拱坝温度荷载与温度应力的考虑

介绍拱坝温度荷载的概念及值得注意的问题 .拱坝的温度荷载可以分解为三部分 :均匀温度变化Tm,等效线性温差Td 及非线性温差Tn.拱坝有封拱温度场、年平均温度场和变化温度场三个特征温度场 ,其温度荷载可由特征温度场的相应值求得 .文章还介绍了用拱梁分载法计算拱坝温度应力 ,同时论述了影响拱坝温度应力的一些因素 ,包括封拱温度、坝体及基础弹模、坝体热胀系数及导温系数、坝体表面温差等 .

Consideration of Temperature Loads on and Stresses of Arch Dams

The concept of temperature loads on arch dams is introduced and some important problems are proposed. The temperature loads can be divided into three parts: mean temperature variation T m, equivalent temperature difference T d, and non-linear temperature difference T n. There are three kinds of characteristic temperature fields: joint grouting temperature field, annual mean temperature field, and the variable temperature field. The temperature loads on arch dams can be obtained according to the corresponding value of each temperature field. In the second part of the paper, the calculation of temperature stresses of arch dams by means of the trial-load method is presented, and some factors affecting the temperature stresses are discussed, such as the joint grouting temperature, the elastic modulus of the dam body and foundation, the thermal expansion coefficient and the isotherm coefficient of the dam body, and the temperature difference of the dam surface.