(1 河北工业大学土木工程学院，  天津 300401； 2 河北省土木工程技术研究中心， 天津 300401)

［摘要］为了得到重载交通对预应力混凝土梁的疲劳性能影响，对9根预应力混凝土模型梁分别进行静载试验和等幅疲劳试验研究。研究结果表明，部分试验梁在经历过200万次疲劳荷载作用后，其静力极限强度不但没有大幅度降低，反而略有提高；在重载作用下的疲劳破坏均始于非预应力钢筋的疲劳断裂；试验过程中疲劳损伤明显呈三阶段发展规律，当疲劳荷载上限达到0-7倍的极限荷载时，疲劳寿命大于200万次，当疲劳荷载上限达到0-75倍极限荷载时，疲劳寿命仅为10-2万次，当疲劳荷载上限达到0-85倍的极限荷载时，预应力混凝土梁的疲劳寿命仅为5-1万次；得到了预应力混凝土梁的容许疲劳寿命方程。

［关键词］重载交通； 疲劳寿命； 等幅疲劳试验； 预应力混凝土梁； 疲劳损伤

中图分类号：TU375文献标识码：A文章编号：1002-848X(2017)06-0055-05

Study of heavy load traffic effect on fatigue performance of pre-stressed concrete beams

Zhao Chuan1,2, Dou Yuanming1,2, Sun Jishu1,2, Li Yanfeng1,2

(1 College of Civil Engineering, Hebei University of Technology, Tianjin 300401, China;

2 Civil Engineering Technology Research Center of Hebei Province, Tianjin 300401,China)

Abstract:In order to get the impact of heavy load traffic on fatigue performance of pre-stressed concrete beams, static load tests and constant amplitude fatigue experiments were conducted on 9 pre-stressed concrete beam models respectively. The results show that static ultimate strength of part of the experimental beams not only fails to reduce significantly but slightly increases after experiencing 2 million times of fatigue load actions. The fatigue damage under heavy load starts from fatigue fracture of non-pre-stressed reinforcement. The fatigue damage during the test shows three-stage development rule clearly. When the upper limit of fatigue load reaches the 0-7 times of the ultimate load, the fatigue life is over 2 million times. When the upper limit of fatigue load reaches the 0-75 times of the ultimate load, the fatigue life is only 102 000 times. When the upper limit of fatigue load reaches the 0-85 times of the ultimate load, the fatigue life is only 51 000 times. Then the allowed fatigue life equation of pre-stressed concrete beam was obtained.

Keywords:heavy load traffic; fatigue life; constant amplitude fatigue experiment; pre-stressed concrete beam; fatigue damage

*河北省交通厅资助项目（Y-2012046）。

作者简介：赵川，博士，Email: zcsunshine@yeah.net。