Evaluation Of Bending Elastic Modulus Of Field Cement Concrete Surface Based On Shear Wave Velocity Variation

With the rapid development of civil aviation,the number of aircraft and airport flight volume also experience a rapid increase,the airport concrete pavement damage is not rare due to the lack of capacity,In order to avoid the occurrence of this phenomenon,concrete pavement strength detection needs to be conducted regularly.As a key index in the evaluation of concrete resistance,the concrete flexural modulus is needed.The traditional destructive core-drilling test will damage the road surface while non-destructive testing methods like FWD have disadvantages like clumsy equipment and high detection costs.These two methods cannot be widely used in field test.The shear wave can only propagate in the solid medium.In the process of transmission,it can carry on the physical and mechanical properties of the media,and access to a simple and convenient way.The physical and mechanical properties of the airport pavement are evaluated by establishing the relationship model between the shear wave velocity and the mechanical parameters of the concrete pavement surface-the bending elastic modulus.Based on the thin plate theory of small deflection,the theoretical model regarding the relationship between shear wave velocity and flexural modulus in cement concrete pave plates is proposed.The three point flexural tests of concrete beams with different grades are simulated to obtain the elastic modulus and corresponding flexural stress-strain curve based on the plastic damage model of concrete in ABAQUS.On this basis,the mathematical model between shear wave velocity and elastic wave theory is established.Experimentally,the propagation of Rayleigh wave after the standard curing age was tested by making the cement concrete standard specimens with different grades.The shear wave velocity values were converted into the shear wave velocity values.Finally elastic modulus values are obtained from experiments to contrast the effectiveness of theoretical model and finite element mathematical model.The comparison between the theoretical model and the finite element model with respect to actual experimental data shows that the relative error of the finite element model is about 8.13%,which is closer to the actual situation.Thus the feasibility of applying the finite element simulation of the shear wave velocity to evaluate the flexural elastic modulus is verified.This paper furthermore provides the relevant basis and theoretical guidance for the non-destructive testing of concrete pavement by shear wave velocity in practical engineering application.