• Proceedings of the Computational Structural Engineering Institute Conference
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• 2001.04a
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• pp.343-350
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• 2001

The box system, composed only of reinforced concrete walls and slabs, are adopted by many high-rise apartment buildings recently constructed in Korea. In the buildings, one or more relatively large openings are cut in a shear wall for functional reasons. The openings influence the internal stress of the shear wall and also the structural behavior. Therefore, it is necessary to use subdivided plate elements for accurate analysis of the box system with openings. But it would cost tremendous amount of analysis time and computer memory if the shear wall is subdivided into a finer mesh in the analysis of high-rise buildings. So, it is difficult to apply this modeling method to practical procedure. In this study, an efficient method is proposed for the efficient and accurate analysis of shear wall with openings. The proposed method used the super element and matrix condensations, fictitious beam technique.

• Architectural research
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• v.24 no.3
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• pp.75-84
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• 2022

Scads of earthquake-resistant systems are being invented around the globe to ensure structural resistance against the lateral forces induced by earthquake loadings considering structural safety, efficiency, and economic aspects. Shear wall and Bracing systems are proved to be two of the most viable solutions for seismic strengthening of structures. In the present study, three numerical models of a G+10 storied building are developed in commercial building analysis software considering shear wall and bracing systems for earthquake resistance. Material nonlinearity is introduced by using plastic hinges. Analyses are performed utilizing two dynamic methods: Response Spectrum analysis and nonlinear Time-history analysis using Kobe and Loma Prieta earthquake data and results are compared to observe the nonlinear behavior of structures. The outcomes exposed that a significant increase in the seismic responses occurs due to the nonlinearity in the building systems. It was also found that building with shear wall exhibits maximum resistance and minimum nonlinearity when subjected to dynamic loadings.

• Geomechanics and Engineering
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• v.12 no.6
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• pp.1021-1046
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• 2017

The assessment of slope stability is an essential task in geotechnical engineering. In this paper, a three-dimensional (3D) finite element analysis (FEA) was employed to investigate the performance of different shear pin arrangements to increase the stability of a soil block resting on an inclined plane with a low-interface friction plane. In the numerical models, the soil block was modeled by volume elements with linear elastic perfectly plastic material in a drained condition, while the shear pins were modeled by volume elements with linear elastic material. Interface elements were used along the bedding plane (bedding interface element) and around the shear pins (shear pin interface element) to simulate the soil-structure interaction. Bedding interface elements were used to capture the shear sliding of the soil on the low-interface friction plane while shear pin interface elements were used to model the shear bonding of the soil around the pins. A failure analysis was performed by means of the gravity loading method. The results of the 3D FEA with the numerical models were compared to those with the physical models for all cases. The effects of the number of shear pins, the shear pin locations, the different shear pin arrangements, the thickness and the width of the soil block and the associated failure mechanisms were discussed.

• Journal of the Korean Geotechnical Society
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• v.16 no.6
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• pp.35-41
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• 2000

Residual stress is defined as a minimum stress with a large displacement of specimens and the residual stress after peak shear stress appears with displacement volume but there is no provision to select the residual stress. In the previous study, residual stress was recorded when the change of shear load is small in the condition of the strain more than 15%. But, in this study, hyperbolic function((No Abstract.see full/text), b=experimental constant) of soil test is adapted to joint of rock and the propriety is investigated. In a landslide and landsliding of artificial slope, wedge failure of tunnel with a large displacement, tests are simulated from peak stress to residual stress for safety analysis. But now. direct shear stress and triaxial compressive tests are usually performed to find out characteristics of shear stress about joint. Although these tests get a small displacement, that data of peak stress and residual stress are used for safety analysis. In this study, we tried to determine failure criteria for joints of rock using ring shear test machine. The residual stress following shear behavior was determined by the result of ring shear test and direct shear test. In conclusion, after comparing the results of the two test, we found that cohesion(c) and internal friction angle(ø) of ring shear test are 30% and 22% respectively of those of the direct shear test.

