In order to discuss the sensibility of influence line on the damage, a two-span continuous beam model is set up using the finite element method in the paper. The two damage positions at the middle span and 1/4 span are considered. And different damage degrees are simulated by the different crack depths. The shearing force and moment at four key positions of the beam are calculated under the moving unit load separately. Results show that the moment influence line at the middle support of the beam is very sensitive to the beam damage, while the moment influence line at other positions and the shearing force influence line at each position are insensitive. In the moment influence line of the beam middle support position, the obvious different values appear at the middle span when damage in the middle span. As damage in the 1/4 span, the obvious different also appear at the damage position, and the difference is increased unconspicuous up to the middle span, and then decreased soon. The conclusion is beneficial to determine the position of damage by means of comparing the moment influence line with that of undamaged bridge. Moreover, the difference value of moment influence line can also be used to estimate the damage degree.
STUDENČICA BRIDGE TESTING
