水工混凝土结构温度应力约束系数研究  

Research on temperature stress constraint coefficient of hydraulic concrete structure

作　　者：杨志华 李海枫[2] 胡永林 YANG Zhihua;LI Haifeng;HU Yonglin(China Railway Water Conservancy&Hydropower Planning and Design Group Limited Company,Nanchang 330029,China;China Institute of Water Resources and Hydropower Research,Beijing 100038,China)

机构地区：[1]中铁水利水电规划设计集团有限公司,江西南昌330029 [2]中国水利水电科学研究院,北京100038

出　　处：《中国水利水电科学研究院学报(中英文)》2025年第2期121-130,共10页Journal of China Institute of Water Resources and Hydropower Research

基　　金：中国中铁股份公司科技研究开发计划项目(2022-重大-08);国家重点研发计划项目(2016YFC0401807)。

摘　　要：应力约束系数是水工混凝土结构温控设计与计算分析中非常重要的参数,其合理取值直接关系基础容许温差选取,进而影响到容许最高温度确定和浇筑温度拟定。关于应力约束系数取值,现有规范仅对坝工等大体积水工结构有所规定,而对软基上的水工混凝土结构没有提及;另外,《混凝土坝温度控制设计规范》仅给出H=L取值,对于H≠L或基岩弹性模量和混凝土弹性模量相差较大时,该规范没有明确规定;上述问题本质上是不同弹性模量比和不同宽高比下浇筑块约束系数R的取值问题。为此,本文基于有限元法开展不同弹性模量比和不同宽高比下均匀冷却时浇筑块温度应力及约束系数研究。研究成果表明:约束系数R随弹性模量比E_c/E_R呈负相关变化而随宽高比L/H呈正相关变化,该变化趋势可采用改进后的复合指数函数式进行拟合;该拟合公式能够同时考虑弹性模量比值E_c/E_R和宽高比L/H的综合影响,可为不同弹性模量比和不同宽高比浇筑块的约束系数取值提供依据;进行水工混凝土结构温控设计时,混凝土坝的约束系数可按照规范规定进行取值,岩基上其他大体积混凝土结构的约束系数可由该拟合公式计算得到,软基上水工混凝土结构的约束系数建议取0.1。Stress constraint coefficient is a very important parameter in the temperature control design and calculation analysis of hydraulic concrete structure,and its reasonable value is directly related to the selection of the permissible temperature difference of the foundation,which in turn affects the determination of the maximum permissible temperature and the formulation of the pouring temperature.Regarding the value of stress constraint coefficient,the existing specification only provides for large volume hydraulic structures such as dams,and does not mention hydraulic concrete structures on soil or soft foundation;in addition,the Design Code for Temperature Control of Concrete Dams only gives the value of H=L,and it does not specify the value of H≠L or the modulus of elasticity of bedrock and the modulus of elasticity of concrete.The above problem is essentially a problem of taking the value of constraint coefficient R of casting block under different modulus of elasticity ratio and different width-to-height ratio.Therefore,based on the finite element method,this paper studies the temperature stress and constraint coefficient of the cast block under uniform cooling with different elastic modulus ratio and different aspect ratio.The results show that the constraint coefficient R is positively correlated with the elastic modulus ratio E c/E R and negatively correlated with the aspect ratio L/H.The change trend can be fitted with the improved composite exponential function.The fitting formula can consider the combined effects of the elastic modulus ratio E c/E R and the aspect ratio L/H at the same time,and can provide a basis for the value of the constraint coefficient of the cast block with different elastic modulus ratio and different aspect ratio.When designing the temperature control of hydraulic concrete structure,the constraint coefficient of concrete dam can be calculated according to the specification,and the constraint coefficient of other large volume concrete structures on rock foundation can be calcul

关 键 词：水工混凝土 温度应力 约束系数 有限元 弹性模量比 宽高比 

分 类 号：TV431[水利工程—水工结构工程]