南水北调工程河南庞村钢管混凝土无推力系杆拱桥项目设计采用C50高强、微膨胀、自密实混凝土灌注施工，混凝土灌注施工工艺为顶升法。通过优选骨料级配、使用微膨胀剂、高效减水剂等措施优化混凝土配合比，制备出性能参数符合顶升法施工要求的C50自密实钢管混凝土。混凝土灌注施工中，通过控制混凝土生产和运输，保证混凝土的连续灌注；通过清洗钢管、预灌砂浆、灌注节奏的控制，保证了混凝土与钢管的黏结与饱满；通过覆盖湿润的养护布连续养护14 d，保证了钢管混凝土的强度的顺利发展，通过以上措施的综合应用，经敲击法检验，混凝土于钢管内黏结牢靠、无缺陷、强度发展正常。%Pang village steel tube-confined concrete without thrust tied arch bridge project in Henan of South to North Water Diversion Project design pouring construction by using the C50 high strength,micro expansive,self-compacting concrete,the construction tech-nology of concrete pouring for lift-up method. Through optimizing aggregate gradation,using micro expansive agent and superplastici-zer and other measures to optimize mix of concrete,prepared C50 self-compacting steel tube-confined concrete,whose performance parameters meet the requirements of the lift-up method construction. In concrete pouring construction,through the control of concrete production and transportation to guarantee continuous pouring concrete. Through cleaning pipe,pre-pouring mortar,controlling perfu-sion rhythm to ensure the bond between concrete and steel tube with full. Through covering wet curing cloth and continuous curing 14 d to guarantee the smooth development of the strength of the steel tube-confined concrete. Through the integrated application of the a-bove measures,the concrete in steel tube bonds solid,no defects,strength normal development by the percussion method testing.
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