摘要
试验研究了盐冻环境下钢筋混凝土梁抗弯性能的退化规律,分析比较了完好梁和经历25、50、75及100次盐冻融循环作用梁的承载力和变形性能。结果表明:受冻梁截面混凝土应变仍满足平截面假定,受力特征与完好梁相似;影响盐冻融环境下梁承载力的主要因素是受压区混凝土保护层的剥落,其次是混凝土强度的降低,而钢筋与混凝土粘结性能退化的影响并不显著;混凝土强度降低、保护层损伤及粘结性能退化均是冻融环境下混凝土梁变形增大的重要因素,梁刚度的降低程度除与冻融次数相关外,还受冻融损伤位置和持荷水平影响。
Under the salt frost environment, the flexural behavior of reinforced concrete was studied. The bearing capacity and deformation performance of the beams were analyzed by comparing with the reference beam（undamaged） and beams subjected to 25,50, 75 and 100 salt freeze-thaw cycles respectively. The results showed the plane section hypothesis still was satisfied for the concrete strains of frost beam section, and the mechanical characteristics of frost beam was similar to reference; The main reason to affect the beam bearing capacity under salt freeze-thaw environment was the concrete cover scaling in the compressive zone. Secondly, it was the reduction in concrete strength, while the degradation of bond properties between rebar and concrete was not a dominated factor; the deformations of concrete beam increased mainly due to the reduction in concrete strength, the damage of concrete cover and the degradation of bond properties. In addition to the number of freeze-thaw cycles, the positions of freeze-thaw damage and the load level affected the degree of reduction in beam stiffness.
出处
《土木建筑与环境工程》
CSCD
北大核心
2014年第3期86-91,共6页
Journal of Civil,Architectural & Environment Engineering
基金
国家自然科学基金(51379111
51109121)
湖北省自然科学基金计划创新群体项目(2010CDA076)
高速铁路建造技术国家工程实验室开放基金资助项目
关键词
钢筋混凝土梁
盐冻
耐久性
抗弯性能
reinforced concrete beam
salt-frost
durability
flexural performance
