预应力CFRP板粘结H型钢梁加固系数及参数分析

THE ANALYSIS OF PARAMETRIC AND REINFORCEMENT COEFFICIENT ABOUT H-SECTION STEEL BEAMS REINFORCED BY PRESTRESSED CFRP PLATES

为研究各设计参数对预应力CFRP板加固H型钢梁刚度的影响,采用有限元软件ABAQUS对多组构件进行四点加载作用下的计算,分析CFRP板的长度变化、厚度变化、宽度变化、弹性模量变化以及预应力水平变化对加固性能的影响。在此基础上引入加固系数,结合简支梁跨中挠度计算公式给出适用于预应力CFRP板加固钢梁的计算公式,并将加固系数简化公式计算结果与有限元计算结果进行对比。研究结果表明:CFRP板的长度、宽度、厚度以及预应力大小对加固钢梁的刚度影响显著,CFRP板弹性模量对钢梁刚度的影响较小,且给出的加固系数简化公式具有一定的适用性和准确性。

Sticking carbon fiber reinforced composite material is a new reinforcement method. Compared with the traditional reinforcement material it has the characteristics of light weight and high strength. However the strength utilization ratio of strengthened by common CFRP is low. Therefore some scholars put forward the method reinforced by prestressed CFRP plates. In view of the present study no concrete formula for stiffness of composite beams after reinforcement is given. Therefore to study the effect of design parameters on H section steel beam stiff ness reinforced by prestressed CFRP plates the finite element software ABAQUS was used to calculate the multi components under four points loading. The influence of CFRP plate length thickness width modulus of elasticity and prestress level on the strengthening performance were analyzed. 0n this basis the reinforcement coefficient was introduced. Combining with the calculation formula of the mid span deformation on simple supported beam the cal culation formula for steel beam reinforced by prestressed CFRP plate was given. Afterwards the calculation results of simplified calculation formula of reinforcement coefficient were compared with the results calculated by ABAQUS. The results show that length width thickness and prestress size of the CFRP plate have a significant influence on stiffness of reinforced steel beam. Meanwhile the elastic modulus of CFRP plate has little effect on the stiffness of steel beam and the simplified formula of strengthening coefficient has certain applicability and accuracy.