高墩连续梁0号块托架反拉加载预压技术研究及应用

RESEARCH AND APPLICATION OF BACK-TENSION LOADING AND PRELOADING TECHNOLOGY FOR NO.0 BLOCK BRACKET OF CONTINUOUS BEAMS OF HIGH PIERS

大跨度预应力混凝土连续梁通常采用移动挂篮节段悬臂浇筑法施工,连续梁0号块施工以搭设支架为主,利用堆放砂袋、水箱注水或者预制混凝土块等施加荷载的方法进行预压。随着高墩连续梁施工的增多,0号块施工工法愈加成熟,对于高桥墩、地形复杂且无法搭设支架施工的0号块,采取销轴及对拉杆固定托架、多点千斤顶反拉预压的施工方法。以玉磨铁路温泉村大桥48 m+80 m+48 m悬灌连续梁0号块为例,阐述销轴及对拉杆固定托架、多点千斤顶反拉预压的施工技术,为今后类似高墩连续箱梁0号块托架预压施工提供经验。

Long-span prestressed concrete continuous beams are usually constructed by the cantilever casting method of mobile hanging basket segments.The construction of block 0 of continuous beams is mainly carried out by erecting brackets,which are carried out by stacking sand bags,water tank water injection or precast concrete blocks and other methods of applying loads.preload.With the increase of continuous beam construction of high piers,the construction method of No.0 block has become more mature.For No.0 block with high piers,complex terrain and no support for construction,the use of pin shafts,fixed brackets for tie rods,and multi-point jacks are used for pre-tensioning.Pressed construction method.This paper takes the No.0 block of the 48 m+80 m+48 m suspension-irrigated continuous beam of the Wenquan Village Bridge of the Yumo Railway as an example,and expounds the construction technology of the pin shaft,the fixed bracket for the tie rod,and the reverse tension and preloading of the multi-point jack.Provide experience in the preloading construction of box girder No.0 block bracket.