岩体中弹性波传播尺度效应的初步分析

含缺陷岩体具有尺度效应，此类岩体中传播的弹性波也有尺度效应。对现场测点 EC37-201-06 ，在 3.0 ´ 3.2 m² 的范围内采用动态有限元方法进行了 15 种尺度的弹性波传播规律的分析研究。对现场测点 EC37-101-06 ，在 1.2 ´ 1.2 m² 的范围内采用准静态有限元方法进行了 60 种尺度的弹性波波速与围压及计算尺度的关系的计算分析。前者采用了射线理论分析思想，而后者采用等效介质分析思想，得到了相应的弹性波的尺度效应，但二者规律有差异。为建立二者间的联系，也为了工程应用，基于量纲理论分析方法，给出了一个半理论的波速与入射波频率的计算公式。与现场声波和地震波测试结果，以及考虑随机分布单节理散射模型的计算结果进行比较，初步分析结果表明，此公式基本可行。

A preliminary analysis of scale effect of elastic wave propagation in rock mass

The propagation rules of elastic wave in rock mass with defects take on scale effect, just like the rock mass. The dynamic finite element method (DFEM) is employed to investigate the propagation rules of elastic waves at site-EC37-201-06. The whole computation area is 3.0 ´ 3.2 m² and 15 kinds of computation scales are applied. A static finite element method (FEM) is used to study the relations of elastic wave velocities to the confined pressure and computation scales at site-EC37-101-06. The whole computation area is 1.2 ´ 1.2 m² and 60 kinds of computation scales are applied. The ray theory is used in the former method, and the effective media theory is used in the later. The scale effect of elastic waves is obtained, but there are differences for the two methods. To establish their relations and provide a simple model for engineering computation, a semi-theoretical phase velocity equation is proposed based on the dimensionless method. Compared with the in-situ sonic velocities, seismic velocities and velocities computed by the theoretical model with randomly distributed joints, the proposed equation can be well used in rock mass.