Analyzing the mass of behind-armor debris (BAD) generated by Rolled Homogeneous Armor (RHA) subjected to normal penetration of variable cross-section Explosively Formed Projectile (EFP) is the purpose of this paper. S...Analyzing the mass of behind-armor debris (BAD) generated by Rolled Homogeneous Armor (RHA) subjected to normal penetration of variable cross-section Explosively Formed Projectile (EFP) is the purpose of this paper. So theoretical analysis, numerical simulation and experimental data are combined to analyze the influence of variable cross-section characteristic on the time history of crater radius. Moreover the relationships between time history of crater radius (as well as mass of BAD) and the thickness of RHA (from 30mm to 70 mm) and the impact velocity of EFP (1650 m/s to 1860 m/s) are also investigated. The results indicate that: 1) being compared to the variable cross-section characteristic is ignored, the theoretical time history of crater radius is in better agreement with the simulation results when the variable cross-section characteristic is considered;2) being compared to the other three conditions of plug, the theoretical mass of BAD is in the best agreement with the simulation results when the shape of plug is frustum of a cone and the angle between generatrix and bottom is 45- and the axial length of mushroom is considered.展开更多
The problem of left-behind children appears under the background of China’s industrialization,urbanization and modernization with the deepening of its reform and opening up. From 1980s,literature began to give attent...The problem of left-behind children appears under the background of China’s industrialization,urbanization and modernization with the deepening of its reform and opening up. From 1980s,literature began to give attention to this special phenomenon.Many writers wrote about children’s psychological trauma in alienated families and social environment,and also gave suggestions on the healing of left-behind children’ psychological trauma in their works. This paper argues that the weakening of family education,the deficiency of schooling and the low social coordination are essential factors that lead to the psychological trauma of left-behind children in rural China. Joint effort from family,school and society contribute to the healing of the trauma,among which,love,writings and speeches are effective ways.展开更多
盾构施工过程中产生的大量渣土不仅污染环境,而且会增加运输和处置成本。为解决这一问题,以南京地铁6号线某区间工程为依托,提出将盾构开挖排放的粉质黏土层渣土回收再利用于壁后注浆的技术方法。通过室内试验、SPSS(statistical packag...盾构施工过程中产生的大量渣土不仅污染环境,而且会增加运输和处置成本。为解决这一问题,以南京地铁6号线某区间工程为依托,提出将盾构开挖排放的粉质黏土层渣土回收再利用于壁后注浆的技术方法。通过室内试验、SPSS(statistical package for the social sciences)多元非线性回归分析及多目标规划优化方法,研究渣土浆液性能随水灰比、硬化剂A和硬化剂B掺比(与水泥质量之比)的变化规律,并确定渣土浆液性能与成本的最优配比。研究主要结论为:1)TW-G系列产品适用于高含泥量浆液,其中硬化剂A具有缓凝和减水作用,硬化剂B具有促凝作用。2)多目标规划优化结果显示,性能最优配比为水灰比0.75,硬化剂A掺比为0.86%,硬化剂B掺比为12.95%;成本最优配比为水灰比0.84,硬化剂A掺比为3.66%,硬化剂B掺比为2.91%。3)现场实践表明,相比于普通单液硬性浆,渣土浆液性能更佳,用于盾构壁后注浆后地表沉降控制在12 mm以内,管片上浮控制在25 mm以内,且能够减少渣土外运10%以上,成本降低35%左右。展开更多
基金financially supported by the National Natural Science Foundation of China(Grant No.11372136)
文摘Analyzing the mass of behind-armor debris (BAD) generated by Rolled Homogeneous Armor (RHA) subjected to normal penetration of variable cross-section Explosively Formed Projectile (EFP) is the purpose of this paper. So theoretical analysis, numerical simulation and experimental data are combined to analyze the influence of variable cross-section characteristic on the time history of crater radius. Moreover the relationships between time history of crater radius (as well as mass of BAD) and the thickness of RHA (from 30mm to 70 mm) and the impact velocity of EFP (1650 m/s to 1860 m/s) are also investigated. The results indicate that: 1) being compared to the variable cross-section characteristic is ignored, the theoretical time history of crater radius is in better agreement with the simulation results when the variable cross-section characteristic is considered;2) being compared to the other three conditions of plug, the theoretical mass of BAD is in the best agreement with the simulation results when the shape of plug is frustum of a cone and the angle between generatrix and bottom is 45- and the axial length of mushroom is considered.
基金Social Science Achievement Appraisal Committee Project in Hunan Province:The Revelation of Morrison’s Traumatic Thought to the Psychological Trauma’s Healing of Modern Left-behind Children(XSP17YBZZ001)Scientific Research Project of Education Department of Hunan Province:A study of Female Trauma in Toni Morrison’s novels(16C0237)
文摘The problem of left-behind children appears under the background of China’s industrialization,urbanization and modernization with the deepening of its reform and opening up. From 1980s,literature began to give attention to this special phenomenon.Many writers wrote about children’s psychological trauma in alienated families and social environment,and also gave suggestions on the healing of left-behind children’ psychological trauma in their works. This paper argues that the weakening of family education,the deficiency of schooling and the low social coordination are essential factors that lead to the psychological trauma of left-behind children in rural China. Joint effort from family,school and society contribute to the healing of the trauma,among which,love,writings and speeches are effective ways.
文摘盾构施工过程中产生的大量渣土不仅污染环境,而且会增加运输和处置成本。为解决这一问题,以南京地铁6号线某区间工程为依托,提出将盾构开挖排放的粉质黏土层渣土回收再利用于壁后注浆的技术方法。通过室内试验、SPSS(statistical package for the social sciences)多元非线性回归分析及多目标规划优化方法,研究渣土浆液性能随水灰比、硬化剂A和硬化剂B掺比(与水泥质量之比)的变化规律,并确定渣土浆液性能与成本的最优配比。研究主要结论为:1)TW-G系列产品适用于高含泥量浆液,其中硬化剂A具有缓凝和减水作用,硬化剂B具有促凝作用。2)多目标规划优化结果显示,性能最优配比为水灰比0.75,硬化剂A掺比为0.86%,硬化剂B掺比为12.95%;成本最优配比为水灰比0.84,硬化剂A掺比为3.66%,硬化剂B掺比为2.91%。3)现场实践表明,相比于普通单液硬性浆,渣土浆液性能更佳,用于盾构壁后注浆后地表沉降控制在12 mm以内,管片上浮控制在25 mm以内,且能够减少渣土外运10%以上,成本降低35%左右。
