Currently, traditional analysis and design methods are unreasonable in evaluating the performance and safety of pavements. The characteristic of shakedown theory lends itself particularly to the analysis of pavements....Currently, traditional analysis and design methods are unreasonable in evaluating the performance and safety of pavements. The characteristic of shakedown theory lends itself particularly to the analysis of pavements. Based on the lower bound shakedown theory, a simple and practical procedure for shakedown analysis of pavements has been developed using plastic strain energy as shakedown criteria via considering a special loading path. The proposed method is verified by using a homogeneous isotropic half space. Then, the method is applied to analyze a two-layered pavement. The dependence of shakedown limit on material properties of pavements is investigated in details. According to the analysis results, some valuable references are suggested for the selection of materials for accurate evaluation of the bearing performance of pavement under traffic loading.展开更多
This paper presents an application of strut-and-tie model(STM) to design the interior anchorage zone(IAZ) in the post-tensioned concrete structure.The STM theory and range of IAZ are introduced.Then,based on the finit...This paper presents an application of strut-and-tie model(STM) to design the interior anchorage zone(IAZ) in the post-tensioned concrete structure.The STM theory and range of IAZ are introduced.Then,based on the finite element analysis,a series of simplified equations to calculate internal forces in IAZ are presented.Finally,the STM model for IAZ is given.In the proposed STM model,internal forces in ties vary with the dimension ratio and the eccentricity of load.The U-turn of internal forces is suggested to allocate rebar to resist bearing flexural tensile force.Compared with the FIP(International Federation for Prestressing) model,the proposed STM model is more reasonable and applicable.展开更多
基金the National High Technology Research and Development Program (863) of China(No. 2006AA09A103)the Shanghai Leading Academic Discipline Project (No. B208)
文摘Currently, traditional analysis and design methods are unreasonable in evaluating the performance and safety of pavements. The characteristic of shakedown theory lends itself particularly to the analysis of pavements. Based on the lower bound shakedown theory, a simple and practical procedure for shakedown analysis of pavements has been developed using plastic strain energy as shakedown criteria via considering a special loading path. The proposed method is verified by using a homogeneous isotropic half space. Then, the method is applied to analyze a two-layered pavement. The dependence of shakedown limit on material properties of pavements is investigated in details. According to the analysis results, some valuable references are suggested for the selection of materials for accurate evaluation of the bearing performance of pavement under traffic loading.
基金Foundation item: the National High Technology Research and Development Program (863) of China (No. 2006AA09A103) and the Shanghai Leading Academic Discipline Project (No. B208)
文摘This paper presents an application of strut-and-tie model(STM) to design the interior anchorage zone(IAZ) in the post-tensioned concrete structure.The STM theory and range of IAZ are introduced.Then,based on the finite element analysis,a series of simplified equations to calculate internal forces in IAZ are presented.Finally,the STM model for IAZ is given.In the proposed STM model,internal forces in ties vary with the dimension ratio and the eccentricity of load.The U-turn of internal forces is suggested to allocate rebar to resist bearing flexural tensile force.Compared with the FIP(International Federation for Prestressing) model,the proposed STM model is more reasonable and applicable.