Research On The Anti-seismic Assessment Of Arch Bridge Based On Modified Modal Cyclic Pushover Method

The arch bridge with its good crossing ability, beautiful appearance, economy applicablewidely used in bridge design, in today’s transport network and social economy, bridge playsan important role and key position, the research on its seismic performance is a verymeaningful work. Aiming at shortcomings of bridge seismic, the improved modal reciprocalpushover (MMCP) into the seismic analysis of arch bridge structure. This paper mainlycarries out the following research work:1A set of3common long span arch bridge pier (compared with concrete, steelreinforced concrete piers and ordinary reinforced concrete piers) finite element model, pierheight is1.9m, the steel reinforced concrete bridge piers and the reinforced concrete piersection size is300mm×300mm, steel tube concrete pier D diameter is300mm, the ratio ofreinforcement are2.7%. On3groups of pier respectively by OBG, SFS, SUN, SGS and TAR5seismic waves were analyzed by MMCP analysis method and dynamic time history analysis,through comparing the analysis results of the displacement, hysteretic energy dissipation anddamage index, it points out the differences between3groups in the seismic performance ofbridge piers under different materials, to verify the MMCP method not only in the reinforcedconcrete structure has applicability in concrete, steel and steel structure also has applicabilityand precision.2The three group of steel arch structure finite element model, arch ribs are using thesection diameter is165mm, the span of5.4m steel tube arch rib, piers, height, section size andreinforcement ratio and the same type bridge pier. The reinforced concrete rigid frame archusing projection method respectively, uniform distribution, triangular distribution andequivalent mode distribution of three kinds of horizontal load distributions applied to thestructure, MMCP analysis to it, obtains three kinds of lateral load distribution patterns in theseismic waves of different intensity (EPA) damage index structure, through comparative analysis different load distribution of bridge structure damage assessment effect.3Considering modal influence, on3groups of steel arch structure with lateral loaddistribution of inverted triangle, were OBG, SFS, TAR MMCP analysis and dynamic threeseismic time history analysis, through the analysis of the displacement, hysteresis of energyintensive, damage index and the hysteretic curve are compared three, the seismic performanceof steel arch in different materials under the pier, verify the applicability of the MMCPmethod in arch bridge structure.4The column pier and the steel arch structure dynamic time history analysis, are usedfor seismic wave ē site a region were analysed in the characteristic period, by the analysisof damage index damage index and the "MMCP design guidelines for seismic design ofhighway bridges" response spectrum are compared, the MMCP method the design of thebridge seismic response spectrum of standard arch bridge structure damage evaluation withsafety and economy of a certain.5The three group of steel arch and MMCP method and3groups of single bridge piercolumn dynamic time history analysis of structure damage index are compared, the steel archstructure due to the existence of arch rib, the seismic performance of single bridge pier andcolumn compared better, under the same intensity (EPA) under the action of earthquake, steelarch to small50%~80%than column single bridge pier damage index..