面板堆石坝混凝土面板脱空影响因素敏感性分析  

Sensitivity analysis of influencing factors of separation between concrete face and cushion layer of CFRD

作　　者：李炎隆[1] 卜鹏 吴海波 温立峰[1] 周恒[3] 陆希[3] LI Yanlong;BU Peng;WU Haibo;WEN Lifeng;ZHOU Heng;LU Xi(State Key Laboratory of Eco-hydraulics in Northwest Arid Region,Xi'an University of Technology,710048 Xi'an,China;Gansu Water Conservancy and Hydropower Survey and Design Research Institute Co.,Ltd.,730000 Lanzhou,China;Power China Northwest Engineering Corporation Limited,710065 Xi'an,China)

机构地区：[1]西安理工大学省部共建西北旱区生态水利国家重点实验室,西安710048 [2]甘肃省水利水电勘测设计研究院有限责任公司,兰州730000 [3]中国电建集团西北勘测设计研究院有限公司,西安710065

出　　处：《应用力学学报》2022年第6期1108-1116,共9页Chinese Journal of Applied Mechanics

基　　金：国家自然科学基金资助项目(No.51979224,No.51909215);西安理工大学博士学位论文创新基金资助项目(No.252072020)。

摘　　要：面板脱空的根本原因是面板与垫层之间的不协调变形,为了探究坝址区地形地质条件及库水位循环升降对面板脱空的敏感性,本研究采用子模型法准确模拟了面板脱空区域的力学响应特性,基于相对变位法研究了河谷宽高比T、覆盖层厚度F及水库水位循环升降次数K对混凝土面板脱空的敏感性。研究结果表明:混凝土面板脱空特征值的扩展会随三者的增大呈对数形式增长,其中,河谷宽高比T的增大削弱了河谷地形对坝体的约束,从而促进了面板脱空的发展,但当河谷宽高比T大于2.0时,其对面板脱空的敏感性会显著降低;覆盖层厚度F的增加促进了坝体的不均匀沉降,进而导致面板脱空区域向底部扩展,但面板脱空对覆盖层的敏感性会随着覆盖层厚度F的增加而降低;由于面板与堆石体变形特性的差异,在水库水位循环升降作用下,面板脱空区域缓慢扩展,并最终趋于稳定;三者中,F对面板最大脱空深度的敏感性最高,T对顺坡向脱空长度的敏感性最高。本研究成果可为面板脱空问题的防治提供相应的理论依据。The essential cause of the separation between concrete face and cushion layer is the uncoordinated deformation between concrete face and cushion layer.In order to explore the influence of topographical and geological conditions in the dam site and the cyclic rise-fall of reservoir water level on the separation between concrete face and cushion layer,we use the sub-model method to accurately simulate the mechanical response characteristics of slab void area in this paper,and then explore the sensitivity of width-to-height ratio of valley T,overburden thickness F and cyclic rise-fall times of reservoir water level K on the separation between concrete face and cushion layer based on the relative displacement method.The results show that the characteristic value of separation between concrete face and cushion layer increases logarithmically with the increase of the three.The increase of the width-to-height ratio of valley T weakens the constraint of valley topography on dam body,thus promoting the development of the separation between concrete face and cushion layer.However,when the width-to-height ratio of valley T is greater than 2.0,its sensitivity on separation between concrete face and cushion layer is significantly reduced.The increase of the overburden thickness F promotes the nonuniform settlement of the dam body,and causes the area of separation between concrete face and cushion layer to gradually expand to the bottom.On the other hand,the sensitivity of the separation between concrete face and cushion layer decreases as the thickness of the cover layer increases.At the same time,due to the difference in deformation characteristics between the concrete face and the rockfill,the area of separation between concrete face and cushion layer expands slowly under the action of the cyclic rise-fall of reservoir water level and eventually stabilizes.Among the three,F has the highest sensitivity to the maximum depth of separation of concrete face and T has the highest sensitivity to the downhill length of separation.T

关 键 词：混凝土面板脱空 敏感性分析 河谷宽高比 覆盖层厚度 水库水位循环升降 

分 类 号：TV641.4[水利工程—水利水电工程]