As2S3 and As2Se3 chalcogenide 3-bridges suspended-core fibers（SCFs） are designed with shifted zero-dispersion wavelengths（ZDWs） at around 1.5 μm, 2 μm, and 2.8 μm, respectively. A generalized nonlinear Schrodin...As2S3 and As2Se3 chalcogenide 3-bridges suspended-core fibers（SCFs） are designed with shifted zero-dispersion wavelengths（ZDWs） at around 1.5 μm, 2 μm, and 2.8 μm, respectively. A generalized nonlinear Schrodinger equation is used to numerically compare supercontinuum（SC） generation in these SCFs pumped at an anomalous dispersion region nearby their ZDWs. Evolutions of the long-wavelength edge（LWE）, the power proportion in the long-wavelength region（PPL）, and spectral flatness（SF） are calculated and analyzed. Meanwhile, the optimal pump parameters and fiber length are given with LWE, PPL, and SF taken into account. For As2S3 SCFs, SC from a 14 mm-long fiber with a ZDW of 2825 nm pumped at 2870 nm can achieve the longest LWE of - 13 μm and PPL up to ～72%. For As2Se3 SCFs, the LWE of 15.5 μm and the highest PPL of ～ 87% can be achieved in a 10 mm-long fiber with ZDW of 1982 nm pumped at 2000 nm. Although the As2Se3 SCFs can achieve much longer LWE than the As2S3 SCFs, the core diameter of As2Se3 SCFs will be much smaller to obtain a similar ZDW, leading to lower damage threshold and output power. Finally, the optimal parameters for generating SC spanning over different mid-IR windows are given.展开更多
This paper focuses on the analytical derivation and the numerical simulation analyses to predict the interaction influences between a landslide and a new tunnel in mountain areas. Based on the slip-line theory, the di...This paper focuses on the analytical derivation and the numerical simulation analyses to predict the interaction influences between a landslide and a new tunnel in mountain areas. Based on the slip-line theory, the disturbance range induced by tunneling and the minimum safe distance between the tunnel vault and the sliding belt are obtained in consideration of the mechanical analyses of relaxed rocks over the tunnel opening. The influence factors for the minimum safe crossing distance are conducted,including the tunnel radius, the friction angle of surrounding rocks, the inclination angle of sliding belt,and the friction coefficient of surrounding rocks. Secondly, taking account of the compressive zone and relaxed rocks caused by tunneling, the Sarma method is employed to calculate the safety factor of landslide. Finally, the analytical solutions for interaction between the tunnel and the landslide are compared with a series of numerical simulations, considering the cases for different perpendicular distances between the tunnel vault and the sliding belt. Resultsshow that the distance between the tunnel vault and the slip zone has significant influence on the rock stress and strain. For the case of the minimum crossing distance, a plastic zone in the landslide traversed by tunneling would be formed with rather large range, which seriously threatens the stability of landslide. This work demonstrates that the minimum safe crossing distance obtained from numerical simulation is in a good agreement with that calculated by the proposed analytical solutions.展开更多
基金Project supported by the National Nature Science Foundation of China(Grant Nos.61435003,61377042,61505024,and 61421002)Open Fund of State Key Laboratory of Advanced Optical Communication Systems and Networks,China(Grant No.2015GZKF004)+1 种基金Open Found of Key Laboratory of Specialty Fiber Optics and Optical Access Networks,Shanghai University,China(Grant No.SKLSFO2014-07)Open Fund of Science and Technology on Solid-State Laser Laboratory,China(Grant No.H04010501W2015000604)
文摘As2S3 and As2Se3 chalcogenide 3-bridges suspended-core fibers（SCFs） are designed with shifted zero-dispersion wavelengths（ZDWs） at around 1.5 μm, 2 μm, and 2.8 μm, respectively. A generalized nonlinear Schrodinger equation is used to numerically compare supercontinuum（SC） generation in these SCFs pumped at an anomalous dispersion region nearby their ZDWs. Evolutions of the long-wavelength edge（LWE）, the power proportion in the long-wavelength region（PPL）, and spectral flatness（SF） are calculated and analyzed. Meanwhile, the optimal pump parameters and fiber length are given with LWE, PPL, and SF taken into account. For As2S3 SCFs, SC from a 14 mm-long fiber with a ZDW of 2825 nm pumped at 2870 nm can achieve the longest LWE of - 13 μm and PPL up to ～72%. For As2Se3 SCFs, the LWE of 15.5 μm and the highest PPL of ～ 87% can be achieved in a 10 mm-long fiber with ZDW of 1982 nm pumped at 2000 nm. Although the As2Se3 SCFs can achieve much longer LWE than the As2S3 SCFs, the core diameter of As2Se3 SCFs will be much smaller to obtain a similar ZDW, leading to lower damage threshold and output power. Finally, the optimal parameters for generating SC spanning over different mid-IR windows are given.
基金financial support provided by Natural Science Foundation of China (Grant No. 51008188)by Shanghai Natural Science Foundation (Grant No. 15ZR1429400)+2 种基金by Open Project Program of State Key Laboratory Breeding Base of Mountain Bridge and Tunnel Engineering (Grant No. CQSLBF-Y15-1)by Open Project Program of State Key Laboratory of Geohazard Prevention and Geoenvironment Protection (Grant No. SKLGP2015K015)by the Open Project Program of Key Laboratory of Geohazard Prevention of Hilly Mountains, Ministry of Land and Resources (Grant No. 2015k005)
文摘This paper focuses on the analytical derivation and the numerical simulation analyses to predict the interaction influences between a landslide and a new tunnel in mountain areas. Based on the slip-line theory, the disturbance range induced by tunneling and the minimum safe distance between the tunnel vault and the sliding belt are obtained in consideration of the mechanical analyses of relaxed rocks over the tunnel opening. The influence factors for the minimum safe crossing distance are conducted,including the tunnel radius, the friction angle of surrounding rocks, the inclination angle of sliding belt,and the friction coefficient of surrounding rocks. Secondly, taking account of the compressive zone and relaxed rocks caused by tunneling, the Sarma method is employed to calculate the safety factor of landslide. Finally, the analytical solutions for interaction between the tunnel and the landslide are compared with a series of numerical simulations, considering the cases for different perpendicular distances between the tunnel vault and the sliding belt. Resultsshow that the distance between the tunnel vault and the slip zone has significant influence on the rock stress and strain. For the case of the minimum crossing distance, a plastic zone in the landslide traversed by tunneling would be formed with rather large range, which seriously threatens the stability of landslide. This work demonstrates that the minimum safe crossing distance obtained from numerical simulation is in a good agreement with that calculated by the proposed analytical solutions.
