摘要
在大坝的施工期通水冷却中,选取合适的温控参数可以降低开裂风险。采用三维有限元法,分析了三河口碾压混凝土高拱坝5号坝段的通水冷却措施。分析过程中,控制的变量有一期冷却水温度、二期冷却水温度和二期冷却开始时间。通过对不同工况特征点的温度、应力发展过程线的分析,得到一期通水温度每降温1℃温度应力减小约0.06 MPa,二期通水温度每降低1℃温度应力增加约0.12 MPa,延迟二期冷却开始时间可降低温度应力。综上,可采用降低一期冷却通水温度,严格控制二期冷却水温并适当延迟二期通水冷却龄期的措施来优化通水冷却措施。
In the water cooling during the construction period of dam,proper temperature control parameters shall be selected to reduce the risk of cracking.The three-dimensional finite element method is used to analyze the water cooling measures in the No.5 dam section of Sanhekou RCC high arch dam.During the analysis,the first-stage cooling water temperature,the second-stage cooling water temperature and the second-stage cooling start time are selected as the control variables.Through the analyses of the temperature and stress development process lines at the characteristic points of different working conditions,it is obtained that the temperature stress decreases by 0.06 MPa for every 1℃drop in the water flow temperature in the first phase and increases by 0.12 MPa for every 1℃drop in the water flow temperature in the second phase,and the delay of the second-stage cooling start time can reduce the temperature stress.In summary,the measures of reducing first-stage temperature,strictly controlling second-stage cooling water temperature and appropriately delaying the start time of second-stage can be used to optimize the water-cooling process.
作者
赵一鸣
王振红
汪娟
李辉
ZHAO Yiming;WANG Zhenhong;WANG Juan;LI Hui(State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin,China Institute of Water Resources and Hydropower Research,Beijing 100038,China)
出处
《水力发电》
CAS
2021年第10期45-50,74,共7页
Water Power
基金
国家重点研发计划项目(2018YFC0406700)
国家自然科学基金资助项目(51779277)
中国水科院科研专项(SS0145B71-2017,SS0145B612017,SS0145B392016)。
关键词
大体积混凝土
施工
通水冷却
温度场
应力场
仿真计算
mass concrete
construction
water cooling
temperature field
stress field
simulation calculation
