Due to the long-term plate tectonic movements in southwestern China,the in-situ stress field in deep formations is complex.When passing through deep soft-rock mass under non-hydrostatic high in-situ stress field,tunne...Due to the long-term plate tectonic movements in southwestern China,the in-situ stress field in deep formations is complex.When passing through deep soft-rock mass under non-hydrostatic high in-situ stress field,tunnels will suffer serious asymmetric deformation.There is no available support design method for tunnels under such a situation in existing studies to clarify the support time and support stiffness.This study first analyzed the mechanical behavior of tunnels in non-hydrostatic in-situ stress field and derived the theoretical equations of the ground squeezing curve(GSC)and ground loosening curve(GLC).Then,based on the convergence confinement theory,the support design method of deep soft-rock tunnels under non-hydrostatic high in-situ stress field was established considering both squeezing and loosening pressures.In addition,this method can provide the clear support time and support stiffness of the second layer of initial support.The proposed design method was applied to the Wanhe tunnel of the China-Laos railway in China.Monitoring data indicated that the optimal support scheme had a good effect on controlling the tunnel deformation in non-hydrostatic high in-situ stress field.Field applications showed that the secondary lining could be constructed properly.展开更多
The surrounding rock is prone to large-scale loosening and failure after the excavation of shallow large-span caverns because of the thin overlying strata and large cross-section span.The rational design of bolt suppo...The surrounding rock is prone to large-scale loosening and failure after the excavation of shallow large-span caverns because of the thin overlying strata and large cross-section span.The rational design of bolt support is very important to the safety control of surrounding rock as a common support means.The control mechanism and design method of bolt support for shallow-buried large-span caverns is carried out.The calculation method of bolt prestress and length based on arched failure and collapsed failure mode is established.The influence mechanism of different influencing factors on the bolt prestress and length is clarified.At the same time,the constant resistance energy-absorbing bolt with high strength and high toughness is developed,and the comparative test of mechanical properties is carried out.On this basis,the design method of high prestressed bolt support for shallow-buried large-span caverns is put forward,and the field test is carried out in Qingdao metro station in China.The monitoring results show that the maximum roof settlement is 6.8 mm after the new design method is adopted,and the effective control of the shallow-buried large-span caverns is realized.The research results can provide theoretical and technical support for the safety control of shallow-buried large-span caverns.展开更多
Backfill hydraulic support is the key equipment in achieving coal mining and solid backfilling simultaneously in solid backfill mining technology.Based on the summary and analysis of main types,basic structural proper...Backfill hydraulic support is the key equipment in achieving coal mining and solid backfilling simultaneously in solid backfill mining technology.Based on the summary and analysis of main types,basic structural properties and filed application of backfill hydraulic support,this work has firstly proposed the basic principle of backfill hydraulic support optimization design and provided the method of optimal design of key structural components,like four-bar linkage,rear canopy and tamping structure;the method is further elaborated as changing hinging position of upper bar to optimize four-bar linkage,by lengthening or shortening the rear canopy to optimize length ratio of canopy;and by changing length and hinging position of tamping structure as well as suspension height of backfill scrape conveyor to realize optimization of tamping structure.On this basis,the process of optimal design of backfill hydraulic support is built.The optimal design case of ZC5200/14.5/30 six columns-four bar linkage used in 7203 W workface of Zhaizhen Coal Mine shows that the backfill properties like horizontal roof gap,vertical horizontal gap,tamping angle and tamping head gap are improved obviously through optimizing four-bar linkage,canopy length and tamping structure according to the optimal design method proposed in this work.展开更多
This paper addresses the question of how to support the designer with appropriate knowledge during conceptual design. It begins with a discussion of knowledge-based support for design and is followed by a scenario acc...This paper addresses the question of how to support the designer with appropriate knowledge during conceptual design. It begins with a discussion of knowledge-based support for design and is followed by a scenario account of the use of a Knowledge Support System. A system is described that demonstrates interaction with different forms of knowledge in concept vehicle design.It supports the creation of new designs by way of a solution generation and evaluation process that relies upon co-operation between the designer and the knowledge system. The results of user evaluation gave rise to a current research agenda which addresses the requirements of a multi-user platform for a design knowledge support environment for collaborative team work.展开更多
Feedback mechanism is a specific feature of control systems, however, the similarity has been found in decision support systems. Just because of this, the DSS can provide a flexible learning and thinking environment, ...Feedback mechanism is a specific feature of control systems, however, the similarity has been found in decision support systems. Just because of this, the DSS can provide a flexible learning and thinking environment, and help decision maker to solve semistructured and unstructured problems actively and creatively. In this paper, the role and type of the feedback in decision making are discussed from different point of view. This is also true in DSS because it supports decision making. The feedback design, especially the feedback interface design, is described through a case of practice DSS. Based on these points, the feedback mechanism is an important feature of DSS, and it is one of the differences between DSS and MIS.展开更多
