堆石料流变的特性研究与反分析

根据堆石料流变的机理分析,认为在力的持续作用下,细化破碎的堆石颗粒滑移充填孔隙是发生蠕变的主要原因,形成对堆石料流变本质的新认识。通过试验比较分析,三轴流变试验和一维蠕变试验对于堆石料流变规律的描述是基本一致的,并与应力状态和时间因素相关,但流变参数却难以通过试验确定。根据4参数堆石料流变(蠕变)关系式和双屈服面弹塑性模型硬化规律随时间的变化,对坝体原型观测资料进行反馈计算确定流变参数。说明采用反馈分析方法是研究堆石料流变参数的有效途径。

Study and Inversion of Rheological Properties of Rockfill

According to the analysis of creep mechanism of rockfill, it is concluded that the main factor causing the creep strain is the filling of pores among the rockfill with broken coarse materials under continuous compression. Some new results are obtained for the creep strain of rockfills. Basically, the rheological rules are the same with tri-axial rheological test and one-dimensional creep test corresponding to the stress state and time factor, but the rheological parameters could hardly be determined by test. Some rheological parameters are determined by back calculation of observation in site, in accordance with the creep relations with four parameters and the time variation in hardening rules of double yield surface elasto-plastic model. It shows that feed-back analysis is an effective method in study of the rheological parameters of rockfills.