摘要
为探讨腐蚀对钢绞线与混凝土长期粘结蠕变性能的影响,制作6根先张法预应力混凝土梁试件,其中5根试件通过掺盐并置于不同环境中进行为期47周不同强度的长期腐蚀,期间对所有6根试件进行定期粘结滑移监测,得到各试件在预应力作用下的粘结滑移时变曲线。结果表明:在未发生锈胀开裂的条件下,腐蚀引起粘结强度增大,从而抑制了粘结蠕变,使腐蚀试件的蠕变滑移小于无腐蚀试件;而且,腐蚀率越高、腐蚀产物体积膨胀率越大,长期粘结滑移也越小。分析表明:如果腐蚀引起锈胀开裂并导致粘结强度退化,则会引起长期粘结蠕变及锚固段裂缝宽度的增大,但不会引起预应力损失及锚固承载力的降低。
To study the influence of steel strands corrosion on the long-term behavior of bond-creep, 6 pre-tensioned prestressed concrete beams were fabricated, of which, 5 beams were mixed with salt and set in different places to be corroded in different intensity for 47 weeks, and the bond-slip of all the 6 beams was tested periodically through the whole period, and then the time varying curves of bond-slip under prestressing were obtained. The results show that under the condition of no corrosion crack, the bond strength increases with corrosion and the bond-creep is restrained, which contribute the creep slip of corrosion beams being less than that of the uncorrosion beam. Moreover, with the increase of corrosion rate and corrosion products expansion ratio, the long-term bond-slip decreases. The analysis shows that if there are corrosion cracks and the bond strength deteriorates, the long-term bond-creep and the load cracks width in anchoring segments should increase, but the prestressing loss and the anchoring bearing capacity should not decrease.
出处
《工业建筑》
CSCD
北大核心
2012年第2期70-73,18,共5页
Industrial Construction
基金
国家自然科学基金资助项目(51178454)
华南理工大学亚热带建筑科学国家重点实验室开放基金项目(2010KB03)
关键词
预应力混凝土结构
耐久性
钢绞线腐蚀
粘结
蠕变
prestressed concrete structures
durability
corrosion of steel strand
bond
creep
