大跨度连续箱梁桥零号块施工水化热监测与计算分析

Analysis of Hydration Heat Monitoring and Calculation on Zero-block Segment of a Long Span Continuous Beam Bridge during Construction

本文以富锦-绥滨松花江特大桥主桥160 m连续梁为依托工程,采用现场实测,结合有限元分析的方法,对箱梁0#块水化热温度场进行研究。结果表明：本文建立的有限元模型与实测结果吻合良好;大桥0#块各构件里表温差均小于25℃,满足规范要求,但底板水化热最高温度70.4℃,且在混凝土浇注完成后1~1.5 d温度达到最大值,是水化热温度裂缝重点控制部位,应加强底板钢筋配置或对底板底模采取一定的保温措施以降低里表温差。

Based on the Fujin-Suibin Songhuajiang Bridge Project,the method of combining finite element analysis and construction monitoring was used to study the temperature field of zero-block during high strength concrete pouring stage of box girder. The comparison of FEM analysis and measurement reflected that the FEM model established in this paper fitted well with the measured data,and results showed that the temperature difference between inside and outside the zero-block girder was less than 25℃ which met the specification requirements. While,the highest temperature of the bottom flange of the box girder was 70. 4℃,and reached the maximum within 1- 1. 5 days after finishing the pouring construction,which should be specified as the primarily control area for hydration heat temperature crack. Hence,enhanced reinforcement or heat preservation measures on bottom flanges should be taken to reduce the temperature difference.