疲劳荷载下锈蚀部分预应力混凝土梁挠度试验研究  

Experimental Study on Deflection of Corroded Partial Prestressed Concrete Beams Under Fatigue Loads

作　　者：窦远明[1] 杨雨兮 李岩峰[1] 张硕[1] 刁硕[1] 

机构地区：[1]河北工业大学土木与交通学院,天津300401

出　　处：《施工技术》2017年第9期35-38,70,共5页Construction Technology

基　　金：河北省交通运输厅科技计划项目(Y-2012046)

摘　　要：通过对6根不同锈蚀率的部分预应力混凝土梁进行静力和疲劳试验,研究了疲劳荷载下锈蚀部分预应力混凝土梁破坏形态、疲劳寿命、刚度及跨中挠度的变化规律。试验结果表明:疲劳荷载作用下,锈蚀部分预应力混凝土梁均发生以某一主筋脆性断裂为标志的正截面弯曲疲劳破坏,随着钢筋锈蚀率的增大,锈蚀试验梁的疲劳寿命显著降低。锈蚀试验梁在疲劳荷载作用下的刚度变化呈现出3个阶段:迅速下降→缓慢下降→趋于平稳。根据锈蚀梁跨中挠度的变化规律,提出了疲劳荷载下锈蚀部分预应力混凝土梁跨中挠度的计算公式,其结果与试验数据吻合程度良好。The failure modes, fatigue life and the development of stiffness and mid-span deflection of corroded partial prestressed concrete beams under fatigue loads were studied from the static and fatigue tests of six partial prestressed concrete beams with different corrosion rates. Experimental results show that the normal section flexural fatigue failure of corroded partial prestressed concrete beams was indicated by the fatigue rupture of one main bar occured in it, and the fatigue life of corroded beams significantly decreases with the corrosion levels of reinforced bars increasing. The stiffness of corroded beams under fatigue loads performs three distinctive stages, declining quickly, and slowing down-tending to be stable. The calculation formula of mid-span deflection of corroded partial prestressed concrete beams under fatigue loads was developed on the basis of analysis of mid-span deflection characteristics of corroded beams, whose results are in agreement with the experimental data.

关 键 词：混凝土 预应力 梁 疲劳加载 刚度 挠度 试验研究 

分 类 号：TU378.2[建筑科学—结构工程]