溢洪道闸墩薄壁混凝土置换加固温度应力分析及验证

Analyse and validate thermal stress to thin-walled replaced concrete of spillway pier

为论证置换表层混凝土方案的可行性,通过模拟溢洪道闸墩加固工程表层薄壁混凝土的浇筑施工过程,对混凝土的温度应力场进行了三维有限元仿真分析。分析表明:选择气温2℃～10℃左右的季节,采用2.5 m厚度的分仓浇筑方法施工,新浇薄层混凝土施工期温差在10℃以内,最大温度应力为1.41 MPa,满足规范要求。施工过程也验证新浇混凝土未出现裂缝。计算分析和监测均表明置换表层混凝土方案是可行的,研究成果可为类似工程加固设计提供参考。

To reason the feasibility of the scheme about the replacement cover concrete, this paper analyzes the thermal stress field by using 3D finite element simulation analysis to simulate the construction process of thin-walled cover concrete. The analysis indicated that the temperature difference of thin-walled new concrete was within 10 ℃ in construction period and the maximum thermal stress of it was 1.41 MPa, when the air temperature was around 2 ℃~10 ℃ and the thickness of sequence placing was 2.5 m. The results comforted code requirement, and it was validated that there were no cracks in the new concrete in construction period. The calculation analysis and monitoring result show that the scheme of replacing cover concrete is feasible. The results in this paper are valuable for design and construction in analogy project.