预应力CFRP布加固负载混凝土柱轴心受压性能研究

摘要

In order to study the mechanical properties of preloaded circular short concrete columns strengthened with prestressed carbon fiber reinforced polymer (CFRP) sheets under axial compression, 11 circular short concrete columns were designed, including an ordinary concrete column served as reference column and 10 columns strengthened with prestressed and non-prestressed CFRP sheets at preloaded and non-preloaded states, respectively.The ultimate loads, axial deformations and stress variations of materials were obtained by the axial load test.The mechanical properties of the test columns under axial compression were analyzed based on the test data.The results show that the yield loads of the preloaded concrete columns strengthened with prestressed CFRP sheets compared with the ordinary column are significantly improved in the second load, and the increased range is proportional to the prestress level of CFRP sheets.However, the ultimate bearing capacities of the test columns have no obvious relationship with the prestress level of CFRP sheets.The ductility of the preloaded concrete columns strengthened with prestressed CFRP sheets is improved significantly.%为开展轴心压力作用下预应力碳纤维增强复合材料(CFRP)布加固负载圆形截面混凝土短柱力学性能研究,设计制作了11根圆形截面混凝土短柱,其中1根普通混凝土柱为对比柱,其余10根混凝土柱在负载与非负载2种情况下分别利用预应力CFRP布或非预应力CFRP布进行加固.通过轴心加载试验,获得了各试件极限荷载、轴向变形、材料应力变化等试验数据.基于试验数据分析了试件轴心压力作用下的力学性能.结果表明:与普通混凝土柱相比,利用预应力CFRP布加固的负载混凝土柱在二次受力过程中其屈服荷载有显著提高,且提高幅度与CFRP布预应力水平成正比,但极限承载力与CFRP布的预应力水平无关;利用预应力CFRP布加固的负载混凝土柱延性性能有显著提高.