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Buckling-restrained brace frames (BRBFs) have been a popular seismic force-resisting system in the US since it was first introduced to the AISC Seismic Provisions and ASCE 7 in 2005. The st...

The friction behavior of mortar–polymer–steel debonding interfaces was experimentally investigated to support numerical simulation of buckling-restrained braces (BRBs). Characteristic conta...

To better understand the mechanical behavior of cold-formed steel (CFS) quadruple-limb built-up box-section (QBB) columns associated with flexural buckling, 12 axial compression tests with ...

A finite-element formulation is presented for the elastic distortional buckling analysis of doubly symmetric wide flange beams. The formulation characterizes the distribution of the lateral...

Buckling-restrained braces (BRBs) are seismic devices that provide structures such as buildings and bridges with lateral support, dissipating more energy than traditional bracing. Large-sca...

This paper presents a computationally efficient formulation based on group theory, for the buckling analysis of symmetric plane frames. Numerical examples ranging from simple frames with on...

To investigate the performance of reinforced-concrete frames with buckling restrained braces (RCF-BRB) subjected to bidirectional earthquakes, a full-scale two-story RCF-BRB was tested usin...

A strong mainshock may cause several aftershocks within a short interval. These aftershocks can make buildings damaged during the mainshock more vulnerable to collapse. Hence, it is critica...

In this paper, an experimental program is presented consisting of 13 experiments on welded stainless steel I-profile beams subjected to lateral torsional buckling, in which 11 specimens are made of the lean duplex stainless grades EN 1.4062 and EN 1.4162, while the last two specimens are made of the austenitic grade EN 1.4404. The beam heights are 160, 210, and 260 mm, and the beams have a constant flange width of 160 mm. This results in three different strong axis elastic section moduli but similar weak axis bending resistances. The range of beam buckling length covers slenderness values from 0.30 to 0.76. The geometrical imperfections of the specimens were measured using digital image correlation (DIC). The web was first measured along its whole length. Then, the beam was placed on its fork supports, and the imperfection was then remeasured once more to check the influence of both gravity and test setup. Traditional four-point bending tests were carried out, and during which, the displacements were measured using linear variable differential transformer (LVDTs), inclinometers, and DIC. In this paper, the measured ultimate moments, together with results of experiments collected in the literature, are compared to the design rules provided in EN 1993-1-4, for which a safe but rather conservative design is obtained, and to the recent proposal of Taras and Greiner dedicated to carbon steel beams. The latter provides better results for high slenderness values but can be further improved.

Corrosion affects the sustainability of steel structures, especially those with improper maintenance and those exposed directly to the atmosphere and seashore environments. Corrosion-relate...

This paper investigates the elastic lateral-torsional buckling of shear deformable circular arches of monosymmetric steel I-section with in-plane elastic rotational end constraints under a ...

To investigate the performance of a RC frame with buckling-restrained braces (RCF-BRB) subjected to bidirectional earthquakes, a full-scale two-story RCF-BRB was tested using substructural ...

Flexural buckling is one of the main problems steel structures are faced with in ensuring an economic design. In Europe, the buckling resistance is calculated using an imperfection factor b...

Steel beam-columns subjected to cyclic loading (such as during earthquakes) may exhibit local buckling, which results in effective cross-sectional softening and localization of deformation. These phenomena are critical from the standpoint of performance and collapse assessment. Fiber-based elements are attractive for simulating beam-column response because they capture P-M interactions and the spread of plasticity and can be generalized to different cross sections from material-level calibrations. However, conventional fiber models typically employ softening constitutive material laws to represent local buckling. Without a regularizing length scale, this results in a nonelliptic boundary-value problem, leading to severe mesh dependence. A two-dimensional nonlocal fiber-based beam-column model is presented to address this issue for steel wide-flange sections subject to combinations of axial and cyclic lateral loads. The methodology includes the following elements: (1) a constitutive material model that is able to represent inelastic cyclic local buckling, (2) a nonlocal strain formulation that incorporates a physically based length scale, and (3) suggested practices for input selection and parameter calibration. Forty-two continuum finite-element models (encompassing a range of parameters including cross section, axial load ratio, moment gradient, and loading history) are constructed to inform as well as validate the presented methodology. The methodology simulates various aspects (loaddeformation response, localized deformation, and column axial shortening) with accuracy and without mesh dependence. This is in contrast to conventional fiber models that exhibit severe mesh dependence. Limitations are discussed.

The beam-truss model (BTM), developed for the nonlinear cyclic analysis of reinforced concrete components including softening, is extended to compute the out-of-plane buckling observed in p...

Guidance for the lateral-torsional buckling behavior of singly-symmetric, nonprismatic (stepped flanges) sections are often absent from design specifications or are overly simplified. This ...

The strength of cold-formed steel beams with stiffened flanges may be controlled by distortional buckling. Buckling stress prediction methods have been developed for flanges under uniform c...

Narrow width I-girder systems with relatively long lengths are susceptible to global lateral-torsional buckling, which is a mode that is not generally sensitive to the spacing between cross...

Lip stiffened flanges in cold-formed steel compression members may undergo local or distortional buckling depending on the slenderness of the flange and rigidity of the lip. In distortional...

An experimental investigation was conducted to assess the performance of a new buckling-restrained brace (BRB) system for retrofitting seismically deficient reinforced concrete frames. The ...

During earthquakes, I-shaped beams (I-beams) in a braced structure are subjected to the flexural moment synchronized with reversed axial forces transmitted from buckling restrained braces. ...

The grooved-type dissipater is an axial, metal hysteretic dissipative device. It is an alternative to the epoxy- or grout-filled buckling restrained fuse (BRF)-type dissipater. This device ...

