Shaking Table Experimental Study On Main Bridge Of Puwan Sixteen Bridge

The sixteen cross-sea bridge is an important traffic line connecting north and south banks. The main bridge is designed as five-span tired handle basket arch bridge with spread wings. The bridge not only needs to be analyzed theoretically, but also shaking table model test research, because of large span, complicated shape of the structure and complexity of stress.According to dynamic similarity theory, an experimental model with1:50ratios is made out of raw material of polymethyl methacrylate-acrylic in this paper. In order to make a research of the vertical and horizontal vibration character of the bridge, a simulation seismic shaking table test under vertical and horizontal seismic motivation is carried out.The dynamic character of the whole bridge have been gained by the experiment including acceleration, strain and displacement and force bearing and so on.Due to the limitation frequency range of the shaking table test, shaking table model test couldn’t base on similarity theory completely. Thus, setting up the theoretical calculation model by the large finite analysis software-Midas/Civil to make the analysis of dynamic character, and make the dynamic response analysis by choosing the actually measured acceleration data of the bottom bearing of the shaking table. With the comparison of the theoretical value and the measured value, the validity of calculation model of the bridge and dynamic analysis has been validated. Based on the analysis, certain modifications have been made with the calculation model and actually measured acceleration and dynamic character and response meeting the regular similarity theory has been gained.Taking the response of the structure under artificial seismic wave1and2, the influence of different damping ratio of structure on shear force, acceleration, stress and displacement has been researched. The results show that the damping ratio has great influence on various parameters of the structure when the damping ratio is less than0.03.The influence cannot be ignored. When the damping ratio is greater than0.03, the influence of damping ratio on the structure is very small. The influence can be almost ignored.Taking a small scale model as the research object in this paper, by the comparison of the shaking table model test and theoretical model, The reliability of the shaking table test and the correctness of the calculation theory has been validated. The results provides a reference for elastic-plastic time history analysis of the bridge at the same time.