Technique Research And Construction Management Of The Additional Steel Beam On Solo Column Pire For Anti-overturning Capacity Rehabilitation

Single column pier has the advantages of beautiful shape,simple structure,economy and strong adaptability to terrain and ground features.It is a pier form widely used in overpass,viaduct and Viaduct of urban roads in China.With the substantial increase of traffic volume and the increasing traffic density and vehicle load,the single column pier bridge may pay more attention to the bearing capacity of the structure and ignore the impact of eccentric overload on the bridge safety in the design,resulting in insufficient transverse anti overturning capacity of the bridge and reaching the service life in advance.The addition of anti overturning steel joist is widely used in the reinforcement of all kinds of single column concrete piers because of its small construction volume,good landscape and light structure.Although steel joists have been widely used in pier anti overturning reinforcement,most reinforcement projects are designed and constructed based on engineering experience,there is no relevant design code and theoretical basis,and the shear failure mechanism of steel joist interface has not been fully revealed.Therefore,through finite element simulation calculation and experimental research,this paper will deeply study the bearing capacity of steel joists and the shear performance of steel hoop interface bolts of steel joists,and put forward the construction technical guidance of steel joists.The main work is as follows:Combined with practical engineering examples,this paper uses ABAQUS software to simulate the full-scale steel joist model,and studies the stress distribution of each part of the structure under the most unfavorable load and ultimate bearing capacity.The calculation results show that under the most unfavorable load,the steel joist structure still has a certain safety surplus,which can effectively strengthen the single column concrete pier.In this paper,the shear performance of steel hoop interface bolts of steel joists is studied by push out test.The test parameters include the number of bolts and the treatment method of steel-concrete interface.The test results show that the shear resistance of steel-concrete composite structure can be greatly improved by filling epoxy resin or grouting material at the steel-concrete interface,but the failure mode of the interface treatment method filled with epoxy resin belongs to brittle failure,which is not conducive to engineering application.In addition,comparing the specimens with different number of bolts,it can be clearly seen that the group nail effect has an impact on the shear performance of bolt shear connectors.The finite element software is used to simulate and calculate the specimen model,and the finite element simulation results are verified with the test results.After verification,thefinite element model established in this paper is consistent with the test model,and the research parameters that cannot be carried out in the test can be studied by this model.This paper studies the construction management of anti overturning reinforcement of single column pier.Combined with the actual operation on site,this paper puts forward the special construction scheme of adding anti overturning steel joist reinforcement for single column pier,which can effectively strengthen the single column pier,which can provide construction reference for the future single column pier reinforcement project,and has certain theoretical and practical guiding value.