渗透系数极端情况下饱和土中压缩波波速及其物理本质  

Compressional wave velocity and its physical nature in saturated soils with extreme permeability values

作　　者：李鹏[1] 宋二祥[1] 

机构地区：[1]清华大学土木工程系,北京100084

出　　处：《岩土力学》2012年第7期1979-1985,共7页Rock and Soil Mechanics

基　　金：国家自然科学基金委员会重点资助项目(No.51038007)

摘　　要：目前对渗透系数取极端值情况下饱和土中两类压缩波物理本质的理解尚不够清晰,比如文献中对渗透系数无穷大情况下饱和土中两类压缩波波速的求解有不同的结果。结合Zienkiewicz给出的土动力学基本方程,深入讨论了流体运动方程的建立,推导了饱和土一维压缩弹性问题的动力控制方程及其u-w、u-W形式,进而得出渗透系数取0和取无穷大这两种极端情况下饱和土中压缩波的波速,解释了其物理意义。提出了惯性耦合力的概念,指出两相体动力分析时土骨架和孔隙水之间的相互作用包含渗透力和惯性耦合力两项,并重点讨论了衡量惯性耦合力的参数孔隙度对压缩波波速的影响。At present time the understanding of the physical nature of two kinds of compressional waves in saturated soils with extreme permeability is still not clear.For example the velocities of two compressional waves in case of infinite permeability given in different literatures are inconsistent.By using the dynamic basic formulations of saturated soils given by Zienkiewicz,the establishment of pore water motion equation is discussed.Then one-dimensional compression controlling equations and wave equations in u-w and u-W forms are derived,from which the compressional wave velocities in extreme cases of zero and infinite permeability are obtained;and their physical natures are also explained.The conception of inertial-coupling force is put forward;and it is emphasized that in dynamic analysis of saturated soils the interaction between soil skeleton and pore water consists of two parts： seepage force and inertial-coupling force.The parameter of measuring inertial-coupling-force is porosity;and its influence on compressional wave velocities is discussed.

关 键 词：饱和土 动力分析 两类压缩波 波速 惯性耦合力 孔隙度 

分 类 号：TU435[建筑科学—岩土工程]