Comparative Study On Mechanical Properties Of New Fabricated Concrete Beam-column Dry Joints

With the development of construction industrialization,the application of prefabricated buildings is becoming more and more extensive.Prefabricated buildings have the advantages of short construction period,convenient and efficient construction,resource saving,green environmental protection,etc.It has broad development prospects in the domestic and foreign construction industry.In the development of prefabricated buildings,the research on the connection of prefabricated nodes is the key point of the development of industrialization of buildings.However,there are still insufficient researches on the development of prefabricated nodes at home and abroad.This paper combines relevant domestic and foreign research materials,through experiments and simulations.Combined with the analysis,I conducted an in-depth study on it.This article is based on the sub-project of the National Key Thirteenth Five-Year Key R&D Program "Key Technologies of Industrialized Building Design" "Form,Force Performance and Design Methods of High Deformability Prefabricated Joints"(2016YFC0701507-2).A new type of assembled concrete beam-column dry joint using two different connection forms of high-strength bolts and Q345 B ordinary bolts is introduced.The mechanical properties of two sets of new-style assembled concrete beam-column dry joints were studied through experiments and finite element numerical simulation analysis.The main contents of the research include bearing capacity,stiffness,energy dissipation performance,hysteresis curve,skeleton curve and ductility Performance,etc.,the main results of its research are as follows:(1)The deformation and failure of the two sets of new assembled concrete dry joints in the test and simulation process are cracked in a symmetrical form along the top surface of the T-shaped prefabricated beam end and the bottom surface to the other beam end,and the final failure deformation is mainly concentrated at the node of the T-shaped precast beam end Connected to the core area,the prefabricated column with corbels is basically intact,meeting the design requirements of “strong column and weak beam”.(2)For the overall study of the two sets of test components,the stiffness of the new assembled concrete beam-column dry joints of the two sets of tests is relatively similar,and the energy consumption is superior,and the load capacity of the two sets of test specimens is relatively similar.(3)The finite element numerical simulation verified the reliability of the newassembled concrete dry-type joints under the connection of the low-cycle reciprocating test.The joint yield stage,the bolt is the main load-bearing test piece,and the concrete precast beam is the secondary load-bearing test When the prefabricated columns and prefabricated beams meet the load-bearing capacity requirements,the prefabricated specimens can be repaired by replacing the bolts.This design meets the design concept of the new assembled concrete dry joint.(4)For the overall test components,the stiffness degradation of the new assembled concrete beam-column dry joints of the two groups of tests is relatively close,and both have good ductility.However,under low-cycle reciprocating loading analysis,the hysteresis curve is relatively full.The load-bearing capacity is relatively close,and they are all suitable for assembled frame structures.In summary,the experimental analysis and numerical simulation analysis of the new-style assembled concrete dry joints studied in this paper provide a new design method and corresponding theoretical basis for the future research of assembled joints.Figure [54] table [12] reference [65]...