Finite Element Study Of The Seismic Behavior Of New Type Joints For Precast Concrete Shear Wall Structures

With the rapid development of economy in our country, the proportion of the real estate industry keeps increasing in the GDP, a lot of new buildings stimulates the development of the construction industry, also drives the growth of the national economy, our country will be in a state of "building" for a long time.Prefabricated construction is an important part in all kinds of building structures. In the early 1980s, the prefabricated construction began to be popular in our country. But limited to the construction and the technical level, construction quality and safety can not be effectively guaranteed. In recent years, as the rapid development of the construction technology and the theoretical analysis of building structures, prefabricated structure have been proposed and adopted. Prefabricated structures has the quick construction speed, small pollution, the advantages of saving manpower than traditional cast-in-place construction method, it is a kind of construction method which is worth promoting. At present, the growing shortage of land resources makes the residential building structure to develop from the low-rise, multi-story to small high-rise, high-rise structure quickly. To the prefabricated construction modes for small high-level, high-rise shear wall structure, connection technology development and achievements transformation of the shear wall has become the key whether the prefabricated shear wall residential structure can take root in our country.Existing connection method of the fabricated shear wall structure are transplanted from foreign sleeve slurry grouting anchor connection technology. This kind of connection mode has successfully made some exploration to the node connection of the prefabricated shear wall structure, a variety of full scale wall node test and many practical engineering applications have proved that this kind of connection can satisfy the basic requirement of structure seismic. Although sleeve slurry grouting anchor connection has the above advantages, but its economical technology is not high, mainly reflects in:(1) the casting accuracy of the prefabricated wall and personnel construction skills need to be high, has gap from our casting level of precast production and constructing skills of construction team in our country at present stage. (2) The cost of the sleeve is relatively high, in turn, raise the economic cost of the project, so as to make the promote of the precast construction hard in China. For these reasons, this paper puts forward a new kind of connection named herringbone connecting type, this connection way without any increase in technology and material cost, relying on the domestic existing precision level of production casting and technical level of construction team, can realize the field assembly connection. This topic does a systematic in-depth numerical simulation research on seismic performance of connecting node of the prefabricated shear wall, the main research contents include:(1) Comprehensively summarized the development of the connection of the prefabricated shear wall structure.(2) According to the actual structure of new connections, use the finite element software to establish the corresponding three-dimensional finite element static analysis model, study the mechanical performance of the shear walls under the uniaxial load using numerical simulation, and compared with the cast-in-place connection, get its mechanical characteristics under uniaxial load. Research results show that the fabricated shear wall under uniaxial load has the same mechanical characteristics to the cast-in-place shear wall, local stiffness is improved, mechanical performance has a certain security.(3) On the basis of the prefabricated shear wall finite element model, apply low-cyclic load to the model, draw hysteresis curve, inspects its energy dissipation capability. Through the comparison of analysis results, the energy dissipation ability of the proposed wall node model is better than the cast-in-place connection node model in elastic stage, after achieving ultimate load, the energy dissipation ability becomes less than cast-in-place node model, the stiffness degradation faster than that of cast-in-place node model, this main because the reinforced is less than the cast-in-place model, leads to the steel yield early.(4) Through changing the axial compression ratio of prefabricated shear wall, study the effect of axial pressure ratio on the energy dissipation capacity. The results show that with the increase of axial compression ratio, the energy dissipation capacity of the shear wall declines, but the ultimate load increases.Through the comparison of the two connection node model, the mechanical characteristics of the prefabricated node connecting model is similar to the cast-in-place node model, seismic performance is good, has certain theory significance, provide the basis for future research.