Over the last decades,geo-structures are experiencing a rapid development in China.The potential risks inherent in the huge amount of construction and asset operation projects in China were well managed in the major p...Over the last decades,geo-structures are experiencing a rapid development in China.The potential risks inherent in the huge amount of construction and asset operation projects in China were well managed in the major project,i.e.the project of Shanghai Yangtze tunnel in 2002.Since then,risk assessment of geostructures has been gradually developed from a qualitative manner to a quantitative manner.However,the current practices of risk management have been paid considerable attention to the assessment,but little on risk control.As a result,the responses to risks occurrences after a comprehensive assessment are basically too late.In this paper,a smart system for risk sensing incorporating the wireless sensor network(WSN) on-site visualization techniques and the resilience-based repair strategy was proposed.The merit of this system is the real-time monitoring for geo-structural performance and dynamic pre-warning for safety of on-site workers.The sectional convergence,joint opening,and seepage of segmental lining of shield tunnel were monitored by the micro-electro-mechanical systems(MEMS) based sensors.The light emitting diode(LED) coupling with the above WSN system was used to indicate different risk levels on site.By sensing the risks and telling the risks in real time,the geo-risks could be controlled and the safety of geo-structures could be assured to a certain degree.Finally,a resilience-based analysis model was proposed for designing the repair strategy by using the measured data from the WSN system.The application and efficiency of this system have been validated by two cases including Shanghai metro tunnel and underwater road tunnel.展开更多
There are various faults in northern and southern margins of Torbat-e-Jam-Fariman plain which show the probability of enormous earthquake in the future.In present study the geomorphic indices contain Asymmetry Functio...There are various faults in northern and southern margins of Torbat-e-Jam-Fariman plain which show the probability of enormous earthquake in the future.In present study the geomorphic indices contain Asymmetry Function(Af),Sinuosity of mountain front(Smf),Valley floor index(Vf),Hypsometric index(Hi),Mean Axial slope of channel index(MASC)and Drainage Basin Shape(Bs),have been utilized to determine the relative tectonic activity index(IAT)to recognize,eventually,the geo-structural model of the study area.Faults and folds control the geo-structural activities of the study area,and the geomorphic indices are being affected in consequence of their activities.The intensity of these activities is different throughout the plain.There are many geomorphic evidences,related to active transform fault which are detectable all over the study area such as deviated rivers,quaternary sediments transformation,fault traces.Therefore,recognition of geo-structural model of the study area is extremely vital.Field study,then,approved the results of geomorphic indices calculation in determining the geo-structural model of the study area.Results depicted that the geostructural model of the study area is a kind of Horsetail splay form which is in accordance to the relative tectonic activity of the study area.Based on the above mentioned results it can be predicted that the splays are the trail of Neyshabour fault.展开更多
This study focuses on the field reconnaissance efforts for investigating ground deformation behavior and building foundation performance in Iskenderun.Many structures experienced significant damage or collapsed due to...This study focuses on the field reconnaissance efforts for investigating ground deformation behavior and building foundation performance in Iskenderun.Many structures experienced significant damage or collapsed due to strong ground shaking in the coastal Iskenderun district of Hatay during the 2023 Kahramanmaras earthquake sequence.Many buildings were also impacted by ground failure due to liquefaction of deposits in the area.Preliminary information regarding the general subsurface profile and post-earthquake data collected during the reconnaissance was used to perform simplified liquefaction and lateral spreading analyses.The empirical methods provide first order estimations of settlements and lateral spreading but are not sufficient when the nature of the structure-soil-structure interaction and earthquake sequence is considered.Measurements of vertical displacements and building tilt,liquefaction manifestations,and structural and foundation parameters potentially affecting foundation settlements including foundation geometry,building contact pressure,and building elastic period were used to evaluate seismic response of the ground and the structures through empirical procedures.Most of the buildings exhibited poor to mediocre foundation performance due to liquefaction-prone subsurface profiles,especially on the coastline.Ongoing field and numerical research will reveal the cause of significant ground failure in the area as well as refined estimates for the seismic deformations.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.51278381,51538009 and 51608380)the International Research Cooperation Project of Shanghai Science and Technology Committee(Grant No.15220721600)the Peak Discipline Construction on Civil Engineering of Shanghai Project
