To achieve rational and precise seismic response predictions of large span spatial structures(LSSSs),the inherent non-uniformity and multidimensionality characteristics of earthquake ground motions should be properly ...To achieve rational and precise seismic response predictions of large span spatial structures(LSSSs),the inherent non-uniformity and multidimensionality characteristics of earthquake ground motions should be properly taken into consideration.However,due to the limitations of available earthquake stations to record seismic rotational components,the effects of rocking and torsional earthquake components are commonly neglected in the seismic analyses of LSSSs.In this study,a newly developed method to extract the rocking and torsion components at any point along the area of a deployed dense array from the translational earthquake recordings is applied to obtain the rotational seismic inputs for a LSSS.The numerical model of an actual LSSS,the Dalian International Conference Center(DICC),is developed to study the influences of multi-support and multidimensional excitations on the seismic responses of LSSSs.The numerical results reveal that the non-uniformity and multidimensionality of ground motion input can considerably affect the dynamic response of the DICC.The specific degree of influence on the overall and local structural displacements,deformations and forces are comprehensively investigated and discussed.展开更多
Based on the former performance capacity experiments of the magnet-friction energy dissipation devices, including the permanent magnet-friction energy dissipation device (PMF) and electromagnet-friction energy dissipa...Based on the former performance capacity experiments of the magnet-friction energy dissipation devices, including the permanent magnet-friction energy dissipation device (PMF) and electromagnet-friction energy dissipation devices (EMF), a 5-story steel frame model with spacious first story is designed and made according to a scale of 1/4. The magnet-friction energy dissipation devices can realize continuously varied controlling force, with rapid response and reverse recognition. Therefore, they overcome shortcomings usually found in energy dissipation devices whose force models are invariable. The two kinds of devices were fixed on the flexible first story of the structure model, and the shaking table tests have been carried out, respectively. In these tests, the performance of the devices and their effectiveness in structural control were confirmed. In this paper, the test results and analysis are discussed.展开更多
Shallow-buried large-span tunnels may bend or collapse owing to loads,and their surface structures present considerable safety issues.At Huashanyilu station on Qingdao Metro Line 6 in China,theoretical studies and int...Shallow-buried large-span tunnels may bend or collapse owing to loads,and their surface structures present considerable safety issues.At Huashanyilu station on Qingdao Metro Line 6 in China,theoretical studies and interior model tests were conducted to effectively increase the bearing capacity of the tunnel.The anchoring bearing mechanism of the high prestress compensating support system was revealed,and the system was built using a negative Poisson’s ratio(NPR)bolt at its core.We compared and analyzed the fracture evolution characteristics of the compensating and conventional support systems under various loads.The results showed that the compensating support system effectively increased the support strength and residual safety factor of the bearing arch,whereas the use of a high-prestress NPR anchor reduced the early deformation of the surrounding rock.The coupling failure modes of the arch tension extrusion failure and arch foot shear fracture occurred when the tunnel surrounding the rock was overloaded.The compensatory support system produces a bearing arch that is extremely resistant to external loads with minimal deformation of the tunnel surface and arch frame,excellent surrounding rock integrity,and a low stress rate.The radial and tangential peak stresses exceeded those of the passive support system,and the structural block fell when it became unstable.The maximum displacement of the arch stays constant at−5.7 mm after tunnel excavation.NPR bolts have remarkable applications in this field.The conclusions of this study have a significant impact on the regulation of the stability of the surrounding rock in large-span tunnels.展开更多
1 Background As the basic principle of the world economy,environment,and social development,sustainable development is the focus of the international community today.In the Olympic Agenda 2020 published by the Interna...1 Background As the basic principle of the world economy,environment,and social development,sustainable development is the focus of the international community today.In the Olympic Agenda 2020 published by the International Olympic Committee(IOC),sustainable development was officially listed as one of the core concepts of the Olympic Games.Since the beginning of the bid,the concept of ctathlete-centered,sustainable and economical”was proposed,which was highly consistent with the idea of the Olympic Agenda 2020.To implement the concept of holding“green”Olympic Games and meet the sustainability requirements of the IOC,the Organizing Committee of Beijing Winter Olympic Games issued a series of documents related to the sustainability of sports venues such as Sustainability Policies for 2022 Beijing Winter Olympic Games and Winter Paralympic Games,and strived to realize the sustainable development of sports venues in the whole life cycle of planning and design stage,construction stage,operation stage,and post-game utilization.展开更多
基金National Natural Science Foundation of China under Grant Nos.51738007,51808099the Fundamental Research Funds for the Central Universities under Grant No.DUT20RC(3)005。
文摘To achieve rational and precise seismic response predictions of large span spatial structures(LSSSs),the inherent non-uniformity and multidimensionality characteristics of earthquake ground motions should be properly taken into consideration.However,due to the limitations of available earthquake stations to record seismic rotational components,the effects of rocking and torsional earthquake components are commonly neglected in the seismic analyses of LSSSs.In this study,a newly developed method to extract the rocking and torsion components at any point along the area of a deployed dense array from the translational earthquake recordings is applied to obtain the rotational seismic inputs for a LSSS.The numerical model of an actual LSSS,the Dalian International Conference Center(DICC),is developed to study the influences of multi-support and multidimensional excitations on the seismic responses of LSSSs.The numerical results reveal that the non-uniformity and multidimensionality of ground motion input can considerably affect the dynamic response of the DICC.The specific degree of influence on the overall and local structural displacements,deformations and forces are comprehensively investigated and discussed.
