Showing papers in "Journal of Structural Engineering-asce in 2017"
TL;DR: In this article, a parametric numerical study is performed involving a top-floor-TMD-equipped planar frame capturing accurately the in-plane dynamic behavior of a 74-storey benchmark building exposed to a quasi-stationary spatially-correlated wind-force field accounting for vortex shedding effects in the across-wind direction.
Abstract: In this paper the classical linear tuned mass-damper (TMD) is coupled with an inerter, a two-terminal device resisting the relative acceleration of its terminals, in various tuned mass-damper-inerter (TMDI) topologies to suppress excessive wind-induced oscillations in tall buildings causing occupants’ discomfort. A parametric numerical study is undertaken involving a top-floor-TMD-equipped planar frame capturing accurately the in-plane dynamic behavior of a 74-storey benchmark building exposed to a quasi-stationary spatially-correlated wind-force field accounting for vortex shedding effects in the across-wind direction. It is found that the TMDI reduces the peak top floor acceleration more effectively than the TMD by considering smaller attached mass values, and TMDI topologies in which the inerter spans more stories in linking the attached mass to the host structure. Moreover, the inclusion of the inerter reduces dramatically the TMD stroke while it was verified that the magnitude of the developing inerter forces can be readily accommodated by the host structure. Pertinent illustrative examples are included showcasing that the TMDI meets code-prescribed serviceability design requirements for new tall buildings using significantly smaller attached mass compared to the TMD, and that inerter devices can be used to upgrade the performance of existing TMD-equipped tall buildings without changing the attached mass.
189 citations
TL;DR: In this article, a simplified modeling strategy for seismic assessment of precast bridge columns connected to precast footings using grouted splice sleeve connectors is presented, and a computational model is developed and validated using three half-scale bridge subassemblies tested to failure.
Abstract: Reinforcing bar couplers are used in prefabricated bridge elements and bridge systems for accelerated bridge construction. Grouted splice sleeve connectors are used in bridge substructures because of the enhanced construction tolerances they offer. This paper presents a simplified modeling strategy for seismic assessment of precast bridge columns connected to precast footings using grouted splice sleeve connectors. A computational model was developed and validated using three half-scale bridge subassemblies tested to failure. Cyclic quasi-static loading was applied to two precast subassemblies and one cast-in-place specimen. The connectors were located in the footing, for the first precast alternative, and in the column end for the second precast alternative along with debonding of reinforcing bars in the footing. Force-based beam-column elements with fiber sections were used to construct the computational model based on plastic hinge weighted integration; the model included low-cycle fatigue and ...
144 citations
TL;DR: In this paper, a comprehensive review of state-of-the-art fragility and restoration models for typical highway bridge classes that are applicable for implementation in multihazard risk and resilience analyses of regional portfolios or transportation networks in the United States is presented.
Abstract: Highway bridges are one of the most vulnerable constituents of transportation networks when exposed to one or more natural hazards, such as earthquakes, hurricanes, tsunamis, and riverine floods. To facilitate and enhance prehazard and posthazard event mitigation and emergency response strategies of transportation systems and entire communities, probabilistic risk and resilience assessment methodologies have attracted increased attention recently. In this context, fragility and restoration models for highway bridges subjected to a range of hazards are essential tools for efficient and accurate quantification of risk and resilience. This paper provides a comprehensive review of state-of-the-art fragility and restoration models for typical highway bridge classes that are applicable for implementation in multihazard risk and resilience analyses of regional portfolios or transportation networks in the United States. An overview of key gaps in the literature is also presented to guide future research.
119 citations
TL;DR: In this paper, the behavior of concrete-filled steel tubular (CFST) columns can be predicted accurately using detailed finite-element (FE) modeling, but such models are tedious to build and impractical for fr...
Abstract: Behavior of concrete-filled steel tubular (CFST) columns can be predicted accurately using detailed finite-element (FE) modeling, but such models are tedious to build and impractical for fr...
107 citations
TL;DR: In this article, the authors reveal the great potential of using combined superelastic shape memory alloy (SMA) bolts and steel angles for self-centering connections with variable performance targets.
