The Loading Behavior Mechanism Of Reinforced Concrete Beams Strenghened By CFRP

This paper mainly focus on the mechanical behavior and properties of reinforced concrete beams which strengthened by CFRP (Carbon Fiber Reinforced Ploymer,referred to as CFRP) undering various kinds of loads.Using ANSYS,a kind of finite element simulation software to examine the results which are getted by experiments.Before experiments,we make a table of orthogonal experimental design according to pre-splitting degree,load velocity,load weight,strengthened ways by CFRP and so on,then produce a total of 12 test beams.Successively,we execute a serioue of static loading test,live loading test and vibration test.1. Static loading test,mainly explore the rule of cracking load,failure load and peak capacity among non-CFRP beams,non-loading history beams and beams of pre-splitting degree at some levels,then make some study about deflection and strain at several test points of beams undering loads;2. Live loading test,we do some theory analysis for mechanical performance of test beams, making some comparision on impact factor among these beams under several conditions using response formula for these beams under constant loading velaocity,and define a term named as impact factor response spectrum according to correlative curve among impact factor,strengthened ways and loads and get these test beams'graphs of impact factor response spectrum,then explore the influrence degree using CFRP to strengthen reinforced concrete beams.3. Vibration test,using existing structural dynamics knowledge to derive natural frequency and vibration mode function of these test beams,then comparing mode frequency and damp deriving from experiments with simulation value by ANSYS to determine working performance of CFRP for improving dynamic characteristics under actural circumstances,finally,concluding the influence ratio about different damping coefficient to strcuturals'natural vibration mode experimental results show that,work performancr of using CFRP sheet to strengthen reinforced concrete structures is quite excellent,especially those acturally structures which have been suffered some damages by all kinds loads;simultaneously,we find CFRP may make little harm to many inherent mechanical behavior indexes of these test beams,therefore,CFRP can be used as a promising new reinforced material.Finally,we summarize the conclusions in this paper and make some prospects for further study of this issue.