Quasi-static Test And Numerical Analysis Of Grouted Bellows Connected Assembly Piers

China's bridge assembly integration is just in its infancy.Due to the late introduction of technology,it is still in the initial exploration stage in terms of design theory and construction technology,and it refers to the successful technology of foreign countries.Up to now,prefabricated bridge substructures are still being built as a test on individual bridges in a non strong earthquake zone.The applicability,safety and seismic performance of precast and fabricated bridge substructure in the strong earthquake area are in the stage of technology development,and have not been widely applied in the strong earthquake area.The connection mode and seismic performance between the precast bridge substructure segments and the joints are the key and difficult problems of the present research.At present,the bridge substructure assembly connection is mostly connected by sleeve connection or prestressed series.In recent years,the fabricated metal pier connected by grouting metal bellows has gained the recognition of bridge builders quickly because of its low cost and convenient construction.Preliminary studies at home and abroad have preliminarily confirmed that the precast and assembled structural members based on grouted bellows connection have reliable connections and better seismic performance.The construction site assembly process is convenient and fast.But at home and abroad for grouting corrugated pipe connection technology research mostly confined to pier connection or connection of single pier,and the related research on corrugated pipe grouting prefabricated frame piers based on links are few.In order to make up for the deficiencies in this research,based on the previous research on the reference to Central Avenue in Shenyang city across Hunhe River Bridge,for the precast frame piers filling metal bellows model is constructed according to the scale of 1/4 produced two test specimens,through the low cyclic loading test in the laboratory to analyze the reliability and seismic performance the corrugated pipe grouting based on connected pier.From the experimental hysteresis curve can be seen:(1)the assembly type specimens and cast-in-place specimens demonstrated the phenomenon of basically the same,Reduction of peak bearing capacity of bellows prefab specimens by 6.7%as compared to the whole in-situ specimens;(2)By analyzing both of them,we can see that the yield load and the ultimate load error are not more than 10%· The yield displacement of the two of them is the same,but the ultimate displacement of the bellows connecting part is about 3%lower than that of the existing part,so the ductility coefficient of the assembly part is lower than that of the present part;(3)by comparing the residual displacement was found in two specimens with maximum residual displacement were about 55mm,but the filling of corrugated tube specimen residual displacement rate is greater than the cast-in-place specimen under the same hysteretic displacement under the cast-in-place specimen residual displacement is about 90%specimens of corrugated pipe grouting.(4)the energy dissipation capacity comparison can be found by integral method,when the hysteretic displacement reaches 80mm when the two energy difference of the maximum,10.87 kN · m,the maximum displacement grouting bellows specimens than cast-in-place specimens by the energy dissipation capacity of about 10%less.According to the comprehensive test results,the author believes that under the same design parameters,as long as the strength of the assembled pier joint is reliable,the performance of the bridge pier can be basically achieved.The paper introduces the process of the establishment of the pier model includes model element type,reinforced concrete constitutive relation and the choice of boundary conditions and loads by using the finite element analysis software ABAQUS.By comparing the results of finite element analysis and experimental results,the agreement degree is higher,to prove the rationality of establishing the test conclusion the correctness,reliability and model.It provides a reference for the simulation of the seismic performance of bridge piers in the future by ABAQUS.