The Seismic Performance Study Of Earthquake-resilient Prefabricated Concrete Frame

Concrete frame is one of the main structure systems which is used to resist the lateral force and gravity load.Cast-in-place concrete frame consumes the earthquake energy via the plastic deformation,concrete crack and internal structural friction which will lead to the irreversible damage of the structure components and unrecoverable residual deformation.Then,it may cause the high repair cost and the damage to the equipment and personnel within the buildings,and therefore the great economic property lose cannot be avoided.The technology of precast concrete frame structure can control the quality of components,increase the speed of the construction and save the labor in the construction field.Thus,precast concrete frame structure is more and more popular.Nowadays,the main design method of precast concrete frame structure is emulating the cast-in-place concrete frame structure which make the seismic performance of the precast concrete frame structure be the same as that of the cast-in-place concrete frame structure.Thus,precast concrete frame structure will face the same problems as the cast-in-place concrete frame structure during the earthquake.In order to overcome these disadvantages mentioned above,in this study,the earthquake-resilient prefabricated concrete frame structure is put forward.This earthquake-resilient prefabricated concrete frame will make the structure return to the original status with the help of the elastic prestressed tendon after the earthquake.After replacing the external energy-dissipation rebars,the structure can continue to be in the service statue and resist other earthquake actions.During the earthquake,earthquake-resilient prefabricated concrete frame structure can consume the earthquake energy by the plastic deformation of the external energy-dissipation rebar and the opening/closing of the gaps between the concrete components.The main characteristics of the earthquake-resilient prefabricated concrete frame structure are shown below:1.The damage of the structure component is relatively small after the earthquake.2.The residual deformation of the structure can be basically ignored after the earthquake.According to the existing form of the external energy-dissipation rebar,the new external energy-dissipation rebar has been put forward.The material of this external energy-dissipation rebar is easy to reach and the production process is also simple that lead to a relatively lower cost than other energy-dissipation rebars.In this article,the design principle of the equal strength design method is used.The design of earthquake-resilient prefabricated concrete frame can be designed with strength capacity gotten from cast-in-place concrete frame.The initial stress value of the prestressed tendon and the area of the external energy-dissipation rebar can be calculated.After finishing the work mentioned above and considering the multiple diameters of the external energy-dissipation rebars,the finite element software ABAQUS is used to simulate the cast-in-place concrete frame and the earthquake-resilient prefabricated concrete frame based on the design parameters.Then,the relative result data can be obtained.In order to evaluate the influence of the initial stress value of the prestressed tendon to the resilience of the earthquake-resilient prefabricated concrete frame better,the initial stress value of the prestressed tendon will be changed based on the existing model,and there are two working conditions in the subsequent analysis: The initial stress value of the prestressed tendon within the precast concrete column will remain unchanged,and the initial stress value of the prestressed tendon within the precast concrete beam will cut 20% of the original initial stress value;The initial stress value of the prestressed tendon within the precast concrete beam will remain unchanged,and the initial stress value of the prestressed tendon within the precast concrete column will cut 20% of the original initial stress value.Through the simulation result,the conclusion of the research can be made below:The seismic performance of the earthquake-resilient prefabricated concrete frame structure is better than the cast-in-place concrete frame structure.After the loading process,the damage of the earthquake-resilient prefabricated concrete frame is relatively small and the residual deformation can be ignored.Also,the function of self-centering can be achieved.With the rise of the external energy-dissipation rebar’s diameter,the bearing capacity of the earthquake-resilient prefabricated concrete frame will increase and the function of self-centering is also be influenced.In the meantime,it can be observed that decreasing the initial stress value of the prestressed tendon within the concrete components may harm the resilience of the earthquake-resilient prefabricated concrete frame.