Yingxian Wooden Tower Finite Element Analysis

Yingxian wooden tower is not only the tallest but the oldest existing wooden tower in China and whether from construction, raw material or outward appearance, it obtains high art value and is worth to be studied and researched by modern people. However, the tower has suffered from natural and man-made damage, such as seism, corrosion, war or material ageing nearly thousand years. Therefore, the tower is faced to be repaired and it is important to take action to carry out security evaluation, appraisal, protect and maintain. Though the method of experiment has achieved basic data, it does require numerical simulation technique to make advance deeply research. Using FEM theory is not only able to reduce the destruction caused by the experiment, but also extremely decrease the consuming of labor power and resources. What is the more, simulation is also able to complete tests, which the experiment can not do. In this paper, the damage types and mechanism of the tower has bean researched through theoretical analysis and numerical simulation method and the main content is:(1) Summarize the situation of yingxian wooden tower from material property, basic mechanism of the structure to damaging deformation based on the relative theory and research.(2) Establish the finite element model of the tower using MSC.Patran&Nastran software and discuss different finite element models for response seismic analysis and repairing simulation.(3) Summarize the research of the development of semi-rigid element and establish easy computing and analytic finite element model of mortise and tenon. In addition, parameters of the model have been obtained by comparing numerical result applied FEM software and consequence of crossing timber frame experiment, based on the response surface method and optimize interactive theory, and then obtain the result of statics analysis of the new model.(4) Dynamics analysis has been taken in this study and the inherent frequencies and vibration models of yingxian wooden tower have been obtained from numerical simulation, which are consistent well with the tested data. At the mean time, seismic response simulation shows the isolation and absorption of vibration ability of wooden tower and finds the position where easy to be broken.(5) Simulate damage situation using numerical method and provide property suggestion for the future repairing and maintaining of Yingxian wooden tower. Those numerical results could be applied on the intending structure inspection, seismic appraiser and enforcement of Yingxian timber tower and also will provide useful suggestion to other ancient wooden architecture research and modern building construction.