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A general methodology for deriving thin plate bending elements with a single degree of freedom per node is presented. The formulation is based on the combination of a standard C0 finite element interpolation for the deflection field with an independent approximation of the curvatures which are expressed in terms of the deflection gradient along the sides using a finite volume‐like approach. The formulation is particularized for the simplest element of the family, i.e. the three node triangle with three degrees of freedom. The potential of the new element is shown through different examples of application.

This investigation assesses the bending performance of triangular plate elements with only three translational degrees of freedom per node in which the out‐of‐plane degree of freedom is the only displacement considered. A review is presented of three element formulations followed by the results of a series of case studies which illustrate the element behaviour. Results obtained from elastic theory and finite element analysis using more complex element formulations are given for comparative purposes.

The paper describes the application of the simple rotation‐free basic shell triangle (BST) to the non‐linear analysis of shell structures using an explicit dynamic formulation. The derivation of the BST element involving translational degrees of freedom only using a combined finite element–finite volume formulation is briefly presented. Details of the treatment of geometrical and material non linearities for the dynamic solution using an updated Lagrangian description and an hypoelastic constitutive law are given. The efficiency of the BST element for the non linear transient analysis of shells using an explicit dynamic integration scheme is shown in a number of examples of application including problems with frictional contact situations.

This article deals with improvement of eigenvalues obtained by finite element analysis of C¹ eigenproblems. The proposed method employs high order gradient smoothing at nodal points to derive improved high order interpolation functions for the single element of each mode. Two different schemes were developed for 1–D C¹ eigenproblems (free vibration of beams) and for 2–D quasi C¹ eigenproblems (transverse vibrations of thin plates). High order Hermitian polynomials are used for the beam problem together with some boundary node corrections, while a combination of high‐order and low‐order approximations are used for the modified formulation of the plate problem. Several smoothing options are proposed for both schemes. Numerical results for both schemes are used as examples to demonstrate the accuracy of the present approach.

A tailored graphical user interface (GUI) for finite element analysis, fully integrated into Microsoft Windows 3.1, has been developed. The current application is the simulation of flat sheet extrusion of thermoplastics, but many of the features would be common to a wide range of finite element analyses. Microsoft’s C/C++ Professional Development System 7.0, including the Software Development Kit 3.1 (SDK), has been used as the programming tool for the GUI. The interface is based on the Common User Access Advanced Interface Design Guide, which is part of the IBM Systems Application Architecture Library, and The Windows Interface: An Application Design Guide, which is part of the SDK. A memory handling technique is proposed to break the imposed 64 KB data segmentation. Connected finite element calculation routines are written in Fortran and compiled by the Salford FTN77/x86 32‐bit compiler. The protected mode interface of the Fortran compiler allows direct access by the GUI, and allows the computation to run as a 32‐bit background application, without memory limitations, in the multitasking environment. Finite element routines are supported by pre‐ and post‐processors comprising mesh generation, post‐processing for derived results, and graphical displays. A convenient contouring algorithm is proposed to generate contoured plots of nodal quantities in the form of iso‐lines or iso‐fields.

This paper aims to propose an efficient method to conduct the preliminary analyses of medium or high-rise wall-frame structural systems with vertically varying properties. To this end, a finite element is formulated to take the shear deformation of the shear wall and the constrained moment of the link beam.

The differential equation of the structure is derived from the total potential energy. Its homogenous solutions are functions of initial parameters (deflections and inner forces). To solve the structure with vertically non-uniform properties, the authors first use the classical Timoshenko beam element and then heuristically propose a finite element that uses the initial parameter solutions as shape functions and is easier to implement. A post-processing method to compute the shear force in the frame and shear wall is developed. Modal analysis using the consistent mass matrix is also incorporated. Numerical examples demonstrate the accuracy and mesh independency of the proposed element.

The shear deformation of the shear wall and the constrained moment of the link beam significantly influence the static response of the structure. Taking into account the shear deformation can eliminate the misleading result of zero-base shear force of the frame and give much better predictions of the system natural frequencies.

