Research On The Seismic Performance Of A Type Of Assembled Self-resetting Pier With External Mild Steel Damper

Earthquakes have always been a serious threat to bridge projects such as highways and sea-crossing bridges in our country.Bridges are important channels for economic development,and bridge piers are the key to the seismic performance of bridges.In order to improve the energy dissipation capacity and repairable performance of the fabricated self-resetting pier.Based on the structural energy shock absorbing and seismic thinking.An external mild steel damper is attached to the fabricated self-resetting pier,forming an fabricated self-resetting pier combined with an external mild steel damper and built-in energy consumption steel bar,and verify the superiority of the pier.Specifically,the following studies:The type and performance of external energy dissipation dampers are studied.In contrast,low yield point mild steel energy dissipation dampers are selected as the external energy dissipation components of fabricated self-resetting pier.The traditional prefabricated self-resetting pier is established by numerical experiments.Compare the numerical simulation results with the reference test results of the traditional fabricated self-resetting piers.The results are basically consistent,which provide method support for subsequent research work.By comparing the simulation results of each model under low-cycle reciprocating loads,the seismic performance of the fabricated self-resetting pier with external mild steel dampers was studied.The results show that: compared with traditional fabricated selfresetting piers,the other seismic indicators of the fabricated self-resetting piers with external mild steel dampers are good.The residual displacement is increased,but the residual displacement angle is meet the limit of residual displacement angle less than 1%.Based on numerical experiments,the effect of mild steel damper yield strength parameters on the performance of fabricated self-resetting pier is studied.The results as follows: with the increase in the yield strength of the mild steel damper,the residual displacement of the external mild steel damper fabricated self-resetting pier is reduced.The energy consumption capacity is reduced when the loading displacement is less than25 mm,but the overall energy consumption capacity has improved.In terms of the bearing capacity and energy dissipation capacity of the pier,the best sharing ratio between the external mild steel dampers and the internal energy dissipation steel bars is 1.75.This research has certain reference significance for the design of prefabricated self-resetting bridge piers.Based on numerical experiments,the effect of the axial compression ratio parameters of pier columns on the seismic performance of prefabricated self-centering is studied.The results show that: with the increase of axial compression ratio,the bearing capacity and energy dissipation capacity significantly increased,but when the axial compression ratio more than 0.052,the effect is small.