模型试验的分离相似设计方法——以锚索格构加固边坡模型试验为例

Isolated similar design method for a scaled model test and its application to slope-anchor cable-lattice beam system

提出了模型试验的分离相似设计方法,以锚索、格构梁加固边坡振动台试验为例进行介绍。将传统量纲分析法中描述振动台试验各个相关参数之间关系的函数关系式定义为1级特征方程。根据边坡、锚索、格构和地震波特性的不同,将1级特征方程进行分离处理,得到分别用于边坡、锚索、格构和地震波相似设计的2级特征方程。根据每个2级特征方程中参数的重要程度不同,将关键设计参数从2级特征方程中分离出来,组成3级特征方程。根据3级、2级和1级特征方程可以分别推导得到针对边坡、锚索、格构梁和地震波各自的关键参数、相关参数和无关参数相似比,选择关键参数相似比作为模型设计的主要依据,并对试验模型进行了相似设计。解决了按照传统量纲分析法要求,模型试验无法同时满足所有参数相似比要求的问题。

An isolated similar design method is developed for a scaled model test, and then is applied to simulate a shaking table test for the slope-anchor cable-lattice beam system. The functional equation of dimensional analysis is defined as the primary characteristics equation, which is used to describe the relationship of variables in the shaking table test. According to the difference of characteristics of the slope, anchor cable, lattice beam and seismic wave, all the system variables can be divided into four sections, which is further used to derive the scaling relations for the slope, anchor cable, lattice beam and seismic wave. The functional equations for characterizing the scaling relations for these four sections are the secondary characteristics equations. The importance degree of variables in the secondary characteristics equation is different for the scaled model. The functional equations used for characterizing the scaling relations of more important factors are the tertiary characteristics equations. Based on the tertiary, the secondary and the primary characteristics equations of these four sections, the scaling relations for the primary variables, relevant variables and irrelevant variables can be derived, respectively. Then the primary variables are selected to design the scaled model. The problems that all the scaling relations in the previous studies cannot be satisfied in the scaling model have been resolved.