1990 Vol. 7 No. 2
1990, 7(2): 1-13.
Abstract：
This paper presents a discrete process for boundary integral equation using the semi-analytical finite element. The three-Dimensional elastodyanmic problems have been simolified into one-dimensional numerical calculations by semi-analytical process twice of fun lamental solutions and trial functions. The moving boundary element method is used to describe the wave propagation in half-space. Some exam es such as wave propagation and wave diffraction were studied to show the higher accuracy, less computation work and great benifit of the numerical soultion.
This paper presents a discrete process for boundary integral equation using the semi-analytical finite element. The three-Dimensional elastodyanmic problems have been simolified into one-dimensional numerical calculations by semi-analytical process twice of fun lamental solutions and trial functions. The moving boundary element method is used to describe the wave propagation in half-space. Some exam es such as wave propagation and wave diffraction were studied to show the higher accuracy, less computation work and great benifit of the numerical soultion.
Abstract：
In this paper, based on Ref [1],[2], presented is a unified solution of complex variable function applied to the problem of hole for the square, rectangle, triangle and trapezoid. The solution is characterized by the wide and universal scope of application.
In this paper, based on Ref [1],[2], presented is a unified solution of complex variable function applied to the problem of hole for the square, rectangle, triangle and trapezoid. The solution is characterized by the wide and universal scope of application.
1990, 7(2): 25-34.
Abstract：
This paper Presents a generalized multiple principle, so the well-known multiple principle becomes a special case of it. With the aid of it, more and more multispan and multistory frames may be simplified a series of one-span and multistory frames in calculating them.
This paper Presents a generalized multiple principle, so the well-known multiple principle becomes a special case of it. With the aid of it, more and more multispan and multistory frames may be simplified a series of one-span and multistory frames in calculating them.
1990, 7(2): 35-43.
Abstract：
This paper derives the accurate solutions of cylinderical shell due to line load or line moment by constructing Green's function. The results are for any edge conditions. It is not necessary for this paper to find the particular solution, and the whole solutions are obtained by using the homogeneous reowlts. Therefore, it is iseful in both theory and praitice.
This paper derives the accurate solutions of cylinderical shell due to line load or line moment by constructing Green's function. The results are for any edge conditions. It is not necessary for this paper to find the particular solution, and the whole solutions are obtained by using the homogeneous reowlts. Therefore, it is iseful in both theory and praitice.
1990, 7(2): 44-48.
Abstract：
The tangential stress at the boundary can not been gained directly in the application of BEM to analysing elastic stress. In this paper, difference method is used for solving tangential stress at the boundary on the basis of BEM. The difference equations for the boundary tangential stress are derived in the case of constant boundary element. The calculation show that the method in this article is feasible, and simple and practical. The method and equations developed also can been used to calculate the boundary tangential stress in the case of higher boundary element.
The tangential stress at the boundary can not been gained directly in the application of BEM to analysing elastic stress. In this paper, difference method is used for solving tangential stress at the boundary on the basis of BEM. The difference equations for the boundary tangential stress are derived in the case of constant boundary element. The calculation show that the method in this article is feasible, and simple and practical. The method and equations developed also can been used to calculate the boundary tangential stress in the case of higher boundary element.
Abstract：
On the basia of the experimental results of 20 specimens with rectangular transverse reinforcement which are under monotonic and cyclic loadings, the effect of the axial load and hoop retios on the ductility of columns is studied. The full-range curve of reinforced concrete members with flexure and axial loads is obtained by finite element method. After the analysis for the experimental and calculated results, a formula for the detemination of quantity of rectangular hoops in the plastic hinge region is given in this paper.
On the basia of the experimental results of 20 specimens with rectangular transverse reinforcement which are under monotonic and cyclic loadings, the effect of the axial load and hoop retios on the ductility of columns is studied. The full-range curve of reinforced concrete members with flexure and axial loads is obtained by finite element method. After the analysis for the experimental and calculated results, a formula for the detemination of quantity of rectangular hoops in the plastic hinge region is given in this paper.
1990, 7(2): 57-61.
