碳纤维加固预应力混凝土梁效率折减研究

碳纤维复合材料具有轻质、高强和耐腐蚀等特性,加固结构时对原结构外观改变小,所需费用不高,效果较佳.在加固预应力混凝土梁时,由于碳纤维片材的应变很小,设计容许应变值只有0.01左右,这样造成预应力钢筋的应变也被限制,预应力筋的高强度由于应变的限制而不能发挥.同时高强预应力钢筋没有明显的屈服点,使名义屈服点以后的强度储备未能利用前,便因FRP片材拉断而破坏,从而降低了加固效率.

Research on Efficiency of Discount for Carbon Fiber Reinforced Prestressed Concrete Beams

CFRP materials possess characteristic of light-weight, high strength and resistance to corrosion and other features. The changes to the appearance of the original structure is small when reinforcing with CFRP materials, what＇s more, the cost is low and the effective is excellent. But the strain of this material is small. It has been limited only 0.01 for design to strengthen PC bridges, so prestressing tendons strain is also restricted. High-strength of prestressing tendons due to the restriction of strain can not play. At the same time, high strength prestressing tendons has no obviously yield point. Actually it makes the nominal yield point strength reserve beyond the failure to use effectively, the CFRP sheets will be pulled off, and the damage reduces the efficiency of reinforcement.