EXPERIMENTAL TESTS ON STRIP FOOTINGS RESTING ON GEOSYNTHETIC REINFORCED REPLACEMENT SOIL OVERLYING LOOSE SAND

Hussein, Mohamed Kamal

EXPERIMENTAL TESTS ON STRIP FOOTINGS RESTING ON GEOSYNTHETIC REINFORCED REPLACEMENT SOIL OVERLYING LOOSE SAND

Document Type : Scientific and technological

Author

Mohamed kamal Hussein

Teaching Assistant, Faculty of Engineering, Cairo University,

Abstract

This paper presents the results of laboratory model tests to investigate the performance of shallow footings resting on geosynthetic reinforced replacement soil overlying loose sand. The model tests are conducted in a 1250 mm long, 400 mm wide, and 800 mm deep steel tank. A strip footing is simulated using a 30 mm thick, 100 mm wide, and 380 mm long steel plate. The purpose of the testing program is to determine the effect of the configuration of reinforced replacement soil on improvement in bearing capacity and settlement of the strip footing. The number of reinforcement layers (N = 1, 2, 3), length of reinforcement (L = 6B, 4B, 2B), and thickness of the replacement soil relative to footing width (d/B = 1.2, 1.5, 1.8) are varied. A punching shear failure mechanism is observed in the laboratory tests for unreinforced soil, which tends to fade as the number of reinforcement layers increase. Improvements in observed settlement occurred at settlements beyond 10% of the footing width. Increase in bearing capacity ratios due to increasing the number of reinforcement layers, length of reinforcement, and thickness of replacement soil is discussed.

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