Abstract：
The Boundary Element Method with 8-nodes quatratic elements is used for the computation of stress intensity factors of surface crack problems. The 8-nodes singlar elements are used along the crack front. In order to transmit easily from densed network to sparse network the 4 to 8 nodes element are used on the other boundary. The integral method of equal precision and other numerical techniques used in the paper improve the effectiveness of the solution in some way. The comparsion with Newman's high degree finite element solution shows that a satisfactory result has been obtained by much less nodes.
The Boundary Element Method with 8-nodes quatratic elements is used for the computation of stress intensity factors of surface crack problems. The 8-nodes singlar elements are used along the crack front. In order to transmit easily from densed network to sparse network the 4 to 8 nodes element are used on the other boundary. The integral method of equal precision and other numerical techniques used in the paper improve the effectiveness of the solution in some way. The comparsion with Newman's high degree finite element solution shows that a satisfactory result has been obtained by much less nodes.
1990, 7(2): 62-70.
Abstract：
The nonlinear dynamic time history analysis of tall framed structures is presented in this paper. In order to reveal the nonlinear behavior of beams and columns of framed structures, a more exact nonlinear beam model based directly on moment-curvature hysteresis loops is proposed. The type of hysteresis loops can arbitrarily be chosen, and the corresponding element stiffness matrix can be built up in a simple way. An exact technique of substrutural nonlinear dynamic analysis is also presented. With the technique proposed, direct dynamic analysis of large tall building structures can be carried out in a micro-computer.
The nonlinear dynamic time history analysis of tall framed structures is presented in this paper. In order to reveal the nonlinear behavior of beams and columns of framed structures, a more exact nonlinear beam model based directly on moment-curvature hysteresis loops is proposed. The type of hysteresis loops can arbitrarily be chosen, and the corresponding element stiffness matrix can be built up in a simple way. An exact technique of substrutural nonlinear dynamic analysis is also presented. With the technique proposed, direct dynamic analysis of large tall building structures can be carried out in a micro-computer.
1990, 7(2): 71-82.
Abstract：
This paper for the first time put forward an analysis of curved plate arch bridges with curved thick shell elements. The performance of the curved thick shell elements has been compared favourably against the results obtained from the 3D-solid elements analysis and the experimental results. It shows that the curved thick shell element analysis of curved plate arch bridges is quite valid. The curved plate arch bridges may be analysed with the IBM personal computer.
This paper for the first time put forward an analysis of curved plate arch bridges with curved thick shell elements. The performance of the curved thick shell elements has been compared favourably against the results obtained from the 3D-solid elements analysis and the experimental results. It shows that the curved thick shell element analysis of curved plate arch bridges is quite valid. The curved plate arch bridges may be analysed with the IBM personal computer.
1990, 7(2): 83-92.
Abstract：
In this paper, a exact solution of bending problem for the thick circular plate under a ccntric concentrated load with free edges on homogeneous half-space elastic foundation is obtained. The numerical examples is given.
In this paper, a exact solution of bending problem for the thick circular plate under a ccntric concentrated load with free edges on homogeneous half-space elastic foundation is obtained. The numerical examples is given.
1990, 7(2): 93-102.
Abstract：
This paper calculates the elasto-plastic problem of elliptical tunnelwith perturbation methods. It is supposed that material is ideally elasto-plastic according with Coulomb yielding critcrion and an annular region around tunnel has entered plastic yield. This paper gives analytical expressions of the stress, and elasco-plastic interface when second step small amount is concerned. In last examples, mechanical characteristic of the plastic region form and tunnel form isdiscusscd ualitatively and quantitatively.
This paper calculates the elasto-plastic problem of elliptical tunnelwith perturbation methods. It is supposed that material is ideally elasto-plastic according with Coulomb yielding critcrion and an annular region around tunnel has entered plastic yield. This paper gives analytical expressions of the stress, and elasco-plastic interface when second step small amount is concerned. In last examples, mechanical characteristic of the plastic region form and tunnel form isdiscusscd ualitatively and quantitatively.
1990, 7(2): 103-113.
