摘要
竖向预应力损失过大和分布不均是引起箱梁桥腹板开裂的重要原因。基于理论分析与试验研究,针对竖向预应力分段张拉、现行的施工工艺缺陷造成竖向正应力分布不均和预应力损失过大的问题,提出滞后张拉、二次张拉概念、拉伸-扭矩法张拉工艺,以及三者结合的悬臂箱梁桥竖向预应力施工流程,并在实桥应用中取得良好的效果。研究成果可为类似工程竖向预应力施工提供参考。
Too much loss and uneven distribution of vertical prestressed are important reasons that cause cracking in webs of box beam bridges. Based on theoretical analysis and test study, such problems because of sequential segmental stretching mode, disadvantage of present stretching technique, are analyzed. Subsequently, concepts of lag-tension and two-times tension, stretchtorque constructing technique, further the technological process of combination utilization of three of them, are presented in order to alleviate or avoid those problems. Practice of such method leaded to good effect. The research can be reference for construction of vertical prestressed bars of similar engineering.
出处
《建筑结构》
CSCD
北大核心
2008年第12期73-76,55,共5页
Building Structure
基金
国家自然科学基金资助(50478099)
湖南省教育厅资助科研项目(06C311)
关键词
腹板开裂
预应力损失
滞后张拉
二次张拉
拉伸-扭矩法
cracking in webs
loss of prestressed
lag-tension
two-times tension
stretch-torque technique
