An experimental evaluation of size effect and bearing capacity of footing on non-woven geotextile-reinforced sand

Abstract

Reinforced soil is a composite material in which elements with tensile strength were utilized for reinforcement. Geotextile is the most common material in group of geosynthetics for soil reinforcement. This paper presents the effect of a non-woven geotextile which have a higher failure strain on bearing capacity of rigid footing constructed on sand. A research has been done to investigate the bearing capacity of granular soil with plates which have standard width according to ASTM D 1194. In this study, a total number of 62 model tests were carried out in a laboratory using two square rigid steel plate with the sides of 270 mm and 350 mm. A broad series of conditions was tested by varying parameters such as the location of upper layer of geotextile, number of geotextile layers, width of reinforcement and vertical spacing between layers. In second step a series of tests were additionally carried out by varying of spaces between layers and width of geotextile layers in proportion to increase of depth. The results demonstrated that in all cases non-woven geotextile increases bearing capacity and the maximum bearing capacity was obtained in 4-layer reinforcement system. It is also shown that the optimum value of vertical spaces between layers after the upper one are respectively, 0.30 B, 0.35 B, 0.45 B. In addition, the results indicate that optimum width of the first two layers of reinforcement are 4 B and for the third and fourth one are 3 B and 2.5 B respectively.