【摘要】 结合龙滩高碾压混凝土重力坝的设计和施工组织安排,进行了坝体最不利长间歇仓面和在长间歇期间遭遇坝区最大一次寒潮冷击的坝体温度应力的三维有限元仿真计算。计算结果表明,在不利高程262m仓面长间歇不会导致混凝土裂缝的产生;但是,如不采取任何温控措施,寒潮冷击必然会给坝体上下游面带来破坏性的影响,比如坝上游面劈头缝的产生。经对寒潮来临前采取不同保温措施的温度应力计算分析,建议在低温季节来临前就应适时采取2 5cm厚的泡沫塑料板进行坝体表面保温。另外,龙滩大坝还需采取综合性的温控防裂措施,以确保大坝不裂。更多还原

【Abstract】 According to the conditions of the design and construction plan of the Longtan high RCC gravity dam in China,the authors in this paper carried out the 3D finite element emulative analysis of the temperature field and thermal stress field of the dam during a long time cease of concrete placement and a worst cold wave strike. In line of the results a 60day long downtime couldn’t directly causes the cracks in the dam,even if the cease location has been selected at the worst elevation of 262 m. But if any thermal control measure will not be adopted before the cold wave comes,the dam must definitely be cracked by the strike of the cold wave,especially on both of the upstream and downstream surfaces of the dam. The most concerned head split cracks might take place inevitably. After the numerical calculation of the dam stresses under the conditions of using different thermal saving covers for the dam,the authors want here to suggest that the parts of the dam surfaces should be covered by thermal saving plastic plates with a thickness of 2.5 cm at an appropriate time before the low temperature season comes. Finally,taking into account the results calculated,one needs comprehensive temperature control and cracking prevention measures for the dam,in order to grantee that the dam will not be cracked.更多还原