An integrated strategy for sizing and shape optimization of truss structures, taking buckling constraints implicitly into truss design, is demonstrated here. Because the associated objectiv...

Buckling analysis of spherical concrete domes constructed over prestressed concrete tanks subjected to gravity and earthquake load combinations is complex due to the sensitivity of spherica...

This paper focuses on local buckling and axial compressive behavior of steel-plate composite (SC) walls. SC walls are comprised of a concrete wall sandwiched between two steel faceplates on...

Generally speaking, steel beams are mechanically assembled with a concrete slab and stud shear connectors. The concrete slab works as a restraint against buckling instability such as latera...

In this study, the pressure-displacement equilibrium path and the elastic buckling pressure were formulated analytically for a thin-walled circular liner encased in a partially grouted pipe...

In this study, the buckling-resistant antispring-clad reinforcing bar (BRASR) for improving the performance of the longitudinal reinforcing bars embedded in concrete columns is presented. B...

Two groups of geometrically identical buckling-restrained braces (BRBs) were subjected to either dynamic or quasi-static uniaxial loading until the cores fractured to investigate the effect...

Shear-acting structural fuses rely on steel plates subjected to in-plane lateral displacements that dissipate energy through shear yielding or may have cutouts that result in shear or flexu...

Concentrically braced frames (CBFs) are commonly used in steel building structures to rapidly increase structural stiffness, especially in high seismic regions. However, conventional buckli...

Development and implementation of horizontally curved steel members, particularly curved plate girders utilized by the bridge industry for complicated site geometries, continue to occur, an...

Designers favor laminated glass due to its inherent robustness. However, there is disparity between the various design codes currently available for laminated glass and the methods therein ...

This paper concentrates on the laterally flexural-torsional buckling analysis incorporating shear deformations for elastic steel circular arches having boundary rotational restraints under ...

The present study investigated the effect of web distortion on the lateral torsional buckling strength of Gerber systems. Toward this goal, a number of modifications were introduced into tw...

This paper proposes the use of an additional stiffening ring to prevent buckling of aboveground storage tanks (ASTs) under storm-surge inundation and presents an approach to obtain an optim...

Steel-concrete-steel (SCS) composite structures with bidirectional steel webs and ribs exhibit superior performance in capacity, rigidity, ductility, blast resistance, waterproofness, and c...

Fiber-based elements are commonly used to simulate steel beam-columns because of their ability to capture P-M interactions and spread of plasticity. However, when mechanisms such as local buckling result in effective softening at the fiber scale, conventional fiber models exhibit mesh dependence. To address this, a two-dimensional (2D) nonlocal fiber-based beam-column model is developed and implemented numerically. The model focuses on hot-rolled wide flange sections (W-sections) that exhibit local buckling-induced softening when subjected to combinations of axial compression and flexure. The formulation upscales a previously developed nonlocal formulation for single-fiber buckling to the full frame element. The formulation incorporates a physical length scale associated with local buckling along with an effective softening constitutive relationship at the fiber level. To support these aspects of the model, 43 continuum finite element (CFE) test problems are constructed. These test problems examine a range of parameters, including the axial load, cross section, and moment gradient. The implemented formulation is validated against CFE models as well as physical steel beam-column experiments that exhibit local buckling-nduced softening. The formulation successfully predicts postpeak response for these validation cases in a mesh-independent manner , while also capturing the effects of P-M interactions and moment gradient. To enable convenient generalization, guidelines for calibration and selection of the model parameters are provided. Limitations are discussed along with areas for future development.

This research focuses on a new type of buckling-restrained brace (BRB) with replaceable steel angle fuses. The proposed BRB offers ease of postearthquake examination of fuse damage, conveni...

The conventional restraining ratio approach is not suitable for a straightforward design of the pre-tensioned cable-stayed buckling-restrained brace (PCS-BRB) because of its complicated buc...

This paper presents a comprehensive experimental and numerical study on distortional buckling–moment resistance capacity of built-up cold-formed steel hybrid double-I-box beams (HDIBBs) und...

Little research has been reported for the out-plane elastic-plastic buckling strength of high-strength steel (HSS) arches and no adequate code provisions are available for their strength de...

Quasi-static experiments were conducted to subject buckling restrained braces (BRBs) to a regime of relative end displacements demands to investigate if the BRBs’ end connections could be a...

The strength of thin-walled cold formed steel (CFS) lipped channel compression members may be governed by yielding, local, distortional, or global buckling or any possible interaction among...

The existing design expressions for the lateral-torsional buckling behavior of castellated beams conflict. Furthermore, they do not take into account the detrimental effect of the residual stress modification attributable to the fabrication process, which was only recently demonstrated by the authors. This makes these design rules possibly unsafe. In this paper, the lateral-torsional buckling behavior of doubly symmetric castellated beams loaded by a constant bending moment is investigated numerically. The numerical model, including the modified residual stresses, was validated by comparing its results with experimental results. A preliminary design approach is proposed based on the current European guidelines for the calculation of the lateral-torsional buckling resistance of I-section beams. According to the proposed approach, the lateral-torsional buckling resistance of castellated beams can be determined using the cross-sectional properties calculated at the center of the web opening. The modi...

This paper proposes a general approach for topology optimization of tensegrity structures. The optimization problem is formulated in the framework of a mixed-integer linear programming. Com...

Current standards require that, for moment-resisting frames, the strength degradation of a beam–column connection should not reduce flexural strength measured at a drift angle of 0.04 rad t...

Laboratory tests have shown that current standardized design rules lead to overly optimistic results for calculated ultimate loads of plated structures, especially for internal elements suc...