Seismic Experimental And Theory Study On Recycled Concrete Frame-Shear Wall

The seismic performance and the engineering application problems of the recycled concrete structure are the important parts of construction waste recycling, and they are also the science and technology problems concerned by the current domestic and international engineering. In the past, there were some research on the performance of recycled concrete materials and the basic components of the mechanical properties, but the papers on the seismic performance of recycled concrete structures were few, and works on the application of recycled concrete structure has yet to be developed. In this paper, systematically seismic experimental and theory study on recycled concrete frames, recycled concrete frame-shear walls and recycled concrete long columns have been done. Main contributions are as follows:1. The seismic performance tests of two 1/2.5 scaled recycled concrete frames and two recycled 1/2.5 scaled concrete frame-shear walls were completed under cyclic loading. The load-carrying capacity, stiffness and its attenuation process, ductility, hysteretic behavior, energy dissipation and failure phenomena of the specimens were comparatively analyzed. The finite element analysis on recycled concrete frames and recycled concrete frame-shear walls has been carried out, and the simulation results are in good agreement with the measured ones.2. The seismic performance tests of seven 1/2 scaled recycled concrete long columns were completed under cyclic loading. The load-carrying capacity, stiffness and its attenuation process, ductility, hysteretic behavior, energy dissipation and failure phenomena of the specimens were comparatively analyzed. The influences of recycled aggregate replacement rate, axial compression ratio and longitudinal reinforcement ratio on their seismic performance were focused in this paper. The finite element analysis on recycled concrete long columns has been carried out, and the simulation results are in good agreement with the measured ones.3. General regulations,section design methods and construction requirements on seismic structures of the recycled concrete frame structure and frame - shear wall structure were given in this paper.The main conclusions:1. With the increase of recycled aggregate replacement rate, the seismic performance of recycled concrete frame is decreased. The load-carrying capacity, ductility and energy dissipation of the frame structure made from recycled concrete reduced by 5%, 20% and 12% respectively compared to the frame structure with natural concrete in first floor and recycled concrete in the second floor. 2. With the increase of recycled aggregate replacement rate, the seismic performance of recycled concrete frame-shear wall is decreased. The load-carrying capacity, ductility and energy dissipation of the frame-shear wall structure made from recycled concrete reduced by 0.4%, 19% and 13% respectively compared to the frame-shear wall structure with natural concrete in the first floor and recycled concrete in the second floor.3. With the increase of recycled aggregate replacement rate, the seismic performance of recycled concrete long column is decreased. The load-carrying capacity, ductility and energy dissipation of the long column made from recycled concrete reduced by 7%, 3% and 19% respectively compared to the long column made from natural concrete4. Recycled concrete structure can be used for the multi-storey frame structure and the frame - shear wall structure in octave seismic fortification intensity area, or the top layers of high-rise structure in octave seismic fortification intensity area in the range of three floors.