文摘Based on the former performance capacity experiments of the magnet-friction energy dissipation devices, including the permanent magnet-friction energy dissipation device (PMF) and electromagnet-friction energy dissipation devices (EMF), a 5-story steel frame model with spacious first story is designed and made according to a scale of 1/4. The magnet-friction energy dissipation devices can realize continuously varied controlling force, with rapid response and reverse recognition. Therefore, they overcome shortcomings usually found in energy dissipation devices whose force models are invariable. The two kinds of devices were fixed on the flexible first story of the structure model, and the shaking table tests have been carried out, respectively. In these tests, the performance of the devices and their effectiveness in structural control were confirmed. In this paper, the test results and analysis are discussed.
基金the funding supports from the National Natural Science Foundation of China(Grant Nos.42377148 and 51674265)the National Key Research and Development Program(Grant No.2018YFC0603705).
文摘Shallow-buried large-span tunnels may bend or collapse owing to loads,and their surface structures present considerable safety issues.At Huashanyilu station on Qingdao Metro Line 6 in China,theoretical studies and interior model tests were conducted to effectively increase the bearing capacity of the tunnel.The anchoring bearing mechanism of the high prestress compensating support system was revealed,and the system was built using a negative Poisson’s ratio(NPR)bolt at its core.We compared and analyzed the fracture evolution characteristics of the compensating and conventional support systems under various loads.The results showed that the compensating support system effectively increased the support strength and residual safety factor of the bearing arch,whereas the use of a high-prestress NPR anchor reduced the early deformation of the surrounding rock.The coupling failure modes of the arch tension extrusion failure and arch foot shear fracture occurred when the tunnel surrounding the rock was overloaded.The compensatory support system produces a bearing arch that is extremely resistant to external loads with minimal deformation of the tunnel surface and arch frame,excellent surrounding rock integrity,and a low stress rate.The radial and tangential peak stresses exceeded those of the passive support system,and the structural block fell when it became unstable.The maximum displacement of the arch stays constant at−5.7 mm after tunnel excavation.NPR bolts have remarkable applications in this field.The conclusions of this study have a significant impact on the regulation of the stability of the surrounding rock in large-span tunnels.
文摘1 Background As the basic principle of the world economy,environment,and social development,sustainable development is the focus of the international community today.In the Olympic Agenda 2020 published by the International Olympic Committee(IOC),sustainable development was officially listed as one of the core concepts of the Olympic Games.Since the beginning of the bid,the concept of ctathlete-centered,sustainable and economical”was proposed,which was highly consistent with the idea of the Olympic Agenda 2020.To implement the concept of holding“green”Olympic Games and meet the sustainability requirements of the IOC,the Organizing Committee of Beijing Winter Olympic Games issued a series of documents related to the sustainability of sports venues such as Sustainability Policies for 2022 Beijing Winter Olympic Games and Winter Paralympic Games,and strived to realize the sustainable development of sports venues in the whole life cycle of planning and design stage,construction stage,operation stage,and post-game utilization.
