In order to capture the mechanism of roadway instability in deep mines, a new approach of Physically Finite Elemental Slab Assemblage (PFESA) is proposed in order to construct a large-scale physical model simulating t...In order to capture the mechanism of roadway instability in deep mines, a new approach of Physically Finite Elemental Slab Assemblage (PFESA) is proposed in order to construct a large-scale physical model simulating the geologically horizontal strata. We carried out physical modeling on the deformation and failure processes of roadways subjected to a plane loading scheme. Our laboratory tests were based on work which incorporated infrared (IR) detection, IR radiation temperature (IRT) statistics, image feature extraction and 2D Fourier transformation, from resulting thermographies. The IRT characterizes the mechanical responses from the roadway after loading with two stages, i.e., IRT evolving at higher levels corresponded to shallow mining (≤500 m) during which the roadway deformed gradually (referred to as the "steady deformation stage"); IRT evolving in a quasi-cyclical manner with multiple peaks corresponded to deep mining (800–2600 m), in which the failure mode for the roadway are dominated by breakage and collapse (called the "unsteady deformation stage"). The IR images and 2D Fourier spectra illustrate detailed information in terms of initiation, nucleation and coalescence of the damage to rock masses and the eventual failure of roadways subject to external loading.展开更多
REVO?is a dynamic measuring head and probe system,which is designed and applied in orthogonal coordinatemeasuring machines(CMMs)to maximize measurement throughput whilst maintaining high system accuracy.A calibration ...REVO?is a dynamic measuring head and probe system,which is designed and applied in orthogonal coordinatemeasuring machines(CMMs)to maximize measurement throughput whilst maintaining high system accuracy.A calibration approachto the stylus deformation of REVO head is proposed and the scale value of each CMM axis is separated from the limiteddata returned from the measuring system according to the application of REVO head in non-orthogonal CMM.Experimentsshow that the calibration method presented and extraction of scale value are of effectiveness and correctness.Results demonstratethat the maximum measurement error has decreased from0.2021mm to0.0009mm and the variation of scale value ofeach CMM axis is two orders lower after the stylus deformation is compensated.展开更多
基金Projects 2006CB202200 supported by the Special Funds for the Major State Basic Research ProjectIRT0656 by the Innovative Team Development Project of the State Educational Ministry of China
文摘In order to capture the mechanism of roadway instability in deep mines, a new approach of Physically Finite Elemental Slab Assemblage (PFESA) is proposed in order to construct a large-scale physical model simulating the geologically horizontal strata. We carried out physical modeling on the deformation and failure processes of roadways subjected to a plane loading scheme. Our laboratory tests were based on work which incorporated infrared (IR) detection, IR radiation temperature (IRT) statistics, image feature extraction and 2D Fourier transformation, from resulting thermographies. The IRT characterizes the mechanical responses from the roadway after loading with two stages, i.e., IRT evolving at higher levels corresponded to shallow mining (≤500 m) during which the roadway deformed gradually (referred to as the "steady deformation stage"); IRT evolving in a quasi-cyclical manner with multiple peaks corresponded to deep mining (800–2600 m), in which the failure mode for the roadway are dominated by breakage and collapse (called the "unsteady deformation stage"). The IR images and 2D Fourier spectra illustrate detailed information in terms of initiation, nucleation and coalescence of the damage to rock masses and the eventual failure of roadways subject to external loading.
基金National Natural Science Foundation of China(No.51375338)
文摘REVO?is a dynamic measuring head and probe system,which is designed and applied in orthogonal coordinatemeasuring machines(CMMs)to maximize measurement throughput whilst maintaining high system accuracy.A calibration approachto the stylus deformation of REVO head is proposed and the scale value of each CMM axis is separated from the limiteddata returned from the measuring system according to the application of REVO head in non-orthogonal CMM.Experimentsshow that the calibration method presented and extraction of scale value are of effectiveness and correctness.Results demonstratethat the maximum measurement error has decreased from0.2021mm to0.0009mm and the variation of scale value ofeach CMM axis is two orders lower after the stylus deformation is compensated.
