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This paper aims to study, the effects of opening shape, size and position as well as the aspect (height-to-length) ratio on the shear capacity, stiffness, ductility and energy dissipation capacity of triple-skin profiled steel-concrete composite shear wall (TSCSW) and investigate and compare them to those of concrete-stiffened steel plate shear walls (CSPSW). Two kinds of opening, circular and square, with different sizes and positions and two aspect ratios of 1:1 and 3:1 are considered in the simulations.

This study presents a novel TSCSW and compares its behavior with the existing CSPSW under the effect of monotonic and cyclic loadings. TSCSW is composed of three corrugated steel plates filled with concrete. The two external side plates are connected to the concrete core by means of several intermediate fasteners and the third one is an inner steel plate embedded within the concrete panel. The internal plate is a buckling restrained plate surrounded by concrete. This is the main superiority of TSCSW over other kinds of existing composite shear walls.

The results show that the shear capacity and the energy dissipation capacity of the proposed composite wall, TSCSW, are respectively about 16 and 12% higher than those of CSPSW when there is no opening. If an opening is considered in the wall, as the size of the opening is increased, the shear capacity, stiffness, ductility and absorbed energy of the two walls are decreased similarly. The destructive effect of square openings on the performance of the walls is more than that of circular openings.

This is an original work.

Aiming at the characteristics of large stiffness, low ductility, and poor energy dissipation capacity of cross-laminated timber (CLT) shear wall, a method of opening vertical joints and adding low-yield dampers in CLT shear wall is proposed to improve its energy dissipation capacity and ductility.

The finite element model of CLT shear walls with low-yield dampers and dampers assembly was established by ABAQUS. The structural shape of low-yield dampers that meet the requirements of vertical joints in CLT shear walls is studied by numerical analysis. The influence of the number and position of low-yield dampers on the energy dissipation of the shear wall system is studied.

The results show that the low-yield damper with diamond openings should be used in the CLT shear wall, and the energy dissipation effect is the best when the CLT shear wall is uniformly covered with low-yield dampers. After the uniform arrangement of four groups of low-yield steel dampers, the energy consumption of the CLT shear wall increases by 75.38%, and the ductility increases by 13.22%.

There are few studies on replacing connectors between shear walls with low-yield steel dampers, and rectangular soft steel dampers are prone to stress concentration and poor deformation capacity. Therefore, this paper establishes the model of perforated low-yield damper and CLT and makes numerical analysis to determine the opening form, geometric parameters of low-yield damper, and the optimal layout scheme in CLT shear wall.

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.

Steel shear walls have recently received exclusive remark. Respective of most building code requirements, design of shear wall vertical boundary elements (VBEs) and local boundary elements (LBEs) against web yielding triggers exaggerated stiffness. The extent of stiffness reduction effects in boundary elements thus calls for more exhaustive investigation. The paper aims to discuss these issues.

To this end, FEM-based push-over curves demonstrating base shear vs roof displacement, and von Mises plastic strains were scrutinized in half-scale and full-size models. Analyses were in perfect conformity with experimental data.

With reference to the AISC requirement, up to 35 percent decrease in the VBE moments of inertia could be imparted in higher levels without the ultimate load capacity nor displacement to failure being reduced. Also considered was open shear walls with reduced or minimum-design LBEs, the latter being used in continuous or abridged form. LBEs could be used with a moment of inertia 80 percent smaller than required if only used in a continuous form. The effect due to opening geometry was negligible on loading capacity but distinguished on the post-yielding buckling-induced softening.

Light-weight design of low- to medium-level steel structures against earthquake loads.

With respect to continuous walls, the results are more comprehensive than those existing in the literature in that they combine the effects due to scale and orientation (horizontal or vertical) of boundary elements. The results for open shear walls are not only comprehensive but also original in a sense that they account for the influences induced by the opening type (door or window), orientation (horizontal or vertical), and design (full-length or abridged) of boundary elements, in reduced form, on the lateral stiffness of the frame.

The purpose of this paper is to provide the research and practising engineers with insight on the benefits of using low‐yield point steel with respect to ordinary steel as a construction material for shear wall panels. The paper seeks to focus on the behaviour of such panels when installed in new or existing structures in order to improve their seismic performance.

Finite element models are applied in order to approximate the structural response of low‐yield steel panels, used for seismic applications. Owing to the specific characteristics of the problem at hand, geometric and material nonlinearities have to be accurately considered. For comparison reasons, low‐yield point steel and ordinary steel are considered as construction materials for the aforementioned panels. The paper examines both the case of “pure shear” steel panel and also the more realistic case that the panel is encased in the surrounding frame.

The paper reaches a number of interesting conclusions. The beneficial behaviour of low‐yield steel panels with respect to ordinary steel panels is verified. Comments are made distinguishing the differences in the behaviour of panels surrounded by strong elements (“encased” panels) compared with that of panels submitted to pure shear. Finally, the improved seismic behaviour of existing structures retrofitted by shear wall panels is verified.

The paper exhibits numerically the advantages of low‐yield point steel with respect to ordinary steel as a construction material for panels and, second, contributes to the comprehension of the realistic panel behaviour of encased panels. More specifically, the paper focuses on the differences in the behaviour of encased steel panels with respect to the “pure shear” steel panels.

In this study, the application of a novel combined steel curved damper (SCD) and steel plate shear wall (SPSW) system in the 5-, 10- and 15-storey steel moment-resisting frames (SMR) subjected to earthquake excitation has been investigated. The proposed system is called here as the SMR-WD (steel moment resisting–wall damper).

At the beginning of this research, an SMR-W and an SMR-D are separately modeled in ABAQUS software and verified against the available experimental data. After that, three different heights SMR-WD systems (5-, 10- and 15-storey) are designed and simulated. Then, their performances are examined and compared to the corresponding SMR-W under the effects of six actual earthquake records.

The obtained results show that the proposed system increases the mean values of the base shear for 5-, 10- and 15-storey SMR-WD equal to 27, 20.15 and 16.51%, respectively compared to the corresponding SMR-W. Moreover, this system reduces the drift of the floors so that the reduction in the average values of maximum drift for 5-, 10- and 15-storey SMR-WD is equal to 10, 7 and 29%, respectively with respect to the corresponding SMR-W. The results also reveal that the considered system dissipates more energy than SMR-W so that the increase in the mean values of the energy absorption for 5-, 10- and 15-storey SMR-WD is 30.8, 25.6 and 41.3%, respectively when compared to the SMR-W. Furthermore, it is observed that SMR-WD has a positive effect on the seismic performance of the link beams and panel zones of the frames. By increasing the height of the structure in the SMR-WD, the energy dissipation and base shear force increases and the drift of floors decreases. Hereupon, the proposed SMR-WD system is more useful for tall buildings than SMR-W frames.

For the first time, the application of a novel combined steel curved damper (SCD) and steel plate shear wall (SPSW) system in the 5-, 10- and 15-storey steel moment-resisting frames (SMR) subjected to earthquake excitation has been investigated.

The purpose of this paper is to study the seismic performance of the energy-saving block and invisible multi-ribbed frame composite walls (EBIMFCW), changing the shear-span ratio as the test parameter, the low-cycle reciprocating loading tests of six 1/2 scale wall models were carried out.

The test design method and analysis are used for the seismic performance of the EBIMFCW.

With the increase of shear-span ratio: the walls tend to occur bending failure even more, the initial stiffness of the wall decreases, the overall ductility of the wall is improved and the walls tend to occur bending failure.

The previous studies do not involve the seismic performance of EBIMFCW under different shear-span ratios. Therefore, the paper studies the hysteresis behavior, ductility, stiffness degradation and energy dissipation performance of EBIMFCW under different shear-span ratios.

Based on the weak seismic performance and low ductility of coupled shear walls, engineered cementitious composites (ECC) is utilized to strengthen it to solve the deformation problem in tall buildings more effectively and study its mechanical properties more deeply.

