Utilization of urban underground space has become a vital approach to alleviate the strain on urban land resources,and to optimize the structure and pattem of the city.It is also very important to improve the city env...Utilization of urban underground space has become a vital approach to alleviate the strain on urban land resources,and to optimize the structure and pattem of the city.It is also very important to improve the city environment,build livable city and increase the capacity of the city.Based on the analysis of existing evaluation methods and their problems,a method for evaluating underground space resources based on a negative list of adverse factors affecting underground space development is proposed,to be primarily used in urban planning stages.A list of the adverse factors is established,including limiting factors,constraining factors and influencing factors.Taking Xi'an as an example,using a geographical information system platform,a negative list of adverse factors for the underground space resources in Xi'an City are evaluated,and preventive measures are proposed.Natural resources,exploitable resources,and the potential growth of exploitable underground space resources are evaluated.Underground space assessment in the different development stages of the city,collaborative utilization and safety evaluation for multiple subsurface resources,environmental impact and assessment,as well as evaluation methods based on big data and intelligent optimization algorithms are all discussed with the aim of serving city planning and construction.展开更多
The building cooling load is calculated in most standards using the sol-air temperature(T_(sol-air)),which depends on the surface properties and the building configuration.This study presents an experimental and numer...The building cooling load is calculated in most standards using the sol-air temperature(T_(sol-air)),which depends on the surface properties and the building configuration.This study presents an experimental and numerical analysis to find a relationship between the aspect ratio of the courtyard and the T_(sol-air) at different height levels.Besides,the influence of the surface reflection factor on the T_(sol-air) is analyzed.The results show that the T_(sol-air) inside the courtyard differs compared to the usual outside facade.This difference is increased by increasing the aspect ratio of the courtyard and can reach up to 60°C at low levels of the deep courtyards.It is also found that the courtyard geometry is much more important than the thermal behavior of the materials and the T_(sol-air) within the deep courtyard is less affected by the reflection factor of materials.展开更多
基金This research is supported by National Key Research and Development Project,Ministry of Science and Technology of the People’s Republic of China(2018YFC1504700).
文摘Utilization of urban underground space has become a vital approach to alleviate the strain on urban land resources,and to optimize the structure and pattem of the city.It is also very important to improve the city environment,build livable city and increase the capacity of the city.Based on the analysis of existing evaluation methods and their problems,a method for evaluating underground space resources based on a negative list of adverse factors affecting underground space development is proposed,to be primarily used in urban planning stages.A list of the adverse factors is established,including limiting factors,constraining factors and influencing factors.Taking Xi'an as an example,using a geographical information system platform,a negative list of adverse factors for the underground space resources in Xi'an City are evaluated,and preventive measures are proposed.Natural resources,exploitable resources,and the potential growth of exploitable underground space resources are evaluated.Underground space assessment in the different development stages of the city,collaborative utilization and safety evaluation for multiple subsurface resources,environmental impact and assessment,as well as evaluation methods based on big data and intelligent optimization algorithms are all discussed with the aim of serving city planning and construction.
文摘The building cooling load is calculated in most standards using the sol-air temperature(T_(sol-air)),which depends on the surface properties and the building configuration.This study presents an experimental and numerical analysis to find a relationship between the aspect ratio of the courtyard and the T_(sol-air) at different height levels.Besides,the influence of the surface reflection factor on the T_(sol-air) is analyzed.The results show that the T_(sol-air) inside the courtyard differs compared to the usual outside facade.This difference is increased by increasing the aspect ratio of the courtyard and can reach up to 60°C at low levels of the deep courtyards.It is also found that the courtyard geometry is much more important than the thermal behavior of the materials and the T_(sol-air) within the deep courtyard is less affected by the reflection factor of materials.
