期刊文献+
共找到3篇文章
< 1 >
每页显示 20 50 100
多层格栅加筋道砟界面联动‒互扰行为
1
作者 苗晨曦 张威 +2 位作者 朱孝振 陈小艺 张军 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第9期1393-1400,共8页
探究多层加筋土体系中筋材‒道砟间合理间距对拉拔抗力的影响。通过改进传统单层格栅‒道砟拉拔数值试验模型,实现了多层格栅等位移幅值下的同步拉拔的离散元模拟。数值模型采用刚性颗粒簇模拟道砟颗粒非球型特征,并运用黏结颗粒串模拟受... 探究多层加筋土体系中筋材‒道砟间合理间距对拉拔抗力的影响。通过改进传统单层格栅‒道砟拉拔数值试验模型,实现了多层格栅等位移幅值下的同步拉拔的离散元模拟。数值模型采用刚性颗粒簇模拟道砟颗粒非球型特征,并运用黏结颗粒串模拟受力均匀的三向土工格栅,同时考虑了道砟颗粒间的嵌固效应和土工格栅的拉伸特性。以平均拉拔力、特定层位处界面强度与筋材应变为指标,科学识别多层格栅加筋道砟界面联动行为,并从颗粒尺度系统揭示了多层加筋体系层间互扰机制。结果表明,多层格栅的拉拔力和增长速率小于单层格栅,尤其在高法向应力下差异更明显,且存在不均匀性。随着加筋层数增加,筋材抗力差异显著,同时摩擦耗能增大。层间颗粒位移存在叠合,导致筋材宏观力学响应减弱,其内在原因是颗粒力链发育不够充分。法向接触力分析结果进一步表明,多层格栅加筋体系下的层间互扰可能导致法向接触力分布的不稳定性。 展开更多
关键词 土工格栅 道砟 多层拉拔试验 互扰机制
下载PDF
Criteria for intermittent and continuous disturbance transition of ERA interaction with shaped charge jet
2
作者 Li Rujiang Shen Zhaowu 《Engineering Sciences》 EI 2008年第3期69-71,89,共4页
There are two interaction mechanisms between shaped charge jet and thin flying plate driven by explosion, that is, the intermittent and continuous disturbance. Determination of the transition criteria for the intermit... There are two interaction mechanisms between shaped charge jet and thin flying plate driven by explosion, that is, the intermittent and continuous disturbance. Determination of the transition criteria for the intermittent and continuous disturbance is of importance for the penetration calculation of the escaping jet and the design of ERA(explosive reactive armour). In this paper a new criteria was presented based on the analysis of interaction process, and the effects of NATO angle and thickness of flying plate on the disturbance frequency were discussed. It is shown that the critical shaped charge jet velocity increases with the plate thickness and NATO angle, especially increases drastically between 45° and 60°. 展开更多
关键词 explosion mechanics intermittent disturbance continuous disturbance explosive reactive armor shaped charge jet
下载PDF
Nonlinear interaction mechanisms of disturbances in supersonic flat-plate boundary layers 被引量:3
3
作者 YU Min LUO JiSheng 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2014年第11期2141-2151,共11页
Due to the complexity of compressible flows,nonlinear hydrodynamic stability theories in supersonic boundary layers are not sufficient.In order to reveal the nonlinear interaction mechanisms of the rapidly amplified 3... Due to the complexity of compressible flows,nonlinear hydrodynamic stability theories in supersonic boundary layers are not sufficient.In order to reveal the nonlinear interaction mechanisms of the rapidly amplified 3-D disturbances in supersonic boundary layers at high Mach numbers,the nonlinear evolutions of different disturbances in flat-plate boundary layers at Mach number 4.5,6 and 8 are analyzed by numerical simulations.It can be concluded that the 3-D disturbances are amplified rapidly when the amplitude of the 2-D disturbance reaches a certain level.The most rapidly amplified 3-D disturbances are Klebanoff type(K-type)disturbances which have the same frequency as the 2-D disturbance.Among these K-type 3-D disturbances,the disturbances located at the junction of upper branch and lower branch of the neutral curve are amplified higher.Through analyzing the relationship between the amplification rate and the spanwise wavenumber of the 3-D disturbances at different evolution stages,the mechanism of the spanwise wavenumber selectivity of K-type 3-D disturbances in the presence of a finite amplitude 2-D disturbance is explained. 展开更多
关键词 disturbance supersonic junction branch introducing selectivity compressible hydrodynamic explained infinity
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部