结构动力反应分析的三阶显式方法   总被引：14，自引：6，他引：14  

张晓志  程岩  谢礼立 《地震工程与工程振动》2002,22(3):1-8

本通过对传统动力反应分析方法的总结，阐明了建立隐式和显式方法的一般思路及数学本质，提出了使用系统位移反向向量三阶导数的隐工和实用显式积分方法－3阶显式方法，分析了该显式方法的精度和稳定性，并对建立更高阶隐式和显式方法以及方法的精度和稳定性作了初步讨论。最后，通过算例对本方法、献[1]方法和经典的常平均加速度法（隐式方法、视为精确解）的精度和稳定性进行了比较分析。结果表明，本方法具有明显的优点。  相似文献   

地图数学定义的研究     

钟业勋  李占元 《武汉大学学报(信息科学版)》1997,(2)

在地图内容和形式数学表示的基础上研究了地图的数学定义。由于引入隐式地图和变换条件，故所有储存地图信息的载体均可属于地图的范围，从而使地图定义获得了广义的解释和精确的表达  相似文献   

非静力中尺度模式的现状及发展趋势   总被引：1，自引：0，他引：1       下载免费PDF全文

杨学胜  陈德辉  张红亮  胡江林 《气象》2004,30(1):3-7

随着高性能计算机与大气探测技术的发展 ,使得非静力中尺度数值预报模式的业务化成为可能 ,世界上主要的气象中心最近几年纷纷发展非静力中尺度模式 ,并取得了重要进展 ,这其中尤以英国气象局新发展的非静力通用模式最为突出。基于此 ,介绍了近年来国际上发达国家的非静力中尺度预报模式的现状及发展方向 ,并对该类模式设计中应注意的一些问题进行了阐述  相似文献   

Anisotropic damage of rock joints during cyclic loading: constitutive framework and numerical integration     

Joshua A. White 《国际地质力学数值与分析法杂志》2014,38(10):1036-1057

This work describes a constitutive framework for modeling the behavior of rough joints under cyclic loading. Particular attention is paid to the intrinsic links between dilatancy, surface degradation, and mobilized shear strength. The framework also accounts for the important effect of shear‐induced anisotropy. The resulting approach is fully three‐dimensional and is not restricted to plane‐displacement kinematics. Both the governing formulation and an algorithm for implicit numerical integration are presented. While the proposed methods are general, we also postulate a specific model that is compared with experimental data. It employs relatively few free parameters but shows good agreement with laboratory tests. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

Computation of wind-wave spectra in coastal waters with SWAN on unstructured grids     

M. Zijlema 《Coastal Engineering》2010

An unstructured-grid procedure for SWAN is presented. It is a vertex-based, fully implicit, finite difference method which can accommodate unstructured meshes with a high variability in geographic resolution suitable for representing complicated bottom topography in shallow areas and irregular shoreline. The numerical solution is found by means of a point-to-point multi-directional Gauss–Seidel iteration method requiring a number of sweeps through the grid. The approach is stable for any time step while permitting local mesh refinements in areas of interest. A number of applications are shown to verify the correctness and numerical accuracy of the unstructured version of SWAN.  相似文献   

IMPLICIT NONLINEAR NORMAL MODE INITIALIZATION:A MULTIGRID APPROACH          下载免费PDF全文

D.R.C.Nair  B.Chakravarty  P.Niyogi 《Acta Meteorologica Sinica》1993,(1)

The implicit nonlinear normal mode initialization (INMI) is applied to a tropical limited area shallow water modelin spherical coordinates.The boundary condition for the INMI scheme is based on the boundary formulation of themodel.The INMI scheme is found to be very efficient in suppressing spurious gravity wave oscillation and providing awell balanced initial data set for the model.The INMI scheme involves solving a number of elliptic type equations withvarying complexity.and hence an efficient numerical technique is required for solving such equations.In order to makeINMI computationally more attractive,we are employing the multigrid method for solving all the elliptic type equationsin the INMI scheme.The numerical procedures for the development of such multigrid solvers are briefly described.  相似文献   

磁层亚暴扩展相的数值模拟          下载免费PDF全文

金曙平 《地球物理学报》1990,33(6):629-638

本文用多步隐格式方法,求解包含电阻的磁流体力学方程组,对磁层亚暴扩展相作数值模拟.计算结果展现了亚暴扩展相期间磁尾变化的主要特征.它表明,球向和尾向等离子体流与准稳态重联有关.等离子体团的尾向喷发,致使中性线尾侧电流片内的密度降低,等离子体片变薄.中性线近地侧的等离子体团朝着地球运动,并合并于地球附近的重联区内.  相似文献   

Equivalent force control method for generalized real‐time substructure testing with implicit integration     

Bin Wu  Qianying Wang  P. Benson Shing  Jinping Ou 《地震工程与结构动力学》2007,36(9):1127-1149

This paper presents a new method, called the equivalent force control method, for solving the nonlinear equations of motion in a real‐time substructure test using an implicit time integration algorithm. The method replaces the numerical iteration in implicit integration with a force‐feedback control loop, while displacement control is retained to control the motion of an actuator. The method is formulated in such a way that it represents a unified approach that also encompasses the effective force test method. The accuracy and effectiveness of the method have been demonstrated with numerical simulations of real‐time substructure tests with physical substructures represented by spring and damper elements, respectively. The method has also been validated with actual tests in which a Magnetorheological damper was used as the physical substructure. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

摩擦与粘性流体耗能器串联体系动力分析     

吕西林  周强 《地震工程与工程振动》2001,21(1):123-130

采用粘性屈服模型来模拟摩擦耗能器的力－速度关系，建立了摩擦与粘性流体耗能器串联耗能体系的动力分析方法．为考虑框架杆件和支撑材料的几何非线性，采用增量型Ｒｏｓｅｎｂｒｏｃｋ二级三阶半隐式Ｒｕｎｇｅ－Ｋｕｔｔａ法求解动力方程．比较了仅有摩擦耗能器体系与串联组合耗能体系的减振效果，分析了粘性流体耗能器参数对组合耗能体系减振效果的影响。  相似文献   

摩擦耗能框架体系动力分析   总被引：4，自引：0，他引：4  

周强  吕西林 《地震工程与工程振动》2001,21(2):136-144

采用粘性屈服模型来模拟摩擦耗能器的力－速度关系。建立了带有摩擦耗能器体系的动力分析8方法，采用增量型Rosenbrock二阶三阶半隐式Runge-Kutta法求解动力方程，得到了带有摩擦耗能器单层框架在正弦波激励下反应的解析解，并据此验证粘性屈服模型及求解动力方程算法的正确性，分析了摩擦耗能器的起滑力和支撑刚度对耗能减振效果的影响。  相似文献