ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1993.tb00210.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Abstract:A knowledge‐based system, FREEMESH, for free mesh generation of quadrilateral elements in general two‐dimensional structures, is introduced in this paper. Based on the recursive logic, a plane domain is firstly represented with boundary features, corresponding to which a group of heuristic rules is built up to generate quadrilaterals recursively. The niles include the initial design rules and the redesign rules. To facilitate the rule‐based inference, the geometric reasoning is turned to acquire domain boundary features. Examples show that this strategy is effe

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1993.tb00211.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Abstract:Knowledge representation approaches and knowledge base management strategies in the concrete building structural detail design system KJICAD are described. A load combination algebra system is developed for environmental loads formalization and a code‐based problem‐solving control structure is established to describe design knowledge sources and their relations. By using compiler techniques, the physical knowledge base is made uniform and simplified for quick access. Finally, a practical design example is included to illustrate the effectiveness of KJI

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1993.tb00212.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Abstract:A powerful new method for dealing with stationary random seismic response is described in detail. It is an extension of the early‐stage method. The emphasis is focused on multi‐support excitation problems. The main features of this method are:1The computational efficiency is much higher than for the conventional method, e.g. approximately 10,100, or even more times faster.2All cross‐correlation items, whether between the support excitations or between the participant modes, are involved naturally. Practically, it is impossible for this method to neglect these items3The principles and algorithm are simple and easy for engineering application. Complex 3D FEM models with dozens of ground excitations can be easily analysed on microcomputers as small as IBM‐pc/ AT.4The non‐proportional damping matrix can be dealt with easily and accurately and only real eigenmodes are used for degree

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1993.tb00213.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Abstract:For dynamic analysis of interaction between structure and soil foundation, the elimination of wave reflecting on the artificial finite element boundary of semi‐infinite body is an essential problem. In this paper, a non‐reflecting boundary method with constant acceleration and constant force applied at the boundary is presented. A Corresponding explicit‐implicit algorithm for dynamic analysis of the semi‐infinite body is given. A good agreement of solutions is obtained as compared with the generalized Smith non‐reflecting boundary method with constant velocity and constant boundary force conditions. But it is much easier to implement, arid the computational effort and the storage required are considerabl

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1993.tb00214.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Abstract:The contact element formulation presented considers microscopically mechanisms of force transmission and heat exchange together with coupling between thermal and mechanical fields. Experimentally and theoretically well founded micro‐mechanical and micro‐thermal laws are adapted to FEM consistent linearization necessities. Based on these laws the nonlinear macroscopic related stiffness is calculated as a function of changes in significant parameters.Examples related to industrial applications are sh

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1993.tb00215.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Abstract:Based on the analogy between computational structural mechanics and optimal control, the multilevel substructural analysis method in structural mechanics is used for the solution of a nonlinear optimal control problem. The nonlinear control system is linearized first and the mixed energy of time‐interval is introduced, then the condensation equations of the time‐interval mixed energy are established according to the variational principle as in the theory of structural mechanics. The problem of the optimal solution for nonlinear control system is conside

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1993.tb00216.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Abstract:In this work, a simple C° isoparametric higher‐order plate element is developed to study the free vibration analysis of bimodulus laminated plates. The eqriations of motion for the higher‐order plate theory are also derived variationally. The warping of cross section and transverse shear deformation are both considered. The natural frequencies and neutral surface locations are determined for benchmark problems. Compared with available analytical solutions, fast convergence and excellent agreement are observed for the present finite element formula

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1993.tb00217.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY