Accurate and effective identification of adverse geology is crucial for safe and efficient tunnel construction.Current methods of identifying adverse geology depend on the experience of geologists and are prone to mis...Accurate and effective identification of adverse geology is crucial for safe and efficient tunnel construction.Current methods of identifying adverse geology depend on the experience of geologists and are prone to misjudgment and omissions.Here,we propose a method for adverse geology identification in tunnels based on mineral anomaly analysis.The method is based on the theory of geoanomaly,and the mineral anomalies are geological markers of the presence of adverse geology.The method uses exploration data analysis(EDA)to calculate mineral anomaly thresholds,then evaluates the mineral anomalies based on the thresholds and identifies adverse geology based on the characteristics of the mineral anomalies.We have established a dynamic expansion process for background samples to achieve the dynamic evaluation of mineral anomalies by adjusting anomaly thresholds.This method has been validated and applied in a tunnel excavated in granite.As shown herein,in the tunnel range of 142+800–142+860,the fault F37 was successfully identified based on an anomalous decrease in the diagenetic minerals plagioclase and hornblende,as well as an anomalous increase in the content of the alteration minerals chlorite,laumonite,and epidote.The proposed method provides a timely warning when a tunnel enters areas affected by adverse geology and identifies whether the tunnel is gradually approaching or moving away from the fault.In addition,the applicability,accuracy,and further improvement of the method are discussed.This method improves our ability to identify adverse geology,from qualitative to quantitative,and can provide reference and guidance for the identification of adverse geology in mining and underground engineering.展开更多
The breakup of weakly-bound projectiles has been shown to significantly influence scattering processes,including elastic scattering.In this context,we revisit the angular distributions(ADs)for the elastic scattering o...The breakup of weakly-bound projectiles has been shown to significantly influence scattering processes,including elastic scattering.In this context,we revisit the angular distributions(ADs)for the elastic scattering of ^(7)Li from ^(118)Sn and ^(120)Sn targets.The study analyzes ^(7)Li+^(118)Sn ADs over the energy range of 18.15-48 MeV and ^(7)Li+^(120)Sn ADs from 20 to 44 MeV,utilizing various nuclear interaction models,including the São Paulo potential,CDM3Y6 potential(with and without the rearrangement term),and cluster folding model.The results indicate that the real component of the folded potentials must be scaled down by 40-65%to achieve an accurate fit to the experimental ADs,underscoring the prominent role of ^(7)Li breakup effects.Interestingly,the conventional threshold anomaly observed in reactions involving tightly bound nuclei is not present.Further analysis using the continuum discretized coupled channels(CDCC)approach provides excellent agreement with the data,reinforcing these findings.展开更多
In a previous study [A.H.Al-Ghamdi et al.,JTUSCI 16(2022) 1026],we comprehensively analyzed elastic scattering angular distributions(ADs) for the ^(7)Li+^(^(28))Si system.This analysis aimed to identify the types of t...In a previous study [A.H.Al-Ghamdi et al.,JTUSCI 16(2022) 1026],we comprehensively analyzed elastic scattering angular distributions(ADs) for the ^(7)Li+^(^(28))Si system.This analysis aimed to identify the types of threshold anomaly,specifically normal and breakup,by examining the energy dependence of volume integrals across various interaction potentials.In the present study,we extended this previous research by investigating the effects of^(7)Li breakup into a valence particle(triton) orbiting a core(alpha) in the context of a^(28)Si target,as well as the influence of the^(28)Si(^(7)Li,α)31P triton transfer reaction on the elastic ADs of the^(7)Li+^(28)Si system.The results demonstrate the significance of coupling to the^(7)Li breakup channel and its subsequent impact on the elastic scattering channel.This strong coupling generates a dynamic polarization potential(DPP),leading to a reduction in potential strengths.A semi-microscopic DPP approach was used to model this effect,employing the continuum discretized coupled channels(CDCC) method.An effective potential(Ueff),considered as the sum of cluster folding and dynamic polarization potentials,was generated using the trivially equivalent local potential(TELP) approach and successfully employed to reproduce the^(7)Li+^(28)Si AD data.Fu rthermore,the analysis was broadened to assess the effect of the triton stripping reaction,^(28)Si(^(7)Li,α)31P,on the elastic ^(7)Li+^(28)Si scattering.展开更多
基金financial support from the National Natural Science Foundation of China(52022053 and 52009073)the Natural Science Foundation of Shandong Province(ZR201910270116)。
文摘Accurate and effective identification of adverse geology is crucial for safe and efficient tunnel construction.Current methods of identifying adverse geology depend on the experience of geologists and are prone to misjudgment and omissions.Here,we propose a method for adverse geology identification in tunnels based on mineral anomaly analysis.The method is based on the theory of geoanomaly,and the mineral anomalies are geological markers of the presence of adverse geology.The method uses exploration data analysis(EDA)to calculate mineral anomaly thresholds,then evaluates the mineral anomalies based on the thresholds and identifies adverse geology based on the characteristics of the mineral anomalies.We have established a dynamic expansion process for background samples to achieve the dynamic evaluation of mineral anomalies by adjusting anomaly thresholds.This method has been validated and applied in a tunnel excavated in granite.As shown herein,in the tunnel range of 142+800–142+860,the fault F37 was successfully identified based on an anomalous decrease in the diagenetic minerals plagioclase and hornblende,as well as an anomalous increase in the content of the alteration minerals chlorite,laumonite,and epidote.The proposed method provides a timely warning when a tunnel enters areas affected by adverse geology and identifies whether the tunnel is gradually approaching or moving away from the fault.In addition,the applicability,accuracy,and further improvement of the method are discussed.This method improves our ability to identify adverse geology,from qualitative to quantitative,and can provide reference and guidance for the identification of adverse geology in mining and underground engineering.
基金the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan(AP26194167)。
文摘The breakup of weakly-bound projectiles has been shown to significantly influence scattering processes,including elastic scattering.In this context,we revisit the angular distributions(ADs)for the elastic scattering of ^(7)Li from ^(118)Sn and ^(120)Sn targets.The study analyzes ^(7)Li+^(118)Sn ADs over the energy range of 18.15-48 MeV and ^(7)Li+^(120)Sn ADs from 20 to 44 MeV,utilizing various nuclear interaction models,including the São Paulo potential,CDM3Y6 potential(with and without the rearrangement term),and cluster folding model.The results indicate that the real component of the folded potentials must be scaled down by 40-65%to achieve an accurate fit to the experimental ADs,underscoring the prominent role of ^(7)Li breakup effects.Interestingly,the conventional threshold anomaly observed in reactions involving tightly bound nuclei is not present.Further analysis using the continuum discretized coupled channels(CDCC)approach provides excellent agreement with the data,reinforcing these findings.
基金Funded by the University of Jeddah, Saudi Arabia (UJ-24-DR-3076-1)。
文摘In a previous study [A.H.Al-Ghamdi et al.,JTUSCI 16(2022) 1026],we comprehensively analyzed elastic scattering angular distributions(ADs) for the ^(7)Li+^(^(28))Si system.This analysis aimed to identify the types of threshold anomaly,specifically normal and breakup,by examining the energy dependence of volume integrals across various interaction potentials.In the present study,we extended this previous research by investigating the effects of^(7)Li breakup into a valence particle(triton) orbiting a core(alpha) in the context of a^(28)Si target,as well as the influence of the^(28)Si(^(7)Li,α)31P triton transfer reaction on the elastic ADs of the^(7)Li+^(28)Si system.The results demonstrate the significance of coupling to the^(7)Li breakup channel and its subsequent impact on the elastic scattering channel.This strong coupling generates a dynamic polarization potential(DPP),leading to a reduction in potential strengths.A semi-microscopic DPP approach was used to model this effect,employing the continuum discretized coupled channels(CDCC) method.An effective potential(Ueff),considered as the sum of cluster folding and dynamic polarization potentials,was generated using the trivially equivalent local potential(TELP) approach and successfully employed to reproduce the^(7)Li+^(28)Si AD data.Fu rthermore,the analysis was broadened to assess the effect of the triton stripping reaction,^(28)Si(^(7)Li,α)31P,on the elastic ^(7)Li+^(28)Si scattering.
