论文部分内容阅读
文章从大体积混凝土水化热效应对结构开裂的影响出发,分析了施工阶段大体积混凝土的温度场及温度应力分布规律。以石首长江大桥主墩承台为研究对象,根据混凝土材料特性、实际施工条件,利用大型有限元软件建立有限元模型进行仿真分析,研究在浇筑过程中混凝土的温度场及温度应力的分布规律。分析结果表明:各施工阶段结构温度应力安全系数较大,满足相应规范要求;承台在浇筑过程中,中心温度先升后降,在第3天时达到峰值,且内表温差随中心温度变而变化;承台早期应力由内表温差引起,集中于表面;由于混凝土收缩等因素影响,后期应力集中于结构中心,且随龄期增长不断增大。
Based on the influence of mass concrete hydration heat effect on structural cracking, the article analyzes the temperature field and temperature stress distribution law of mass concrete in construction stage. Taking the main pier cap of Shishou Changjiang River Bridge as the research object, according to the concrete material characteristics and the actual construction conditions, the finite element software was used to establish the finite element model for the simulation analysis. The distribution law of the temperature field and temperature stress of the concrete during pouring was studied. . The results show that the safety factor of structure temperature stress in each construction stage is relatively large, which meets the requirements of corresponding codes. During the pouring process, the center temperature first rises and then falls, reaches the peak value on the third day, and the temperature difference of the inner surface changes with the center temperature The stress of the cap was caused by the temperature difference of the inner surface and concentrated on the surface. Due to the influence of concrete shrinkage and other factors, the stress in the later stage was concentrated in the center of the structure and increased with age.