Determination of calculation parameters of bearing capacity of super-soft soil composite foundation reinforced by bamboo grid and sand cushion

Abstract

When the hydraulic fill soft soil foundation is deep soft soil foundation and the surface layer is super-soft soil, the reinforcement of sludge or super-soft soil foundation surface with bamboo grid can meet the requirements of personnel and construction equipment. The existing calculation parameters of bearing capacity of super-soft soil foundations reinforced by bamboo grid and sand cushion mainly rely on experience. In this paper, the load settlement and load strain laws are obtained through indoor model tests, and then the angle between the tension of bamboo grid and the horizontal plane and the stress diffusion angle of bamboo grid and sand cushion can be determined. The test results show: (1) when s/b is equal to 0.10 and 0.15, the angles between the bamboo grid tension and the horizontal plane are 6.74° and 7.93° respectively, which are far less than 20° by Yamanouchi; (2) The stress diffusion angle of bamboo grid and sand cushion is related to the settlement ratio and thickness width ratio. When the settlement ratio is certain, the stress diffusion angle increases with the increase of thickness to width ratio, and the spacing of bamboo grids also has an effect on the stress diffusion angle; when the thickness-to-width ratio is 0.39, 0.58 and 0.78, the mean value of the stress diffusion angle is respectively 14.2°, 2 6.5°, and 31°, and the maximum value of this test reaches 38.74°.