• Journal of the Korea institute for structural maintenance and inspection
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• v.26 no.2
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• pp.51-58
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• 2022

Flat plate slab is cost-efficient structural system widely used in high rise building, apartment and parking garages. But flat plate-column connections are so weak against punching shear failure that it may cause collapse of overall structure. In this study, spiral type shear reinforcement which increases the shear strength and ductility of the plate-column connection and has good workability was proposed. And experimental test was performed to verify the punching shear capacity of spiral type shear reinforcement. The current code does not accurately estimate the punching shear strength of slab-column connection with shear reinforcement because slab is so slender that punching failure may occurred before shear reinforcement reached yield stress. Therefore modified equation of ACI code for punching shear strength was proposed base on finite element analysis using LUSAS program, and data analysis from CEB-FIP database.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.48-51
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• 2004

This paper is to study the response of flat plate slab-column connections consisting of various types of shear reinforcement and steel plate subjected to gravity loadings, mainly punching shear forces using the non-destructive testing, spectral analysis of surface waves and structural experiments. The base specimen failed due to punching shear generated from the gravity. The three other types of slab shear reinforcement and steel plate showed effective in resisting punching shear for these types of connections under gravity loading. This study has focused in evaluating the velocity response of a Surface wave during the early age as the poured concrete specimens have been hardened, the possibility of damage detection in the slab-column connection and the relationship between the punching shear forces and the surface wave velocities under the condition that the punching shear forces had gradually increased until the flat plate slab in slab-column connection had been failed.

• Structural Engineering and Mechanics
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• v.18 no.1
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• pp.79-90
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• 2004

A high precision shear deformable triangular element has been proposed for bending analysis of triangular plate. The element has twelve nodes at the three sides and four nodes inside the element. Initially the element has thirty-five degrees of freedom, which has been reduced to thirty by eliminating the degrees of freedom of the internal nodes through static condensation. Plates having different boundary conditions, side ratios (b/a) and thickness ratios (h/a = 0.001, 0.1 and 0.2) have been analyzed using the proposed shear locking free element. Concentrated and uniformly distributed transverse loads have been used for the analysis. The formulation is made based on first order shear deformation theory. For validation of the present element and formulation few results of thin triangular plate have been compared with the analytical solutions. Results for thick plate have been presented as new results.

• Proceedings of the Korean Society For Composite Materials Conference
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• 1999.11a
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• pp.215-218
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• 1999

A general structural model, which is an extension of the Vlassov theory, is developed for the analysis of composite rotor blades with elastic couplings. A comprehensive analysis applicable to both thick-and thin-walled composite beams, which can have either open- or closed profile is formulated. The theory accounts for the effects of elastic couplings, shell wall thickness, and transverse shear deformations. A semi-complementary energy functional is used to account for the shear stress distribution in the shell wall. The bending and torsion related warpings and the shear correction factors are obtained in closed form as part of the analysis. The resulting first order shear deformation theory describes the beam kinematics in terms of the axial, flap and lag bending, flap and lag shear, torsion and torsion-warping deformations. The theory is validated against experimental results for various cross-section beams with elastic couplings.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.680-685
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• 2001

In this paper, RKPM is extended for solving moderately thick and thin structures. General Timoshenko beam and Mindlin plate theory are used far formulation. Shear locking is the main difficulty in analysis of these kinds of structures. Shear relaxation factor, which is formulated using the difference between bending and shear strain energy, is introduced to overcome shear locking. Analysis results obtained reveal that RKPM using introduced method is free of locking and very effectively applicable to deeply as well as shallowly beams and plates.

• Journal of the Earthquake Engineering Society of Korea
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• v.23 no.3
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• pp.169-181
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• 2019

Seismic performance of ordinary reinforced concrete shear wall systems commonly used in high-rise residential buildings is evaluated. Three types of shear walls exceeding 60m in height are designed by performance-based seismic design. Then, incremental dynamic analysis is performed collapse probability is assessed in accordance with the procedure of FEMA P695. As a result, story drift, plastic rotation, and compressive strain are observed to be major failure modes, but shear failure occur little. Collapse probability and collapse margin ratio of performance groups do not meet requirement of FEMA P695. It is observed that critical wall elements fail due to excessive compressive strain. Therefore, the compressive strain of concrete at the boundary area of the shear wall needs to be evaluated with more conservative acceptance criteria.