• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.12
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• pp.5931-5937
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• 2011

The effects of coupling beam, which is generally used in high-rise building structure system as shear wall-coupling beam, on the lateral drift of high-rise buildings are studied in this paper. Six different analytical models, which are combination of two inputs, such as concrete strength and wall thickness, are selected and analyzed on lateral drifts with different stiffness of coupling beams. MIDAS GEN was used for analysis. Calculated lateral drifts were compared with allowable limits(H/400~H/500) proposed by standard CEN EC 3/1, in order to analyze the control evaluation of coupling beams. Calculated x-direction displacements were 68~87 percent of allowable limit(H/500). With increase of wall thickness(100mm) and concrete strength(5Mpa), eight to ten percent and four percent of x and y-direction displacement were decreased individually. About three percent of lateral displacement was increased with 20 percent decrease of coupling beam stiffness and additional 20 percent decrease resulted in additional five to eight percent increase.

• Geotechnical Engineering
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• v.13 no.4
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• pp.55-66
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• 1997

In order to investigate the influence of installation angle of reticulated root piles(RRP) on their lateral load capacities, model tests of lateral loads on RRP with various installation angles $0^{\circ}\;, 5^{\circ}\;, 10^{\circ}\;, 15^{\circ}\;, 20^{\circ}\;,and 25^{\circ}$ are carried out. One set of RRP consists of 12 piles which are installed in circular patterns forming two concentric circles, each of which has 6 piles. Each pile made of a steel bar of 5mm in diameter and 350mm in length, is coated with sand until the bar has the diameter of 6.5mm. According to the test results, RRP's response is travily influenced by the displacement level. At low displacement level(1m), lateral load capacity increases as the installation angle is increased. However, the value of the optimum installation angle decreases as the displacement level is increased. In fact, it is found to be $17.5^{\circ}$ at 6mm lateral displacement. The ratios of the lateral resistances for the optimum installation angles to those for the vertical RRP decrease as the lateral displacements are increased. Thus the effect of slant ins angle of RRP is expected to be reduced at higher level of lateral displacement.

• Journal of the Korean GEO-environmental Society
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• v.21 no.5
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• pp.13-21
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• 2020

In this study, the reliability of the lateral spring constant (k1) applied during design of pile foundation for bridge abutment was evaluated. To do this, the reliability of the factors related to the prediction of the lateral displacement of the abutment pile foundation, which was designed based on the displacement method proposed by Chang (1937), was analyzed. The data used for analysis were the design statements of ◯◯ bridge and ◯◯ IC2 bridge. Then, it was derived by comparing with the numerical analysis (p-y analysis) based on the basic data.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.5
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• pp.42-49
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• 2009

The effects of various forces acting on concrete pole are analyzed using finite element method how the forces affect on ground displacement. The soil types, wind load location of anchor block embedded depth of pole, and distance between poles are varied to find out effects on lateral displacement. Anchor block is effective when it is located at 1/4 of embedded depth The displacement is decreases as elastic modulus increases. Concrete reinforcement for loosened ground is necessary for double poles because double poles cause large excavation. When embedded depth ratio decrease, lateral displacement increase as closer to ground surface. Large embedded depth is effective to reduce lateral displacement, and the distance between poles is not much large factor.

• Journal of the Korean Geotechnical Society
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• v.33 no.2
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• pp.17-26
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• 2017

Pile foundations that support offshore structures or transmission towers are dominantly subjected to cyclic lateral loads due to wind and waves, causing permanent displacement which can severely affect stability of the structures. In this study, a series of cyclic lateral load tests were conducted on a pre-installed aluminum flexible pile in sandy soil with three different relative densities (40%, 70% and 90%) in order to evaluate the permanent displacement of a cyclic laterally loaded pile. Test results showed that the cyclic lateral loads accumulated the irreversible lateral displacement, so-called permanent displacement. As the number of cyclic lateral load increased, accumulated permanent displacement increased, but the permanent displacement due to one loading cycle gradually decreased. In addition, the permanent displacement of a pile increased with decrement of relative density and decreased by soil saturation. From the test results, the normalized permanent displacement defined as the cumulative permanent displacement to the initial permanent displacement ratio was investigated, and empirical equations for predicting the normalized permanent displacement was developed in terms of relative density of the soil and the number of cyclic lateral load.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.25 no.6
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• pp.505-512
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• 2012

