| Prefabricated concrete structure is widely used in the construction industry at home and abroad due to its advantages of fast construction,economy and environmental protection.And it’s also one of the most effective ways to realize the industrialization of construction in our country.In prefabricated buildings,the connection form of beam-column nodes is a key factor that affects the seismic performance of prefabricated structures.But there are still some shortcomings in domestic and foreign research on this.Therefore,this paper combines the research results at home and abroad,and uses a combination of experiments and finite element numerical simulation to further study the seismic performance of fabricated beam-column joints.This paper proposes a fabricated bolted RC beam-column node.A full-scale specimen of the node was made.The precast column was made of C80 high-strength concrete,the precast beam was made of C40 ordinary concrete,and the precast beam and column were connected by bolts.A low-cycle reciprocating load test was performed on the beam end of the joint specimen,and a three-dimensional simulation model of the joint was established using the finite element software ABAQUS,and the data was analyzed on the model.It was found that the numerical simulation and the experiment were in good agreement.On this basis,the test piece was analyzed with variable parameters,and the seismic performance of the test piece was analyzed by changing the bolt strength through experiments and changing the column concrete strength in the finite element model.The main research content and conclusions of this article are as follows:(1)Summarize and analyze the connection forms of existing prefabricated beam-column joints at home and abroad,based on the advantages and disadvantages of different joint forms.A fabricated bolted RC beam-column joint was proposed,and its seismic performance was studied through experiments and finite element numerical analysis.(2)The new type of node has shown good seismic performance and hysteresis performance through experiments and numerical simulations.During the test,the failure phenomenon mainly occurred at the junction of the T-beam end and the corbel column,and the cracks at the pressure steel plate of the beam were dense.The specimen finally suffered bending failure.There was no cracking in the prefabricated corbel column.It meets the seismic code requirements of "strong column and weak beam".(3)Through experiments,it is found that under the same loading system,the increase of bolt strength can effectively improve the bearing capacity and energy consumption capacity of joints to a certain extent.The stiffness of the node specimens connected by high-strength bolts is kept better.However,the joint specimens connected by ordinary bolts have a higher ductility coefficient.As the high-strength bolts slipped in the later stage of the test,their ductility was not fully utilized.Therefore,in actual construction,attention should be paid to the connection form between bolts and concrete.(4)Numerical simulation shows that under the same loading system,the change of column concrete strength has little effect on the hysteretic performance of the joint.When the concrete strength of the precast column and the precast beam are the same,the hysteretic curve of the joint is still full,and the seismic design requirements can also be met.Figure [46] table [10] reference [68]... |
PDF Full Text Request