施工期混凝土高拱坝已灌区温度回升解析

针对施工期高拱坝已灌区温度回升的现象,结合建设中的溪洛渡特高拱坝已灌区温度回升值进行统计分析,以及将蓄水前的已灌区混凝土块近似简化为混凝土平板问题,基于混凝土天然冷却或回升理论对已灌区温度回升现象进行解析,分析表明,当前高拱坝的封拱温度低于坝址年平均气温,不可避免地出现坝址年平均气温向已灌区进行缓慢温度倒灌,而且已灌区温度回升理论值与实测温度回升值较接近,由此认为,当前施工期高拱坝已灌区温度回升,主要原因应为外界环境气温向已灌区混凝土块的温度缓慢倒灌.

TEMPERATURE REBOUND ANALYSIS OF THE IRRIGATED AREA OF A HIGH ARCH CONCRETE DAM UNDER CONSTRUCTION

For a temperature rebound in the irrigated high arch dam, a statistic analysis is carried out, with consideration of the temperature rebound values in the irrigated area about the extra high arch dam, Xi Luo Du which is under construction. The irrigated concrete block, without impounding water, is approximately simplified as a concrete slab, and the irrigated temperature rebound phenomenon is analyzed, based on the theory of the natural cooling or rebound of the concrete. It shows that the current high arch dam's closure temperature is lower than the dam site's average temperature, so the dam site's temperature inevitably would flow backward, slowly, to the irrigation area. Moreover, the theoretical temperature rebound value is close to the actual temperature rise in the irrigated area. Therefore, the main cause of the temperature rebound in the irrigated high arch dam is that the environment temperature flows backward, slowly, to the irrigation area.