（1 同济大学预应力研究所， 上海 200092；2 同济大学先进土木工程材料教育部重点实验室， 上海 200092）

［摘要］通过研究无粘结预应力混凝土结构极限应力增量与结构整体变形的关系，提出了一种基于挠度和支座转角的无粘结预应力筋极限应力应力增量的计算方法；并通过理论推导建立了预应力筋极限应力增量与跨中挠度和支座转角的公式，进而利用该计算公式统一了连续梁和简支梁在不同荷载条件和约束分布下的计算。对比了国内外142根试验梁（包括简支梁和连续梁）极限应力增量的试验结果和各计算方法计算所得的结果，结果表明，本文计算方法计算得到的结果与试验结果的吻合程度较高，这说明本文计算方法具有较为广泛的适用性。

［关键词］无粘结筋； 极限应力增量； 跨中挠度； 支座转角

中图分类号：TU378-1文献标识码：A文章编号：1002-848X(2018)08-0024-05

Research on  ultimate stress increment of  unbonded tendon in partially prestressed concrete beam base on overall structure deformation

Xiong Xueyu1,2, Wu Tao1

(1 Institute of Prestressed Structures, Tongji University, Shanghai 200092, China;  2 Key Laboratory of Advanced Civil Engineering Materials(Tongji University), Ministry of Education, Shanghai 200092, China)

Abstract:Based on the study of the relationship between the ultimate stress increment of unbonded prestressed concrete structures and the overall structural deformation, a method to calculate the stress increment of ultimate stress of unbonded prestressed tendons based on deflection and bearing rotation angle was proposed. The formula of ultimate stress increment, mid-span deflection and bearing rotation angle of prestressing tendons were deduced theoretically. Then, the calculation formulas of continuous beam and simply supported beam under different loading conditions and constraint distributions were unified. The experimental results of the ultimate stress increment of 142 test beams (including simply supported beams and continuous beams) at home and abroad were compared with those calculated by some calculation methods. The results show that the experimental results and calculation results calculated by the proposed calculation method agree well, which shows that the proposed calculation method is widely applicable.

Keywords:unbonded tendon; ultimate stress increment; mid-span deflection; bearing rotation angle

作者简介：熊学玉，博士，教授，博士生导师，Email: xueyu@ tongji.edu.cn。