Abstract: This paper reveals the great potential of using combined superelastic shape memory alloy (SMA) bolts and steel angles for self-centering connections with variable performance targets. Eight full-scale specimens were tested, and the main parameters included SMA bolt prestrain, bolt length, angle thickness, and layout of bolts and angles. The specimens showed desired yielding sequences and deformation modes. The inelastic deformation was accommodated by the SMA bolts and angles with no damage to the column and beam. The specimens also exhibited very good self-centering abilities at 2% drift, beyond which the self-centering abilities were dependent on the considered parameters. A ductility capacity of at least 4% was provided by all the specimens. The maximum equivalent viscous damping ranged between 11 and 15%, indicating moderate energy dissipation. Following the test program, a design framework for such connections was proposed, and a calculation example was provided to further illustrate the prop...
106 citations
TL;DR: In this article, a well-instrumented drop-weight test program was developed to investigate shear failure modes of large-scale RC beams under impact loading, and test variables included beam span, transverse rei...
Abstract: A well-instrumented drop-weight test program was developed to investigate shear failure modes of large-scale RC beams under impact loading. Test variables included beam span, transverse rei...
97 citations
TL;DR: Despite successful mid-rise to high-rise timber building projects around the world, this article pointed out that "despite successful midrise-to-high-rise wood building projects, despite the success of these projects, wood is an attractive and sustainable alternative structural engineering material to concrete and steel".
Abstract: Mass timber is an attractive and sustainable alternative structural engineering material to concrete and steel. Despite successful midrise to high-rise timber building projects around the w...
74 citations
TL;DR: In this paper, the authors considered MI panels as architectural elements in progressive collapse analysis, but their weights were not considered in the progressive collapse model, but instead they were considered as structural elements.
Abstract: Masonry-infilled (MI) panels, which serve as partitions in buildings, are normally considered as architectural elements. Their weights are considered in progressive collapse analysis, but t...
74 citations
TL;DR: In this paper, a new type of replaceable steel coupling beam was developed, which consists of a central fuse shear link connecting to steel beam segments at its two ends, and a series of quasi-static tests conducted to examine the seismic behavior and replaceability of the replaceable coupling beams.
Abstract: For improving the seismic resiliency of coupled shear wall systems, a type of replaceable steel coupling beam was developed, which consists of a central “fuse” shear link connecting to steel beam segments at its two ends. Inelastic deformation is concentrated in the shear link during a severe earthquake, and the damaged links can be replaced easily as specialized link-to-beam connections are adopted. This paper presents a series of quasi-static tests conducted to examine the seismic behavior and replaceability of the replaceable coupling beams. A total of four large-scale specimens were designed and tested, where different types of beam-to-link connections were adopted, including end plate, splice plate, bolted web, and adhesive web. All specimens fully developed the shear strength of the fuse links and showed large inelastic rotation capacity of no less than 0.06 rad, except for the specimen with the adhesive web connection, which failed at an early stage. The specimen with the end plate connecti...
69 citations
TL;DR: Double-skin composite (DSC) walls consist of a thick concrete infill sandwiched in between two steel faceplates on the exterior surfaces as discussed by the authors, and are used in high-rise buildings.
Abstract: Double-skin composite (DSC) walls consist of a thick concrete infill sandwiched in between two steel faceplates on the exterior surfaces. DSC walls used in high-rise buildings have higher r...
67 citations
TL;DR: An experimental and numerical study of the flexural buckling behavior of hot-finished high-strength steel (HSS) square and rectangular hollow section (SHS and RHS) columns is presented in this paper.
Abstract: An experimental and numerical study of the flexural buckling behavior of hot-finished high-strength steel (HSS) square and rectangular hollow section (SHS and RHS, respectively) columns is ...
TL;DR: Inherent time-varying trends of wind records are frequently captured in recent field measurements of tropical cyclones as discussed by the authors, which indicate a nonstationary process that deviates from the standard model.
Abstract: Inherent time-varying trends of wind records are frequently captured in recent field measurements of tropical cyclones. These observations indicate a nonstationary process that deviates fro...
TL;DR: The shear strength (V) of reinforced concrete (RC) beams consists of two parts: shear resistance of concrete (Vc) and contribution of the transverse reinforcement (Vs).
Abstract: The shear strength (V) of reinforced concrete (RC) beams consists of two parts: shear resistance of concrete (Vc) and contribution of the transverse reinforcement (Vs). Previous experimenta...
TL;DR: Precast concrete bridge substructures accelerate construction and limit residual displacements after earthquakes when used with non-emulative connections as discussed by the authors, which can also limit residual displacement after earthquakes.
