Biot 理论与修正的 Biot 理论比较及讨论
2016-01-18刘志军,夏唐代,黄睿等
第一作者 刘志军 男,博士生,1988年生
Biot理论与修正的Biot理论比较及讨论
刘志军1,2,夏唐代1,2,黄睿1,2,陈炜昀3
(1. 浙江大学 软弱土与环境土工教育部重点实验室,杭州310058;2.浙江大学 滨海和城市岩土工程研究中心,杭州310058; 3. 南京工业大学 交通学院,南京210009)
摘要:对Biot理论和修正的Biot理论中的波动方程进行了详细推导,注明了每个参数的量纲和准确含义,并基于修正的Biot理论导出了三种不同形式的波动方程;对两种理论进行比较,得到了Biot弹性系数表达式,并分析了两者的应力及其对应关系;最后,着重对易被混淆的孔隙流体压力符号的正方向和含义,以及基本方程中部分参数的定义式进行了讨论,有助于更好地理解、应用Biot理论和修正的Biot理论。
关键词:Biot理论;修正的Biot理论;弹性系数;应力;孔隙流体压力;参数
基金项目:国家自然科学基金(U1234204,51378463)
收稿日期:2013-06-26修改稿收到日期:2014-01-28
中图分类号:TU435文献标志码: A
Comparison and discussion for Biot theory and modified Biot one
LIUZhi-jun1,2,XIATang-dai1,2,HUANGRui1,2,CHENWei-yun3(1. MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering, Zhejiang University, Hangzhou 310058, China;2. Research Center of Costal and Urban Geotechnical Engineering, Zhejiang University, Hangzhou 310058, China;3. College of Transportation Science & Engineering, Nanjing University of Technology, Nanjing 210009, China)
Abstract:The wave equations of Biot theory and modified Biot one were derived, and the dimension and correct definition of each parameter in the equations were clearly indicated. Based on the modified Biot theory, three different forms of wave equations were derived as well. Then, by comparing those two theories, the expressions of Biot elastic coefficients were obtained, and the stresses of the two theories and their correspondences were analyzed. Finally, particularly, the positive direction and meaning of pore-fluid pressure sign and the definitions of part parameters in the fundamental equations were discussed to be helpful for understanding and using the two theories.
Key words: biot theory; modified biot theory; elastic coefficients; stress; pore-fluid pressure; parameters
20世纪50年代,Biot[1-2]首先建立了流体饱和多孔介质传播理论(简称“Biot理论”),其基本方程已得到广泛应用,为双相多孔介质的土动力学分析奠定了基础。Biot理论是基于热力学原理而推导出的半唯象(semi-phenomenological)理论,其中,A、R、Q 等系数太复杂且含义抽象,给实际求解带来了困难。后来的学者对其进行了一些简化和修正,提出了可以考虑固体颗粒和流体压缩性、且忽略质量耦合系数的双相孔隙介质理论(“修正的Biot理论”),其基本方程的建立是基于弹性动力学和渗流理论,易于理解,也在一定程度上证实了Biot理论的正确性。……
