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Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the theoretical as well as practical points of view. The range of applications of FEMs in this area is wide and cannot be presented in a single paper; therefore aims to give the reader an encyclopaedic view on the subject. The bibliography at the end of the paper contains 2,025 references to papers, conference proceedings and theses/dissertations dealing with the analysis of beams, columns, rods, bars, cables, discs, blades, shafts, membranes, plates and shells that were published in 1992‐1995.

Stab-resistant body armor (SRBA) is used to protect the body from sharp knives. However, most SRBA materials currently have the disadvantages of large weight and thickness. This paper aims to prepare lightweight and high-performance SRBA by 3D printing truss structure and resin-filling method.

The stab resistance truss structure was prepared by the fused deposition modeling method, and the composite structure was formed after filling with resin for dynamic and quasi-static stab tests. The optimized structural plate can meet the standard GA68-2019. Digital image correlation technology was used to analyze the local strain changes during puncture. The puncture failure mode was summarized by the final failure morphologies. The explicit dynamics module in ANSYS Workbench was used to analyze the design of the overlapped structure stab resistance process in this paper.

The stab resistance performance of the 3D-printed structural plate is affected by the internal filling pattern. The stab resistance performance of 3D-printed structural parts was significantly improved after resin filling. The 50%-diamond-PLA-epoxy, with a thickness of only 5 mm was able to meet the stab resistance standard. Resins are used to increase the strength and hardness of the material but also to increase crack propagation and reduce the toughness of the material. The overlapping semicircular structure was inspired by the exoskeleton structure of the demon iron beetle, which improved the stab resistance between gaps. The truss structure can effectively disperse stress for toughening. The filled resin was reinforced by absorbing impact energy.

The 3D-printed resin-filled truss structure can be used to prepare high-performance stab resistance structural plates, which balance the toughness and strength of the overall structure and ultimately reduce the thickness and weight of the SRBA.

Although the actual residual stress distribution in any structural steel member can be only obtained by experimental measurements, it is known to be a difficult, tedious and inefficient piece of work with limited accuracy. Thus, besides aiming at clarifying structural designers and researchers about the possible ways of modelling residual stresses when performing finite element analysis (FEA), the purpose of this paper is to provide an effective literature review of the longitudinal membrane residual stress analytical expressions for carbon steel non-heavy sections, covering a vast range of structural shapes (plates, I, H, L, T, cruciform, SHS, RHS and LSB) and fabrication processes (hot-rolling, welding and cold-forming).

This is a literature review.

Those residual stresses are those often required as input of numerical analyses, since the other types are approximately accounted for through the s-e curves of coupons cut from member walls.

One of the most challenging aspects in FEA aimed to simulate the real behaviour of steel members, is the modelling of residual stresses.

Besides aiming at clarifying structural designers and researchers about the possible ways of modelling residual stresses when performing FEA, this paper also provides an effective literature review of the longitudinal membrane residual stress analytical expressions for carbon steel non-heavy sections, covering a vast range of structural shapes (plates, I, H, L, T, cruciform, SHS, RHS and LSB) and fabrication processes (hot-rolling, welding and cold-forming).

The purpose of this paper is to develop a structural vibration control system by using a state observer which estimates system states using displacements measured from sensors.

Friedlander's exponential decay function is used for expressing the blast load model. A semiloof shell element is developed in order to account for piezoelectric effects. The composite plate is discretized by using the semiloof shell elements, and stiffness and mass matrices of the plate are obtained from the finite element model. In order to reduce the degrees of freedom of the finite element model, mode summation method is used with weighted modal vector including initial dominant modes in the dynamic behavior.

The structural vibrations are suppressed successfully and in an optimal way by using a state observer control system which estimates system states using displacements measured from sensors.

This paper shows, for the first time, that vibrations of a cantilevered composite plate subjected to blast loading are suppressed by the use of piezoelectric actuators. The state observer and optimal linear quadratic regulator are both used at the same time to suppress the vibrations.

