Abstract:
In this paper, we employ the theory of matrices and continued fractions for the solution of the bending problem of continuous beams on elastic foundation with unyielding supports. End moments are obtained in explicit expressions. Accurate numerical results may be calculated from these expressions directly without salving simultaneous equations.

Abstract:
In this paper, some general variational principles in the theory of elasticity and the theory of plasticity are established. Consider an elastic body in equilibrium with small displacement. By regarding u, v, w, ex, ey, ez, yyz, yxz, yxy, σx,σy, σz,τyz,τxz,τxy as fifteen independent functions, and letting their variations be free from any restriction, we establish two variational principles, called the principle of generalized complementary energy and the principle of generalized potential energy. Each principle is equivalent to the four sets o?fundamental equations of the theory of elasticity, namely, the equations of equilibrium, the stress strain relations, the strain displacement relations and the appropriate boundary conditions. Special cases of these principles are examined. These principles are next expressed in other forms, where u, v, w, σx,σy, σz,τyz,τxz,τxy are regarded as nine independent functions with their variations free from any restrictions. Next we consider the bending of a thin elastic plate with supported edges under large deflection. By regarding Mx, My, Mxy, Nx, Ny, Nxy, u, v, w as nine independent functions with the restriction that w should vanish along the contour of the plate, we establish a variational principle, called the principle of generalized potential energy, which is equivalent to the three sets of fundamental equations in the theory of bending of thin plate, namely, the equations of equilibrium, the displacement stress relations (strain stress relations) and the appropriate boundary conditions. This principle is next expressed in another form which is more convenient for application. As an illustration, von Kármán's equations for the large deflection of thin plate are derived from this principle. In von Kármán's equations, one unknown is the deflection and the other unknown is the membrane stress function. Therefore it is impossible to derive von Karman's equations either from the principle of minimum potential energy or from the principle of complementary energy. Finally we consider the equilibrium of a plastic body with small displacement. In the case of the deformation type of stress strain relations, we establish two variational principles, each of which is equivalent to the equations of equilibrium, a certain type of stress strain relations and the appropriate boundary conditions. In these variational principles, u, v, w and their variations are free from any restriction, and σx,σy, σz,τyz,τxz,τxy and their variations satisfy a certain yield condition. In the case of the flow type of stress strain relations, we get two similar variational principles, in which u, v, w and their variations are free from any restriction, σx,σy, σz, τyz,τxz,τxy and their variations satisfy a certain yield condition and σx,σy, σz, τyz,τxz,τxy have no variations.

Abstract:
The problem of bending of orthotropic rectangular plates with clamped edges on elastic foundation may be reduced to the following differential equation and boundary conditions (?4w)/(?x4)+2λ(?4w)/(?x2?y2)+(?4w)/(?y4)+kw=q/D. w=0, (?w)/(?x)=0 at x=±a, w=0, (?w)/(?y)=0, at y=±b. In the case of isotropic plates, λ = 1. In this paper a perturbation method is proposed for the solution of this problem fay expanding w in power series of λ: w=w0+w1λ+w2λ2+……. It is proved that this series is convergent when -1 ≤λ≤1.

Abstract:
In a previous paper 1], we have obtained a general solution of three dimensional problem of the theory of elasticity for a transversely isotropic body. This general solution is applied in the present paper to the problem of equilibrium of a transversely isotropic half space. The following six problems are treated: 1) half space under given surface load, 2) half space under given surface displacement, 3) half space under given normal surface load and tangential surface displacement, 4) half space under given tangential surface load and normal surface displacement, 5) the contact problem of a rigid stamp upon a half space, 6) the problem of bending of thin plate resting upon a half space. It is found that, if, in problems 5) and 6), fricdonal force between stamp or plate and half space may be neglected, there exist simple relations between solutions for a transversely isotropic half space and corresponding solutions for an isotropic half space.

Abstract:
In this paper, the problem of torsion of prisms bounded by two intersecting circular cylinders is solved by means of Fourier's integrals. It is found that when the angle of intersection of these two circular cylinders is commensurable with π the stress function and the torsional rigidity of the prism can be expressed in closed form in terms of circular and hyperbolic sines and cosines.

Abstract:
In this paper, the snapping of a thin spherical cap under edge moment is considered. The snapping of the same cap under line load distributed along a circle as shown in Fig. 1 has been disscussed by Chien Wei-zang in two unpublished papers. His results are briefly summarized in this paper.

Abstract:
In this paper, we follow S. G. Lehnitzky in the study of the three-dimensional problems of a transversely isotropic body depending on three variables. We give up the restriction of S. G. Lehnitzky about deformation and reserve only the assumption about the elastic property of the body. The results of this paper give a wide possibility for the solution of special problems.