| In recent years, as development of science and technology and continuous innovation, which greatly promoted the rapid development of the construction industry. Building parts were assembled at the construction site, the traditional concept and practices of the housing construction has been completely changed. With the construction process of industrialization, all countries took the factory prefabrication of building parts and assembled construction as an important symbol of housing industry modernization.Great changes will be promoted by development of prefabricated building construction in the mode building field. In such a big situation, as a developing country, chinese construction industry is in a accelerating development golden time. Reducing energy consumption and pollution, protecting ecology and environment; using new materials, applicating new technology; improving project quality, improving work efficiency; reducing field operations; strengthening key technical innovation and system integration were contributed to the housing construction diversification and industrialization, which would be the trends of construction industry.In prefabricated buildings, prefabricated unit were connected by the grouting sleeve for rebars splicing to form a whole, to resist a variety of adverse external loads. Because prefabricated beams and columns were manufactured in a factory, and its quality was good, however, the joint of each component was weak, which would form a unfavorable structure of strong beam and column-weak nodes. The node destruction was the main way in prefabricated buildings in the earthquake damaged. Thus, in prefabricated buildings, the grouting sleeve for rebars splicing played a decisive role! With the funds support of National Natural Science Foundation of China (Grant No.51278312), static response of grouting sleeve for rebars splicing was studied by ABAQUS finite element software. The main research contents include:(1) From the view of the connection of large diameter load-bearing bar, its several methods of rebars connection, advantages and disadvantages of connection ways were summarized comprehensively.(2) According to the actual structure of grouting sleeve for rebars splicing, the numerical model of grouting sleeve for rebars splicing was established at static response along the axial direction. The results showed that umbrella-shaped annular compressed grouting material columns were formed to transfer load between rebar and sleeve.(3) Based on the above finite element model, changing the friction coefficient between the sleeve and grouting material (sleeve surface roughness), results showed that the value of friction coefficient had not influence on mechanical properties of grouting coupler for rebars splicing.(4) By changing the distribution of sleeve rib, influencing factors of grouting coupler for rebars splicing were studied. The results indicated that sleeve rib spacing was ranged between 28mm and 14mm, the grouting material could effectively transfer load between the rebar and the sleeve. When the sleeve rib spacing was too large, the grouting material stress was uniform, some parts grouting material Min. principal stress was far beyond grouting material compressive strength; when the sleeve rib spacing was too small, grouting material was sheared, through the shearing stress mainly, grouting material transfer the load between the rebar and load. Grouting material was easy to shear failure, even rebar was pulled out from the sleeve.(5) The numerical model of grouting sleeve for rebars splicing that sleeve rib spacing was 14mm was established, changing the parameter of grouting material axial compressive strength, the results showed that with the axial compressive of grouting material increased, rebar was controlled more and more strongly by grouting material, rebar displacement decreased, and the biggest Min. principal stress also decreased gradually. |
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