摘要
通过6根受腐蚀钢绞线部分预应力混凝土梁的弯曲疲劳试验,研究了疲劳荷载作用下梁的疲劳寿命及受腐蚀钢绞线的应变发展规律。试验结果表明:钢绞线腐蚀前,梁的疲劳损伤、钢绞线腐蚀率的增大以及最大荷载水平的提高均使梁的疲劳寿命显著降低;利用FBG传感器能够准确地测出梁内钢绞线的应变分布;梁内受腐蚀钢绞线的最大应变增量、残余应变均符合三阶段发展规律,并建立了各自与荷载循环次数之间的关系表达式。以上结果可以为疲劳荷载作用下,腐蚀钢绞线预应力混凝土桥梁的耐久性设计提供参考。
Tests were carried out for 6 partially prestressed concrete beams with corroded steel strands under fatigue loading. The fatigue lives of beams and the strain developing process of corroded steel strands were investigated. The results show that the fatigue lives of partially prestressed concrete beams are shortened considerably on the condition that the fatigue damage at an advanced stage of corrosion, the raising of the corrosion rate of steel strands and maximum load level. The FBG sensors are good at measuring strain distribution of steel strands in beams. The maximum strain increment and residual strain of the corroded steel strands accord with the law of the three stages development. The relational expressions between the maximum strain increment, residual strain and the number of cycle loading were established. The results may provide the reference for the durability design of prestressed concrete bridge with corroded steel strands under fatigue loading.
出处
《建筑结构》
CSCD
北大核心
2013年第21期69-73,共5页
Building Structure
基金
国家高技术研究发展计划项目(863计划)(2007AA11Z133)
辽宁省教育厅科技计划项目(2008T231)
关键词
预应力混凝土梁
钢绞线腐蚀
疲劳
FBG传感器
钢绞线应变
prestressed concrete beam
corroded of steel strand
fatigue
FBG sensor
strain of steel strand
