浇筑层厚对碾压混凝土坝温度场和应力场的影响

Influence of Pouring Layer Thickness on Temperature Field and Stress Field of RCC Dam

高混凝土坝浇筑时材料用量大、施工条件复杂、建设周期长,同时又需考虑温度控制、结构应力、施工环境等因素对坝体安全的影响。为此,以某工程碾压混凝土重力坝为例,采用三维有限元法,研究了不同的混凝土浇筑层厚度对大坝温度场与应力场的影响。结果表明,早期坝体内部的最高温度随浇筑层厚的增加而增大,坝体不同区域最高温度不仅受浇筑厚度的影响,同时也与大坝浇筑的时间相关;基础垫层混凝土、三级配碾压混凝土和二级配常态混凝土区域最大拉应力随浇筑厚度的增大而增大。

During the pouring of high concrete dam,the material consumption is large,the construction conditions are complex and the construction period is long.At the same time,it is necessary to consider the impact of temperature control,structural stress,construction environment on the dam body safety.Taking an engineering spillway as the research object,this paper adopts three-dimensional finite element method to study the influence of different thickness of concrete pouring layer on the temperature and stress filed of the dam.The results show that the maximum temperature inside the dam increased with the increase of the thickness of the pouring layer.The maximum temperature in the early stage of the dam increased with the increase of the pouring layer thickness,and the maximum temperature in different areas of the dam was not only affected by the pouring layer thickness,but also related to the pouring time of the dam.The maximum tensile stress in the area of third-grade RCC and second-grade normal concrete with foundation cushion concrete increases with the increase of casting thickness.