非饱和路基土模量确定方法

基于孔隙比和含水量随净应力和基质吸力变化的特征，建立孔隙比和含水量与净应力和基质吸力之间的关系式，并结合非饱和土的本构关系，得到弹性模量E和H及体积模量 和 与净应力、基质吸力和含水量之间的关系。然后采用试验数据拟合孔隙比–净应力–基质吸力三维曲面及体积含水量–净应力–基质吸力三维曲面，得到弹性模量E和H及体积模量 和 与净应力和含水量关系式中的参数，并分析了净应力和含水量对这4个模量的影响的规律性。分析结果表明：在一定净应力下，模量E随着质量含水量增大而减小；净应力越大，模量E随质量含水量减小越显著；在同一质量含水量下，净应力越大，模量E越大。随着质量含水量增大，模量H单调减小；随着净应力增大，模量H单调增大。在低质量含水量时，增加净应力，体积含水量增大，当质量含水量增加到一定程度以后，增加净应力会引起体积含水量的减小。在一定净应力下，增加吸力会使体积含水量减小；在同一质量含水量下，增加净应力能够减弱吸力对体积含水量的影响。

DETERMINATION METHOD OF MODULUS OF UNSATURATED SUBGRADE SOIL

Based on the basic variation characteristics of void ratio and water content with net stress and matric suction,the relationships of void ratio and water content with net stress and matric suction are established.Combined with constitutive relation of unsaturated soil,elastic moduli and,and volumetric moduli and in the form of net stress and matric suction,as well as water content are obtained.Then void ratio-net stress-matric suction 3D surface and volumetric water content-net stress-matric suction 3D surface are fitted with experiment data;and the parameters in the relationships of elastic moduli and,and volumetric moduli and with net stress and water content are obtained.The influences of net stress and water content on the four moduli are analyzed.The analysis results are as follows:Under a certain net stress,modulus E decreases with the increase of mass water content;the larger the net stress,the more significant the decrease of modulus E with the increase of mass water content;under a certain mass water content,the larger the net stress,the larger the modulus E.Modulus H decreases monotonously with the increase of mass water content and increases monotonously with the increase of net stress.With the increase of net stress,volumetric water content increases at low mass water content and decreases after the mass water content increases to a certain degree.Under a certain net stress,volumetric water content decreases with the increase of suction;under a certain mass water content,the influence of suction on volumetric water content is weakened by increasing net stress.