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81.
In this paper, the finite element method is used to analyze the behavior of the prestressed V-shape Slab Roof structure, especially the effect of temperature change on the stress of slab. The calculated results indicate that when the temperature changes, the tensile stress at the lower extreme fibers of the flange plate near rib exceeds the tensile strength of concrete subjected to the combined action of triaxial stresses and results in the longitudinal cracks of the flange plate. The deflection analysis is based on the mechanical model of the prestressed V shape slab with the longitudinal cracks. The calculated results are in general agreement with the field observations. 相似文献
82.
In contrast to the finite element method, another form of numerical method which is based on the using of rectangular math covers in manifold method is proposed. In this method, the element data is not a necessary in the input data files and it can be incorporated with the CAD technology conveniently. The theory and application of the method are discussed and the auto mesh algorithm of the cover system is also given in this paper. The numerical examples indicate that the method and the algorithm are accurate and effective. 相似文献
83.
Modeler and simulation modules in Ideas software are used to build the finite element models on involute gear and double involute gear with accurate tooth shape, and with the same design parameters and under the same loads, finite element contact analysis has been done. At last, the contact stress and bending stress on the two types gear transmission at the different meshing positions are solved out, and comparative analysis and study have been done. At the same time, that the ladder-shape tooth on the double involute gear how to influence contact stress and bending stress is emphatically analysed. All above offer the theoretical foundation that bring the double involute gear with ladder-shape tooth into the industry. 相似文献
84.
Bomsster is a key load-bearing part of railway lorry bogie.Because of its inherent defects casting-steel bomsster could not meet the demands of the heavy load,acceleration and security for lorry.So forging process is proposed to form it.The forming performance of forging-steel bomsster is analyzed.A forging technology is presented which realizes two forging-steel bomsster parts formed in one die.With the plastic forming simulation software DEFORM-3D,the simulation and optimization of the forming process of forging bomsster has been taken based on 3D rigid visco-plastic FEM theory.Optimized scheme has been used to direct the pilot product.The results of product's testing and application suggest that the new forging technology is feasible and the performance of the product is credibility and stabilization.The factory has realized large scale production of a series of forging-steel bomsster.Remarkable benefits of both economy and society have been achieved. 相似文献
85.
Yun Zhengqing Tan Bangding 《保鲜与加工》1993,(5):79-84
Based on [l].this paper presents a new spline-BEM for calculating 3-D electrostatic fields,in which bi-cubic B-splines are used as basis functions. The corner problem in BEM and the extreme conditions for splines are circumvented. The numerical results presented show that the global approximation .convergence and stability of the method are satisfactory. 相似文献
86.
Li Runfang Li Yusheng 《保鲜与加工》1993,(1):96-101
A new finite element method is presented in this paper to analyze the thermo-
elastic contact problem with heat input on meshing tooth faces. The computational model of meshing gear has been established and the frictional heat input on meshing tooth faces is estimated. In addition, 2-D finite element analysis program for this kind of problem is listed. The test and practical examples are given to show the validity and versatility of this method. 相似文献
87.
88.
Yang Changqi 《保鲜与加工》1995,(1):81-86
This paper presents the basic equations and algorithm of vehicle crashworthinessbriefly.Take a light-truck for example,some applied problems in ustng Engineering WorkStationto analysis truck crashworthiness are discussed.A installation method of contact surface is intro-duced,Finally,a nurnerical simulation result is presented. 相似文献
89.
Qing Jialong 《保鲜与加工》1994,(3):54-59
Analysis is given to the direction characteristic of stress gradient in crackstructure by using three-dimensional line-type element,The purpose is considerably to reduce theoperation of computation and improve the computation precision in finite element analysis. 相似文献
90.
In order to settle some problems involved in applying ANSYS into nonlinear Finite Element Analysis of RC structure,this paper discusses the nonlinear FEM method for staggered joint,incorporating its experimental result.The main solved problems are as follows:(1) The fundamental process of nonlinear FEM analysis;(2) How to model the behaviors of reinforcement and concrete respectively;(3) How to model the bond-slip relationship between reinforcement and concrete. 相似文献