This paper deals with structural shape optimization of vibrating prismatic shells and folded plates. The finite strip method is used to determine the natural frequencies and modal shapes based on Mindlin‐Reissner shell theory which allows for transverse shear deformation and rotatory inertia effects. An automated optimization procedure is adopted which integrates finite strip analysis, parametric cubic spline geometry definition, automatic mesh generation, sensitivity analysis and mathematical programming methods. The objective is to maximize the fundamental frequency by changing thickness and shape design variables defining the cross‐section of the structure, with a constraint that the total volume of the structure remains constant. A series of examples is presented to highlight various features of the optimization procedure as well as the accuracy and efficiency of finite strip method.

The purpose of this paper is to compare between two methods of volume control in the context of topological derivative-based structural optimization of Kirchhoff plates.

The compliance topology optimization of Kirchhoff plates subjected to volume constraint is considered. In order to impose the volume constraint, two methods are presented. The first one is done by means of a linear penalization method. In this case, the penalty parameter is the coefficient of a linear term used to control the amount of material to be removed. The second approach is based on the Augmented Lagrangian method which has both, linear and quadratic terms. The coefficient of the quadratic part controls the Lagrange multiplier update of the linear part. The associated topological sensitivity is used to devise a structural design algorithm based on the topological derivative and a level-set domain representation method. Finally, some numerical experiments are presented allowing for a comparative analysis between the two methods of volume control from a qualitative point of view.

The linear penalization method does not provide direct control over the required volume fraction. In contrast, through the Augmented Lagrangian method it is possible to specify the final amount of material in the optimized structure.

A strictly simple topology design algorithm is devised and used in the context of compliance structural optimization of Kirchhoff plates under volume constraint. The proposed computational framework is quite general and can be applied in different engineering problems.

In the frame of the European RFCS TRAFIR project, three large compartment fire tests involving steel structure were conducted by Ulster University, aiming at understanding in which conditions a travelling fire develops, as well as how it behaves and impacts the surrounding structure.

During the experimental programme, the path and geometry of the travelling fire was studied and temperatures, heat fluxes and spread rates were measured. Influence of the travelling fire on the structural elements was also monitored during the travelling fire tests.

This paper provides details related to the influence of travelling fires on a central structural steel column.

The experimental data are presented in terms of the gas temperatures recorded in the test compartment near the column, as well as the temperatures recorded in the steel column at different levels. Because of the large data, only fire test one results are discussed in this paper.

The purpose of this study is to set up a dynamic model of material extrusion (ME) additive manufacturing plates for the prediction of their dynamic behavior (i.e. dynamic inherent characteristic, resonant response and damping) and also carry out its experimental validation and sensitivity analysis.

Based on the classical laminated plate theory, a dynamic model is established using the orthogonal polynomials method, taking into account the effect of lamination and orthogonal anisotropy. The dynamic inherent characteristics of the ME plate are worked out by Ritz method. The frequency-domain dynamic equations are then derived to solve the plates’ resonant responses, with which the damping ratio is figured out according to the half-power bandwidth method. Subsequently, a series of experimental tests are performed on the ME samples to obtain the measured data.

It is shown that the predictions and measurements in terms of dynamic behavior are in good agreement, validating the accuracy of the developed model. In addition, sensitivity analysis shows that increasing the elastic modulus or Poisson’s ratio will increase the corresponding natural frequency of the ME plate but decrease the resonant response. When the density is increased, both the natural frequency and resonant response will be decreased.

Future research can be focused on using the proposed model to investigate the effect of processing parameters on the ME parts’ dynamic behavior.

This study shows theoretical basis and technical insight into improving the forming quality and reliability of the ME parts.

A novel reliable dynamic model is set up to provide theoretical basis and principle to reveal the physical phenomena and mechanism of ME parts.