During architectural conception phase,building maintenance problematic is mostly a result of the unintentional use of preconceived architectonical solutions rather than a consequence of a specific influence of mainten...During architectural conception phase,building maintenance problematic is mostly a result of the unintentional use of preconceived architectonical solutions rather than a consequence of a specific influence of maintenance requirements.Hardly the architect in the act of design understands the importance of these solutions in the service life span of a building.Being aware of this,is it possible for the architect to be supplied with a decision support system that allows him to consider the implications of building maintenance since the early design phases? Having awareness of this problem and its consequences in the early design phases a research project was started at the Faculty Engineering of the University of Oporto(FEUP),under which the implications of building maintenance in the act of architectural design is studied.This article presents the methodology developed to identify the needs of maintenance of buildings based on a DSS-decision support system that provides simple tools the architect can use in design phase.This methodology is based on decomposition of building parts-Elements Source of Maintenance ESM-,and subsequently,a set of functional requirements that determine the performance regarding building maintenance on account of architectural decisions.Relevant maintenance actions are defined: Inspection,Pro-action,Cleaning,Correction,Replacement,Legal enforcement,Limits of use.One can thus set up a relationship between the act of design and its performance framework based on behavior,intervention and the ownership of the work of architecture.Using a Multicriteria Analysis(MCA) a qualitative evaluation of different options based on maintenance requirements accomplishment.Conclusions on the importance of architectural conception concerning the building maintenance were clearly arrived at and the utility of the developed decision support tool was also highlighted.展开更多
基金Project(52178402)supported by the National Natural Science Foundation of ChinaProject(2021-Key-09)supported by the Science and Technology Research and Development Program Project of China Railway Group LimitedProject(2021zzts0216)supported by the Innovation-Driven Project of Central South University,China。
文摘Due to the long-term plate tectonic movements in southwestern China,the in-situ stress field in deep formations is complex.When passing through deep soft-rock mass under non-hydrostatic high in-situ stress field,tunnels will suffer serious asymmetric deformation.There is no available support design method for tunnels under such a situation in existing studies to clarify the support time and support stiffness.This study first analyzed the mechanical behavior of tunnels in non-hydrostatic in-situ stress field and derived the theoretical equations of the ground squeezing curve(GSC)and ground loosening curve(GLC).Then,based on the convergence confinement theory,the support design method of deep soft-rock tunnels under non-hydrostatic high in-situ stress field was established considering both squeezing and loosening pressures.In addition,this method can provide the clear support time and support stiffness of the second layer of initial support.The proposed design method was applied to the Wanhe tunnel of the China-Laos railway in China.Monitoring data indicated that the optimal support scheme had a good effect on controlling the tunnel deformation in non-hydrostatic high in-situ stress field.Field applications showed that the secondary lining could be constructed properly.
基金Project(2023YFC3805700) supported by the National Key Research and Development Program of ChinaProjects(42477166,42277174) supported by the National Natural Science Foundation of China+2 种基金Project(2024JCCXSB01) supported by the Fundamental Research Funds for the Central Universities,ChinaProject(KFJJ24-01M) supported by the State Key Laboratory of Explosion Science and Safety Protection,Beijing Institute of Technology,ChinaProject(HLCX-2024-04) supported by the Open Foundation of Collaborative Innovation Center of Green Development and Ecological Restoration of Mineral Resources,China。
文摘The surrounding rock is prone to large-scale loosening and failure after the excavation of shallow large-span caverns because of the thin overlying strata and large cross-section span.The rational design of bolt support is very important to the safety control of surrounding rock as a common support means.The control mechanism and design method of bolt support for shallow-buried large-span caverns is carried out.The calculation method of bolt prestress and length based on arched failure and collapsed failure mode is established.The influence mechanism of different influencing factors on the bolt prestress and length is clarified.At the same time,the constant resistance energy-absorbing bolt with high strength and high toughness is developed,and the comparative test of mechanical properties is carried out.On this basis,the design method of high prestressed bolt support for shallow-buried large-span caverns is put forward,and the field test is carried out in Qingdao metro station in China.The monitoring results show that the maximum roof settlement is 6.8 mm after the new design method is adopted,and the effective control of the shallow-buried large-span caverns is realized.The research results can provide theoretical and technical support for the safety control of shallow-buried large-span caverns.
