As urban construction continues to develop and automobile ownership rises,parking shortages in cities have become increasingly acute.Given the limited availability of land resources,conventional underground garages an...As urban construction continues to develop and automobile ownership rises,parking shortages in cities have become increasingly acute.Given the limited availability of land resources,conventional underground garages and parking buildings no longer suffice to meet the growing demand for parking spaces.To address this dilemma,underground parking shaft(UPS)has emerged as a highly regarded solution.This study provides an overview of the layout scheme,structural design approaches,and construction techniques for UPS,focusing on the characteristics of intensive construction demonstrated in the project located in the Jianye District of Nanjing.Compared to conventional vertical shaft garage construction methods,this assembly parking shaft offers advantages such as a smaller footprint,higher prefabrication rate,shorter construction period,and reduced environmental impact.It presents an efficient approach for the intensive construction of urban underground spaces,particularly in areas with limited land and complex environments,showing promising prospects for widespread application.展开更多
Intensive construction methods offer benefits for metro station development,yet they present challenges for seismic design due to the spatially asymmetric configuration of passageway-shaft structures.In this study,a d...Intensive construction methods offer benefits for metro station development,yet they present challenges for seismic design due to the spatially asymmetric configuration of passageway-shaft structures.In this study,a detailed numerical model of a station-passageway-shaft structure system built using intensive construction methods was developed and the deformation and damage modes under seismic loadings were analyzed.The results indicate that inconsistent deformation between the shaft and the station generates interaction through the connecting passageway,leading to damage near the opening of the station structure and both ends of the connecting passageway Damage is more severe under longitudinal excitation.Compared with the opening plan that spans four segments,the opening plan that spans five segments exacerbates the overall degree of damage to the structure system.Under transverse excitation,the presence of interior structures intensifies the damage to the station and connecting passageway,while with such internal structure in place the impact is relatively minor under longitudinal excitation.Reinforcement with steel segments near the station opening can appreciably attenuate the damage.In contrast,introducing flexible joints at both ends of the connecting passageway intensifies the damage.Hence,reinforcement using steel segments emerges as an optimal seismic mitigation strategy.展开更多
The infrastructure in the urban core area is becoming increasingly dense,leading to restrictions on intensive development;however,there is a lack of adequate research on the structural mechanics of quasi-rectangular p...The infrastructure in the urban core area is becoming increasingly dense,leading to restrictions on intensive development;however,there is a lack of adequate research on the structural mechanics of quasi-rectangular pipe jacking tunnels.This paper presents an experimental investigation that was conducted to analyze the impact of ground surcharge on the structural behavior of a quasi-rectangular tunnel located at Jing’an Temple station of Shanghai Rail Transit Line 14.The experimental setup included a scaled-down model of a quasi-rectangular tunnel,which was considered to be typical of underground structures.A series of tests were carried out by applying varying surcharge loads and eccentricities on the ground surface located above the tunnel.The tunnel structure’s response was monitored and analyzed through the use of earth pressure gauges,displacement sensors,and strain gauges.The experimental results revealed that ground surcharge on existing tunnels is mainly influenced by eccentricity and depth,with distinct effects at zero eccentricity and increasing eccentricity.Shallow tunnel burial depths intensify the impact of ground surcharge on the tunnel structure.展开更多
基金Shanghai Science and Technology Innovation Action Plan(No.21DZ2204700)Shanghai Building Materials Research Project Plan(No.2022-005-006).
文摘As urban construction continues to develop and automobile ownership rises,parking shortages in cities have become increasingly acute.Given the limited availability of land resources,conventional underground garages and parking buildings no longer suffice to meet the growing demand for parking spaces.To address this dilemma,underground parking shaft(UPS)has emerged as a highly regarded solution.This study provides an overview of the layout scheme,structural design approaches,and construction techniques for UPS,focusing on the characteristics of intensive construction demonstrated in the project located in the Jianye District of Nanjing.Compared to conventional vertical shaft garage construction methods,this assembly parking shaft offers advantages such as a smaller footprint,higher prefabrication rate,shorter construction period,and reduced environmental impact.It presents an efficient approach for the intensive construction of urban underground spaces,particularly in areas with limited land and complex environments,showing promising prospects for widespread application.
基金The authors are grateful for the financial support from National Natural Science Foundation of China(Grant Nos.52061135112 and U1934210)the National Key Research and Development Program of China(No.2021YFE0114100)the China Scholarship Council(No.202206260188).
文摘Intensive construction methods offer benefits for metro station development,yet they present challenges for seismic design due to the spatially asymmetric configuration of passageway-shaft structures.In this study,a detailed numerical model of a station-passageway-shaft structure system built using intensive construction methods was developed and the deformation and damage modes under seismic loadings were analyzed.The results indicate that inconsistent deformation between the shaft and the station generates interaction through the connecting passageway,leading to damage near the opening of the station structure and both ends of the connecting passageway Damage is more severe under longitudinal excitation.Compared with the opening plan that spans four segments,the opening plan that spans five segments exacerbates the overall degree of damage to the structure system.Under transverse excitation,the presence of interior structures intensifies the damage to the station and connecting passageway,while with such internal structure in place the impact is relatively minor under longitudinal excitation.Reinforcement with steel segments near the station opening can appreciably attenuate the damage.In contrast,introducing flexible joints at both ends of the connecting passageway intensifies the damage.Hence,reinforcement using steel segments emerges as an optimal seismic mitigation strategy.
基金Financial support,jointly provided by the Ministry of Science and Technology of China(No.2021YFE0114100)the Federal Ministry of Education,Science,and Research(BMBWF)of Austria(No.CN11/2021)for the project“Intense Upgrades of the New Austrian Tunnelling Method(NATM)and Demonstration of its Applicability to High-Quality Urban Development”,is gratefully acknowledged+2 种基金the National Natural Science Foundation of China(Grant No.U1934210)the Science and Technology Commission of Shanghai Municipality(Nos.21DZ1203505,22DZ1203005,21DZ1202803,and 21DZ1202806)the Shanghai Rising-Star Program(No.22QB1405000)for their financial support of this work.
文摘The infrastructure in the urban core area is becoming increasingly dense,leading to restrictions on intensive development;however,there is a lack of adequate research on the structural mechanics of quasi-rectangular pipe jacking tunnels.This paper presents an experimental investigation that was conducted to analyze the impact of ground surcharge on the structural behavior of a quasi-rectangular tunnel located at Jing’an Temple station of Shanghai Rail Transit Line 14.The experimental setup included a scaled-down model of a quasi-rectangular tunnel,which was considered to be typical of underground structures.A series of tests were carried out by applying varying surcharge loads and eccentricities on the ground surface located above the tunnel.The tunnel structure’s response was monitored and analyzed through the use of earth pressure gauges,displacement sensors,and strain gauges.The experimental results revealed that ground surcharge on existing tunnels is mainly influenced by eccentricity and depth,with distinct effects at zero eccentricity and increasing eccentricity.Shallow tunnel burial depths intensify the impact of ground surcharge on the tunnel structure.
