Research On Pounding Effect Of Continuous Rigid Frame Bridges And Approach Bridges Considering The Effect Of Abutment

Since the beginning of the 20 th century,my country has vigorously developed infrastructure construction.The infrastructure in my country’s main developed regions has been basically improved,but the western region is still relatively backward.In recent years,the country has gradually accelerated the pace of capital construction in the southwest and northwest regions.The western region is dominated by mountainous areas and frequent earthquake-prone areas.Therefore,the earthquake resistance of continuous rigid frame bridges with strong adaptability across mountain areas and canyons has become a focus of attention in recent years.Based on a continuous rigid frame bridge under construction in the west,this paper explores and considers the impact of the collision effect between the main approach bridge under the abutment on the structural response,and studies the impact of high-strength cushioning materials and hydraulic shock absorbers on the collision between bridge structures for such problems.Reduce the effect.The specific main research contents are as follows:(1)Establish a continuous rigid frame main approach bridge dynamic analysis model considering the abutment and establish four abutment forms,namely ignoring the impact at the abutment,considering the infinite stiffness of the abutment,and considering the interaction between the abutment and the backfill Action,consider the abutment-soil action and the abutment’s own strength.Then select the seismic wave and adjust the peak acceleration to 0.2～0.8g and increase in increments of 0.1g,and then input to perform incremental dynamic analysis of the structure.Study the differences in seismic response and collision effects between different abutment simulation methods with different levels of accuracy and detail.(2)Introduce the advantages and disadvantages of integral bridge abutments and seat abutments.Because of the many advantages of integral abutments,two analysis models of integral abutments and seat abutments were established to compare and analyze the impact of these two types of abutments on structural collision effects and seismic response.(3)Summarize the causes and influencing factors of collision,and further discuss the contact unit stiffness(20k N/m to 2×10^10k N/m)of the abutment bridge and the type of backfill behind the abutment(clay and sand)),the main approach bridge span ratio(0.3～0.6),the main bridge pier height ratio(0.5～1.0)and other parameters on the bridge structure collision effect and seismic response.(4)Aiming at the collision problem of the continuous rigid frame main approach bridge,study the damping effect of two high-strength cushions and hydraulic shock-absorbing devices on the collision effect of the bridge structure,and discuss the self-parameter setting of the two shock-absorbing materials(devices)The law of impact on bridge collision and seismic response.