面板堆石坝垫层料渗透特性试验的影响因素探究

Study on Factors Affecting Permeability Tests of Materials for CFRD Bedding Cushion

面板堆石坝垫层区是面板的直接支承体,向堆石体均匀传递水压力,并起辅助渗流控制作用。垫层料渗透特性参数作为大坝渗流计算和渗透稳定性分析的重要指标,主要通过试验取得。目前不同科研单位的试验结果表现出较大的差异性,综合分析认为与试验测试方法有关。文章从试样级配、制样密度、试样边界条件以及试验渗流方向等诸多方面,通过设计不同的试验组合比对方案,对可能的影响因素进行分析论证,探究造成垫层料渗透试验结果差异较大的主要原因,为针对实际工况选择合理的试验方法提供参考。

The bedding-cushion zone of CFRD is the direct bearing base of surface slab. It uniformly transfers hydraulic pressure to the rockfill body and additionally controls seepage as well. As the important indicators for dam seepage calculation and permeable stability analysis, parameters of permeability of materials for bedding cushion are mainly achieved from tests. Currently, test results by different scientific and research institutes are largely different. Through comprehensive analysis, it considers that this large difference is related to test methods. To explore causes for the large difference of these results, in this paper, possible affecting factors are analyzed and demonstrated from possible aspects of sample gradation, sample density, sample boundary conditions and test seepage direction, etc. through alternatives for comparison of different test combinations. This provides selection of reasonable test methods based on actual operating condition with reference.