The properties of reinforced concrete coupled shear wall (RCCSW) and reinforced ECC coupled shear wall (RECSW) have been studied by numerical simulation, which is in good agreement with the experimental results. The reliability of the finite element model is verified. On this basis, a detailed parameter study is carried out, including the strength and reinforcement ratio of longitudinal rebar, the placement height of ECC in the wall limb and the position of ECC connecting beams. The study indexes include failure mode and the skeleton curve.

The results suggest that the bearing capacity of RECSW is significantly affected by the ratio of longitudinal rebar. When the ratio of longitudinal rebar increases from 0.47% to 3.35%, the bearing capacity of RECSW increases from 250 kN to 303 kN, an increase of 21%. The strength of longitudinal rebar has little influence on the bearing capacity of RECSW. When the strength of the longitudinal rebar increases, the bearing capacity of RECSW increases little. The failure mode of RECSW can be improved by lowering the casting height of the ECC beam in a certain range.

In this paper, ECC is used to strengthen the coupled shear wall, and the accuracy of the finite element model is verified from the failure mode and skeleton curve. On this basis, the casting height of the ECC casting wall limb, the strength and reinforcement ratio of longitudinal rebar and the position of the ECC beam are studied in detail.

The purpose of this study is to improve the lateral capacity of Cold-Formed Steel (CFS) frame walls filled with lightweight foamed concrete (LFC) and supported with straw boards by introducing structural foamed concrete and/or bracing.

Finite element models are developed and calibrated based on previous experimental work. Then, these models are extended to conduct a parametric study to quantify the effect of filling CFS walls and structural LFC and the effect of supporting CFS walls with bracing.

Results of the study conclude that the finite element analysis can be used to simulate and analyze the lateral capacity of CFS walls effectively since the maximum deviation between calibrated and experimental results is 10%. The structural LFC usage in CFS walls improves the lateral capacity considerably by (25–75) % depending on the wall properties. Besides, the application of lateral bracing does not always have a positive effect on the lateral performance of these walls.

Although CFS walls are preferred due to it is light in weight, low in cost, easy to install and recyclable, low seismic performance, buckling vulnerability, poor thermal insulation and sound insulation properties, low lateral stiffness, and low shear strength limit their use. This study proposes the use of structural foamed concrete and a different bracing method than what is available in the literature. This can overcome the drawbacks of the CFS walls alone which can permit the usage of such walls in mid-rise buildings and other applications.

The high heat induced by fire can substantially decrease the load-bearing capacity, which is more critical in unprotected steel structures than concrete reinforced structures. One of the conventional steel structures is a steel-plate shear wall (SPSW) in which thin infill steel plates are used to resist against the lateral loads. Due to the small thickness of infill plates, high heat seems to dramatically influence the lateral load-bearing capacity of this type of structures. Therefore, this study aims to provide an investigation into the performance of SPSW with reduced beam section at high temperature.

In the present paper, to examine the seismic performance of SPSW at high temperature, 48 single-span single-story steel frames equipped with steel plates with the thicknesses of 2.64 mm, 5 mm and 7 mm and yield stresses of 85 MPa, 165 MPa, 256 MPa and 300 MPa were numerically modeled. Furthermore, their behavioral indices, namely, strength, stiffness, ductility and hysteresis behavior, were studied at the temperatures of 20, 458, 642 and 917? The simulated models in the present paper are based on the experimental specimen presented by Vian and Bruneau (2004).

The obtained results revealed that the high heat harshly diminishes the seismic performance of SPSW so that the lateral strength is reduced even by 95% at substantially high temperatures. Therefore, SPSW starts losing its strength and stiffness at high temperature such that it completely loses its capacity of strength, stiffness and energy dissipation at the temperature of 917? Moreover, it was proved that by separating the percentage of their participations variations of the infill plate in SPSW, their behavior and the bare frame can be examined even at high temperatures.

To the best of the authors’ knowledge, the seismic performance of SPSW at different temperatures has not been evaluated and compared yet.