In this paper, an efficient yet accurate method for the thermal stress analysis using a first order shear deformation theory(FSDT) is presented. The main objective herein is to systematically modify transverse shear strain energy through the mixed variational theorem(MVT). In the mixed formulation, independent transverse shear stresses are taken from the efficient higher-order zigzag plate theory, and the in-plane displacements are assumed to be those of the FSDT. Moreover, a smooth parabolic distribution through the thickness is assumed in the transverse normal displacement field in order to consider a transverse normal deformation. The resulting strain energy expression is referred to as an enhanced first order shear deformation theory, which is obtained via the mixed variational theorem with transverse normal deformation effect(EFSDTM_TN). The EFSDTM_TN has the same computational advantage as the FSDT_TN(FSDT with transverse normal deformation effect) does, which allows us to improve the through-the-thickness distributions of displacements and stresses via the recovery procedure. The thermal stresses obtained by the present theory are compared with those of the FSDT_TN and three-dimensional elasticity.

• 건설안전세미나
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• s.1
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• pp.75-114
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• 1990

• Journal of the Earthquake Engineering Society of Korea
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• v.9 no.3 s.43
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• pp.69-75
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• 2005

In this paper, the comparative performance of repaired RC columns using steel and CFRP is presented. Also, the effect of transverse reinforcement ratio on the behavior of the steel and the CFRP repairing is investigated. Monotonic and cyclic load tests are conducted on nine RC column specimens with different repairing strategies and transverse reinforcement ratios to compare the load-displacement curves and the hysteretic behaviors. From the tests, it is observed that both steel and CFRP jacket repairings can significantly increase the displacement ductility and the ultimate load capacity of damaged columns.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.6
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• pp.267-274
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• 2021

Among several methods for determining the allowable lateral resistances of piles, the subgrade reaction method and ultimate lateral resistance method are generally used. To determine the effects of the soil conditions, pile head restraint conditions, and pile lengths on determining the allowable lateral resistances of piles, computations of the allowable lateral resistances of piles using the two methods were executed, and the computation results were compared. For piles in soft cohesive soil, the pile design is governed by the allowable lateral resistance of a pile from subgrade soil reaction method regardless of the pile head restraints conditions and pile lengths. The allowable lateral resistance of a pile from the ultimate lateral resistance governs the design as the undrained shear strength increases. Except for the case of a short pile, which is installed in loose granular soil, the allowable lateral resistance of a pile from ultimate lateral resistance governs the design of laterally loaded piles. According to this study, computation of the ultimate lateral resistance of a pile is needed, even though some opinions suggest that the design of a laterally loaded pile is satisfied only by the subgrade reaction method. The pile width barely influences the coefficient of horizontal subgrade reaction. Realistically, the effect of the pile width can be disregarded in the condition of common pile widths of 20~90cm.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.3
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• pp.249-257
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• 2011

In this paper, an systematic approach is presented, in which the mixed variational theorem is employed to incorporate independent transverse shear stresses into a classical higher-order shear deformation theory(HSDT). The HSDT displacement field is taken to amplify the benefits of using a classical shear deformation theory such as simple and straightforward calculation and numerical efficiency. Those independent transverse shear stresses are taken from the fifth-order polynomial-based zig-zag theory where the fourth-order transverse shear strains can be obtained. The classical displacement field and independent transverse shear stresses are systematically blended via the mixed variational theorem. Resulting strain energy expressions are named as an enhanced higher-order shear deformation theory via mixed variational theorem(EHSDTM). The EHSDTM possess the same computational advantage as the classical HSDT while allowing for improved through-the-thickness stress and displacement variations via the post-processing procedure. Displacement and stress distributions obtained herein are compared to those of the classical HSDT, three-dimensional elasticity, and available data in literature.