| In recent years,a major trend in the development of China's construction industry is the industrialization of housing.The Ministry of Housing and Urban-Rural Development and other relevant departments have issued several articles,demanding to increase the use rate of fabricated components in buildings,and strive to gradually realize the industrialization of housing;It can improve construction efficiency,reduce construction cost,shorten the construction period of buildings,ensure the quality of buildings throughout their life cycle,and be environmentally friendly,which is conducive to the construction of ecological civilization.The promotion of fabricated concrete structures is an important way to achieve this goal,and the problem of node connection has always been a key factor restricting the development of fabricated concrete structures.Only the performance of prefabricated structural joints is guaranteed,and the safety and application of the entire fabricated building is applicable.Sex and durability can be guaranteed,and housing industrialization can be realized as soon as possible.Based on the research results of node connection at home and abroad,this paper improves the lap joint connection technology used in the prefabricated concrete structure,and replaces the common grout with a self-developed high-strength grout.A new type of high-strength grout-based constrained slurry anchor lap joint technology,and the relationship between the lap length of this new joint technology and the hoop ratio of spiral stirrups is summarized;the force performance of this new joint technology is studied.According to the diameter of the steel bar and the length of the lap,the 96 lap joint specimens based on high-strength grouting were designed and fabricated.The uniaxial tensile test was carried out on the specimens,and the finite element software ABAQUS was used to test the test process.Numerical simulation,comparison of test results and simulation results show that the finite element method used in this paper is more feasible and the reliability of the calculation results is higher.On this basis,the hole diameter is continuously studied by the limit element method used in this paper.And the effect of the hoop ratio of the spiral stirrup on this new joining technology;in addition,this new joining technology is applied to the shear wall to study the cast-in-place wall This new precast wall using different connection technique in seismic performance.The main contents and results of this paper are as follows:(1)Summarizes the research results of related scholars on the joint connection problem in fabricated concrete structures,and combines the development status of fabricated concrete structures in China,and improves the existing technology of constrained slurry anchor lap joints.A new type of high-strength grout-based constrained slurry anchor lap joint technology,and the theoretical calculation formula for this new joint technology is derived.(2)For a more in-depth study of the force performance of this new type of high-strength grout-based constrained slurry anchor lap joint technology,16 sets of 96 were designed and manufactured with the diameter of the steel bar and the length of the longitudinal ribs as the variables.The test pieces were subjected to one-way drawing tests on the 96 test piecesaccording to the provisions in the Technical specification for mechanical splicing of steel reinforcing bars(JGJ 107-2016).By observing the yield load of the longitudinal reinforcement of the specimen during the loading process,the strain of the spiral stirrup,the ultimate load of the specimen and the distribution and development of the crack,the strain law of the spiral stirrup is analyzed,and the cause of the crack is analyzed.Etc.Finally,the limit overlap length of this new type of high-strength grout-based constrained slurry anchor lap joint technology is given.(3)Using ABAQUS finite element software to simulate all the test processes in this paper,and compare the simulation results with the test results.The simulation results are in good agreement with the test results.It proves that the finite element calculation method used in this paper is more feasible and the calculation results can be The reliability is higher.(4)Based on the experimental simulation,the influence of the diameter of the hole and the hoop ratio of the spiral stirrup on the new joint technology was studied by using the finite element software ABAQUS.The simulation results show that within the scope of the specification,the bearing capacity of the specimen increases with the increase of the hoop hoop ratio and the diameter of the hole.By increasing the variables,the performance of this new joint technology is deepened.Understand,provide a theoretical basis for the design and application of fabricated structural nodes.(5)Based on the previous simulation,this new type of high-strength grout-based constrained slurry anchor lap joint technology is applied to reinforced concrete shear wall structure,and the cast-in-place shear wall is studied and this new connection is adopted.The difference in seismic performance of technical prefabricated shear walls.The finite element software ABAQUS was used to simulate three cast-in-place walls and three prefabricated walls using this new connection technology.The seismic performance indexes such as load-displacement curve,ultimate bearing capacity,elastic stage stiffness and ductility were compared and analyzed.The simulation results show that the prefabricated shear wall with the new high-strength grout-based constrained slurry anchor lap joint technology has nearly the same ultimate bearing capacity as the cast-in-place shear wall,and the ductility index is better than the cast-in-place shear wall.Can be promoted.In this paper,a new type of high-strength grout-based constrained slurry anchor lap joint technology is theoretically and experimentally analyzed,and the new joint technology is numerically simulated by finite element software ABAQUS.The new connection technology of different variables is studied.The influence law,as well as the difference in seismic performance between the cast-in-situ shear wall and the prefabricated shear wall using this new connection technology,provides a theoretical basis for design and scientific research personnel. |
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