摘要
超长多跨连续梁桥通长预应力束张拉施工复杂,对梁体内力影响较大,预应力损失难以控制.以子牙河特大桥十三孔预应力混凝土道岔连续梁桥为研究对象,通过理论研究和现场预应力张拉施工过程中的梁体应力测试,对应力的分布规律进行研究.结果表明:通长预应力束分段张拉引起的梁体应力分布较均匀,预应力损失小;第n段预应力张拉对n-1段梁体应力影响较大,对其余梁体应力影响较小;通长预应力束一次张拉引起的梁体应力分布呈中间小两端大的趋势,梁体中部预应力损失较大;采用分段张拉的方法能够有效减少预应力损失.研究成果对相关工程的设计与施工具有参考价值.
The construction of continuous prestressing tendons stretching for super long and multi-Span Continuous Beams Bridge is complex and has great influence on the stress of beam, and the prestressed loss is difficult to control. Taking the prestressed concrete continuous beam of the Zi ya River huge bridge with thirteen holes as the research object, our study focuses on the distribution law of stress through the theoretical research and the stress test in the construction of fully long prestressing tendons Stretching. The study result shows that： the stress caused by fully long prestressing tendons sectional tendons stretching distributes uniformly, and the prestressed loss is less. The prestressed tension of the n-section girder has more influence on the stress than n-1 section girder and less influence on other stress of girders.The distribution trend of the stress caused by fully long prestressing tendons Stretching at a time is little in the middle of the beam and large in the both ends, and the prestressed loss is larger in the middle of the beam; The method of sectional stretching can effectively reduce the loss of prestress. The results of the research can provide important reference for the similar engineering designs and constructions.
出处
《天津城建大学学报》
2015年第6期404-407,共4页
Journal of Tianjin Chengjian University
基金
住建部科学技术项目(2015-k3-021)
天津市自然科学基金(13JCYBJC19600)
天津市交通运输委员会科技项目(2014-23)
关键词
超长多跨
分段张拉
应力监测
预应力损失
super long and multi-span
sectional stretching
stress monitoring
prestressed loss
