| The Bus Rapid Transit System(BRT),has become an important development part in public transport system because of the speed, comfort, convenience, large passenger loads and cost-effective, especially in major cities of China in recent years. Private bridges is a significant part of BRT system. Bridges built in earthquake-prone area not only need to meet the seismic design,but also can be used as emergency rilief and life resue accesses after rapid detection and maintenance after earthquake.Based on seismic analysis of BRT bridges in Xiamen for rapid detection and evaluation,an index system is established in this paper,which especially apply to Xiamen city BRT bridge system. The main work is as follows:1. Through reading references domesitc and overseas in bridge seismic field,the current mainstream seismic analysis methods and theories are summarized as the theoretical basis of the seismic analysis in this paper.2. According to the differences of the construction materials, structural system, bridge span arrangement, alignment and substructure style among Xiamen BRT bridges, 6 sepcial bridges are selected as the analysis object.3. According to the theoretical foundation of the dynamic characteristics of the bridge structure, the selected types of bridges were analyzed respectively to obtain the natural vibration characteristics of various types of bridges.4. Through response spectrum analysis aiming at various selected bridges,internal force and displacement of the key section,force characteristics and the most disadvantaged sections are obtained,which can provide theoretical support for rapid detection and evaluation index system after earthquakes.5. Considering the relevant norms and result of seimic analysis,weight coefficient in index system is adjusted for each part though setting threshold about the seismic action to bridge structure damage.This paper establish an index system which especially apply to Xiamen city BRT bridge system though ranking the danger level about various bridge and related section under seismicity. |
