新疆大河沿水库大坝填筑料工程特性研究  

Engineering Characteristics of Back Fill Materials for Xinjiang Daheyan Reservoir Dam

作　　者：喻济时 YU Jishi(Hunan Water Resources and Hydropower Survey,Design,Planning and Research Co.Ltd.,Changsha 410007)

机构地区：[1]湖南省水利水电勘测设计研究总院,长沙410007

出　　处：《土工基础》2021年第4期535-538,共4页Soil Engineering and Foundation

摘　　要：新疆大河沿水库大坝设计拟定沥青心墙堆石坝,最大坝高77.7 m。工程区构造稳定性差,地震基本烈度为Ⅶ度区,需综合评价大坝填筑砂砾石的工程特性,为后期堆石坝稳定性计算提供数据支撑。结果表明,大坝填筑料在100~200 kPa范围内压缩系数为0.036~0.060 MPa^(-1),反应该填筑料为低压缩性土;大坝填筑料渗透系数为3.8×10^(-2)~4.5×10^(-2) cm·s^(-1),表明该填筑料具有自由排水性能;大坝填筑料有效内摩擦角接近42°,具有较高的抗剪强度,抵抗变形的能力强;Duncan-Chang模型能够较好描述大坝填筑料偏应力-轴向应变关系,在体应变-轴向应变关系描述上与试验值偏离较大。The dam of the Daheyan Reservoir was designed to be an asphalt concrete cored rock fill dam with a maximum height of 77.7meters.The structural geological stability of the project area is classified as Poor,and the design seismic intensity belongs ZoneⅦ.Therefore,it is necessary to conduct a comprehensive evaluation of the engineering characteristics of the dam back fill materials for the dam stability analyses.The results indicate that the coefficients of compressibility of the back fill material are between 0.036and 0.06 MPa^(-1) under the pressure of 100~200kPa,which indicating a low compressibility material property.The permeability coefficients of the tested materials are in the range of 3.8×10^(-2) to 4.5×10^(-2)cm·s^(-1),which means that the material is a free-drain back fill material.The tested internal friction angle of the material is nearly 42°,which illustrates a high shear strength property.The Duncan-Chang model could better describe the deviatoric stress-axial strain relationship.Whereas,the differences between the prediction model and tested data of the volume strain-axial strain relationship of the back fill materials are relatively large.

关 键 词：大坝填筑料 压缩系数 渗透系数 抗剪强度 DUNCAN-CHANG模型 

分 类 号：TU443[建筑科学—岩土工程]