 1. http://dx.doi.org/10.20528/cjcrl.2021.01.001.
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The effect of high temperature on self-compacting concrete, which contains different amounts of fly ash, has been investigated. By considering the effect of concrete age and increased temperatures, the optimum fly ash-cement ratio for the optimum concrete strength is determined using experimental studies. Self-compacting concrete specimens are produced, with fly ash/cement ratios of 0%, 20% and 40%. Specimens were cured for 28, 56 and 90 days. After curing was completed, the specimens were subjected to temperatures of 20°C, 100°C, 400°C, 700°C and 900°C for three hours. After the cooling process, tests were performed to determine the unit weight, ultrasonic pulse velocity and compressive strength of the specimens. According to the experiment results, an increase in fly ash ratio causes a decrease in the compressive strength of self-compacting concrete. However, it positively contributes to self-compaction and strength loss at high temperatures. The utilization of fly ash in concrete significantly contributes to the environment and the economy. For this reason, the addition of 20% fly ash to concrete is considered to be effective.
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Wróbel, Marek, Marcin Jewiarz, Krzysztof Mudryk, and Adrian Knapczyk. "Influence of Raw Material Drying Temperature on the Scots Pine (Pinus sylvestris L.) Biomass Agglomeration Process—A Preliminary Study." Energies 13, no. 7 (April 9, 2020): 1809. http://dx.doi.org/10.3390/en13071809.
Full textAbstract:
For biomass compaction, it is important to determine all aspects of the process that will affect the quality of pellets and briquettes. The low bulk density of biomass leads to many problems in transportation and storage, necessitating the use of a compaction process to ensure a solid density of at least 1000 kg·m−3 and bulk density of at least 600 kg·m−3. These parameters should be achieved at a relatively low compaction pressure that can be achieved through the proper preparation of the raw material. As the compaction process includes a drying stage, the aim of this work is to determine the influence of the drying temperature of pine biomass in the range of 60–140 °C on the compaction process. To determine whether this effect is compensated by the moisture, compaction was carried out on the material in a dry state and on the materials with moisture contents of 5% and 10% and for compacting pressures in the 130.8–457.8 MPa range. It was shown that drying temperature affects the specific density and mechanical durability of the pellets obtained from the raw material in the dry state, while an increase in the moisture content of the raw material neutralizes this effect.
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Prayuda, Hakas, Berkat Cipta Zega, Fanny Monika, Fadillawaty Saleh, and Martyana Dwi Cahyati. "FRESH AND MECHANICAL CHARACTERISTICS OF SELF-COMPACTING POLYPROPYLENE FIBER CONCRETE INCORPORATED WITH KAOLIN." SINERGI 24, no. 3 (July 9, 2020): 223. http://dx.doi.org/10.22441/sinergi.2020.3.007.
Full textAbstract:
Self Compacting Concrete (SCC) is concrete with high fluidity so that it can flow and fill the spaces in the mold without the compaction process. This study discusses the effect of the adding of kaolin and polypropylene fibers in order to increase the flowability, compressive strength, flexural strength, and tensile strength in self-compacting concrete. The additional material of kaolin was 5%, 10%, and 15% of the cement weight. The polypropylene fibers were 1%, 1.5%, and 2%. The flowability test, which was used, was Table flow, V-Funnel, and L-Box. Compressive strength testing was conducted when the concrete was 7, 14, and 28 days old. The flexural test was performed with a measurement of 150 x 150 x 600 mm as many as 18 specimens tested at the age of 28 days. The results showed that the addition of kaolin and polypropylene fibers met the flowability specifications of self-compacting concrete. The addition of polypropylene can increase the flexural strength and tensile strength of the concrete beam, but cannot increase the compressive strength of self-compacting concrete.