• Journal of Korean Society of Steel Construction
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• v.21 no.3
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• pp.233-243
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• 2009

The objective of this study was to investigate the effect of openings on the structural behavior of SC walls. The FEM program ABAQUS was used in this analytical study. The main parameters were the locations and sizes of the openings: a total of 20 locations and a total of four opening sizes were adopted. The analysis results were compared with the results of the currently applied evaluation methods. The strength reduction factor method may be used to safely design SC walls with openings. The strength reduction factor of the effective strut method is more similar to that of the analysis results.

• Journal of the Korea institute for structural maintenance and inspection
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• v.13 no.6 s.58
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• pp.183-191
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• 2009

In this study, the behavior and safety factor of a nailed-soil excavation wall during earthquake is presented. The horizontal displacement, axial force, shear force, and moment of facing of a nailed-soil excavation wall subjected to static and seismic load are analyzed using time history analysis. The safety factor based on the strength reduction technique proposed by Dawson and Roth is used to calculate the safety factor of a nailed-soil excavation wall during earthquake. The safety factor by the proposed method is verified by comparing with those by other methods.

• 건축구조
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• v.11 no.2
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• pp.45-48
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• 2004

• 건축구조
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• v.8 no.3
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• pp.40-41
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• 2001

• Journal of the Korea institute for structural maintenance and inspection
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• v.12 no.2
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• pp.59-66
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• 2008

In the construction site, to improve the man-dependent form work, non-stripping form has been studied but the developed non-stripping form was hard to applied with respect to the cost, form size and performance. This study is for evaluating the adaptability of the developed non-stripping form named as high performance permanent form (HPPF). To do this, the analytical approach and parametric study were performed based on the research for fundamental material characteristic of the HPPF. The target concrete structure is a wall structure because of its effectiveness of HPPF. To evaluate the structural efficiency of the HPPF applied wall structure, FEM analysis was performed to decide the maximum placing height at one time then it was applied to design the wall structure. In the result of the analysis, the HPPF applied wall structure showed the lots of advantages that it can reduce the cost resulted from reducing concrete and steel rebar even if it has same structural performance to the conventional concrete wall structure with same dimension. With this analysis result, it can be evaluated that the HPPF applied concrete structure can be a concrete structure with the long term durability in site.

• Journal of the Korean Wood Science and Technology
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• v.37 no.4
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• pp.320-329
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• 2009

The purpose of this study was reducing the moisture accumulation in a wall, which can threaten the structural safety of light-frame wall and make residential environment poor. For the purpose, the laboratory test was carried out with different wall assemblies. Vapor retarder and air gap for ventilation were added to the typical wall. The improved performance of the proposed walls was examined through the test with distinct difference of temperature and relative humidity between outdoor and indoor air conditions. Increased dampproofing performance of additional vapor retarder was effective on reduction of moisture transmission from inside the house into the wall. However, unexpected high relative humidity was shown in the wall with two additional vapor retarder because of excessive dampproofing performance or inadequate location of vapor retarder. And, the open air gap induced the moisture transfer from inside the wall into outdoor air by ventilation. If the alternative to the induction of moisture transmission from inside the house into the wall with open air gap can be found, moisture reduction effect of that will be increased obviously.

• Journal of the Korean Society for Advanced Composite Structures
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• v.1 no.3
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• pp.41-48
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• 2010

In this paper, the analysis of impact damage behavior of a reinforced concrete structure that undergoes both a shock impulsive loading and an impact loading due to the air blast induced from an explosion is performed. Firstly, a pair of multiple loadings are selected from the scenario that an imaginary explosion accident is assumed. The RC structures strengthened with advanced composite materials (ACM) are considered as a scheme for retrofitting RC wall structures subjected to multiple explosive loadings and then the evaluation of the resistant performance against them is presented in comparison with the result of the evaluation of a RC structure without a retrofit. Also, in order to derive the result of the analysis similar to that of real explosion experiments, which require the vast investment and expense for facilities, the constitutive equation and the equation of state (EOS) which can describe the real impact and shock phenomena accurately are included with them. In addition, the numerical simulations of two concrete structures are achieved using AUTODYN-3D, an explicit analysis program, in order to prove the retrofit performance of a ACM-strengthened RC wall structure.

• Journal of the Korea institute for structural maintenance and inspection
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• v.17 no.3
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• pp.28-39
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• 2013

The most common housing type in Korea is low-rise buildings with unreinforced masonry walls (UMWs) that have been known as a vulnerable seismic-force-resisting system (SFRS) due to the lack of ductility capacities compared to high lateral stiffness of an UMW. However, there are still a little experimental investigation on the shear strength and stiffness of UMWs and on the seismic performance of buildings using UMWs as a SFRS. In Korea, the shear strength and stiffness of UMWs have been evaluated with the equations suggested in FEMA 356 which can not reflect the structural and material characteristics, and workmanship of domestic UMW construction. First of all, this study demonstrates the differences in shear strength and stiffness of UMWs obtained from between FEMA 356 and test results. The influence of these differences on the seismic performance of UMW buildings is then discussed with incremental dynamic analyses results of a prototype UMW building that were selected by the site survey of more than 200 UMW buildings and existing test results of UMWs. The seismic performance assessment of the prototype UMW building are analyzed based on collapse margin ratios and beta values repesenting uncertainty of seismic capacity. Analysis results show that the seismic performance of the UMW building estimated using the equations in FEMA 356 underestimates both a collapse margin ratio and a beta value compared to that estimated by test results. Whatever the estimation is carried out two cases, the seismic performance of the prototype building does not meet the criteria prescribed in a current Korean seismic code and about 90% collapse probability presents for more than 30-year-old UMW buildings under earthquakes with 2400 return years.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1999.06a
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• pp.157-162
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• 1999

본 연구는 현장의 굴착공사에 따른 토류 구조물 설치공사의 수행에 있어서 토류 벽체의 지지 구조체률 형성하는 Earth Anchor에 대한 시공의 적정성 여부 및 설계목적에의 부합 여부를 판정하여 토류 벽체의 안정성 판단 및 Earth Anchor의 설계 목적에의 부합성 여부를 판단하기 위하여 본 연구를 수행하며 실험의 기준은 SIA. Standard Edition 1977 규정에 따르며, Earth Anchor의 설계, 정착장 및 자유장의 길이를 적절히 산출하고 정착력에 대한 신뢰도, 즉 인발력을 실험하여 정착장의 소요 안전율을 추정하며 더불어 지반에 대한 비교, 판단도 행하는 것이 목적이다. (중략)

• Journal of the Computational Structural Engineering Institute of Korea
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• v.35 no.1
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• pp.57-64
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• 2022

This study investigated the structural performance of the RC boundary beam-wall system subjected to axial loads that required lesser construction quantity and smaller floor height in comparison with the conventional RC transfer girder system. Four specimens of 1/2 scale were constructed, and their peak strengths under axial loads and failure characteristics were compared and analyzed. Test parameters included the ratio of the lower to the upper wall length, lower wall thickness, and stirrup details of the lower wall. In addition, three-dimensional nonlinear finite element analysis was performed to verify the effectiveness of the boundary beam-wall system. The peak strength of each specimen was similar to the nominal axial strength of the lower wall, indicating that the axial load was transferred smoothly from the upper to the lower wall. The contribution of the lower wall cross-section was high if the ratio of the lower to the upper wall length was small; the contribution was low if the out-of-plane eccentricity existed in the lower wall. The specimen with smaller stirrup distance and cross-ties in the lower wall showed higher initial stiffness and peak load than other specimens.