Abstract: Precast concrete bridge substructures accelerate construction. Precast concrete piers can also limit residual displacements after earthquakes when used with nonemulative connections. This p...
TL;DR: In this article, an experimental study was conducted into the degree of composite action that can arise between cold-formed steel joists and wood-based flooring panels, and a series of material, push-out and 4-...
Abstract: An experimental study was conducted into the degree of composite action that can arise between cold-formed steel joists and wood-based flooring panels. A series of material, push-out and 4-...
TL;DR: In this paper, a finite element modeling approach has been used to predict the nonlinear behavior and failure patterns of rectangular reinforced concrete structural walls, and the efficiency of the model was evaluated.
Abstract: A finite-element modeling approach has been used in this study to predict the nonlinear behavior and failure patterns of rectangular reinforced concrete structural walls. Efficiency of the ...
TL;DR: In the 2010/2011 Canterbury earthquakes in New Zealand, several reinforced concrete (RC) walls in multistory buildings formed only a limited number of cracks at the wall base with a fra...
Abstract: During the 2010/2011 Canterbury earthquakes in New Zealand, several reinforced concrete (RC) walls in multistory buildings formed only a limited number of cracks at the wall base with a fra...
TL;DR: In this article, a cross-laminated timber (CLT) panel is a heavy timber structural component fabricated by laminating layers of timber boards in an orthogonal pattern.
Abstract: A cross-laminated timber (CLT) panel is a heavy timber structural component fabricated by laminating layers of timber boards in an orthogonal pattern. This paper presents a study of the lat...
TL;DR: In this paper, the experimental and analytical investigations carried out on high-strength concrete beam-column joints with Grade 700 longitudinal bars in beams and columns were carried out, and seven full...
Abstract: This study presents the experimental and analytical investigations carried out on high-strength concrete beam-column joints with Grade 700 longitudinal bars in beams and columns. Seven full...
TL;DR: In this paper, a new design form for prestressed shear walls with horizontal bottom slits utilizing cast-in-place technology is introduced, where horizontal slits are placed symmetrically at the wall-foundation interface of prestressed walls while the concrete in the middle of the wall width remains connected with the foundation.
Abstract: This paper introduces a new design form for prestressed shear walls with horizontal bottom slits utilizing cast-in-place technology. Horizontal slits are placed symmetrically at the wall-foundation interface of prestressed shear walls while the concrete in the middle of the wall width remains connected with the foundation. Furthermore, unbonded prestressed tendons inside the wall are adopted to provide self-centering ability. Tests on prestressed self-centering shear walls with horizontal bottom slits under cyclic loading were conducted to investigate their seismic performance. Test results were analyzed from the tests, and a comparison was made among traditional shear wall and self-centering shear walls with horizontal bottom slits of different configurations. The experimental results indicate that the tested cast-in-place shear walls exhibit excellent self-centering ability with the lateral load capacity similar to traditional shear walls. The quantity and distribution range of the cracking in t...
TL;DR: In this paper, a probabilistic building-specific loss estimation methodology that can explicitly account for the main sources of variability related to seismic hazards and structural response is used for this purpose.
Abstract: This paper quantifies the collapse risk and earthquake-induced economic losses of steel-frame buildings with special concentrically braced frames designed in urban California. A probabilistic building-specific loss estimation methodology that can explicitly account for the main sources of variability related to seismic hazards and structural response is used for this purpose. It is shown that, depending on the choice of the loss metric, at seismic events with low probability of occurrence (i.e., 2% probability of occurrence in 50 years), losses because of demolition and structural collapse in steel-frame buildings with special concentrically braced frames designed in highly seismic zones may be significantly overestimated when ignoring the contribution of the composite floor and gravity framing system to the analytical model building representation. For frequent and moderately frequent seismic events (i.e., 50 and 10% probability of exceedance over 50 years of building life expectancy), acceleration-sensitive nonstructural component repairs govern building losses regardless of the analytical model representation used. For the same seismic events, an appreciable contributor to total losses in steel-frame buildings with special concentrically braced frames is structural repairs because of steel brace flexural buckling. It is suggested that dual-parameter rather than drift-based steel brace fragility curves should be used in loss computations conditioned on a single seismic intensity. Otherwise, the expected annual losses should be used as a metric for building-specific loss assessment of steel-frame buildings with special concentrically braced frames.
