快速浇筑条件下混凝土坝早龄期开裂风险分析

Analysis on cracking risk at early age of concrete under rapid placement of concrete dam

以南水北调工程某混凝土重力坝施工为例,分析与探讨了不同浇筑层厚度、不同层间间歇期、不同浇筑温度等对混凝土坝早龄期温度与应力的影响,对早龄期混凝土的温度与应力特性和开裂风险进行了深入分析研究,并提出了相应的确保应力安全的防裂方法。研究内容为快速浇筑条件下大坝混凝土温度控制标准和温控措施的制定提供技术支持。

By taking the construction of a concrete gravity dam within the South-to North Water Transfer Project as a stufy case, the impacts from different thicknesses of concrete placing layers, different intermitted periods in-between interlayers of concrete placement, different concrete placing temperatures on the temperature and stress at the aerly age of concrete of the dam are ana- lyzed and discussed herein; in which the temperature and stress characteristics of the concrete at the early age as well as the cracking risk are deeply studied, and then the corresponding anti-cracking method to ensure the stress safety concerned is put forward. The study provides a technical support for establishing the concrete temperature control criteria and the relevant temperature control measures for the dam concrete under rapid placement.