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Concrete-infilled double steel corrugated-plate walls (CDSCWs) are composed of two steel corrugated-plates (SCPs) which are connected through bolts, and concrete filled the spacing formed between the two SCPs. Two vertical boundary elements are installed additionally at both sides of CDSCWs. On the one hand, the corrugated configuration of SCPs has great improvement on the load-bearing efficiency of CDSCWs; on the other hand, much higher bearing capacities and better seismic performance for CDSCWs are provided owing to the interactions among SCPs, bolts and infilled-concrete. This paper investigates the load-bearing mechanism and strength design formulae of CDSCWs under compressions. Since SCPs are prone to local buckling failure between two rows of bolts under the conditions of large vertical bolt spacing and small thickness of SCPs, this paper mainly focuses on the load-bearing mechanism of SCPs in CDSCWs under uniform compressions. The unilateral constraint on SCPs provided from infilled-concrete and the restraining effect on the flexural deformation of SCPs owing to bolts are considered. At first, series of finite element (FE) eigenvalue buckling analyses are conducted to study the elastic buckling behavior of SCPs subjected to uniform compressions. On the basis of Euler's formula, the formulae for predicting the elastic buckling stresses and corresponding normalized slenderness ratios λs of SCPs are achieved respectively. The instability performance of SCPs under uniform compressions is then investigated through FE nonlinear analyses, and accordingly the stability coefficient φs is attained. The corresponding φs−λs curve is therefore established in order to calculate the ultimate bearing capacities of SCPs. In addition, the cooperative performance of material strengths between SCPs and concrete is analyzed numerically when CDSCWs reach their compressive ultimate strength. With this consideration, the design method for predicting the cross-sectional strength of CDSCWs under compressions is proposed. Moreover, a CDSCW specimen with I-section is tested under a compressive load. Its cross-sectional strength is investigated experimentally. The results of the experiment coincide with those of numerical simulation, this verifying the safety and validity of the design method for cross-sectional strength design of CDSCWs.

In this paper, a double-corrugated-plate shear wall (DCPSW) is proposed. It consists of two trapezoidally corrugated plates connected with high-strength bolts. It could be utilized in high-rise buildings as an alternative of the ordinary corrugated plate shear wall (CPSW) to resist lateral shear loads resulting from horizontal seismic or wind effects. In this paper, the elastic buckling behavior of DCPSWs subjected to pure in-plane shear loads is of major concern and is firstly investigated. The DCPSWs are equivalent into orthotropic plates, and accordingly, the rigidity constants, including flexural rigidity constants in the orthotropic directions ( D x and D y ) and the torsional rigidity constant ( H ), are defined and theoretically derived. By comparing the theoretical formulas of the rigidity constants with the results obtained from finite element (FE) eigenvalue buckling analyses, these theoretical formulas are validated to be accurate enough for practical engineering applications. Then, the shear elastic buckling formulas of the DCPSWs are provided by means of FE analyses and numerical fitting technique, and these formulas are validated to be able to conservatively predict the shear elastic buckling loads of DCPSWs with good accuracy. Finally, the shear-resistant behavior of the DCPSWs is investigated via a parametric study of FE models subjected to monotonic shear loads. It is concluded that the normalized aspect ratio could be regarded as a comprehensive design parameter which reflects the ultimate shear resistance of the DCPSW.

