摘要
我国西南岩溶山区是世界上最大的连片裸露岩溶地区,地质环境脆弱,人类工程活动强烈,群死群伤的灾难性滑坡频发,巫峡地区的岩溶岸坡发育尤为突出。由于三峡库区蓄水及库水位波动,部分岩溶岸坡(如箭穿洞)发生了不同程度的变形与失稳,极大地影响了水库的安全运行。为了确定巫峡岩溶岸坡箭穿洞地质力学模型试验结构面相似材料的最佳配比,以重晶石粉、石英砂、石膏和水为原料配置结构面相似材料,基于正交试验设计方法开展相似材料配比试验研究。以骨胶比(骨料/胶结剂)、水膏比(水/石膏)、重骨比(重晶石/骨料)为三个控制因素,开展三轴压缩试验,获得不同配比相似材料的力学指标。通过采用模糊综合评判法获得最佳相似材料配比并开展岩体结构面黏结材料相似性模拟试验,同时,在不同正交设计水平条件下各控制因素对不同物理力学参数进行敏感性分析。研究结果表明:不同配比相似材料的力学参数分布范围较大,劣化效应明显,能够满足地质力学模型试验结构面相似材料的基本特征要求;相似材料的密度和内摩擦角主要受骨胶比控制,黏聚力主要受水膏比控制。此研究成果可为后续地质力学模型试验的顺利进行提供一定的理论依据和实践经验,为三峡库区防灾减灾与预警评估提供基础理论支撑,从而提升我国岩溶山区地质灾害防灾减灾的能力。
The karst mountain region in the Southwest China is the largest contiguous exposed karst area with fragile geological environment in the world,especially the development of the karst bank-slope within the area of Wuxia Gorge is quite prominent.Due to the impoundment of Three Gorges Reservoir and the fluctuation of the reservoir water level,the deformations and instabilities with different degrees occur at a part of the karst bank slopes(e.g.Jiangchuandong Rock Mass)therein,and then the safe operation of the reservoir is greatly impacted.In order to determine the optimum mixing ratio of the material that is similar to the structural plane for the geomechanical model experiment on Jiangchuandong Rock Mass of the karst bank-slope within the area of Wuxia Gorge,barite powder,quartz sand,gypsum and water are taken as the raw materials for preparing the similar material for the structural plane;for which the experimental study on the mixing ratio of the similar material is carried out based on the design method of orthogonal experiment.By taking aggregate-cement ratio(aggregate/cementing agent),water-gypsum ratio(water/gypsum),barite powder-aggregate ratio(barite powder/aggregate)as three control factors,the relevant triaxial compression experiments are made,and then the mechanical indexes of the similar materials with different mixing ratios are obtained.Through fuzzy comprehensive evaluation method,the optimum mixing ratio of the similar material is obtained,and then the simulative experiment on the similarity of the bonding material for the rock mass structural plane is conducted as well.Meanwhile,the sensitivities of all the control factors under the conditions of different levels to different physical and mechanical parameters are analyzed.The study result shows that the distribution ranges of the mechanical parameters of the similar materials with different mixing ratios are larger with obvious degraded effects,and then can meet the requirements on the basic characteristics of the similar materials of the structu
作者
郭健
张鹏
黄波林
秦臻
GUO Jian;ZHANG Peng;HUANG Bolin;QIN Zhen(College of Civil Engineering & Architecture, China Three Gorges University, Yichang 443002, Hubei, China;Key Laboratory of Disaster Prevention and Mitigation, China Three Gorges University, Yichang 443002, Hubei, China)
出处
《水利水电技术》
北大核心
2020年第9期193-199,共7页
Water Resources and Hydropower Engineering
基金
国家重点研发计划项目(2018YFC1504803)
开放基金项目(2018KTL13/2017KJZ05)
国家自然科学基金青年科学基金项目“卡口地形段泥石流的堵溃效应研究”(41701013)。
关键词
相似材料
正交设计
岩溶岸坡
箭穿洞危岩体
similar material
orthogonal design
karst bank-slope
Jianchuandong Rock Mass
