关键词: 加筋土;三轴试验;大变形;残余强度;

Abstract: In order to study the deformation and bearing characteristics of reinforced sand under large deformation, a triaxial test of reinforced gravel sand was carried out, in which the geogrid was used as the reinforcing material and the maximum shear strain reached 25%.The stress-strain characteristic and volume strain of reinforced gravel sand samples with different reinforced forms and reinforced layers were compared and analyzed.The test results show that the reinforcement can significantly improve the peak strength and residual strength of the specimens and it has a higher enhancing effect on the residual strength than the peak strength.Ring combination reinforcement has the most obvious enhancing effect, that its enhancing effects on the peak deviation stress, initial residual strength and ultimate residual strength were 77.1%,117.0% and 200.5%,respectively.The reinforcement tendon can restrain the volume deformation of gravel sand samples, especially the ring reinforcement has the strongest restraint ability to the volume deformation of gravel sand samples, and it can also effectively restrain the increasing trend of sand dilatation rate under large deformation

Key words: reinforced soil; triaxial test; larger deformation; residual strength