In order to study the axial compression performances of short columns made of recycled aggregate concrete,four samples were designed with different recycled aggregate replacement rates and carbon fibre reinforced plas...In order to study the axial compression performances of short columns made of recycled aggregate concrete,four samples were designed with different recycled aggregate replacement rates and carbon fibre reinforced plastics(CFRP)sheets.Then,monotonic loading was implemented to assess the variation trends of their axial compression properties.The ABAQUS finite element software was also used to determined the compression performances.Good agreement between experimental and numerical results has been found for the different parameters being considered.As shown by the results,recycled coarse aggregates result in improved ductility and better deformation performance of the specimens.The failure of specimens caused by pre damage can be compensated by using CFRP sheets,by which both the resistance to deformation and the axial carrying capacity of columns can be increased.展开更多
If a long-distance gas pipeline is unavoidably buried under a planned high-filling road,the high fill subgrade setting will result in the change of the pipe's mechanical shape and the local stress concentration on...If a long-distance gas pipeline is unavoidably buried under a planned high-filling road,the high fill subgrade setting will result in the change of the pipe's mechanical shape and the local stress concentration on the pipe,which will pose threats to the safe operation of the pipeline.Protection culverts are generally adopted to solve this issue,but the construction of protection culverts are difficult and high in cost and usually unable to meet the requirements of construction schedule of the planned road project by the local government.For this reason,the stress on pipelines in high fill subgrade was analyzed and a rectification measure was proposed and its safety and rationality was also calculated.The results show that increasing pipe thickness is a feasible rectification measure.Thus,we analyzed the stability of and stress on the pipe caused by the uneven high fill setting by using the ABAQUS finite element software package,in which the pipe was simulated as the beam element,the backfill above the pipe as the stress load,and the elastic foundation underneath the pipe as the evenly-distributed spring.From the stress cloud charts,we can see the stress concentration on the pipe where a sudden change occurs in high fill setting.Without proper measures,accidents would be inevitable in the end.The analysis results from the ABAQUS also show that the scheme of increasing the pipe thickness will be the most cost-effective and practical way to deal with the stress resulted from the uneven high fill setting above the pipe.But it is pointed out that the pipeline laying route should avoid planned high filling roads as far as possible to ensure its safe operation.展开更多
A specific computational program SAFEM was developed based on semi-analytical finite element （FE） method for analysis of asphalt pavement structural responses under static loads. The reliability and efficiency of th...A specific computational program SAFEM was developed based on semi-analytical finite element （FE） method for analysis of asphalt pavement structural responses under static loads. The reliability and efficiency of this FE program was proved by comparison with the general commercial FE software ABAQUS. In order to further reduce the computational time without decrease of the accuracy, the infinite element was added to this program. The results of the finite-infinite element coupling analysis were compared with those of finite element analysis derived from the verified FE program, The study shows that finite-infinite element coupling analysis has higher reliability and efficiency.展开更多
文摘In order to study the axial compression performances of short columns made of recycled aggregate concrete,four samples were designed with different recycled aggregate replacement rates and carbon fibre reinforced plastics(CFRP)sheets.Then,monotonic loading was implemented to assess the variation trends of their axial compression properties.The ABAQUS finite element software was also used to determined the compression performances.Good agreement between experimental and numerical results has been found for the different parameters being considered.As shown by the results,recycled coarse aggregates result in improved ductility and better deformation performance of the specimens.The failure of specimens caused by pre damage can be compensated by using CFRP sheets,by which both the resistance to deformation and the axial carrying capacity of columns can be increased.
文摘If a long-distance gas pipeline is unavoidably buried under a planned high-filling road,the high fill subgrade setting will result in the change of the pipe's mechanical shape and the local stress concentration on the pipe,which will pose threats to the safe operation of the pipeline.Protection culverts are generally adopted to solve this issue,but the construction of protection culverts are difficult and high in cost and usually unable to meet the requirements of construction schedule of the planned road project by the local government.For this reason,the stress on pipelines in high fill subgrade was analyzed and a rectification measure was proposed and its safety and rationality was also calculated.The results show that increasing pipe thickness is a feasible rectification measure.Thus,we analyzed the stability of and stress on the pipe caused by the uneven high fill setting by using the ABAQUS finite element software package,in which the pipe was simulated as the beam element,the backfill above the pipe as the stress load,and the elastic foundation underneath the pipe as the evenly-distributed spring.From the stress cloud charts,we can see the stress concentration on the pipe where a sudden change occurs in high fill setting.Without proper measures,accidents would be inevitable in the end.The analysis results from the ABAQUS also show that the scheme of increasing the pipe thickness will be the most cost-effective and practical way to deal with the stress resulted from the uneven high fill setting above the pipe.But it is pointed out that the pipeline laying route should avoid planned high filling roads as far as possible to ensure its safe operation.
基金represented by German Federal Highway Research Institute (BASt)financed by the Federal Minister of Transport and Digital Infrastructure (BMVI)conducted under FE 04.0259/2012/NGB
文摘A specific computational program SAFEM was developed based on semi-analytical finite element （FE） method for analysis of asphalt pavement structural responses under static loads. The reliability and efficiency of this FE program was proved by comparison with the general commercial FE software ABAQUS. In order to further reduce the computational time without decrease of the accuracy, the infinite element was added to this program. The results of the finite-infinite element coupling analysis were compared with those of finite element analysis derived from the verified FE program, The study shows that finite-infinite element coupling analysis has higher reliability and efficiency.
