Experimental study on deformation characteristics of collapsible loess under isotropic stress

In order to study the deformation characteristics of collapsible loess and to construct different vertical stresses, different isotropic stresses are used to represent the vertical stresses, and their corresponding stresses are set to be the hidden stresses in different positions of collapsible loess foundation are analyzed by using 0, 50, 100, 220, 330 and 400 kPa. In this study, various kinds of deformation analysis of collapsible loess are needed. Ground settlement tester, GJY K-0 tester produced by Suzhou Longstan Automation Factory and ADINA software are used. Experiments show that different isotropic stresses are applied to the foundation, and the hidden stresses of the loess are gradually decreasing under the action of different filling heights. At the same time, the higher the height of the fill, the faster the decline of the underlying stress of the foundation loess. With the increase of time at the bottom of the cushion, the corresponding underlying stress at the midline decreases, while with the increase of the height of the fill, the corresponding underlying stress at the midline rises. Study of the underlying stress at the bottom of the pile is set up differently. Under certain time and position of the pile bottom, increasing the isotropic stress can increase the hidden stress at the corresponding pile bottom, and change the filling height at the pile bottom has little effect on the hidden stress at the pile bottom. Under the combined action of water content and isotropic stress, they are positively correlated with the change of lateral stress. With the increase of isotropic stress, the K-0 coefficient rises as a whole. This study can provide a strong reference for the deformation characteristics of collapsible loess itself, and help construction workers to improve the safety of the project in the field of engineering construction.