后张法现浇预应力箱梁起拱与下挠的施工控制.pdf

施工技术 2012年11月下 30 CONSTRUCTION TECHNOLOGY 第41卷第377期 后张法现浇预应力箱梁起拱与下挠的施工控制 贺洪儒，宋伟明，邱永会 (中交二航局第二工程有限公司质量检测所，重庆400016) [摘要]针对现浇箱梁施工各环节产生结构起拱和下挠影响因素的研究，得出通过采取预设一定反拱度、采取高性 能混凝土和高性能浆液、提高桥梁钢筋及预应力体系的安装定位精度以及混凝土和孔道压浆的精细化施工等措 施，减少混凝土的收缩徐变，提高混凝土匀质性和整体性能，使箱梁起拱和下挠控制在合理范围内，使桥梁结构的 耐久性和使用寿命得到保证. [关键词]混凝土；箱梁；预应力；起拱；下挠；施工控制 [中图分类号]TU755;TU448 [文献标识码]A [文章编号]1002-8498(2012)22-0030-03 Construction Control of Arching and Downward Deflection for Cast-in-place Box-girder with Post-tensioning Method He Hongru Song Weiming Qiu Yonghui (Inspected Department The 2nd Engineering Co.Ltd.of CCCC Second Harbour Engineering Co.Ltd.Chongqing 400016 China) Abstract:Based on the research of factors influencing the arching and downward deflection of cast-in- place box-girders at each construction stage a series of construction measures are proposed.They include pre-setting certain anti-arch degree use of high performance concrete and high performance slurry improving the installation and positioning accuracy of steel reinforcements and pre-stress system of the bridge refining the construction for concrete and duct grouting etc.These measures can reduce the concrete shrinkage and ereep improve the concrete uniformity and integrity control the arching and downward deflection of cast-in-place box-girders within a reasonable range and guarantee the bridge durability and service life. Key words:concrete;box-girder;prestressing;arching:downward deflection;construction control 1工程概况 配制具有良好体积稳定性的高性能混凝土，确 泰州长江公路大桥接线工程（泰...