Experimental and Numerical Study of Bearing Capacity and Effect of Specimen Size on Uniform Sand with Medium Density, Reinforced with Nonwoven Geotextile

Abstract

Reinforced soil is a composite material in which elements of high tensile resistance are implemented to increase the tensile resistance of the soil. Geotextiles are one of the major groups of geosynthetic products that are used for soil reinforcement. This paper deals with the effects of using nonwoven geotextile to improve the ultimate bearing capacity of footings resting on sand with medium density. The plate load tests were performed using 27 cm × 27 cm and 35 cm × 35 cm square plates, and the effects of the depth of the first layer of geotextile, vertical spacing as well as the number of geotextile layers on the ultimate bearing capacity of the footings were studied. Moreover, the impact of plate size and sample size was examined numerically by performing 3-D finite element analyses with different sizes of the square plate. The experimental results showed that the maximum bearing capacity is achieved for the system with four geotextile layers, vertical spacing of 0.3B between geotextile layers and geotextile width of 4B, where B is the width of the plate. The numerical analyses indicated that with increasing the size of the plate up to 65 cm, the values of the bearing capacity ratio (BCR) gradually decrease; however, additional increase in the size of the plate has a little impact on BCR values.