大坝温度及抗裂性能受通水冷却方式影响研究  

Research on the influence of water cooling methods on the temperature and crack resistance performance of dams

作　　者：颜亮亮 刘云中 YAN Liangliang;LIU Yunzhong(Lianyungang Jinhe Water Conservancy Engineering Construction Supervision Co.,Ltd.,Lianyungang 222000,China)

机构地区：[1]连云港市金河水利工程建设监理有限公司,江苏连云港222000

出　　处：《江苏水利》2024年第10期24-27,31,共5页Jiangsu Water Resources

摘　　要：大坝在施工和服役期间,由于水泥水化热引起的内部温度变化,容易导致结构开裂,影响其长期稳定性和安全性。通过建立大坝数值模型,分析大坝混凝土温度应力和温度受通水冷却时间、冷却管布设方式以及通水分期的影响趋势,研究结果表明:减小冷却水管间距有利于控制混凝土的最高温度,减少温度应力,提升坝体抗裂能力;需结合工程现场实际情况选择一期通水水温时,在保证混凝土降温的同时,最大程度上减小水管附近温差,避免混凝土开裂;一期冷却时长控制在20d较为合理,既能有效控制温度和应力,又能平衡好开裂风险,确保大坝结构的长期稳定性和安全性;建议在冬季前对夏秋季高温阶段浇筑的混凝土合理开展中期冷却,确保在不增加早期阶段过多应力的前提下,最大程度地降低混凝土内部温度。During the construction and service period of a dam,internal temperature changes caused by cement hydration heat can easily lead to structural cracking,affecting its long-term stability and safety.By establishing a numerical model of the dam,the temperature stress and temperature of the dam concrete are analyzed to determine the influence trends of water cooling time,cooling pipe layout,and water staging.The research results show that reducing the spacing between cooling pipes is beneficial for controlling the maximum temperature of the concrete,reducing temperature stress,and improving the crack resistance of the dam body;When selecting the water temperature for the first phase of water supply based on the actual situation of the project site,it is necessary to ensure that the concrete cools down while minimizing the temperature difference near the water pipe to avoid concrete cracking;It is reasonable to control the cooling time of the first phase at 20 days,which can effectively control temperature and stress,balance the risk of cracking,and ensure the long-term stability and safety of the dam structure;It is recommended to carry out mid-term cooling for the concrete poured during the high-temperature stages of summer and autumn before winter,to ensure that the internal temperature of the concrete is minimized without increasing excessive stress in the early stages.

关 键 词：大坝 水泥水化热 温度应力 通水冷却 混凝土开裂 

分 类 号：TV554[水利工程—水利水电工程]