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This paper aims to propose a generalized finite element technique that can accurately approximate the solution of the flexural-shear cantilever model of wall-frame structures proposed by Heidebrecht and Stafford Smith.

This approach adopts scaled monomials as enrichment functions, and they are highly effective in accurately capturing the solution of the problem, as it consists of smooth functions such as polynomials, hyperbolic and trigonometric functions. Several numerical experiments are performed on the static and modal analyses of the flexural-shear cantilever wall-frame structures using the proposed generalized finite element method (GFEM), and their accuracies are compared with those obtained using the standard finite element method.

The proposed GFEM is able to achieve theoretical convergence rates of the static and modal analyses, which are, in principle, identical to those of the standard FEM, for various polynomial orders of its shape functions such as quadratic, cubic and quartic orders. The proposed GFEM with quartic enrichment functions can provide more accurate solutions than the standard FEM, and thus can be effectively used at the initial design stage of high-rise wall-frame structures.

This work is the first paper where the GFEM is applied to the analysis of high-rise wall-frame structures, and the developed technique can be used as a good analysis tool at the initial design stage.

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.

This bibliography contains references to papers, conference proceedings, theses and books dealing with finite strip, finite prism and finite layer analysis of structures, materially and/or geometrically linear or non‐linear.

This study aims to present the variations of optimal seismic control of reinforced cement concrete (RCC) structure using different structural systems. Different third-dimensional mathematical models are used to examine the responses of multistory flexibly connected frames subjected to earthquake excitations.

This paper examined a G + 50 multi-storied high-rise structure, which is analyzed using different combinations of moment resistant frames, shear walls, seismic outrigger systems and seismic dampers to observe the effectiveness during ground motion against soft soil conditions. The damping coefficients of added dampers, providing both upper and lower levels are taken into consideration. A finite element modeling and analysis is generated. Then the nature of the structure exposed to ground motion is captured with response spectrum analysis, using BNBC-2020 for four different seismic zones in Bangladesh.

The response of the structure is investigated according to the amplitude of the displacements, drifts, base shear, stiffness and torsion. The numerical results indicate that adding dampers at the base level can be the most effective against seismic control. However, placing an outrigger bracing system at the middle and top end with shear wall can be the most effective for controlling displacements and drifts.

The response of high-rise structures to seismic forces in Bangladesh’s soft soil conditions is examined at various levels in this study. This study is an original research which contributes to the knowledge to build earthquake resisting high-rises in Bangladesh.

The purpose of this paper is to present a simplified hybrid modeling (HYMOD) approach which overcomes limitations regarding computational cost and permits the simulation and prediction of the nonlinear inelastic behavior of full-scale RC structures.

The proposed HYMOD formulation was integrated in a research software ReConAn FEA and was numerically studied through the use of different numerical implementations. Then the method was used to model a full-scale two-storey RC building, in an attempt to demonstrate its numerical robustness and efficiency.

The numerical results performed demonstrate the advantages of the proposed hybrid numerical simulation for the prediction of the nonlinear ultimate limit state response of RC structures.

A new numerical modeling method based on finite element method is proposed for simulating accurately and with computational efficiency, the mechanical behavior of RC structures. Currently 3D detailed methods are used to model single structural members or small parts of RC structures. The proposed method overcomes the above constraints.

The aim of the study is to provide a comprehensive understanding of interrelations of structural systems and main planning considerations in supertall buildings (≥300 m).

Data were collected from 140 contemporary supertall towers using the case study method to analyze structural systems in the light of the key design considerations to contribute to the creation of more viable supertall building projects.

Central core typology, outriggered frame system, composite material and tapered prismatic and free forms were the most preferred features in supertall building design. Shear walled frame and tube systems occurred mostly in the 300–400 m height range, while outriggered frame systems were in the range of 300–600 m in height. Asia, the Middle East and North America mainly preferred outriggered frame systems, followed by tube systems. Considering the building function and form, the most preferred structural system in each of these groups was outriggered frame system, while mixed-use function stood out in all structural systems except in shear walled frame system.

To date, there has been no comprehensive study in the literature of the interrelations of structural systems and important planning considerations in the design of contemporary supertall towers through a large set of study samples. This critical issue was multidimensionally explored in this paper in light of 140 detailed case studies of supertall buildings around the world.

This paper aims to investigate the level of awareness about, adoption of and willingness to adopt light steel (LS) for building projects. It also assessed the benefits, challenges and solutions to the challenges of adopting LS for building projects.

The quantitative (questionnaire) research method was used for the study. The research design was survey in nature. The whole-population cluster sampling technique was adopted. The clusters were the LS buildings from two (Western Cape and Gauteng) out of the eight provinces in South Africa. The respondents were the construction organizations that have executed LS building projects in the selected provinces. Hence, 56 firms filled and returned the questionnaire. Data analysis was done with frequency, mean scores, t-test and analysis of variance (normality of data distribution assumed).