The purpose of this study is for a higer sustainability of the historic towns and centres. The task of the society is to minimize risk and guarantee maximun safety within the territory while safeguarding the natural as the built landscape. With these sometimes unfortunate outcomes in mind, the society continue to promote “informed planning” hoping to achieve ever grater sustainability and respect for the extant, but, in practice, what the society have done amounts to very little. Indeed, today’s historic city centrers remain neglected and are increasingly “unsafe”.

In the course, Italy introduced a set of regulations in an attempt to construct, transform, conserve and exploit the potential of historic cities. Unfortunately, the results were not outstanding and today we need to rethink their approach if we are to reverse the abandonment of historic centers and make those “safe” again. In an effort to understand if what was hitherto put in place is sufficient or if new strategies are called for, we have reviewed the technical measures issued. In a large number of cases, restoration only increased their fragility, whereas in many others, especially concerning small centers with traditional economies, no rehabilitation work was ever attempted, not even essential maintenance work, and thus their functional and physical obsolescence became manifest.

The variegated and complex fragility of such centers requires forms of planning that can take account of the environment, deploy city-planning measures and undertake structural and architectural adaptation. If regeneration is to lead to a “comprehensive and integrated vision” for solving urban problems, economic, physical and social improvement and appropriate environmental conditions for an area subject to transformation, it will require new national and local action policies able to guarantee physical safety, the conservation of cultural values and the social and economic regeneration of such centers within a framework of policies for equilibrated urban development.

The processes of repurposing/revamping and giving leverage to historic centers must make use of multidisciplinary approaches ranging from conservation needs to overall regeneration needs. Therefore, new formulas are needed to enable us to combine conservation based on protective constraints with formulas for rehabilitation, reuse and performance improvement that are couched less in terms of sustainability, and more in terms of profitability, according to the principle – repeatedly voiced in international forums – that assets are also economic resources. Therefore, it will be necessary to proceed carefully, by drawing up a program of territorial development strategies with due guarantees of feasibility and economic growth prospects.

An appropriate regulatory framework is certainly necessary for the regeneration of historic towns and centers but an even more important role should be played by projects that optimize the use of resources if we are to ensure that financing will be managed correctly and a connection will be created – given the discontinuity represented by new constructions – between what remains of extant historic and contemporary architecture and construction. In this context, contemporary architectural design and urban planning can help meet the continued requests for the refurbishment of consolidated cities and the reconstruction of earthquake-stricken towns.

Rehabilitating center is not a cultural luxury but a necessity that springs from the need to economize territorial and economic resources. Consequently, a methodology should be formulated to produce, in each specific case, a design jointly drawn up by town planners, architects, urban redevelopment experts, structural engineers and with the participation of many other specialist figures, such as economists, sociologists, geologists and engineering physicists.

This paper provides a multidisciplinary vision on regeneration.

The transverse shear deformation and rotary inertia effects need to be included for an accurate analysis in the response of the relatively thick plates. This paper seeks to use, one of the refined theories which takes into account those effects, The First Order Shear Deformation Theory, to obtain linear and non‐linear responses for anti‐symmetric angle‐ply composite plates under random excitation.

The random excitation is assumed to be stationary, ergodic and Gaussian with zero‐mean. A Monte Carlo Simulation of stationary random process is used. A multi‐mode Galerkin approach and numerical integration procedure are employed to find linear and non‐linear response solutions. Laminated composite plate is taken to be simply‐supported along four edges.

The vibration of composite plates at elevated temperatures is also investigated. The linear and non‐linear deflections root‐mean‐square (RMS) are obtained for various input levels, the different lamination angles and the number of layers.

Further, case studies might lead to a lighter design of thick panels used in high‐performance systems such as aerospace structures.

The paper provides information on the linear and more realistic non‐linear vibrations of thick composite plates in time domain so that it would be possible to obtain key statistical information directly from time‐response history.