Shaking Table Test On The Structural Model Of A Large Ship Lift Tower

This thesis presents the shaking table test results of a 1/25 scaled structural model of a large ship lift tower, a large triumphal arch type twin-tower skyscraper. Based on the measured dynamic responses of the structural model, seismic performance of the structure was evaluated. Furthermore, linear time-history analysis of the structural model was carried out by using program SAP2000.Both the test results and analytical results reveal that the dynamic response of the model under one-way excitation is the governing component. Its dynamic response under multi-way excitation can be predicted based on its one-way excitation results because the tower structure is symmetric. The peak acceleration envelopes of the model along the model height are S-shaped with the smallest peak acceleration near the 10th floor level. This characteristic does not change with different earthquake records or different base excitation methods. The variation of the acceleration amplification factor along the model height becomes uniform with base peak acceleration increased. The dynamic response of the tower does not change obviously when the ship-chamber model was in different positions, however, the maximum coupling forces between the ship-chamber and the tower changed significantly for the ship-chamber model in different positions. Based on the experimental results, it can be concluded that the designed ship lift tower is safe under the design earthquake level and has sufficient safe margin.Due to few holes on the longtitudinal surface of the ship lift tower and few floors in the ship lift tower along its height, placing additional mass on the available floors is difficult. In order to solve this problem, adding or eliminating the floor plates at some local levels and leaving temporary opens on the longtitudinal surfaces of the tower model were adopted. SAP2000 software was used to predict the possible effects of the former variations. The predict results demonstrate that the propoded method is feasible. However, the temporary opens on the longtitudinal surfaces must be carefully piece up.Finally,some discussions on the similitude laws adopted in shaking table test in China’s mainland during the last decades were summarized. Pushover analysis and nonlinear dynamical analysis of different structural models of a 6-story frame structure were carried out by using software SAP2000 and MSC.MARC respectively. Variables considered are column reinforcement ratios and lack artificial mass degree. It was found that the effect of the lack artificial mass degree is significant for the model with smaller column reinforcement ratio and will be acceptable for the model with larger column reinforcement ratios. If the mechanical parameters of the model reinforcement is close to those of the prototype reinforcement but the Young’s modulas ratio of the theoretical concrete model is 0.3 for a scaled 6-story frame structural model with lack additional mass, the seismic resisting capacity of the prototype structure will be overestimated based on the results of the scaled model. However, if the structural elements are designed based on similitude capacity principle, the predicted seismic behavior of the prototype structure will be more reliable.