Effect Of Ground Transportation Incentive On Ancient Architecture And Damage Identification Study Of Ancient Wood Structure

Because of environmental erosion, material aging and long-term effect of load and fatigue effect, ancient architecture appeared the damage accumulation and resistance attenuation in hundreds or even thousands of years. It is seeing increases in traffic flow with the rapid development of urban economy, it has an important influence on the safety of ancient architecture, thus it is necessary to evaluate the effect of transportation incentive on ancient architecture and to carry on health monitoring and safety assessment on ancient architecture by the data of structure vibration response under environment incentive. Xi’an bell tower and Xi’an city wall are national cultural relic’s protection units. The paper did numerical analysis on the effect of Xi’an bell tower and Xi’an city wall under the micro vibration of ground transport vehicles and the safety assessment. The paper researched the damage identification indexes of ancient wood structure under environment excitation based on wavelet packet energy spectrum. The research results were applied on the damage identification of Xi’an Bell tower. The main contents include:(1) Taking Xi’an bell tower and Xi’an city wall as the research objects, the paper established the finite element model of wood frame-tower base-cylindrical foundation of Xi’an bell tower and city wall-foundation, and studied the safety assessment and influence of Xi’an bell tower and Xi’an city wall under the micro vibration of ground transport vehicles.(2) The paper did the finite element simulation of ancient wood structure under random excitation, and established the damage indexes of ancient wood structure based on wavelet packet energy spectrum. The process comprised the selections of wavelet functions and wavelet packet decomposition level and the analysis of the damage sensitivity and noise effect.(3) The paper decomposed the acceleration response on beam node of ancient wood structure under random excitation based on wavelet packet, and put forward to the damage index—wavelet packet energy curvature difference to locate the damage of ancient wood structure. The relation of damage index and damage degree was established to assess the damage degree of ancient wood structure, and its applicability was checked.(4) Taking Xi’an bell tower as a research object, the finite element of wood structure was done to research the damage identification. The paper studied the damage identification on Xi’an bell tower under micro vibration of ground transport vehicles, and established the damage indexes of Xi’an bell tower based on wavelet packet energy spectrum. The process comprised the selections of wavelet functions and wavelet packet decomposition level and the analysis of the damage sensitivity and noise effect.(5) Taking Xi’an bell tower as a research object, the paper studied the damage identification of Xi’an bell tower under micro vibration of ground transport vehicles, and put forward to the damage index—wavelet packet energy curvature difference to locate the wood frame damage of Xi’an bell tower, and analyzed the damage sensitivity and noise effect. The relation of damage index and damage degree was established to assess the damage degree of wood frame on Xi’an bell tower.(6) The paper decomposed the test acceleration response of Xi’an bell tower under micro vibration of ground transport vehicles based on wavelet packet energy spectrum, and discussed the damage identification indexes of Xi’an bell tower based on the measured wavelet packet energy spectrum—energy ratio deviation ERVD and energy ratio variance ERVV. They could characterize the vibration effect of ground traffic incentive on Xi’an bell tower, so they are suitable for the real-time damage identification of Xi’an bell tower under environment excitation.