摘要
针对小湾拱坝左、右岸坝肩抗力体内存在的地质缺陷,采用超载方法,对小湾拱坝1210m高程进行坝肩稳定平面地质力学模型试验。试验重点模拟主要断层、蚀变带、软岩带以及坝肩SN,EW向2组主要节理;得出坝体位移、应变,坝肩位移、破坏过程、破坏形态和超载安全系数,对坝肩稳定性进行评价。由于地质力学模型缩尺后无法模拟坝肩岩体中的密集节理,为了探讨密集节理对坝肩稳定的影响,采用非线性有限元对考虑和不考虑密集节理2种情况进行计算分析,通过对比计算结果得出,密集节理对坝体、坝肩位移的影响为-8%～10%、对超载安全系数的影响约为-9%,说明密集节理对小湾拱坝1210m高程坝肩稳定的影响程度不大,试验成果是可靠的。
According to the geological defects in abutment of Xiaowan arch dam,the plane geomechanical model test based on overload method was carried out to research the abutment stability of typical elevation 1 210 m. In the test,the main fault,altered zone,soft rock zone and the two groups of joints tending to SN and EW were simulated,and the displacement and strain of the dam,the abutment displacement,the failure process,failure modes,as well as the overloading safety coefficient were obtained. So the dam abutment stability could be evaluated. As the result of geomechanical model test was an experimental method,which was based on the principle of geometric similarity and the mechanical similarity reduced the scale of dam and foundation,the model can not simulate the dense joints contained in abutment rock. In order to analyze the influence of the dense joints, the nonlinear finite element method was adopted to research abutment stabilities with and without dense joints. The results show that the impact of displacement of dam and abutment is about-8%–10%,and the impact of overload safety coefficient is about-9%. Therefore,even the model test could not simulate the dense joints contained in dam abutment,the impact of the dense joints in the abutment at elevation 1 210 m of Xiaowan arch dam is small,and the results of the model test are reliable.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2010年第A02期3972-3978,共7页
Chinese Journal of Rock Mechanics and Engineering
基金
国家自然科学基金资助项目(50879050)
关键词
水利工程
拱坝坝肩稳定性
地质缺陷
密集节理
模型试验
有限元计算
hydraulic engineering
arch dam′s abutment stability
geological flaw
dense joints
model test
finite element calculation
