大坝温度及抗裂性能受通水冷却方式影响研究OA

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.