水管冷却控制地铁车站侧墙混凝土早期开裂研究

Early Age Cracking Control of Sidewall Concrete in Metro Station Construction by Using Cooling Water Pipe

通过试验测试与理论计算研究了水管冷却工艺控制地铁车站侧墙结构混凝土(采用C35P8混凝土)早期裂缝的可行性。结果表明,高温季节施工且分段浇筑长度较大时,地铁车站侧墙混凝土早期收缩开裂风险突出,工艺参数合理的水管冷却施工措施与抗裂混凝土技术协同采用,可显著降低结构混凝土早期收缩开裂风险系数且控制其低于0.7。对应用该技术施工的地铁车站侧墙实体结构温度、应变历程的监测结果表明,该方法切实有效。

The feasibility of early age cracking control of sidewall structure concrete in metro station construction by using cooling water pipe was researched through experimental test and theoretical calculation.The results indicated that the early age shrinkage cracking risk of sidewall concrete in metro station engineering was prominent under the condition of high temperature season and long lining length.The early age shrinkage cracking risk of structure concrete was decreased by more than 40%obviously and lower than 0.70 by the cooperatively adopting of cooling water pipe measure with reasonable technology parameters and anti-crack concrete technology.The temperature and strain history of actual sidewall structure using cooling water piper was monitored and the results showed that the application of cooling water piper reduced its early age temperature rise and shrinkage deformation at temperature drop stage effectively which helped eliminating cracks thoroughly.