Spatial stability of pre-stressed mono-symmetric steel beams with un-bonded/bonded deviators under compression and end moments

This paper studies the shear performance of the connection with the external stiffening ring between the square steel tubular column and unequal-depth steel beams. Two specimens of interior column connections were tested under low cyclic loading. The deformation characteristics and failure modes exhibited by the test phenomena can be summarized as: (1) two specimens all exhibited shear deformation in steel tube web of the panel zone and (2) weld fracture in the panel zone and plastic hinge failure at beam end were observed. Besides, load-displacement behaviors and strain distributions have been also discussed. The nonlinear finite element models were developed to verify the test results. Comparative analyses of the bearing capacity, failure mode, and load-paths between the equal-depth and unequal-depth beam models have been carried out.

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Hate Crime and Place: The Spatial and Temporal Concentration of Bias-Motivated Crime in Washington, D.C.

Journal of Interpersonal Violence ◽

10.1177/0886260520987817 ◽

2021 ◽

pp. 088626052098781

Author(s):

Marin R. Wenger ◽

Brendan Lantz

Keyword(s):

Hate Crime ◽

Hate Crimes ◽

Temporal Perspective ◽

Spatial Stability ◽

Units Of Analysis ◽

Crime Types ◽

High Degree ◽

Block Groups ◽

Street Segments

Prior research suggests that many crime types are spatially concentrated and stable over time. Hate crime, however, is a unique crime type that is etiologically distinct from others. As such, examination of hate crime from a spatial and temporal perspective offers an opportunity to understand hate crime and the spatial concentration of crime more generally. The current study examines the spatial stability of hate crimes reported to the police in Washington, D.C., from 2012 through 2018 using street segments, intersections, and block groups as units of analysis. Findings reveal that hate crime is spatially concentrated, with less than 4% of street segments and intersections experiencing hate crime over the study period. Results reveal a high degree of spatial stability, both year-to-year and over the long term even when restricting the analysis to units that experienced at least one hate crime.

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Study on the Flexural Fatigue Performance of CFRP-OFBG Plate Reinforced Damaged Steel Beams

KSCE Journal of Civil Engineering ◽

10.1007/s12205-021-1138-y ◽

2021 ◽

Author(s):

Langni Deng ◽

Mengjun Zhong ◽

Yang Liu ◽

Ling Liao ◽

Shijin Lai ◽

...

Keyword(s):

Fatigue Performance ◽

Steel Beams ◽

Flexural Fatigue

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Experimental analysis on cold-formed steel beams subjected to fire

Thin-Walled Structures ◽

10.1016/j.tws.2013.09.006 ◽

2014 ◽

Vol 74 ◽

pp. 104-117 ◽

Cited By ~ 17

Author(s):

Luís Laím ◽

João Paulo C. Rodrigues ◽

Luis Simões da Silva

Keyword(s):

Experimental Analysis ◽

Steel Beams ◽

Cold Formed Steel

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Development of Optimal Design Method for Steel Double-Beam Floor System Considering Rotational Constraints

Applied Sciences ◽

10.3390/app11073266 ◽

2021 ◽

Vol 11 (7) ◽

pp. 3266

Author(s):

Insub Choi ◽

Dongwon Kim ◽

Junhee Kim

Keyword(s):

Optimal Design ◽

Design Process ◽

Design Method ◽

Steel Beams ◽

High Gravity ◽

Double Beam ◽

Iterative Analysis ◽

Floor Systems ◽

Optimal Design Method ◽

Floor System

Under high gravity loads, steel double-beam floor systems need to be reinforced by beam-end concrete panels to reduce the material quantity since rotational constraints from the concrete panel can decrease the moment demand by inducing a negative moment at the ends of the beams. However, the optimal design process for the material quantity of steel beams requires a time-consuming iterative analysis for the entire floor system while especially keeping in consideration the rotational constraints in composite connections between the concrete panel and steel beams. This study aimed to develop an optimal design method with the LM (Length-Moment) index for the steel double-beam floor system to minimize material quantity without the iterative design process. The LM index is an indicator that can select a minimum cross-section of the steel beams in consideration of the flexural strength by lateral-torsional buckling. To verify the proposed design method, the material quantities between the proposed and code-based design methods were compared at various gravity loads. The proposed design method successfully optimized the material quantity of the steel double-beam floor systems without the iterative analysis by simply choosing the LM index of the steel beams that can minimize objective function while satisfying the safety-related constraint conditions. In particular, under the high gravity loads, the proposed design method was superb at providing a quantity-optimized design option. Thus, the proposed optimal design method can be an alternative for designing the steel double-beam floor system.

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Flexural strengthening of steel beams using pultruded CFRP composite sheets with anchorage mechanisms

Structures ◽

10.1016/j.istruc.2021.05.024 ◽

2021 ◽

Vol 33 ◽

pp. 1414-1427

Author(s):

Selvakumarasami Kumaraguru ◽

Paramasivan Alagusundaramoorthy

Keyword(s):

Steel Beams ◽

Flexural Strengthening ◽

Cfrp Composite

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