Study On Strength Characteristics And Foundation Bearing Capacity Of Reticulated Red Clay In North Jiangxi

In engineering practice,it was found that the strength characteristics of reticulated red clay are distinct from ordinary red clay or old clay.Because of the lack of systematic research on reticulated red clay,the selection of strength parameters is conservative in engineering design,which has caused great waste to economy and environment.Therefore,it is necessary to carry out in-depth research on mineral composition,microstructure,strength characteristics and foundation bearing capacity of reticulated red clay in North Jiangxi,so as to have a better understanding and design application of foundation bearing capacity design.This paper studies the reticulated red clay in North Jiangxi as the research object,through field investigation,indoor and field test,theoretical analysis and numerical calculation.First of all,the reticulated red clay of northern Jiangxi area divided into homogeneous and heterogeneous through field investigation;X diffraction and scanning electron microscopy showed that the mineral composition of reticulated red clay was mainly composed of quartz and muscovite.The microscopic characteristics of white clay are flaky and overlapping,small and connected pores,the red clay is tightly connected,the pore distribution is scattered and disconnected.Through direct shear test and three axis test,the relationship between the shear strength of the reticulated red clay with the change of water content has been established,and found that the three axial compression failure form of the original reticulated red clay is changed from brittleness to pressure hardening with the increase of water content.By analyzing the results of 11 groups of static load tests,two settlement calculation methods of exponential model and Et-beta relation model are proposed.The project data of 27 reticulated laterite strata are statistically analyzed,get a range of the characteristic value of the reticulated red clay bearing capacity is 377.20 kPa ~ 417.51 kPa and the deformation control parameter s/b is0.0045 ~ 0.007 with 95% guarantee rate.Finally,according to the analysis results of finite element software,it is suggested that the static load test needs to control the spacing of the loading platform with more than 6 times the diameter of the plate and the size of the press plate should be controlled between 0.6 and 1.1m on the reticulated red clay layer.