Safety Evaluation Of Engineering Structures Based On Dynamic Characteristics

Firstly this paper uses the finite element analysis software ANSYS, establishing aseparate finite element model of reinforced concrete simply supported beam, includingfinite element, concrete crack, the elastic modulus of concrete local drop model,calculating the vibration characteristic parameters of various beam, containing crackdepth, location changing dynamic characteristics of reinforced concrete simplysupported beam, and different elastic modulus of simply supported reinforced concretebeams.On reinforced concrete beam vibration modal testing, this paper adopts the methodof single point excitation, including simply supported beam dynamic characteristics ingood condition and dynamic characteristics in different crack depth situations, to findout the relationship between the result of actual damage mode and damage parameters,its variation rules of damage under the condition of dynamic characteristics changingwere verified.Numerical simulation of the measured results and separated model results arebasically the same, and they prove the correctness and reliability. They both show thatwith the increase of the degree of different injury, dynamic characteristics(naturalfrequency) reduce accordingly, and with the modal number increasing, self vibrationfrequency decreases more, in different damage locations and under the condition ofstructural members span damage, the frequency of across damage vibration value islower than other positions, which reveals that structural dynamic characteristics inacross damage is obvious, although it is indirectly proves it is feasibility that the thoughtidentifying structural damage by dynamic characteristics changes.