Abstract：
This paper describes a simple mechanical model to predict notch tip opening displacement of 2Cr13 Steel under three point bending load and presents a criteria for engineering crack initiation at the tip of notches under three point bending load with the help of local stress-strain calculation. The initiated crack length is also defined in the paper. All the values by theoretical calculation are in good agreement with experimental results.
This paper describes a simple mechanical model to predict notch tip opening displacement of 2Cr13 Steel under three point bending load and presents a criteria for engineering crack initiation at the tip of notches under three point bending load with the help of local stress-strain calculation. The initiated crack length is also defined in the paper. All the values by theoretical calculation are in good agreement with experimental results.
1990, 7(2): 114-119.
Abstract：
In this paper, the shape of an elastic body suffered plane stress is optimized by Boundary Element Method and Sequential Uneostrained Minimization Technique. In process of optimization, the multiple objective problem is treated by fictitious objective method. To aviod teaious sensitivity analysis, the "New Simplex Method" is used and the satisfactory result of the example is obtained.
In this paper, the shape of an elastic body suffered plane stress is optimized by Boundary Element Method and Sequential Uneostrained Minimization Technique. In process of optimization, the multiple objective problem is treated by fictitious objective method. To aviod teaious sensitivity analysis, the "New Simplex Method" is used and the satisfactory result of the example is obtained.
1990, 7(2): 120-127.
Abstract：
On the basis of the force method in structural mechanics. Using the theory of linear space and the principle of mininum strain energy, the further research of the force method is done in this paper. The concept of solution space in statically indeterminate structure have been developed and the generalized equations of force method have derived. In computing the flexibility coefficient δij and free term △ip, as the different basic statically determinate structures can be established, it is obvious that forming the linear equations will be simplified to a certain extent. Also, this paper further perfacts the theory of force method, and it will be some help to us for recognizing the nature of solution in statically indeterminate structure.
On the basis of the force method in structural mechanics. Using the theory of linear space and the principle of mininum strain energy, the further research of the force method is done in this paper. The concept of solution space in statically indeterminate structure have been developed and the generalized equations of force method have derived. In computing the flexibility coefficient δij and free term △ip, as the different basic statically determinate structures can be established, it is obvious that forming the linear equations will be simplified to a certain extent. Also, this paper further perfacts the theory of force method, and it will be some help to us for recognizing the nature of solution in statically indeterminate structure.
Abstract：
This paper gives the application of formulae τ=Qrm2/Icosθ and τ= 2Q/A when μ=0～0.5 the first formulais used for t/D≤1/20.95～1/15.02,other t/D≤1/19.95～1/13.95.
This paper gives the application of formulae τ=Qrm2/Icosθ and τ= 2Q/A when μ=0～0.5 the first formulais used for t/D≤1/20.95～1/15.02,other t/D≤1/19.95～1/13.95.
1990, 7(2): 132-135.
Abstract：
This paper recombined slope and displacement of joints in indeterminate structure, the new system of displacement moment is developed, the canonical equations of displacement method is simplified. This problem is of a certain practical meaning.
This paper recombined slope and displacement of joints in indeterminate structure, the new system of displacement moment is developed, the canonical equations of displacement method is simplified. This problem is of a certain practical meaning.
1990, 7(2): 136-139.
Abstract：
In this paper, it is pescntcd the latest developments for the Theory of Beltrami-Haigh's Maximum Strain energy per unit volume and its application of engineering.
In this paper, it is pescntcd the latest developments for the Theory of Beltrami-Haigh's Maximum Strain energy per unit volume and its application of engineering.
1990, 7(2): 140-144.
Abstract：
It is difficult to analysis concentrated force by common BEM. In this paper, A new method is berived to solve the problem concerned concentrated force. The examples show that. the method is efficient. With high accuracy and less elements, the special BEM can reflect the results of concentrated loads efficiently.
It is difficult to analysis concentrated force by common BEM. In this paper, A new method is berived to solve the problem concerned concentrated force. The examples show that. the method is efficient. With high accuracy and less elements, the special BEM can reflect the results of concentrated loads efficiently.
