Single-layer reticulated dome structure are commonly high-profile building in the public and can be attractive targets for terrorist bombings,so the public can benefit from enhanced safety with a stronger understandin...Single-layer reticulated dome structure are commonly high-profile building in the public and can be attractive targets for terrorist bombings,so the public can benefit from enhanced safety with a stronger understanding of the behavior of single-layer reticulated dome structure under explosion.This paper investigates the fluid-structure interaction process and the dynamic response performance of the singlelayer reticulated dome under external blast load.Both experimental and numerical results shown that structural deformation is remarkably delayed compared with the velocity of blast wave,which advises the dynamic response of large-span reticulated dome structure has a negligible effect on the blast wave propagation under explosion.Four failure modes are identified by comparing the plastic development of each ring and the residual spatial geometric of the structure,i.e.,minor vibration,local depression,severe damage,and overall collapse.The plastic deformation energy and the displacement potential energy of the structure are the main consumers of the blast energy.In addition,the stress performance of the vertex member and the deep plastic ratio of the whole structure can serve as qualitative indicators to distinguish different failure modes.展开更多
The structural response of a single-layer reticulated dome to external explosions is shaped by many variables,and the associated uncertainties imply non-deterministic results.Existing deterministic methods for predict...The structural response of a single-layer reticulated dome to external explosions is shaped by many variables,and the associated uncertainties imply non-deterministic results.Existing deterministic methods for predicting the consequences of specific explosions do not account for these uncertainties.Therefore,the impact of the uncertainties associated with these input variables on the structures’response needs to be studied and quantified.In this study,a parametric uncertainty analysis was conducted first.Then,local and global sensitivity analyses were carried out to identify the drivers of the structural dynamic response.A probabilistic structural response model was established based on sensitive variables and a reasonable sample size.Furthermore,some deterministic empirical methods for explosion-resistance design,including the plane blast load model of CONWEP,the curved blast load model under the 50%assurance level,and the 20%mass-increased method,were used for evaluating their reliability.The results of the analyses revealed that the structural response of a single-layer reticulated dome to an external blast loading is lognormally distributed.Evidently,the MB0.5 method based on the curved reflector load model yielded results with a relatively stable assurance rate and reliability,but CONWEP did not;thus,the 1.2MB0.5 method can be used for making high-confidence simple predictions.In addition,the results indicated that the structural response is very sensitive to the explosion parameters.Based on these results,it is suggested that for explosion proofing,setting up a defensive barrier is more effective than structural strengthening.展开更多
南极作为地球的寒极,其最高点Dome A地区于2013年8月1日气温达到-93.0℃的极低值。利用Polar Weather Research and Forecasting(Polar WRF)3.8.1模式,对发生在南极Dome A地区的3次极端低温事件进行数值模拟分析。通过与自动气象站实测...南极作为地球的寒极,其最高点Dome A地区于2013年8月1日气温达到-93.0℃的极低值。利用Polar Weather Research and Forecasting(Polar WRF)3.8.1模式,对发生在南极Dome A地区的3次极端低温事件进行数值模拟分析。通过与自动气象站实测数据对比验证,模拟效果较为理想。结果表明:印度洋和大西洋交界区域的高压加强,其高压脊开始向南极内陆延伸,导致Dome A地区气压升高,使得该地区天气晴好,云量极低,为极端低温事件发生奠定基础;同时,南极中心冷涡加强,长时间的冷平流和稳定的逆温层为Dome A地区提供了足够的降温条件,并且加强了夜间辐射降温效应,稳定的垂直场、极低的向下长波辐射使得Dome A地区的极端低温事件得以维持。展开更多
Numerous isolated shallow seabed domes with depressions were discovered in the North Yellow Sea in a high-resolution multibeam echosounder survey. Twelve domes were located within a 11 km by 17 km survey area. The dom...Numerous isolated shallow seabed domes with depressions were discovered in the North Yellow Sea in a high-resolution multibeam echosounder survey. Twelve domes were located within a 11 km by 17 km survey area. The domes in this area were between 0.1 m and 1.0 m high with diameters ranging from 250 to 1 700 m. They were surrounded by corresponding depressions and displayed characteristic shapes ranging from circular to elliptical. The acoustic anomalies displayed on the high resolution sub-bottom profile images demonstrated that shallow gas accumulated just beneath these domes, suggesting that the migration and accumulation of the shallow gas caused the formation of these features. Accumulation atop the seabed domes and erosion within the depressions, as indicated by the lithological features of the sediment cores, suggested that seabed bottom currents also played a role in the formation and evolution of these features. In addition, the simultaneous decrease in the chlorite and sulfate content in core d pore water samples confirmed the presence of submarine fresh/brackish groundwater, which is of interest for hydrological budgets and may be a significant component of the regional hydrologic balance. Our findings suggested that shallow gas accumulation and migration are likely coupled to localized groundwater discharge at this domed site.展开更多
A series of thermal-structural-gneiss domes (briefly TSG domes) are developed in the Chinese Altaides. Sericite-chlorite zone, biotite zone, garnet zone, staurolite zone, kyanite (andalusite)zone, sillimanite- cordier...A series of thermal-structural-gneiss domes (briefly TSG domes) are developed in the Chinese Altaides. Sericite-chlorite zone, biotite zone, garnet zone, staurolite zone, kyanite (andalusite)zone, sillimanite- cordierite (sillimanite-garnet)zone, migmatite zone and migmatic granite- gneiss field are developed from the low-grade metamorphic area to the centre of the TSG domes. The succession of the formation and evolution of the progressive metamorphic zone, migmatite zone and migmatic granite-gneiss corresponds to the spatial sequence from the outer part to the centre of the TSG domes. The peak temperature of the metamorphism and granitization increases progressively from 400℃ to 800℃ while the pressure decreases progressively from 1.05 GPa to 0.10 GPa from the biotite zone to the migmatic granite-gneiss field. The metamorphism of the erogenic belt may be described by the pressure-temperature-space-time model (PTst). In the main episode of orogeny, the deep heat flow and structural flow upsurged展开更多
基金financial support from the China Postdoctora Science Foundation(project No.2021M690406)financial supports from the National Natural Science Foundation of China(project No.51708521,51778183)。
文摘Single-layer reticulated dome structure are commonly high-profile building in the public and can be attractive targets for terrorist bombings,so the public can benefit from enhanced safety with a stronger understanding of the behavior of single-layer reticulated dome structure under explosion.This paper investigates the fluid-structure interaction process and the dynamic response performance of the singlelayer reticulated dome under external blast load.Both experimental and numerical results shown that structural deformation is remarkably delayed compared with the velocity of blast wave,which advises the dynamic response of large-span reticulated dome structure has a negligible effect on the blast wave propagation under explosion.Four failure modes are identified by comparing the plastic development of each ring and the residual spatial geometric of the structure,i.e.,minor vibration,local depression,severe damage,and overall collapse.The plastic deformation energy and the displacement potential energy of the structure are the main consumers of the blast energy.In addition,the stress performance of the vertex member and the deep plastic ratio of the whole structure can serve as qualitative indicators to distinguish different failure modes.
