溪洛渡水电站导流洞衬砌混凝土夏季分期浇筑温控效果分析

Study of Effect of Thermal Control on Lining Concrete of Diversion Tunnel of Xiluodu Hydropower Station that Pouring Concrete by Stage in Summer

针对大断面水工隧洞衬砌混凝土夏季施工很容易出现温度裂缝的问题,以溪洛渡水电站导流洞工程为例,采用ANSYS有限元软件模拟分析了不同温控工况下不同浇筑方式对衬砌混凝土的温控效果,并给出合理的温控方案。结果表明,采用一次浇筑难以满足温控防裂要求,而采用分期浇筑衬砌混凝土体的温度没有明显变化,但可有效降低各代表点最大拉应力,尤其是衬砌混凝土中间点的第一主应力,使衬砌混凝土满足抗裂安全要求。推荐温控方案可满足衬砌混凝土温控防裂要求,且安全富裕不是很大,相对来说也较经济。

To solve the problem that temperature cracks appear easily on lining concrete construction in summer of the large section tunnel. Taking Xiluodu hydropower station diversion tunnel for an example, ANSYS finite element simula- tion software is used to analyze the temperature control effect in different pouring ways under different conditions, and the reasonable temperature control program is given. The results show that pouring whole in one time can not prevent tem- perature cracks~ the temperature changes little that pouring whole in twice time, but the maximum tensile stress of the representative points is reduced effectively, especially the first main stress of the middle point in lining concrete, which meets the requirements of prevention cracks for lining concrete. So, the lining concrete can prevent temperature cracks as the specification claim with the later pouring way, as well as there is no more excess security and it is relative economic.