基金Project(2017QNA21)supported by the Fundamental Research Funds for the Central Universities of ChinaProject supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD),China
文摘Backfill hydraulic support is the key equipment in achieving coal mining and solid backfilling simultaneously in solid backfill mining technology.Based on the summary and analysis of main types,basic structural properties and filed application of backfill hydraulic support,this work has firstly proposed the basic principle of backfill hydraulic support optimization design and provided the method of optimal design of key structural components,like four-bar linkage,rear canopy and tamping structure;the method is further elaborated as changing hinging position of upper bar to optimize four-bar linkage,by lengthening or shortening the rear canopy to optimize length ratio of canopy;and by changing length and hinging position of tamping structure as well as suspension height of backfill scrape conveyor to realize optimization of tamping structure.On this basis,the process of optimal design of backfill hydraulic support is built.The optimal design case of ZC5200/14.5/30 six columns-four bar linkage used in 7203 W workface of Zhaizhen Coal Mine shows that the backfill properties like horizontal roof gap,vertical horizontal gap,tamping angle and tamping head gap are improved obviously through optimizing four-bar linkage,canopy length and tamping structure according to the optimal design method proposed in this work.
文摘This paper addresses the question of how to support the designer with appropriate knowledge during conceptual design. It begins with a discussion of knowledge-based support for design and is followed by a scenario account of the use of a Knowledge Support System. A system is described that demonstrates interaction with different forms of knowledge in concept vehicle design.It supports the creation of new designs by way of a solution generation and evaluation process that relies upon co-operation between the designer and the knowledge system. The results of user evaluation gave rise to a current research agenda which addresses the requirements of a multi-user platform for a design knowledge support environment for collaborative team work.
文摘Feedback mechanism is a specific feature of control systems, however, the similarity has been found in decision support systems. Just because of this, the DSS can provide a flexible learning and thinking environment, and help decision maker to solve semistructured and unstructured problems actively and creatively. In this paper, the role and type of the feedback in decision making are discussed from different point of view. This is also true in DSS because it supports decision making. The feedback design, especially the feedback interface design, is described through a case of practice DSS. Based on these points, the feedback mechanism is an important feature of DSS, and it is one of the differences between DSS and MIS.
文摘During architectural conception phase,building maintenance problematic is mostly a result of the unintentional use of preconceived architectonical solutions rather than a consequence of a specific influence of maintenance requirements.Hardly the architect in the act of design understands the importance of these solutions in the service life span of a building.Being aware of this,is it possible for the architect to be supplied with a decision support system that allows him to consider the implications of building maintenance since the early design phases? Having awareness of this problem and its consequences in the early design phases a research project was started at the Faculty Engineering of the University of Oporto(FEUP),under which the implications of building maintenance in the act of architectural design is studied.This article presents the methodology developed to identify the needs of maintenance of buildings based on a DSS-decision support system that provides simple tools the architect can use in design phase.This methodology is based on decomposition of building parts-Elements Source of Maintenance ESM-,and subsequently,a set of functional requirements that determine the performance regarding building maintenance on account of architectural decisions.Relevant maintenance actions are defined: Inspection,Pro-action,Cleaning,Correction,Replacement,Legal enforcement,Limits of use.One can thus set up a relationship between the act of design and its performance framework based on behavior,intervention and the ownership of the work of architecture.Using a Multicriteria Analysis(MCA) a qualitative evaluation of different options based on maintenance requirements accomplishment.Conclusions on the importance of architectural conception concerning the building maintenance were clearly arrived at and the utility of the developed decision support tool was also highlighted.