This paper proposes a new type of composite walls, namely concrete-infilled double steel corrugated-plate walls (CDSCWs). The CDSCW consists of a wall element that is formed by two steel corrugated-plates, where they are interconnected through high-strength bolts, and the spacing between the two steel corrugated-plates is filled with concrete. Additionally, two concrete-infilled steel tubes (CFSTs) are assigned as vertical boundary elements at both sides of the wall element. Not only the corrugated configuration of steel sheets themselves would significantly improve the load-bearing efficiency of CDSCWs, but also the interactions and combined actions among steel corrugated-plates, high-strength bolts and concrete could provide much better load-bearing capacity and seismic performance for CDSCWs. In addition, industrial mass production of the CDSCWs can be achieved by adopting integrated cold-formed steel rolling techniques. Therefore, the CDSCWs are much more suitable for applications in high-rise building structures as shear wall structural systems that carry axial loads and bending moments as well as shear loads. This paper mainly investigates the overall instability performance of I-section CDSCWs under uniform compressions and corresponding design formulae are recommended. Firstly, Finite Element (FE) eigenvalue buckling analyses are carried out to investigate the overall elastic buckling behavior of CDSCWs subjected to vertical compressive loads. The formulae for estimating the elastic buckling loads of CDSCWs and corresponding normalized slenderness ratios λn are obtained based upon the form of Euler's formula. The overall instability performance of CDSCWs under compressions is then studied by FE nonlinear analyses, leading to the overall stability coefficient φ as well as φ-λn curve for their strength design. Moreover, an I-section CDSCW specimen has been designed and tested under uniform compressive load, and its overall instability performance is investigated experimentally. The results obtained from the experiment show an agreement with those obtained from FE numerical analyses, which also verifies the safety and validity of φ-λn curves for the strength design of CDSCWs.

In recent years, the steel corrugated shear walls (SCSWs) are widely used in building structures to serve as lateral force resistant members. For some practical engineering applications that the width of the infilled SCSWs in frame structure is much greater than its height, it is common to add vertical stiffening systems to the SCSWs, thus forming the stiffened SCSWs (SSCSWs), and the stiffening system is composed of a pair of vertical stiffeners installed on both sides of the corrugated plate and the connecting high-strength bolts. In this paper, the shear resistant behavior of the SSCSWs is investigated via FE analyses considering both the geometrical and material nonlinearities, and over 300 models are analyzed through elastoplastic numerical process. The comparison of the shear resistant behavior of SSCSWs with different stiffening rigidities is performed, which indicates that the stiffening system can effectively restrain the out-of-plane displacements of the corrugated wall, and can improve both shear resistance and ductility of the SSCSWs. Then a transition rigidity ratio of the stiffening system is proposed to reflect the critical value of the stiffening rigidity that the out-of-plane displacements of the corrugated plate are fully restrained at the bolted locations. Correspondingly, curve fitted formula of the transition rigidity ratio is provided to enable a conservative prediction. Finally, shear buckling formulas are fitted to reveal the relationship between the reduction factor and the normalized aspect ratio, and they are validated to be able to conservatively predict the ultimate shear stress of SSCSWs. Accordingly, some design recommendations are presented, which could provide valuable references for practical design of SSCSWs.

The concrete-infilled double steel corrugated-plate walls (CDSCWs) consist of two steel corrugated plates (SCPs), infilled concrete and two boundary elements. The two SCPs are connected by high-strength bolts and the spacing between the two SCPs is filled with concrete. The two vertical boundary elements are installed at both sides of CDSCWs. The sectional load-bearing performance of CDSCWs only under uniform compression has been investigated previously by the authors. But CDSCWs under a combination of compression and in-plane bending moment are applied in practice widely and commonly. Therefore, this paper presents the corresponding sectional load-capacity design method of CDSCWs under a combination of compression and in-plane bending moment. Firstly, an experimental investigation on sectional load-capacity of an I-shaped CDSCW specimen subjected to combined compression and in-plane bending moment is completed. The experimental results reveal a high axial load-bearing efficiency of the SCPs in the CDSCW specimen, and also validated the finite element (FE) model adopted in this study. Then, the FE numerical simulation is applied to systematically analyze the load-bearing performance of CDSCWs subjected to the combination of compression and in-plane bending moment. The coefficient φsp is introduced to consider the local buckling of compressive zone and the weakening effect of tensile-compressive transition zone in SCPs. The coefficient βc is introduced to consider the weakening effect of tensile-compressive transition zone in concrete and the adverse cooperative effect among SCPs, concrete and boundary elements owing to their different ultimate strains at the ultimate state of CDSCWs. As a result, the N-M correlation curve for predicting the sectional load-bearing capacity of CDSCWs under both the uniform compression and in-plane bending moment is then established and also verified by the experimental results.