文摘Over the last decades,geo-structures are experiencing a rapid development in China.The potential risks inherent in the huge amount of construction and asset operation projects in China were well managed in the major project,i.e.the project of Shanghai Yangtze tunnel in 2002.Since then,risk assessment of geostructures has been gradually developed from a qualitative manner to a quantitative manner.However,the current practices of risk management have been paid considerable attention to the assessment,but little on risk control.As a result,the responses to risks occurrences after a comprehensive assessment are basically too late.In this paper,a smart system for risk sensing incorporating the wireless sensor network(WSN) on-site visualization techniques and the resilience-based repair strategy was proposed.The merit of this system is the real-time monitoring for geo-structural performance and dynamic pre-warning for safety of on-site workers.The sectional convergence,joint opening,and seepage of segmental lining of shield tunnel were monitored by the micro-electro-mechanical systems(MEMS) based sensors.The light emitting diode(LED) coupling with the above WSN system was used to indicate different risk levels on site.By sensing the risks and telling the risks in real time,the geo-risks could be controlled and the safety of geo-structures could be assured to a certain degree.Finally,a resilience-based analysis model was proposed for designing the repair strategy by using the measured data from the WSN system.The application and efficiency of this system have been validated by two cases including Shanghai metro tunnel and underwater road tunnel.
文摘There are various faults in northern and southern margins of Torbat-e-Jam-Fariman plain which show the probability of enormous earthquake in the future.In present study the geomorphic indices contain Asymmetry Function(Af),Sinuosity of mountain front(Smf),Valley floor index(Vf),Hypsometric index(Hi),Mean Axial slope of channel index(MASC)and Drainage Basin Shape(Bs),have been utilized to determine the relative tectonic activity index(IAT)to recognize,eventually,the geo-structural model of the study area.Faults and folds control the geo-structural activities of the study area,and the geomorphic indices are being affected in consequence of their activities.The intensity of these activities is different throughout the plain.There are many geomorphic evidences,related to active transform fault which are detectable all over the study area such as deviated rivers,quaternary sediments transformation,fault traces.Therefore,recognition of geo-structural model of the study area is extremely vital.Field study,then,approved the results of geomorphic indices calculation in determining the geo-structural model of the study area.Results depicted that the geostructural model of the study area is a kind of Horsetail splay form which is in accordance to the relative tectonic activity of the study area.Based on the above mentioned results it can be predicted that the splays are the trail of Neyshabour fault.
文摘This study focuses on the field reconnaissance efforts for investigating ground deformation behavior and building foundation performance in Iskenderun.Many structures experienced significant damage or collapsed due to strong ground shaking in the coastal Iskenderun district of Hatay during the 2023 Kahramanmaras earthquake sequence.Many buildings were also impacted by ground failure due to liquefaction of deposits in the area.Preliminary information regarding the general subsurface profile and post-earthquake data collected during the reconnaissance was used to perform simplified liquefaction and lateral spreading analyses.The empirical methods provide first order estimations of settlements and lateral spreading but are not sufficient when the nature of the structure-soil-structure interaction and earthquake sequence is considered.Measurements of vertical displacements and building tilt,liquefaction manifestations,and structural and foundation parameters potentially affecting foundation settlements including foundation geometry,building contact pressure,and building elastic period were used to evaluate seismic response of the ground and the structures through empirical procedures.Most of the buildings exhibited poor to mediocre foundation performance due to liquefaction-prone subsurface profiles,especially on the coastline.Ongoing field and numerical research will reveal the cause of significant ground failure in the area as well as refined estimates for the seismic deformations.