论文部分内容阅读
针对大断面水工隧洞衬砌混凝土易出现温度裂缝的问题,基于某水电站泄洪洞无压段衬砌混凝土施工过程所记录的洞内空气温度和混凝土温度,分析了洞室内空气温度变化规律,探究了空气温度、通水温度和浇筑温度对混凝土最高温度的影响,并利用有限单元法模拟混凝土温度变化过程,比较了混凝土温度计算预测值与实测值的差异。结果表明,洞内气温年变幅较大、波动明显,洞室连通状况对洞内气温影响较大,因而在地下洞室衬砌混凝土浇筑施工过程要考虑连通状况的影响;拟合得到的洞内空气温度变化曲线和混凝土浇筑温度、通水温度、空气温度对混凝土最高温度的影响关系曲线为模拟计算隧洞衬砌混凝土温度提供了参考,并为混凝土最高温度控制提供了量化指标。
Aiming at the problem of temperature cracks easily appearing in large section hydraulic tunnel lining concrete, based on the air temperature and concrete temperature recorded in construction process of non-pressure section lining concrete of spillway tunnel of a hydropower station, the variation law of air temperature in tunnel is analyzed, Temperature, pouring temperature and pouring temperature on the maximum temperature of concrete. The finite element method is used to simulate the temperature variation of concrete. The difference between predicted and measured values of concrete temperature is compared. The results show that the annual variation of air temperature in the tunnel is large and fluctuates obviously, and the connectivity of the tunnel has a great influence on the temperature in the tunnel. Therefore, the influence of the connectivity condition must be considered in the pouring of the lining concrete in the underground tunnel. The curves of air temperature and concrete pouring temperature, water temperature and air temperature on the maximum temperature of concrete provide a reference for simulating the temperature of tunnel lining concrete, and provide quantitative indexes for the maximum temperature control of concrete.