STRUCTURAL QUANTITATIVE PARAMETER OF INTACT LOESS WITH DIFFERENT WATER CONTENTS UNDER TRIAXIAL STRESS CONDITION

The existing state of structural studies is discussed.Load is applied on disturbed saturated loess samples with the same dry density in order to destroy the structure of intact loess.Based on the stress-strain curves obtained by triaxial compression tests of intact loess and disturbed saturated loess,the quantitative comprehensive structural parameter is used,which can reflect not only the arrangement but also the coherent structure of soil particles.The effects of water content and confining pressure on the structural parameter are investigated during the shear course. The study indicates that (1) structural parameter can not only reveal the influences of water content and confining pressure on the structure of the intact loess under shear,but also is of rationality,sensitivity and stability;(2) structural parameter decreases with the increase of water content,and this change tendency decreases with the increase of strain;and (3) when initial loading is applied and failure of sample occurs,structural parameter decreases with increase of confining pressure,and when strain reaches 15%,structural parameter firstly increases and then decreases with the increase of confining pressure.