• Journal of Korean Society of Steel Construction
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• v.15 no.1
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• pp.17-24
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• 2003

This study aimed to develop experiment-based limiting heights for interior, nonload-bearing, cold-formed steelwall panels sheathed with gypsum board and subjected to uniformly distributed lateral loadings. Th e limiting heightswere evaluated by their strength (for flexure, shear, and web crippling) and deflection. Limiting heights for deflectionlimits of L/360, L/240, and L/120 (where L is the height of the wall) were developed over the range of typical designpressures.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.1
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• pp.56-63
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• 2018

The present study examined the reversal cyclic flexural behavior of walls with jacket section approach for seismic strengthening through forming the boundary elements at both ends of the wall. The prestressed wire ropes were used for the lateral reinforcement to confine the boundary element of the wall. The main parameter investigated was the height of the jacket section for strengthening. The limit height of the strengthening jacket section was determined by comparing the moment distributions between the existing and strengthened walls. Test results showed that the examined jacket section approach was significantly effective in enhancing the flexural resistance of walls, indicating 46% higher stiffness at peak strength and 210% greater work damage indicator, compared with the flexural performance of the unstrengthened wall. The ductility of the strengthened walls was insignificantly affected by the height of the jacket section when the height is greater than twice the wall length. The flexural capacity of the strengthened walls was 22% higher than the predictions obtained using the equivalent stress block specified in ACI 318-14.

• Journal of Korean Association for Spatial Structures
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• v.6 no.2 s.20
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• pp.93-105
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• 2006

In order to investigate the effect of the height of application point of lateral loads and reinforcing steel bars in walls and columns in improving the seismic behavior of confined concrete block masonry walls, an experimental research program is conducted. A total of twelve one-half scale specimens are tested under repeated lateral loads. Specimens are tested to failure with increasing maximum lateral drifts while a vertical axial load was applied and maintained constant. The specimens adopted are two-dimensional (2D) hollow concrete block masonry walls with different parameters such as shear span ratio, inflection point and percent of reinforcement in confining columns and walls. Test results obtained for each specimen include cracking patterns, load-deflection curve, and strains in reinforcement and walls in critical locations. Analysis of test data showed that above parameters generate a considerable effect on the seismic performance of confined concrete block masonry walls.

• Journal of the Earthquake Engineering Society of Korea
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• v.16 no.5
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• pp.1-11
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• 2012

In this paper, non-linear analysis was performed for Reinforced Concrete (RC) walls using different macroscopic models subjected to cyclic loading, and the analytical results were compared with previous experimental studies of RC walls. ASCE41-06 (American Society of Civil Engineers) specifies that the hysteresis behaviors of RC walls are different due to the aspect ratio of the walls. For a comparison between analytical and experimental results, a slender wall with an aspect ratio exceeding 3.0 and a squat wall with an aspect ratio of 1.0 were selected among previous research works. For the non-linear analysis, each test specimen was modeled using two different macroscopic methods: the first representing the flexural behavior of the RC wall, and the second considering the diagonal shear in the web of the wall. Through nonlinear analysis of the considered RC walls, the analytical difference of a slender wall was negligible due to the different macroscopic modeling methods. However, the squat wall was significantly affected by the considered components of the modeling method. For an accurate performance evaluation of the RC building with squat walls, it would be reasonable to use a macroscopic model considering diagonal shear.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.4
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• pp.351-361
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• 2017

Reinforced concrete(RC) structural walls are major lateral load-resisting structural member in building structures. Generally these RC structural walls are coupled with each other by the coupling beams and slabs, and therefore they behave as RC coupled structural wall system. In the design of these coupled structural wall systems, member forces are calculated using elastic structural analysis. These elastic analysis methodologies for the design of coupled structural wall system was not reasonable because it can not consider their ultimate behavior and assure economic feasibility. Performance based design and moment redistribution method to solve these problems is regarded as a reasonable alternative design method for RC coupled structural wall system. However, it is not verified under various design parameters. In this study, nonlinear analysis of RC coupled structural wall system was performed according to various design parameters such as reinforcement ratio, ultimate concrete strain and wall height. Based on analysis results, design considerations for coupled RC structural wall system was proposed.

