BEHAVIOUR OF GEOSYNTHETIC REINFORCED SOIL OVERLYING LOOSE SAND

Document Type : Scientific and technological

Author

Teaching Assistant, Faculty of Engineering, Cairo University, Egypt.

Abstract

This paper presents the results of experimental model tests to investigate the performance of geogrid as reinforcement element using strip footing model resting on geogrid reinforced replacement granular 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 enhancement of ultimate bearing capacity of reinforced replacement soil, investigate the behavior of the generated strains at geogrid for different configuration of reinforced replacement soil, and to assess available methods for calculating the improved bearing capacity. The generated strains increase instantaneously by increasing the applied footing pressure. However, the rate of increasing the strains is low at lower settlement due to geogrid slack, and the rate increased at moderate settlement. The developed strains decreased gradually beyond the footing width due to occurrence pullout for reinforcement layers. Available analytical methods for calculating the improved bearing capacity are compared.

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