Bearing Capacity Evaluation of Square Footing Resting on Reinforced Sand

An experimental study is carried out to improve the bearing capacity of soils by using geotextile. In the present study geotextile (tire reinforcement) is used as geotextile, whereas sand is used as a soil medium. This research work presents the results of laboratory load tests on model square footings supported on reinforced sand beds. A total of twenty-seven load tests are conducted to evaluate the effects of single layer reinforcement placed below square model footings. The parameters of the testing program of the research work are the depth of reinforcement, the plan area of reinforcement, and the number of reinforcements. From the experimental data, it is indicated that there is an optimum reinforcement depth at which the bearing capacity is the highest. Also, the optimum size of reinforcement is found to be ۱.۵ B×۱.۵ B irrespective of the type of reinforcing materials used. The bearing capacity of reinforced sand is also found to increase with the number of reinforcement layer and reinforcement size when the reinforcement is placed within a certain effective zone with high relative density. The optimum placement position of geotextile is found to be ۰.۵B to ۰.۷۵B from the base of the footing .The tests are done at two different relative densities, i.e., ۴۰% and ۶۰%. The bulk unit weight of sandy soil is ۱۴.۸۱ KN/m³. Maximum gain in load carrying capacity is obtained when depth of reinforcement/width of footing (Dr/B) is ۰.۵ at relative density of ۴۰% and ۰.۷۵ at a relative density of ۶۰%.In addition, the data indicate that increasing reinforcement beyond a certain value would not bring about further increase in the bearing capacity of the soil.

Keywords:

bearing capacity , load settlement behavior , rubber tire wastes , sandy soil , square footing