摘要
为了揭示主动约束混凝土圆柱的损伤演化规律,在细观层次上分析了环向预应力主动约束混凝土的破坏机理,在构件层次上基于试验研究了环向预应力纤维条带主动约束混凝土圆柱的损伤演化规律,探讨了主动约束作用对混凝土圆柱刚度的影响,研究结果表明：随着应力水平的提高,损伤应变曲线的斜率先减小后增大,体现了柱的损伤发展由缓慢到快速的渐变过程;直至试件应变达到峰值应变,损伤度达到0.4-0.6之间时试件破坏;并在试验研究和理论分析的基础上,提出了损伤演化方程,该方程反映了预应力大小和混凝土强度等级对轴压混凝土圆柱损伤演化的影响;给出了适用于环向预应力纤维条带主动约束混凝土圆柱的等效初始弹性模量的计算公式。
To reveal the damage evolution of actively confined circular concrete columns, the damage mechanism of actively confined concrete with lateral prestress was analyzed at mesoscopic level, the damage evolution law of actively confined circular concrete columns was studied at component level, and the impact of active confinement on the cylindrical stiffness was explored. The results show that the slope of damage strain curve decreased first and then increased along with increase of stress. It indicates the gradual process of damage evolution from slow growth to rapid development. As the damage degree reaches between 0. 4 and 0. 6, strain of specimens reaches the peak strain and then specimens damaged. Based on test results and theoretical analysis, the damage evolution equation of circular concrete columns under axial compression is derived which reflects the influence of lateral pre-stress level and concrete strength grade on the damage evolution of circular concrete column. The equivalent initial elastic modulus of circular concrete columns actively confined with lateral prestressed FRP was proposed. 5 tabs, 8 figs, 16 refs.
出处
《长安大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2015年第5期65-72,共8页
Journal of Chang’an University(Natural Science Edition)
基金
国家自然科学基金面上项目(51478033
51178029)
关键词
结构工程
损伤演化规律
混凝土圆柱
环向预应力FRP
主动约束
structural engineering
damage evolution law
circular concrete column
lateral prestressed FRP
active confinement
