搜索结果: 121-135 共查到“知识库 固体力学”相关记录2082条 . 查询时间(3.203 秒)
CRO试样的疲劳裂纹扩展行为试验方法研究
固体力学 疲劳裂纹扩展 柔度法 CRO试样 5083-H112铝合金 C250马氏体钢
2016/12/8
考虑到如紧凑拉伸和三点弯曲等标准试样的大尺寸要求以及高试验成本等突出问题,该文发展了含外侧径向裂纹C形环小试样(C-ring with an outer radial crack,CRO)的疲劳裂纹扩展行为试验方法。利用有限元分析建立了CRO小试样的高精度应力强度因子算式以及基于柔度法理论的裂纹长度预测公式。采用5083-H112铝合金分别完成了CRO试样和标准CT试样的疲劳裂纹扩展速率试验,获得...
基于应变梯度理论建立了单层石墨烯等效明德林(Mindlin) 板动力学方程,推导了四边简支明德林中厚板自由振动固有频率的解析解. 提出了一种考虑应变梯度的4 节点36 自由度明德林板单元,利用虚功原理建立了单层石墨烯的等效非局部板有限元模型. 通过对石墨烯振动问题的研究,验证了应变梯度有限元计算结果的收敛性. 运用该有限元法研究了尺寸、振动模态阶数以及非局部参数对石墨烯振动特性的影响. 研究表明,...
Ground tilt monitoring at Phlegraean Fields (Italy): a methodological approach
tilt data thermoelastic deformation thermal correction
2015/9/17
Among geodetic methods used for monitoring ground deformation in volcanic areas, tiltmetry represents the
most rapid technique and therefore it is used by almost all the volcanological observatories ...
向心涡轮进气结构的气动性能及损失机理
流动分析 效率 流动损失
2015/9/8
针对某向心涡轮,采用二维流动分析方法设计矩形截面蜗壳,同时采用商用计算流体动力学软件CFX对带蜗壳的向心涡轮流动损失进行数值计算.将计算结果与原型设计中带有集气室的向心涡轮计算结果进行对比.结果表明:蜗壳内流动损失要小于集气室内的流动损失,向心涡轮采用蜗壳后流道内流场有明显改善,效率有所提高.采用设计的矩形截面蜗壳,向心涡轮的功率提高1.7%.通过内部流场的分析,揭示了内部流场结构和损失机理,为向...
结合刚体基本运动分析三刚片体系几何构造
几何构造分析 无穷远瞬铰 刚体运动 结构力学
2016/11/1
为探寻体系几何构造分析技巧,总结了三刚片连接的所有可能形式,在简化模型分析基础上,结合刚体的基本运动特征,针对三刚片连接形式中有无穷远瞬铰出现的特殊情况进行详细分析,获取体系构造分析中的一般规律,为学习体系几何构造分析提供帮助.
索结构因其轻、柔及高强度等特性被作为受拉构件广泛应用于工程领域.一方面,环境载荷激励下索结构产生了复杂的大幅动力响应,给结构带来危害;另一方面,索结构是一个同时含有平方和立方非线性的典型力学系统,具有非常丰富的非线性动力学行为.因此,索动力学的研究受到了工程界和力学界的广泛关注,产生了大量的研究成果.本文尝试从索结构动力学建模、非线性内共振分析、支座运动激励下的索动力学以及复杂环境载荷作用4个方面...
Extended finite element framework for fault rupture dynamics including bulk plasticity
extended finite elements fault rupture dynamics bulk plasticity
2015/7/1
We present an explicit extended finite element framework for fault rupture dynamics accommodating bulk plasticity near the fault. The technique is more robust than the standard split-node method becau...
Mathematical framework for unsaturated flow in the finite deformation range
finite deformation finite element heterogeneity porous media unsaturated soil
2015/7/1
The presence of fluid in the pores of a solid imposes a volume constraint on the deformation of the solid. Finite changes in the pore volume alter the degree of saturation of a porous material, impact...
Discrete micromechanics of elastoplastic crystals in the finite deformation range
Crystal plasticity Finite deformation Micromechanics Stress-point integration Strong discontinuity
2015/7/1
We present a rate-independent crystal plasticity theory in the finite deformation range. The formulation revolves around theory of distribution and strong discontinuity concepts applied to the slip sy...
Critical state plasticity. Part VII: Triggering a shear band in variably saturated porous media
Bifurcation Critical state theory Heterogeneity Mixed formulation Shear band Unsaturated porous media
2015/7/1
In a previous paper (Part VI), the impact of spatially varying density on the localization of deformation of granular materials has been quantified using mesoscopic representations of stresses and def...
Micropolar hypoplasticity for persistent shear band in heterogeneous granular materials
Finite elements Heterogeneity Hypoplasticity Micropolar theory Persistent shear band
2015/7/1
Persistent shear bands in heterogeneous materials develop progressively, rather than instantaneously. For a meaningful capture of this deformation pattern, the band must develop naturally and freely u...
On the pore-scale mechanisms leading to brittle and ductile deformation behavior of crystalline rocks
crystal plasticity deformation mechanisms finite element heterogeneity microfracture
2015/7/1
Deformation mechanisms at the pore scale are responsible for producing large strains in porous rocks. They include cataclastic flow, dislocation creep, dynamic recrystallization, diffusive mass transf...
Finite deformation formulation for embedded frictional crack with the extended finite element method
finite deformation frictional crack embedded discontinuity extended finite element
2015/7/1
We reformulate an extended finite element (FE) framework for embedded frictional cracks in elastoplastic solids to accommodate finite deformation, including finite stretching and rotation. For the FE ...
Stabilized low-order finite elements for frictional contact with the extended finite element method
Extended finite element Frictional contact Lagrange multipliers Penalty method Stabilized methods
2015/7/1
Contact problem suffers from a numerical instability similar to that encountered in incompressible elasticity, in which the normal contact pressure exhibits spurious oscillation. This oscillation does...
DEM simulation of impact force exerted by granular flow on rigid structures
Avalanche DEM Granular flow Impact force
2015/7/1
The paper presents a DEM model for simulating dry granular avalanche down an incline. Flow pattern and impact forces on rigid obstacles are considered. Results of the simulations are compared with exp...