An effective way for improving the global load-carrying capacity of a steel arch with a welded hollow section is to increase the height of its webs. However, the high and thin web may buckle locally, which will affect the global load-carrying capacity and should be taken into account in predicting the global strength of the arch. This paper presents a numerical investigation for the in-plane strength and design for pin-ended circular steel arches with a welded hollow section, focusing on the effects of web local buckling by the large deformation inelastic analysis in association with a finite shell element model. The circular steel arches subjected to a radial load uniformly distributed along the arch length, a load uniformly distributed over the full span of the arch, or/and over the half span of the arch and their various combinations are considered in the investigation of their failure modes and strengths. The initial global and local geometric imperfections as well as residual stresses are included in the finite element model. It is found that web local buckling influences the global strength of the steel arches significantly and needs to be accounted in formulate their strength design formulas. The parameters related to the web local buckling and global buckling of the arch are thoroughly explored. It is found that the stability coefficients of arches under the nominal uniform axial compression are related to the equivalent normalized web height-to-thickness ratio of the cross-section and the normalized slenderness of the arch, and accordingly the design formula of the stability coefficients is proposed by including their effects. In addition, a design formula for predicting the strengths of the arches under a load uniformly distributed over the full span is developed by introducing a corrective coefficient into the stability coefficient, and it is found that the corrective coefficient is related to the arch rise-to-span ratio and slenderness of the arch. Furthermore, a general interaction design formula is developed for predicting in-plane strength of the arches under general in-plane loading such as a load uniformly distributed over the half span of the arch and various combinations of a full span uniform load and a half span uniform load. Comparisons with the finite element results demonstrate the proposed design formulas can provide good predictions and/or lower bound predictions for the strengths of the steel arches with a welded hollow section.

This paper investigates the elastic buckling behavior of steel trapezoidal corrugated shear walls (STCSWs) with vertical stiffeners. On the basis of an orthotropic plate model, by utilizing the theorem of minimum potential energy and the Ritz method, the buckling loads of stiffened STCSWs can be precisely calculated using MATLAB. Then, a value of transition rigidity of stiffener is suggested and, hence formulas of elastic buckling coefficients of stiffened STCSWs are proposed. Finally, the verification of proposed formulas using a FE model shows that the formulas are validated and applicable in estimating the elastic buckling loads of stiffened STCSWs.

Double-corrugated-plate shear wall (DCPSW), which is composed of two identical corrugated plates and assembled by connecting bolts, is an innovative type of lateral force resistant device for high-rise building structures. In this paper, the shear resistant behavior of the DCPSW is investigated via tests and additional finite element (FE) parametric study. First, the test results of two DCPSW specimens subjected to monotonic in-plane shear loads are reported. Second, FE models are introduced to perform simulations on the shear resistant behavior of the test specimens; it is seen that the numerical results fit well with the test results, and hence the FE models for simulations of the DCPSWs are validated. Then, an additional parametric study is presented by changing the geometrical parameters including aspect ratio, bolt column number, corrugation amplitude and dimensions of boundary elements of the DCPSWs. As a result, the effects of these parameters on the shear resistant behavior of the DCPSWs are further revealed. It is shown that the ultimate shear resistance of the DCPSWs increases with the increase of aspect ratio, bolt column number and corrugation amplitude, yet the dimensions of the boundary elements have little effect on the shear resistance of the embedded corrugated plates. Finally, by analyzing the results of the parametric study, some design remarks are concluded to provide valuable references for the design of the DCPSWs in practice.

An elastic-plastic large-deflection finite strip method has been set up to compute the interaction behaviour of initially deflected and eccentrically loaded cold-formed thin-walled channel sections. The ultimate loads of the sections are estimated under the loading of a constant compression eccentricity and a constant load eccentricity, respectively. A series of conclusions, which are valuable for channel section design, are obtained through many numerical calculations. A test programme associated with the Moire fringe technique is performed. Comparisons of analytical and experimental results reveal that the finite strip method possesses a high accuracy in elastic-plastic large-deflection analysis of plates and sections.