Abstract
The present investigation proposes a new type of reinforcing material in the form of three-dimensional geogrid. The performance of a model square footing resting on the three-dimensional geogrid reinforced sand bed is investigated by conducting laboratory scaled plate load tests. Two types of 3D geogrids with triangular and rectangular pattern were used. The improvement in bearing capacity and surface deformation were evaluated and the effect of depth of placement of the first layer of reinforcement, the spacing between layers and number of layers were investigated. The results obtained were compared with the results of unreinforced sand bed and conventional geogrid reinforced sand bed. The bearing capacity of the footing was improved by 1.85 times by the provision of a single layer of conventional reinforcement, whereas, 2.7 and 3.1 times improvement was observed with 3D geogrids of the triangular and rectangular pattern at an optimum depth of 0.25B. The results show that the spacing between two consecutive layers varies with the type of reinforcement. Two layers of 3D geogrid (rectangular) at an optimum spacing of 0.75B completely eliminate the surface heave of soil surrounding the footing. In the case of conventional geogrid and 3D geogrid with triangular pattern, the optimum number of reinforcement layer was obtained as four. Three layers of 3D geogrid with rectangular pattern placed at an optimum spacing of 0.75B give a BCR value of 6.4. Also, 3D geogrids perform better than conventional geogrids in reducing surface deformation.
References
Abu-Farsakh M, Qiming Chen, Radhey Sharma (2013) An experimental evaluation of the behavior of footings on geosynthetic reinforced sand. Soils Found 53(2):335–348
Adams MT, Collin JG (1997) Large model spread footing load tests on geosynthetic reinforced soil foundations. J Geotech Geoenviron Eng 123(1):66–72
Alawaji H A (2001) Settlement and bearing capacity of geogrid reinforced sand over collapsible soil. Geotext Geomembr 19:75–88
Biswas A, S M Krishna, Dash S K (2016) Behavior of geosynthetic reinforced soil foundation systems supported on stiff clay subgrade. Int J Geomech. doi:10.1061/(ASCE)GM.1943-5622.0000559
Boushehrian JH, Hataf N (2003) Experimental and numerical investigation of the bearing capacity of model circular and ring footings on reinforced sand. Geotext Geomembr 21(4):241–256
Chaudhary A K, Jha J N, Gill K S (2010) Laboratory investigation of bearing capacity behaviour of strip footing on reinforced flyash slope. Geotext Geomembr 28:393–402
Das BM, Omar MT (1994) The effects of foundation width on model tests for the bearing capacity of sand with geogrid reinforcement. Geotech Geol Eng 12(2):133–141
Ghosh A, Bera A K (2005) Bearing capacity of square footing on pond ash reinforced with jute-geotextile. Geotext Geomembr 23(2):144–173
Khing K H, Das B M, Puff V K, et. al. (1993) The bearing-capacity of a strip foundation on geogrid-reinforced sand. Geotext Geomembr 12:351–361
Latha G M, Somwanshi A (2009) Bearing capacity of square footings on geosynthetic reinforced sand. Geotext Geomembr 27(4):281–294
Mandal J N, Shah H S (1992) Bearing capacity tests on geogrid-reinforced clay. Geotext Geomembr 11(3):327–333
Omar MT, Das BM, Puri VK, Yen SC (1993) Ultimate bearing capacity of shallow foundations on sand with geogrid reinforcement. Can Geotech J 30(3):545–549
Sharma R, ChenQ, Abu-Farsakh M, Yoon S (2009) Analytical modeling of geogrid reinforced soil foundation. Geotext Geomembr 27(1):63–72
Tafreshi, S. N. M, Dawson A R. (2010) Behaviour of footings on reinforced sand subjected to repeated loading—comparing use of 3D and planar geotextile. Geotext Geomembr 28(5): 434–447
Vinod P, Ajitha B Bhaskar, Sreehari S (2009) Behavior of a model square footing on loose sand reinforced with braided coir rope. Geotext Geomembr 27:464–474
Yetimoglu T, Wu, J TH, Saglamer A (1994) Bearing capacity of rectangular footings on geogrid-reinforced sand. J Geotech Eng 120(12):2083–2099
Yoo C (2001) Laboratory investigation of bearing capacity behavior of strip footing on geogrid-reinforced sand slope. Geotext Geomembr 19:279–298
Lawton EC, Khire MV, Fox NS (1993) Reinforcement of soils by malt oriented geosynthetic inclusions. J Geotechnical Eng. 119(2)
Harikumar M, Sankar N, Chandrakaran S (2016) Behaviour of model footing resting on sand bed reinforced with multi-directional reinforcing elements. Geotext Geomembr 44:568–578
Khedkar M S, Mandal J N (2009) Pullout behavior of cellular reinforcements. Geotext Geomembr 27:262–271
Lin Y L, Li X X, Zhang M X (2014) Effect of reinforcement form on the pullout behavior of reinforced sand. Ground Improvement and Geosynthetics GSP 238© ASCE 2014, pp 380–388
Zhang M X, Javadi A A, Min X (2006) Triaxial test of sand reinforced with 3D inclusions. Geotext Geomembr 27:201–209
Mosallanezhad M, Alfaro M C, Hataf N, Sadat Taghavi S H (2016) Performance of the new reinforcement system in the increase of shear strength of typical geogrid interface with soil. Geotext Geomembr 44(3):457–462
Dash SK, Krishnaswamy NR, Rajagopal K (2001) Bearing capacity of strip footings supported on geocell-reinforced sand. Geotext Geomembr 19(4):235–256
Dash S K, Rajagopal K, Krishnaswamy N R (2001) Strip footings on gepcell reinforced sand beds with additional planar reinforcement. Geotext Geomembr 19:529–538
Dash S K, Sireesh S, Sitharam, T G (2003) Model studies on circular footing supported on geocell reinforced sand underlain by soft clay. Geotext Geomembr 21(4):197–219.
Latha G M, Somvanshi A (2009) Effect of reinforcement form on the bearing capacity of square footings on sand. Geotext Geomembr 27:409–422
Sireesh S, Seetharam T G, Dash S K (2009) Bearing capacity of circular footing on geocell-sand mattress overlying clay bed with void. Geotext Geomembr 27:89–98
Dash SK (2012) Effect of geocell type on load carrying mechanism of geocell-reinforced sand foundations. Int J Geomech 12(5):537–548
Hegde A, Sitharam TG (2013) Experimental and numerical studies on footings supported on geocell reinforced sand and clay beds. Int J Geotech Eng 7(4):346–354
Hegde A, Sitharam TG (2015) Experimental and analytical studies on soft clay beds reinforced with bamboo cells and geocells. Int J Geosynth Ground Eng 1(2):1–13
IS:1888 (1982) Method of load test on Soils, Bureau of Indian Standards, New Delhi, India
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Makkar, F.M., Chandrakaran, S. & Sankar, N. Behaviour of Model Square Footing Resting on Sand Reinforced with Three-Dimensional Geogrid. Int. J. of Geosynth. and Ground Eng. 3, 3 (2017). https://doi.org/10.1007/s40891-016-0083-1
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DOI: https://doi.org/10.1007/s40891-016-0083-1