Utilizing the acoustic emission(AE) technique, an experimental investigation into the damage evolution for steel strand under axial tension was described. The damage evolution model for steel stand relating the damage...Utilizing the acoustic emission(AE) technique, an experimental investigation into the damage evolution for steel strand under axial tension was described. The damage evolution model for steel stand relating the damage evolution to acoustic emission parameters was proposed by incorporating the AE rate process theory. The AE monitoring results indicate that damages occur in both elastic and plastic phases of steel strand. In elastic phase, AE signals are mainly sent out from the micro damage due to the surface friction among the wires of steel strand, while in plastic phase, AE signals emitted from the plastic deformation of wires. In addition, the AE cumulative parameters curves closely resemble the loading curve. The AE cumulative parameters curves can well describe the damage evolution process including the damage occurrence and damage development for steel strands. It is concluded that the AE technique is an effective and useful nondestructive technique for evaluating the damage characteristics of steel strand.展开更多
Rock fracture warning is one of the significant challenges in rock mechanics.Many true triaxial and synchronous acoustic emission(AE)tests were conducted on granite samples.The investigation focused on the characteris...Rock fracture warning is one of the significant challenges in rock mechanics.Many true triaxial and synchronous acoustic emission(AE)tests were conducted on granite samples.The investigation focused on the characteristics of AE signals preceding granite fracture,based on the critical slowing down(CSD)theory.The granite undergoes a transition from the stable phase to the fracture phase and exhibits a clear CSD phenomenon,characterized by a pronounced increase in variance and autocorrelation coefficient.The variance mutation points were found to be more identifiable and suitable as the primary criterion for predicting precursor information related to granite fracture,compared to the autocorrelation coefficient.It is noteworthy to emphasize that the CSD factor holds greater potential in elucidating the underlying mechanisms responsible for the critical transition of granite fracture,in comparison to the AE timing parameters.Furthermore,a novel multi-parameter collaborative prediction method for rock fracture was developed by comprehensively analyzing predictive information,including abnormal variation modes and the CSD factor of AE characteristic parameters.This method enhances the understanding and prediction of rock fracture-related geohazards.展开更多
在双碳目标背景下,针对园区综合能源系统(park integrated energy system,PIES)的低碳优化已有诸多研究,但现有研究较少从碳流层面提出提升碳效的低碳优化策略。为此,文中基于云平台提出考虑碳流优化的PIES低碳经济运行策略。首先,构建...在双碳目标背景下,针对园区综合能源系统(park integrated energy system,PIES)的低碳优化已有诸多研究,但现有研究较少从碳流层面提出提升碳效的低碳优化策略。为此,文中基于云平台提出考虑碳流优化的PIES低碳经济运行策略。首先,构建一种双层协同优化架构,在上层云平台设计碳流优化模块,为下层PIES提供优化建议,下层系统对自身用能计划进行修正,实现协同优化。其次,建立负荷碳势指标测算PIES碳流水平,通过云平台引导PIES降低负荷碳势从而提升系统碳效,并且进一步在云平台设计考虑碳效的纳什议价模块,以提升多主体交易中参与方的碳收益。然后,采用目标级联分析法对双层模型进行求解。最后,通过仿真验证考虑碳流优化的运行策略不仅可以提升综合能源系统经济收益,还能减少碳排,提升碳效,同时在促进PIES间能源交易的过程中提高碳收益。展开更多
基金Projects(51308073,51378081)supported by the National Natural Science Foundation of ChinaProject(20124316120002)supported by PhD Programs Foundation of Ministry of Education of China+1 种基金Project(12KB02)supported by the Key Laboratory for Safety Control of Bridge Engineering of Ministry of Education of ChinaProject(14JJ3087)supported by the Science Foundation of Hunan Province,China
文摘Utilizing the acoustic emission(AE) technique, an experimental investigation into the damage evolution for steel strand under axial tension was described. The damage evolution model for steel stand relating the damage evolution to acoustic emission parameters was proposed by incorporating the AE rate process theory. The AE monitoring results indicate that damages occur in both elastic and plastic phases of steel strand. In elastic phase, AE signals are mainly sent out from the micro damage due to the surface friction among the wires of steel strand, while in plastic phase, AE signals emitted from the plastic deformation of wires. In addition, the AE cumulative parameters curves closely resemble the loading curve. The AE cumulative parameters curves can well describe the damage evolution process including the damage occurrence and damage development for steel strands. It is concluded that the AE technique is an effective and useful nondestructive technique for evaluating the damage characteristics of steel strand.
基金Project(52074294)supported by the National Natural Science Foundation of ChinaProject(2022YJSNY16)supported by the Fundamental Research Funds for the Central Universities,China。
文摘Rock fracture warning is one of the significant challenges in rock mechanics.Many true triaxial and synchronous acoustic emission(AE)tests were conducted on granite samples.The investigation focused on the characteristics of AE signals preceding granite fracture,based on the critical slowing down(CSD)theory.The granite undergoes a transition from the stable phase to the fracture phase and exhibits a clear CSD phenomenon,characterized by a pronounced increase in variance and autocorrelation coefficient.The variance mutation points were found to be more identifiable and suitable as the primary criterion for predicting precursor information related to granite fracture,compared to the autocorrelation coefficient.It is noteworthy to emphasize that the CSD factor holds greater potential in elucidating the underlying mechanisms responsible for the critical transition of granite fracture,in comparison to the AE timing parameters.Furthermore,a novel multi-parameter collaborative prediction method for rock fracture was developed by comprehensively analyzing predictive information,including abnormal variation modes and the CSD factor of AE characteristic parameters.This method enhances the understanding and prediction of rock fracture-related geohazards.
文摘在双碳目标背景下,针对园区综合能源系统(park integrated energy system,PIES)的低碳优化已有诸多研究,但现有研究较少从碳流层面提出提升碳效的低碳优化策略。为此,文中基于云平台提出考虑碳流优化的PIES低碳经济运行策略。首先,构建一种双层协同优化架构,在上层云平台设计碳流优化模块,为下层PIES提供优化建议,下层系统对自身用能计划进行修正,实现协同优化。其次,建立负荷碳势指标测算PIES碳流水平,通过云平台引导PIES降低负荷碳势从而提升系统碳效,并且进一步在云平台设计考虑碳效的纳什议价模块,以提升多主体交易中参与方的碳收益。然后,采用目标级联分析法对双层模型进行求解。最后,通过仿真验证考虑碳流优化的运行策略不仅可以提升综合能源系统经济收益,还能减少碳排,提升碳效,同时在促进PIES间能源交易的过程中提高碳收益。
