混凝土坝后期水管冷却方式研究

Research on the type of post pipe cooling of concrete dams

近年在混凝土特高坝施工中,有些坝块经后期水管冷却之后在非基础约束区出现了贯穿性裂缝。通过大量分析计算之后得出结论,这种裂缝的出现与后期水管冷却方式有密切关系,然后提出避免出现这种严重裂缝的新的后期冷却方式:多次后期冷却和台阶形后期冷却,并对上述两种后期冷却方式的应力状态和优缺点进行了深入分析,给出了详细算例,说明其温度与应力变化规律。

The influences of the type of post pipe cooling on the stresses in concrete dams are researched.It is shown that the type of post pipe cooling has great influence on the stress of concrete dam and sometimes may lead to cracking.Two new types of post pipe cooling: the multi-stage in time post cooling and the multi-step in temperature post cooling are proposed.They can reduce the thermal stress a great deal.