Moistening Deformation Properties Of Compacted Loess And Calculation Of Subsoil Moistening Derormation

From the aspect of study object, The past research on the characteristics of loess deformation, focused predominantly on undisturbed loess, but paid less attention to compacted loess; from the aspect of study contents, the past research on the characteristics of loess deformation emphasized particularly on collapsing deformation after adequately inundated and saturated, but paid little attention to the research on the moistening deformation when dampened to some humidity.Though the undisturbed loess is the large geology environment which engineering in areas of loess is depended on, loess is compacted for the most part when used as a material for building, therefore engineering characteristics of compacted loess have closer relation to engineering construction. Studies concerning the influence on deformation and strength when the variation of stress state, stress history, stress level and stress path are aimed at the undisturbed loess in traditional loess mechanics, whether the conclusions obtained from which are applicable to compacted or not is unknown; in engineering practice, the main threat to loess subsoil is not from entire collapsing or most parts'collapsing caused by the fully dampened of uniform soil-layer, but from the great collapsing discrepancy caused by different moistening level along the soil-layer, which leads to damage of buildings based on loess subsoil. For these reasons, studying the moistening and drying deformation characteristics of compacted loess has direct practical significance for guiding engineering construction.Through confined compression, this paper studies the moistening characteristics of compacted loess with different compacted degree, and summarizes the regularity of deformation characteristics of compacted loess with the degree of dry density and moisture content, and the regularity of compressive deformation and collapsing deformation including their inter-transformation in the course of moistening is also described, besides the influence of the loading path, dampening path and the coupling of them to the deformation of compacted loess is obtained; on the basis of double-1ine method collapsing test, the concept of coefficient of moistening collapsibility is put forward, and on the strength of compressible-modulus method to calculate the subsoil's subsidence, modulus of compressibility is revised, as can reflect the developing degree and nonlinear property of the...