论文部分内容阅读
永定河倒虹吸方涵2004年3月份开始浇筑底板混凝土,4月上旬开始浇筑边墙和顶板。2004年4月16日发现边墙中部有竖向宽度不足0.2 mm的裂缝。17日开会布置防裂措施:请北京市水利规划设计研究院提出温控要求;请搅拌站立即做优化配合比的试验,从砂石级配、外加剂、掺合料多方面着手,降低水泥用量,压低水化温升,减缓升、降温速度;请施工单位在确保浇筑质量的同时,安排夜间气温较低时浇筑边墙顶板,做好温度测量和施工记录,进
Yongding inverted siphon culvert Fanghan March 2004 began pouring concrete floor, in early April began to pour side walls and roof. On April 16, 2004, it was found that cracks in the central part of the wall had a vertical width of less than 0.2 mm. 17 meeting arrangements anti-cracking measures: Beijing Institute of Water Resources Planning and Design Institute put forward the temperature control requirements; immediately mixing station to do the optimization mix test, from gravel grading, admixtures, admixtures in many aspects, reduce the cement Dosage, reduce hydration temperature, slow down the rate of rise and cool down; Please make sure the quality of pouring construction unit at the same time, arrange the night when the temperature is low, pour the roof wall, make temperature measurement and construction records, into