TL;DR: In this paper, experimental and numerical investigation of cold-formed steel (CFS)-framed walls sheathed with corrugated steel sheets is presented, which is considered as an alternative shear wall configuration for midrise buildings at strong earthquake and high-wind regions.
Abstract: The paper presents experimental and numerical investigation of cold-formed steel (CFS)–framed walls sheathed with corrugated steel sheets. The new wall technology is considered as an alternative shear wall configuration for midrise buildings at strong earthquake and high-wind regions because of its attributes of noncombustibility and higher structural performance than the conventional shear wall types. However, design provisions of such corrugated sheathed CFS-framed shear walls have not been included in the current design standards. To establish comprehensive database information and to observe the performance of the bearing wall for the first time, a test program of full-scale wall assemblies using corrugated steel sheathing was conducted. The test specimens included both shear wall specimens and bearing wall specimens under lateral and vertical/gravity loading. In accordance with the full-scale tests, a numerical model was developed in a computer program, and seismic performance assessment was ...
TL;DR: Fracture is an extreme limit state in steel structures, often precipitating structural failure or serious loss of function as discussed by the authors, and methods to predict fracture in civil structures include traditional methods such as tradition...
Abstract: Fracture is an extreme limit state in steel structures, often precipitating structural failure or serious loss of function. Methods to predict fracture in civil structures include tradition...
TL;DR: In this paper, the boundary conditions of precast concrete frames play a crucial role in their progressive collapse resistance under middle column removal scenarios, and interior and exterior frames behave differ differently.
Abstract: Boundary conditions of precast concrete frames play a crucial role in their progressive collapse resistance under middle column removal scenarios. Interior and exterior frames behave differ...
TL;DR: In this paper, two full-scale, two-story, low-ductility steel concentrically braced frame (CBF) systems were tested to evaluate failure mechanisms, postelastic frame behavior, reserve capacity, and overal capacity.
Abstract: Two full-scale, two-story, low-ductility steel concentrically braced frame (CBF) systems were tested to evaluate failure mechanisms, postelastic frame behavior, reserve capacity, and overal...
TL;DR: In this article, a simple and reliable homogenization approach coupled with rigid elements and homogenized interfaces for the analysis of out-of-plane loaded masonry panels is presented.
Abstract: This paper presents a simple and reliable homogenization approach coupled with rigid elements and homogenized interfaces for the analysis of out-of-plane loaded masonry panels. The homogeni...
TL;DR: In this article, the authors presented the seismic upgrade of existing frame structures by using the self-centering (SC) concrete wall with friction dampers working principle, numerical simulation, and desig
Abstract: This paper presents the seismic upgrade of existing frame structures by using the self-centering (SC) concrete wall with friction dampers Working principle, numerical simulation, and desig
TL;DR: In this article, the experimental results of dynamically removing an interior column in a single-story, 2-bay-by-2-bay reinforced concrete flat-plate substructure were presented.
Abstract: The experimental results of dynamically removing an interior column in a single-story, 2-bay-by-2-bay reinforced concrete flat-plate substructure are presented. The test specimen represente...
TL;DR: In this paper, a new construction technique was proposed to improve the seismic performance of infilled RC frames by increasing the strength and stiffness of the infill and/or the frame.
Abstract: A number of construction techniques have been proposed to improve the seismic performance of infilled RC frames by increasing the strength and stiffness of the infill and/or the frame. The increase of the seismic capacity of infilled frames with these techniques can improve substantially their seismic performance as long as the demand does not exceed the capacity, but it can eventually lead to brittle failures once the capacity is exceeded. This study assesses numerically a new construction technique that introduces flexibility to the system to ensure its ductile behavior and minimal damage by splitting the infill in subportions and allowing the sliding along the horizontal joints connecting these subportions. A numerical model, validated with data from tests on the components of the proposed structural system and able to capture the interaction between them, has been developed to provide insight into the load-transfer mechanism that develops, and to optimize the proposed detailing. A parametric s...
TL;DR: In this article, wind-induced vibrations of the Hardanger Bridge deck were studied with reference to turbulence characteristics at the bridge site to evaluate the performance of the state-of-the-art methods.
Abstract: Wind-induced vibrations of the Hardanger Bridge deck were studied with reference to turbulence characteristics at the bridge site to evaluate the performance of the state-of-the-art methods...