Deformation mechanism and soil evolution analysis based on different types geogrid reinforced foundation

Abstract

Geogrids are extensively used to improve the bearing capacity of low strength soil and reduce the settlement of soft soil foundations. This study aims to compare the bearing capacity and deformation characteristics of geogrid reinforced foundation with different types of geogrids (uniaxial, biaxial, triaxial) and different reinforcement layers (N = 1, 2, 3) in reduced-scale transparent soil model tests. The images of the foundation model are captured by the laser transmitter and digital camera. These images are further analyzed to study the foundation deformation of different cases by digital image processing technique. The results show that triaxial geogrid reinforced foundation has a better bearing capacity than the uniaxial geogrid and biaxial geogrid reinforced foundation. In the process of foundation settlement, the slip crack surface and ground heave gradually develop with the bottom-up diffusion of horizontal and vertical displacements of the soil. Local shear failure first occurred in the bottom of the foundation, and then transformed into general shear failure. These results visualize and quantify the soil displacement transfer and spreading behavior in geogrid reinforced foundations. This paper illustrates the effects that geogrid reinforcing at a microscopic scale under strip footing loads.