Research On Seismic Performance Of Pretressed Precast Concrete Frame Structures Based On OpenSEES

In the past domestic and foreign structural tests and numerical simulation methods,the scholars of various countries have considered the prestressed fabricated frame nodes in the rigid domain.However,in the large amount of seismic data,the framework is very likely to be shear damaged due to the core of the node.The anchor fails and causes an overall collapse.Considering the seismic performance analysis of the prestressed fabricated frame of the joint model,the author applied OpenSEES to compile the calculation program of the low-cycle reciprocating load test and the pseudo-dynamic load test of the prestressed concrete frame structure,and selected the domestic researcher.Three tests:(1)low-cycle reciprocating load test of one-layer two-span prestressed concrete frame;(2)pseudo-dynamic test of one-two-two-span two-span prestressed assembled frame;(3)The pseudo-dynamic load test of the single-layer three-span prestressed assembled frame was numerically simulated and analyzed,and the calculated hysteresis curves and time-history curves were obtained respectively.In addition,the author selects the arrangement form of the prestressed tendons,the hoop characteristic value of the core part of the assembled joint,the axial compression ratio of the top of the frame column,and the prestressing degree of the prestressed assembled beam to influence the parameters of the prestressed assembly frame.Analyze and make some suggestions for prestressed assembly based on the simulation results of OpenSEES.The specific research contents are as follows:(1)By reading the literatures of researchers at home and abroad,the research status of prestressed assembly domestic and foreign scholars is expounded,and the experimental and numerical simulation methods of prestressed assembly frames at home and abroad are summarized.(2)Explain in detail the force transmission mechanism of the core zone of prestressed frame structure beam-column joints,and introduce the simplified two-dimensional analysis of the beam-column connected rotating spring and the node core zone shear spring in OpenSEES finite element analysis software.Node model(Joint2D).Using the above node model and the beam-column model based on the displacement method and the truss model of the prestressed tendons,the finite element analysis program of the prestressed prefabricated concrete frame structure considering Joint2 D unit is compiled,and the domestic scholars have completed thesingle layer double span.The prestressed assembled frame pseudo-static test was simulated and analyzed.The results of the experimental simulations were compared with the node models considered by the predecessors considering the study slip.Comparing the calculation results,the results obtained by the Joint2 D unit simulation agree well with the experimental results.Based on this conclusion,a method for quasi-static numerical simulation of prestressed fabricated frame using a simplified two-dimensional joint model is obtained.(3)Using the finite element analysis program,the domestic scholars have completed the simulation and analysis of the prestressed assembly frame pseudo-dynamic test of double-layer double-span and single-span three-layer prestressed assembly.The calculation results can reflect the characteristics of the prestressed fabricated frame in the dynamic test,and verify the accuracy and applicability of the analytical program in the pseudo-dynamic test.(4)The author compiled the calculation program of the multi-turn prestressed assembly frame with the arrangement of the prestressed tendons,the prestressed degree of the fabricated beam,the axial compression ratio of the top of the column,and the hoop characteristic value of the core area of the joint.The dynamic calculation of the prestressed assembly frame is carried out.According to the calculation results,the energy dissipation coefficient and the ductility coefficient of the frame are obtained,and corresponding design suggestions are proposed based on the results.