Parametric Analysis of the Shear Lag Effect in Tube Structural Systems of Tall Buildings

Horizontal loads such as earthquake and wind are considered dominant loads for the design of tall buildings. One of the most efficient structural systems in this regard is the tube structural system. Even though such systems have a high resistance when it comes to horizontal loads, the shear lag effect that is characterized by an incomplete and uneven activation of vertical elements may cause a series of problems such as the deformation of internal panels and secondary structural elements, which cumulatively grow with the height of the building. In this paper, the shear lag effect in a typical tube structure will be observed and analyzed on a series of different numerical models. A parametric analysis will be conducted with a great number of variations in the structural elements and building layout, for the purpose of giving recommendations for an optimal design of a tube structural system.

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Shear-lag effect and its effect on the design of high-rise buildings

E3S Web of Conferences ◽

10.1051/e3sconf/20183302001 ◽

2018 ◽

Vol 33 ◽

pp. 02001 ◽

Cited By ~ 1

Author(s):

Bui Thanh Dat ◽

Alexander Traykov ◽

Marina Traykova

Keyword(s):

Major Part ◽

Tall Buildings ◽

Lateral Load ◽

Structural Systems ◽

Lateral Loads ◽

Shear Lag ◽

Shear Lag Effect ◽

Main Category ◽

High Rise ◽

Lag Effect

For super high-rise buildings, the analysis and selection of suitable structural solutions are very important. The structure has not only to carry the gravity loads (self-weight, live load, etc.), but also to resist lateral loads (wind and earthquake loads). As the buildings become taller, the demand on different structural systems dramatically increases. The article considers the division of the structural systems of tall buildings into two main categories - interior structures for which the major part of the lateral load resisting system is located within the interior of the building, and exterior structures for which the major part of the lateral load resisting system is located at the building perimeter. The basic types of each of the main structural categories are described. In particular, the framed tube structures, which belong to the second main category of exterior structures, seem to be very efficient. That type of structure system allows tall buildings resist the lateral loads. However, those tube systems are affected by shear lag effect - a nonlinear distribution of stresses across the sides of the section, which is commonly found in box girders under lateral loads. Based on a numerical example, some general conclusions for the influence of the shear-lag effect on frequencies, periods, distribution and variation of the magnitude of the internal forces in the structure are presented.

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Study of shear lag effect in a hybrid structural system for high-rise buildings

Technology Drivers: Engine for Growth ◽

10.1201/9780203713143-23 ◽

2018 ◽

pp. 153-158

Author(s):

Deep Modi ◽

Paresh V. Patel ◽

Digesh Joshi

Keyword(s):

Structural System ◽

Shear Lag ◽

Shear Lag Effect ◽

High Rise ◽

Lag Effect

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Shear Lag Effect In The Numerical Experiment

Archives of Civil Engineering ◽

10.1515/ace-2015-0023 ◽

2015 ◽

Vol 61 (3) ◽

pp. 31-50 ◽

Cited By ~ 1

Author(s):

M. Szumigała ◽

K. Ciesielczyk

Keyword(s):

3D Model ◽

Beam Theory ◽

Structural Elements ◽

Shear Lag ◽

Shear Lag Effect ◽

Lag Effects ◽

Plate Buckling ◽

Lag Effect ◽

Comparison Of The Results ◽

Elastic Shear

AbstractThe standard PN-EN 1993-1-5: 2008 (Eurocode 3) compared with the standard (PN-B-03200: 1990) used previously in Poland, introduces extended rules referring to the computations of the bearing capacity of the plated structural elements including the shear lag effect. The stress distribution in the width flanges is variable. Therefore in the case of the beam with the shear lag effect cannot be calculated by the classic beam theory.In this article a comparison of the results of the calculations of forces distribution, stresses and displacement according to the rule presented in PN-EN 1993 and results of the numerical computations for 3D model (using finite element method) is presented. The elastic shear lag effects, the elastic shear lag effects including effects of the plate buckling and the elastic-plastic shear lag effects including the local instabilities were analysed. The calculations were performed for beams with a small and a large span and an influence of stiffeners was analysed.

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Influence of Shear Lag and Shear Deformation Effects on Deflection of Composite Box Girder with Corrugated Steel Webs

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.671-674.985 ◽

2013 ◽

Vol 671-674 ◽

pp. 985-990 ◽

Cited By ~ 2

Author(s):

Peng Qiao

Keyword(s):

Shear Deformation ◽

Parametric Analysis ◽

Shear Lag ◽

Shear Lag Effect ◽

Deformation Effect ◽

Box Girder ◽

Composite Girder ◽

Deflection Coefficient ◽

Lag Effect ◽

Span Width

The shear lag and shear deformation effects on deflection of composite girder with corrugated steel webs (CGCSW) was studied. The influence of shear lag and shear deformation effect was expressed by deflection coefficient δ1 and δ2. Parametric analysis within a scope of dimensions of built-in girders was performed, including girder span, width, height, thickness of concrete flange and thickness of steel web. The results show that the deflection coefficient of shear lag effect is approximately directly proportional to square of width-span ratio, while the deflection coefficient of shear deformation effect is related to all parameters. It’s suggested that shear lag effect on CGCSW’s deflection be neglected when width-span ratio is smaller than 1/9, and shear deformation effect should always be considered.

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Lateral Displacement and Shear Lag Effect of Combination of Diagrid-Frame

E3S Web of Conferences ◽

10.1051/e3sconf/20183401009 ◽

2018 ◽

Vol 34 ◽

pp. 01009 ◽

Cited By ~ 1

Author(s):

Roslida Abd. Samat ◽

Fong Teng Chua ◽

Nur Akmal Hayati Mohd Mustakim ◽

Sariffuddin Saad ◽

Suhaimi Abu Bakar

Keyword(s):

Lateral Displacement ◽

Tall Buildings ◽

Ground Level ◽

Lateral Load ◽

Tall Building ◽

Shear Lag ◽

Shear Lag Effect ◽

Lag Effect ◽

Level 1 ◽

Diagrid Structure

Diagrid system, which is the portmanteau of diagonal grid member, is an exterior lateral load resisting system for tall building that has gained a wide acceptance in the design of tall buildings. There is abundance of researches that studied the efficiency of diagrid systems, which are constructed from the ground level to the top of the buildings in resisting the lateral load. Nevertheless, no study had been performed on the effectiveness of the diagrid that is constructed above other tall building systems despite the existence of a few buildings in the world that employ such system. The objective of this research is to understand the behavior of the lateral displacement and shear lag effect due to wind load when the diagrid structure is constructed above a frame. Models of 60-story buildings with a footprint of 36m x 36m were analyzed by using Staad.Pro software. The level where the diagrid members started was altered. The lateral displacement was reduced to 60.6 percent and 41 percent of the lateral displacement of a building with full frame system when the combination of frame-diagrid that had the diagrid started at Level 1 and Level 45, respectively were employed. Furthermore, the shear lag ratio was reduced from 1.7 to 1.3 when the level where the diagrid started was increased from Level 1 to Level 45.

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