Results indicated that, out of the 29 areas of application of LS identified in literature, respondents were aware of 11 areas, adopted LS for seven areas and were willing to adopt LS for six areas. Respondents also noted that 18 of the 25 identified benefits of LS were relevant to South Africa. Despite the benefits, few developers embrace it, it is a threat to suppliers’ and contractors’ businesses and it delays building approval due to low awareness.

The implication of the results is that there is low awareness about, adoption of and willingness to adopt LS for building projects in South Africa, and this may be due to the identified challenges. To boost the awareness about, adoption of and willingness to adopt LS, LS technologies need to be imported, LS warehouses should be provided in all cities and it must be ensured that LS building projects are cheaper than conventional buildings.

The value of the study is that the adoption of LS for building projects will improve the capacity of sustainable development.

This paper aims to study the lateral behavior of cold-formed steel walls with K-shaped bracing by finite element modeling.

The braces which have the same section as those for studs and tracks are connected to the frame by screw connections. By pushover analysis, lateral performance of two frame categories, with different dimensions and bracing arrangements, is examined, and the force-displacement diagram and the ultimate strength of walls are extracted. Probable failure modes during lateral loading including distortional buckling of studs, buckling in braces and failure of connections are simulated in the numerical model, and some strengthening suggestions would be offered to prevent brittle failures and, therefore, to increase the lateral strength of the walls.

The strengthened walls are examined, and their seismic behavior is compared with the original walls. Finally, a parametric study is carried out to evaluate the effect of factors such as thickness of frame members, frame height and yield tension of members on lateral behavior of the shear walls.

In the present research, lateral strength and failure modes of nine types of cold-formed steel shear walls with different arrangements of K-shaped bracing are examined by non-linear finite element analysis, and a parametric study is carried out to extract the effect of the wall frame characteristics on the lateral behavior. Shear walls are classified into two series.

The purpose of this paper is to present eight local elasto‐plastic beam element formulations incorporated into the corotational framework for two‐noded three‐dimensional beams. These formulations capture the warping torsional effects of open cross‐sections and are suitable for the analysis of the nonlinear buckling and post‐buckling of thin‐walled frames with generic cross‐sections. The paper highlights the similarities and discrepancies between the different local element formulations. The primary goal of this study is to compare all the local element formulations in terms of accuracy, efficiency and CPU‐running time.

The definition of the corotational framework for a two‐noded three‐dimensional beam element is presented, based upon the works of Battini .The definitions of the local element kinematics and displacements shape functions are developed based on both Timoshenko and Bernoulli assumptions, and considering low‐order as well as higher‐order terms in the second‐order approximation of the Green‐Lagrange strains. Element forces interpolations and generalized stress resultant vectors are then presented for both mixed‐based Timoshenko and Bernoulli formulations. Subsequently, the local internal force vector and tangent stiffness matrix are derived using the principle of virtual work for displacement‐based elements and the two‐field Hellinger‐Reissner assumed stress variational principle for mixed‐based formulations, respectively. A full comparison and assessment of the different local element models are performed by means of several numerical examples.

In this study, it is shown that the higher order elements are more accurate than the low‐order ones, and that the use of the higher order mixed‐based Bernoulli element seems to require the least number of FEs to accurately model the structural behavior, and therefore allows some reduction of the CPU time compared to the other converged solutions; where a larger number of elements are needed to efficiently discretize the structure.

The paper reports computation times for each model in order to assess their relative efficiency. The effect of the numbers of Gauss points along the element length and within the cross‐section are also investigated.

Several studies were made on paired site and soil–structure interaction (SSI) effects, but most of them were site specific. This paper aims to investigate the impact of SSI effects in conjunction with local soil condition effects on the seismic response of typical multistory low- to mid-rise–reinforced concrete (RC) buildings resting on Algerian regulatory design sites through a global explicit transfer function (TF).

A preliminary quantification of SSI effects associated with site effects is carried out through a frequency-domain solution based on the concept of rock-to-soil surface displacement TF performed for each design site category. It results from the combination of the TFs of structure, foundation and soil and reflects how seismic waves are amplified due to changes in the geological contrast between the rock and overlying soil deposits. As well, response modification factors, denoting displacement ratios of the building responses within the flexible and site-structure conditions with respect to the fixed-base one, are carried out.

In the context of Algerian seismic regulation, the study provides a clear vision of how and when site or SSI effects are expected to be influential, as opposed to the fixed-base hypothesis still retained by the current regulation. This helps engineers to be aware of the extent of the expected seismic damage.

The research applies to low- to mid-rise RC buildings within the Algerian seismic regulation, but it may also be expanded to other examples that fall under other seismic regulations.

The response modification ratio is a quantitative approach to assessing response fluctuations. It draws attention to how the roof level drift varies depending on the condition. These results can be used as numerical parameters in structural seismic design when the structure is comparable because they provide useful information about how the two phenomena interact with the structure.

The study goes beyond particular situations dealing with site specific and offers effective indicators and quantitative evaluation of combined site and SSI effects according to the current national seismic provisions, where no indication about site or SSI effects exists.