超长超宽湖底隧道混凝土施工温度控制

TEMPERATURE CONTROL OF ULTRA-LONG-AND-WIDE UNDER LAKE TUNNEL DURING CONCRETE CONSTRUCTION PROCESS

超长超宽湖底隧道属于大体积混凝土,施工时受温度影响易开裂。为此,对混凝土拌制前、入模、浇筑等过程进行温控。研究表明采用冷水雾、片冰、遮阳、冷水冲淋、低温浇筑等方式,混凝土入模温度将低于28℃;在底板布设冷却水管,内表温差降低6℃,温度得以有效控制,为类似工程提供参考。

The ultra-long-and-wide underwater cast-in-situ tunnel belongs to mass concrete,featuring cracks under the temperature variation during construction.Therefore,measures were taken to control concrete temperature during process like before mixing,molding,and pouring.The results indicated that cold water mist,flake ice,shading,cold water showering,pouring under low temperature etc.can control concrete molding temperature below 28℃,moreover,temperature difference between inner and surface of concrete was reduced by 6℃,which effectively controlled temperature variation of concrete through setting cooling water pipe.