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401.
The numerical simulation was carried out based on tensile test of the embedded components in segment joints of the deep buried storage and drainage shield-driven tunnel in Shanghai in order to study the numerical approach for mechanical analysis of segment joints of the tunnel. Using the concrete damage plasticity model and nonlinear springs, the 3D refined numerical model was established, in which the embedded components with complex geometries and the bond-slip behaviors between the concrete and bars were taken into consideration. Three kinds of embedded component models with different degrees of refinement were established and simply loaded. By comparing the calculation results and considering the spent time and the accuracy of calculation, the simplified form of the embedded components used in the overall model was determined. Nonlinear springs between anchor bars and concrete were set in the model in order to simulate the bond-slip behavior between them. In addition, two contrast models were also established using binding constraint and face-face contact constraint between concrete and anchor bars respectively. The three types of models were loaded in accordance with the test conditions. Comparing the results of the numerical calculation with the test results, it is shown that the "nonlinear spring model", which takes the bond-slip behavior into consideration, is more consistent with the test results than the "face to face contact model" and "binding model". And the model also reflects the failure mode very well. It indicates that the three dimensional refined modeling method used in this paper is applicable for similar tensile tests. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   
402.
高性能混凝土的研究现状和发展应用   总被引:5,自引:0,他引:5  
简要介绍了国内外混凝土材料的发展现状,论述了高性能混凝土的研究现状和发展趋势。目前,混凝土正在向高强、高性能和生态化的方向发展,绿色高性能混凝土是混凝土材料的发展方向,其应用前景将越来越广阔。  相似文献   
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