铁道科学与工程学报2018，Vol.15Issue(5)：1255-1261,7.
既有结构改造加固的应力重分布研究
Study on the stress redistribution of existing structure rebuilding and reinforcement
摘要
Abstract
The phenomenon of stress redistribution caused by the reinforcement of existing buildings is remarkable. Relying on a practical project of demolishing the column and widening the span, the deflection and strain data of frame beam during both construction and operation period are collected. Comparing the data with the finite element parameters, and then it demonstrated that for the new section reinforced by enlarging section area, the stress of system transformation is greater than that of shrinkage and creep. The deflection and stress of the frame beam are increased to 2~3 times of the initial stage after 1 000 days. The structure reinforcement makes the frame beam central axis shift and the stress of the old section is retained before system transformation. The old and new concrete shrinkage and creep effect of reinforced section will make the stress of old concrete more than the initial stress of the structure system gradually. The stress accumulation effect of the buildings strengthened by demolishing the column and widening the span is significant. In fact, the maximum concrete stress at the bottom of the beam can be 2 times of a casting design and has already exceeded the tensile strength of the material. Therefore, this paper suggests that the structure should be reexamined the cumulative effect of variable stiffness construction and the characteristics of shrinkage and creep of new and old concrete during reinforcement and design.关键词
加固改造/新旧混凝土/收缩徐变/应力重分布/实测研究Key words
reinforcing reform/new and old concrete/shrinkage and creep/stress redistribution/the measured research分类
建筑与水利引用本文复制引用
卫军,黄敦文,李松林,陈聪聪,陈涛..既有结构改造加固的应力重分布研究[J].铁道科学与工程学报,2018,15(5):1255-1261,7.基金项目
国家自然科学基金面上资助项目(51378501,51578547) （51378501,51578547）
