Research On The Anti-seismic Assessment Method Of The Continuous Rigid Frame Bridge Which Considering The Strong Aftershocks Influence

As the most critical role in the bridge family, the anti-seismic capability of thecontinuous rigid frame bridge proves to be very hot in the research of the bridgeanti-earthquake. In view of the shortage of the present seismic performanceassessment method in continuous rigid frame bridge and taking the energy anddisplacement method and the influence of strong aftershock into consideration, thispaper puts forward the double index assessment method of seismic performanceassessment method in continuous rigid frame bridge under the action of the strongaftershock. The main work we will do include the following aspects:(1)According to the magnitude relationship between the main shock andaftershock and the statistical formula of peak acceleration, duration and site soilcharacteristics epicenter, magnitude and the regression coefficient, the compositemethod of main shock-aftershock will be explored, Moreover, using mainshock-aftershock wave and strong aftershock wave to combine the equivalentseismic waves that grounded on the energy equivalence principle and therelationship among spectral intensity factor and magnitude, epicentral distance andduration.(2)Three typical sets seismic waves will be adopted to do the time historyanalysis of the single degree of freedom structure, and we will study the influencerules of the peak acceleration, duration and spectrum characteristics on the singledegree of freedom structure seismic response of the piers and analyze the influencerules of the main shock-aftershock on the hysteretic energy, damping energy and thetotal input energy of the single degree of freedom structure.(3)The finite element model of certain continuous rigid frame bridge will beconstructed and we are aim at simplifying it to the multi-freedom structure to do theseismic time history analysis. The energy response's computing method of thecontinuous rigid frame bridge is also came up with and the bridge's design parameteris analyzed, such as: how the pier's height, reinforcement ratio influenced theanti-seismic capability of the continuous rigid frame bridge, in the meanwhile, theinfluence rules of the main shock-aftershock to the seismic internal force,displacement and energy response in the continuous rigid frame bridge are revealed.( 4 ) Analyzing the time history through a large number of main shock–aftershock waves and equivalent waves, the statistical relation between incrementfactor and magnitude are obtained through using the Park-Ang damage index tocalculate the damage index and introducing the displacement and hysteretic energydissipation incremental factor. Considering the deformation of the strongaftershock's influence, we have putted forward the energy double parameters seismicdamage model and verified the reliability of this model by means of the calculations.