The proposed method achieves higher accuracy than the classical approach most often used. The finite element formulation derived from transformations of the initial parameter solutions is simple and has superior numerical performance. The post-processing method allows for a fast determination of the shear force distributions in the shear wall and frame.

A boundary element method for solving problems dealing with the dynamic analysis of thin elastoplastic flexural plates of arbitrary geometry and conditions inside the domain is proposed here. All possible edge boundary conditions, with any interior support conditions, such as isolated points (columns), lines (walls) or regions (patches) can be treated. The formulation by using the static fundamental solution of the problem leads to a system of boundary integral equations involving values of the layers along the edge. The solution of the problem with interior support conditions is achieved by an elimination of the unknown boundary layers. Subsequently, a descritization leads to a system of simultaneous algebraic equations which is solved numerically. A step‐by‐step time integration algorithm is employed to evaluate the dynamic inelastic response of the plate. Several examples are presented to illustrate the efficiency of the method.

The mixed finite element formulation using the Galerkin method is developed for the small deflection of a plate. This equation requires only linear shape functions to give compatibility. Furthermore only two degrees of freedom per node are needed. Hence, the formulated equation has several advantages compared with other methods.

The purpose of this paper is to develop an effective numerical approach to assess the nonlinear dynamic responses of a near‐bed submarine pipeline.

A coupled numerical approach is proposed in this paper to assess the nonlinear dynamic responses of this pipeline. The boundary‐element method is first used to get the nonlinear dynamic fluid loading induced by the asymmetric flow. The meshless technique is used to discretize the structure of the pipeline. A numerical example is first presented to verify the effectivity of the present method. Then, the coupled technique is used to simulate the nonlinear dynamic fluid‐structure interaction problem of a near‐bed pipeline. A Newton‐Raphson iteration procedure is used herein to solve the nonlinear system of equations, and the Newmark method is adopted for the time integration.

The presence of seabed results in a large negative lift on a pipeline in a horizontal current. Studies reveal that there exists a critical current velocity, above which the pipeline will become instable, and the critical velocity is significantly affected by the initial gap from the pipeline to the seabed.

The near‐bed submarine pipeline is a widely used structure in marine engineering. This paper originally develops a numerical approach to model this special fluid‐structure interaction problem. It has demonstrated by the examples that the present approach is very effective and has good potential in the practical applications.

This paper aims to present nonlinear numerical simulations using the versatile finite element (FE) analysis tool ANSYS and theoretical analysis based on code provisions to assess the load-carrying capacity of reinforced concrete (RC) beams under two-point monotonic static loadings.

Four quarter-size FE models with load and geometry symmetry conditions were constructed, the load-bearing capacity and associated mid-span deflections at critical points are verified against the full-scale experimental RC beams available in the literature. These developed FE models incorporated the tension stiffening effects and bond–slip behaviour. Theoretical analyses based on Indian standard code IS: 456–2000 and ACI 318–19 were also carried to verify the experimental and numerical predicted moments at critical loading points.

The load-deflection curves predicted through FE models exhibit closer corroboration with the experimental curves throughout the loading history. The contour plots for deflections, concrete principal stresses, reinforcement yield stresses are satisfactorily predicted by the FE models, which reveal the complete information of nonlinear behaviour of RC beams. The developed model well captured the initial and progressive crack patterns at each load increments.

The FE modelling is an efficient, valid and economical tool that is an alternative to the expensive experimental program and can be used to explore, analyse and fully understand the nonlinear response of RC beams under static loadings.

The ultimate moment capacity evaluated based on ACI 318–19 code provision show a better correlation with the experimental data as compared to the IS: 456–2000 code provision. The ultimate loads and associated centre-span deflections predicted by RN-2, RN-3, RB-12 and RB-16 FE model show a discrepancy of 1.66 and –0.49%, –4.68 and –0.60%, –9.38 and –14.53% and –4.37 and 4.21%, respectively, against the experimental results, which reveals that the developed ANSYS FE models predict consistent results and achieved a reasonable agreement with the experimental data.