Collapsible Loess Increase (decrease) In Wet Deformation Behavior Of Experimental Research

This paper is an important part of the scientific project <> (authorized number:598780401). Based on the analysis of literatures about collapsing deformation of loess soil, aimed at the actuality of past research on collapsible loess that emphasized particularly on collapsing deformation after adequately inundated and saturated, but paid little attention to the research on the moistening (drying) deformation when dampened (dried) to some humidity, and in the past, the bilinear method was mainly used instead of the single-track method, this paper uses both single-track method and bilinear method to carry out monaxial compression test and triaxial shear test on undisturbed loess( Q3) comes from Longxi area in Gansu province.Through contrasting and analysing the experimental results from these methods, the paper summarizes the regularity of collapsing deformation and the shear strength index changes with the degree of saturation and stress, describes the collapsing deformation properties and strength characters of the collapsible loess in the course of moistening and drying, and describes the influence to collapsing deformation of loess from different paths of stress. Through performing monaxial compression test on samples with different paths of inundation and direction of press, proves the conclusion that collapse has nothing to do with the path of inundation and the collapsible loess has the prominent anisotropy characters.Finally ,the author establishes the moistening and drying constitutive model of collapsible loess, which provides basis for future engineering design and numerical calculation.