The transformation and upgrading of comprehensive park can not be only limited to the adjustment for structure, function and landscape facility of comprehensive park itself, which shall be carried out as a whole. View...The transformation and upgrading of comprehensive park can not be only limited to the adjustment for structure, function and landscape facility of comprehensive park itself, which shall be carried out as a whole. Viewing from the macroscopic perspective of city, comprehensive park is an important constituent part of urban green space system, and its transformation is an integral part of overall perfection and development of urban green space system. Park is an organic integrity comprising many elements. The transformation of comprehensive park shall be carried out as a whole and handled by using the methods of "from top to bottom" and "from bottom to top", thus adjusting the relationship between park and city and within park on the whole. This research takes the open park transformation and upgrading of Xuzhou Quanshan Forest Park as an example to introduce the key points of open park transformation from such aspects as of entrance space, overall space structure, service function expansion and spatial form optimization in expectation of having a certain reference value.展开更多
For open car park structures,adopting a performance-based structural fire design is often justified and allowed because the fire does not reach flashover.However,this design approach requires an accurate assessment of...For open car park structures,adopting a performance-based structural fire design is often justified and allowed because the fire does not reach flashover.However,this design approach requires an accurate assessment of temperatures in structural members exposed to car fires.This paper describes a numerical study on the thermal exposure on steel framing members in open car park fires.Steel temperatures are computed by the coupling of computational fluid dynamics and finite element modeling,and by analytical models from the Eurocodes.In addition,the influence of galvanization on the steel temperature evolution is assessed.Results show that temperatures in unprotected beams and columns are influenced by the section geometry,car fire scenario,modeling approach,and use of galvanization.Galvanization slightly delays and reduces peak temperature.Regarding the different models,CFD-FEM(CFD:computational fluid dynamics,FEM:finite-element method)coupled models predict lower temperatures than the Hasemi model,because the latter conservatively assumes that the fire flame continuously touches the ceiling.Further,the Hasemi model cannot account for the effect of reduced emissivity from galvanization on the absorbed heat flux.Detailed temperature distributions obtained in the steel members can be used to complete efficient structural fire designs based on the member sections,structure layout,and use of galvanization.展开更多
文摘The transformation and upgrading of comprehensive park can not be only limited to the adjustment for structure, function and landscape facility of comprehensive park itself, which shall be carried out as a whole. Viewing from the macroscopic perspective of city, comprehensive park is an important constituent part of urban green space system, and its transformation is an integral part of overall perfection and development of urban green space system. Park is an organic integrity comprising many elements. The transformation of comprehensive park shall be carried out as a whole and handled by using the methods of "from top to bottom" and "from bottom to top", thus adjusting the relationship between park and city and within park on the whole. This research takes the open park transformation and upgrading of Xuzhou Quanshan Forest Park as an example to introduce the key points of open park transformation from such aspects as of entrance space, overall space structure, service function expansion and spatial form optimization in expectation of having a certain reference value.
基金This research was based in part upon work supported by ArcelorMittal Global R&D.This support is gratefully acknowledged.
文摘For open car park structures,adopting a performance-based structural fire design is often justified and allowed because the fire does not reach flashover.However,this design approach requires an accurate assessment of temperatures in structural members exposed to car fires.This paper describes a numerical study on the thermal exposure on steel framing members in open car park fires.Steel temperatures are computed by the coupling of computational fluid dynamics and finite element modeling,and by analytical models from the Eurocodes.In addition,the influence of galvanization on the steel temperature evolution is assessed.Results show that temperatures in unprotected beams and columns are influenced by the section geometry,car fire scenario,modeling approach,and use of galvanization.Galvanization slightly delays and reduces peak temperature.Regarding the different models,CFD-FEM(CFD:computational fluid dynamics,FEM:finite-element method)coupled models predict lower temperatures than the Hasemi model,because the latter conservatively assumes that the fire flame continuously touches the ceiling.Further,the Hasemi model cannot account for the effect of reduced emissivity from galvanization on the absorbed heat flux.Detailed temperature distributions obtained in the steel members can be used to complete efficient structural fire designs based on the member sections,structure layout,and use of galvanization.