基金the financial support from the China Postdoctora Science Foundation (project No. 2021M690406)the financial supports from the National Natural Science Foundation of China (project Nos. 51708521, 51778183)
文摘The structural response of a single-layer reticulated dome to external explosions is shaped by many variables,and the associated uncertainties imply non-deterministic results.Existing deterministic methods for predicting the consequences of specific explosions do not account for these uncertainties.Therefore,the impact of the uncertainties associated with these input variables on the structures’response needs to be studied and quantified.In this study,a parametric uncertainty analysis was conducted first.Then,local and global sensitivity analyses were carried out to identify the drivers of the structural dynamic response.A probabilistic structural response model was established based on sensitive variables and a reasonable sample size.Furthermore,some deterministic empirical methods for explosion-resistance design,including the plane blast load model of CONWEP,the curved blast load model under the 50%assurance level,and the 20%mass-increased method,were used for evaluating their reliability.The results of the analyses revealed that the structural response of a single-layer reticulated dome to an external blast loading is lognormally distributed.Evidently,the MB0.5 method based on the curved reflector load model yielded results with a relatively stable assurance rate and reliability,but CONWEP did not;thus,the 1.2MB0.5 method can be used for making high-confidence simple predictions.In addition,the results indicated that the structural response is very sensitive to the explosion parameters.Based on these results,it is suggested that for explosion proofing,setting up a defensive barrier is more effective than structural strengthening.
基金This research is supported by the Funded by the Natural Science Foundation of China(41876230,41376192)the Major National Scientifi c Research Project on Global Changes(973 Project)(2013CBA01804)Comprehensive Investigation&Assessment Programs(CHINARE2017-01-01).
基金Supported by the Strategic Priority Research Program,CAS(No.XDA19060402)the NSFC-Shandong Joint Fund for Marine Science Research Centers(No.U1606401)+1 种基金the International Partnership for Innovative Team Program(No.20140491526)the Chinese Academy of Sciences,and the Taishan Scholar Project Funding(No.tspd20161007)
文摘Numerous isolated shallow seabed domes with depressions were discovered in the North Yellow Sea in a high-resolution multibeam echosounder survey. Twelve domes were located within a 11 km by 17 km survey area. The domes in this area were between 0.1 m and 1.0 m high with diameters ranging from 250 to 1 700 m. They were surrounded by corresponding depressions and displayed characteristic shapes ranging from circular to elliptical. The acoustic anomalies displayed on the high resolution sub-bottom profile images demonstrated that shallow gas accumulated just beneath these domes, suggesting that the migration and accumulation of the shallow gas caused the formation of these features. Accumulation atop the seabed domes and erosion within the depressions, as indicated by the lithological features of the sediment cores, suggested that seabed bottom currents also played a role in the formation and evolution of these features. In addition, the simultaneous decrease in the chlorite and sulfate content in core d pore water samples confirmed the presence of submarine fresh/brackish groundwater, which is of interest for hydrological budgets and may be a significant component of the regional hydrologic balance. Our findings suggested that shallow gas accumulation and migration are likely coupled to localized groundwater discharge at this domed site.
基金Project funded by the National Natural Science Foundation of China, No.48900021
文摘A series of thermal-structural-gneiss domes (briefly TSG domes) are developed in the Chinese Altaides. Sericite-chlorite zone, biotite zone, garnet zone, staurolite zone, kyanite (andalusite)zone, sillimanite- cordierite (sillimanite-garnet)zone, migmatite zone and migmatic granite- gneiss field are developed from the low-grade metamorphic area to the centre of the TSG domes. The succession of the formation and evolution of the progressive metamorphic zone, migmatite zone and migmatic granite-gneiss corresponds to the spatial sequence from the outer part to the centre of the TSG domes. The peak temperature of the metamorphism and granitization increases progressively from 400℃ to 800℃ while the pressure decreases progressively from 1.05 GPa to 0.10 GPa from the biotite zone to the migmatic granite-gneiss field. The metamorphism of the erogenic belt may be described by the pressure-temperature-space-time model (PTst). In the main episode of orogeny, the deep heat flow and structural flow upsurged
