Loubignac' s iterative method provides both displacement and stress continuous fields,and computed results are more accurate than those provided by classical displacement finite element method.

The paper analyzes and discusses the law that the result precision of thermal stress is affected by the proportionments of element border length, border condition, form function and so on, and compares the method with displacement finite element method being used.

In the case of thermal stress analysis of steam turbine rotors based on the finite element methods, the precision in thermal stress calculation by displacement finite element in common use is analyzed. The advantage and disadvantage of the multi-variable hybrid finite elements, the stress hybrid element, the hybrid element etc, are briefly stated.

By using displacement finite element based on the global-local displacement hypothesis1,2-3 higher-order theory,we calculate the displacement and interlayer stress of random angle laid laminated composites. The results of numerical calculation show that displacement finite element based on higher-order theory can calculate accurately not only the displacement of the laminated composites but also transverse shear stresses.

By using the methods of response displacement, finite element response displacement and finite element dynamic analysis, the Port-Island wave of Hyoko Ken Nanbu (Kobe) earthquake was input to analyze the shallowly buried trunk subway structure with the considerations of slippage and coming away between the structure and soil under certain geological condition.

Based on interval analysis and displacement finite element method, the static displacement response analysis of structure comes down to solve the interval finite element control equation.

In the present paper, boundary condition problems in the Rayleigh-Ritz and displacement finite element methods are discussed in viewpoint of teaching method, and several illustrative examples are Ikied to demonstrate the effects of the imposition of mechanical boundary conditions which is theoretically unnecessary in the displacement method.

The numerical results show that thestress-intensity factors given by this method are in good agreement with those by 3-D finite element method, more accurate than those by the method based on displacement finite element combined with line-spring model.

Comparison of the present solution with an assumed displacement finite element solution is made to demonstrate the accuracy and efficiency of the present approach.

In this method, a complex variable formulation in conjunction with a hybrid displacement finite element scheme is used to carry out the stiffness and stress calculations of finite cracked plates subjected to general boundary and loading conditions.

A hybrid-displacement finite element model for the bending analysis of thin cracked plates

This follows from the projection theorem describing finite element analysis which shows that the stresses computed by the displacement finite element procedure are abest approximation of the true stresses at an element as well as global level.

A good agreement of the results with theoretical solutions, and better performance compared with displacement finite element method, are observed.

In the present paper, boundary condition problems in the Rayleigh-Ritz and displacement finite element methods are discussed in viewpoint of teaching method, and several illustrative examples are Ikied to demonstrate the effects of the imposition of mechanical boundary conditions which is theoretically unnecessary in the displacement method.

Based on the potential energy action functional (1) for dynamic analysis of fluid-solid interaction problems, where some rotations in a com-pressible-inviscid fluid have been constrained by means of a penalty coefficient B, formulas (16), (19), (20) and (22) of a compatible finite element and the corresponding substructure-subdomain model are derived. A computer program - FSIAP has been developed. Some examples concerning earthquake response of a Dam-water system are calculated. The results drawn in Fig. 2-Fig....

Based on the potential energy action functional (1) for dynamic analysis of fluid-solid interaction problems, where some rotations in a com-pressible-inviscid fluid have been constrained by means of a penalty coefficient B, formulas (16), (19), (20) and (22) of a compatible finite element and the corresponding substructure-subdomain model are derived. A computer program - FSIAP has been developed. Some examples concerning earthquake response of a Dam-water system are calculated. The results drawn in Fig. 2-Fig. 7 and listed in Table 1 show that the displacement finite element method with the frequency shift technique and the substructure-subdomain technique described in the paper is appealing. for computing dynamic response of fluid-solid interaction systems and that with the same accuracy the mode synthesis method is much more economical than general finite element methods.

In the last ten years or so, many investigators have devoted themselves to the study of the opening/closuring of a stationary and propagating crack. Newman [1] was the first one to perform the fatigue crack closure by using Elastic-Plastic Finite Element Method (EPFEM) with corrective iterations. Ref. [21 discussed further a material with crack by employing FEM nonlinear analysis. Nakagaki and Atluri [3] used a hybrid-displacement finite element to treat the stress and strain singularities near the crack...

In the last ten years or so, many investigators have devoted themselves to the study of the opening/closuring of a stationary and propagating crack. Newman [1] was the first one to perform the fatigue crack closure by using Elastic-Plastic Finite Element Method (EPFEM) with corrective iterations. Ref. [21 discussed further a material with crack by employing FEM nonlinear analysis. Nakagaki and Atluri [3] used a hybrid-displacement finite element to treat the stress and strain singularities near the crack tip, and analyzed the crack closure under four types of pulse cyclic loading. Miyamoto [4] researched into the elastic plastic response of the crack tip and the opening/closuring phenomenon with constant-strain finite element. However, the methods of analysis in References [3] and [4] are both rather time-consuming. The present paper is limited to analysing the opening/closuring phenomenon of a stationary crack with the First Order Selfcorrection method, utilizing the Elastic-Plastic FEM. It allows step-by-step calculation without iteration. Furthermore, the effect of the peak overload of cyclic loading on opening/closuring behavior of the crack is discussed. It was shown in Ref. [5] that the method provides enough accuracy and reduces the computational time. Of course, the present paper deals with a problem more complicated than that in Ref. [5]. Just as expected, the method still provides enough accuracy and reduces computational time. In the paper, stress distribution, strain distribution and plastic zone size are calculated. The behavior of crack opening/closuring under alternating load with different ratios of overload is given. The major findings are as follows: (1) the damage level due to retardation effects decreases with the value of the peak overload; (2) the damage due to a plus load and a subsequent minus compressive overload is severe.