Urban Seismic Resilience Evaluation Based On Christchurch Earthquake Damage Information And Detailed Simulation

Modern cities in the earthquake-prone areas tend to be more intricate and vulnerable due to the concentration of people and social wealth.The increasing risk due to natural hazards arise the need for new approaches to reasonably evaluate and strengthen the resilience of cities.High-performance computing and Geographic Information System provide a great chance to simulate earthquake disaster in a city level.The 2011 Christchurch earthquake induced a painful but typical disaster that a modern city(Christchurch city)was severely damaged by strong ground motions.Although many studies have investigated the building performance in this earthquake and recovery process after it,it’s far from enough to achieve a reasonable understanding of the disaster.This thesis focuses on simulating the earthquake damage and recovery of the central business district(CBD)of Christchurch city and analyzing the seismic resilience of this area.The main works of this thesis are as follows:1.An extensive investigation on the building damage in the Christchurch CBD is conducted.The building information of this district,including structural information,performance of buildings and demolition distribution,is collected and summarized from online database,satellite maps and street views.The detailed damage of some buildings is collected according to the related papers which take these buildings as the study cases.Most of buildings in this district were reinforced concrete or reinforced masonry structures.Many of them suffered a damage level of moderate or severe.Due to the high repair costs,it is difficult to quickly restore the basic function of these buildings.2.The numerical simulation on the seismic damage of the buildings in the 2011 Christchurch earthquake is carried out.The simulator,called You Simulator,calculates based on the physics-based nonlinear model and modern scalable simulation techniques.The accuracy of the simulation is verified by comparing the simulation results with the damage data in investigation.3.The related recovery models of the earthquake damage recovery are reviewed.An investigation of recovery process is conducted on some buildings in this district,including demolition start date,demolition completion date,reconstruction start date and reconstruction completion date.A bilinear building recovery model is proposed to simulate the Christchurch CBD recovery process.And the parameters of the proposed model are determined according to recovery survey.Based on this recovery model,the simulation on recovery process of Christchurch CBD is conducted.4.The proposed seismic damage simulator and recovery model are applied to the simulation of Christchurch recovery.An incremental dynamic analysis of this district is conducted to simulate urban damage and recovery in earthquakes of different intensities.An urban seismic resilience evaluation method based on the integral value of the recovery curve is proposed.Finally,an evaluation of the urban seismic resilience is conducted for Christchurch.