碳纤维加固桥梁结构界面剪应力的试验研究

Experimental Study on Interface Shear Stress of Carbon Fiber Reinforced Bridge Structure

碳纤维作为一种结构加固的新型材料已经广泛应用于桥梁加固维修中,但采用预应力碳纤维加固的方式还不常见,而采用预应力碳纤维加固更能够充分发挥碳纤维高强轻质的特点。通过试验验证预应力碳纤维加固钢筋混凝土梁界面层剪应力的理论计算公式,分析预应力作用下碳纤维和混凝土之间的界面层剪应力分布。采用密贴法对释放外力后碳纤维应变进行测量,试验证明试验值与理论值相吻合,并根据理论值和试验值讨论初始预应力、碳纤维厚度和界面层厚度对界面剪应力的影响。

As a new material for structure reinforcement,carbon fiber has been extensively applied in reinforcement repair of bridges,but reinforcement by pre-stressed carbon fiber is not common yet,which however can give full play to the feature of high strength and light quality of carbon fiber.This paper verifies the theoretical formulae for shear stress of interface layer of reinforced concrete bridges reinforced by prestressed carbon fiber,and analyzes distribution of shear stress in interface layer between carbon fiber and concrete under prestress.The paper adopts close contact method to measure the strain of carbon fiber after releasing external force,and the test proves that the tested value is identical with theoretical value,and based on which the influences of initial prestress,thickness of carbon fiber and thickness of interface layer on interface shear force.