• 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.

• Geotechnical Engineering
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• v.5 no.1
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• pp.47-60
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• 1989

Lateral earth Pressure distributions due to the ,randy soil backfill behind the rigid vertical walls for three different wall movement modes are obtained by the elasto-plastic finite element analys of soil deformation, and these earth pressures are compared with both Rankine's and Dubrova's active earth pressures. Thereby, the effects of the magnitude and the mode of wall displacement on the earth pressure distribution are investigated. Three different modes of wall movement considered in this study are the rotation about bottom, the rotation about top and the translation. For the case of the wall rotation about top, the earth pressure distribution is shown as a reverse S-curve-shaped distribution due to the arching effect. Consequently, the point of application of the lateral thrust is much higher than one-third of the wall height from the base. And, comparing the other modes of wall movement, the magnitude and the point of appliestion of the lateral thrust for the wall rotation about top are larger and higher, respectively. The wedge-shaped plastic zone in the backfill at active failure is developed only for the mode of wall rotation about bottom. The lateral earth pressure distributions on the walls with inclined backfill of several different slopes are shown for the mode of wall rotation about bottom.

• Journal of Korean Tunnelling and Underground Space Association
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• v.18 no.2
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• pp.155-164
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• 2016

The changes in earth pressure and ground settlement due to the underground excavation nearby the existing retaining wall according to the separation distance between underground excavation and retaining wall, were studied experimentally. A soil tank having 160 cm in length and 120 cm in height, was manufactured to simulate the underground excavation like tunnel by using 5 separated bottom walls. The variation of earth pressure was measured according to the excavation stages by using 10 separated right walls simulating the retaining wall. The results showed that the earth pressure was changed by the lowering of first bottom wall(B1), however the earth pressure was not changed significantly by the lowering of third bottom wall(B3) since B3 had sufficient separation distance from retaining wall. Lowering of first bottom wall(B1) induced the decrease of earth pressure in lower part of retaining wall, on the contrary, lowering of first bottom wall(B1) induced the increase of earth pressure in middle part of retaining wall proving the arching effect.

• Journal of the Korean Geotechnical Society
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• v.31 no.10
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• pp.49-60
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• 2015

Since previous studies on the 3-dimensional earth pressure have been conducted focusing on the stability of wall, it is very difficult to find a study on the load transfer to the adjacent ground induced by the 3-dimensional active displacement. Therefore, in this study, we tried to find out the load transfer to the adjacent ground induced by the 3-dimensional active displacement depending on the size of rectangular wall which was defined by the aspect ratio, that is, the ratio of the height to the width of the wall. 3-dimensional model tests were performed in order to measure the distribution and the magnitude of load transfer to surrounding grounds. The transferred load was 17.9~30.6% less than the difference between the 3-dimensional active earth pressure and earth pressure at rest. The transferred load of both vertical and horizontal was maximum at the boundary of the active wall. The load transfer range depended on the normalized height of the active wall, and it was 0.67~1.29w in horizontal direction and 1.0~3.0h in vertical direction. The transferred load in horizontal was maximum at the height of the wall. As the aspect ratio increases the location of the maximum transferred load points becomes higher. The ratio of the transferred load area of 56~79% at 0.25w in horizontal direction and 50~58% at 1.0~1.5 in vertical direction. Diagrams showing the distribution and the magnitude of the transferred load depending on the aspect ratio were suggested.

• Geotechnical Engineering
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• v.14 no.2
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• pp.31-40
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• 1998

To verify the reinforcing effect of the strips which are inserted in the backfill, but not connected to the face wall, model tests are executed. As the reinforcing effect is expected to reduce the active thrust acting on the retaining wall, test programmes included the measurements of the thrust. As a result. it is ascertained that the active thrusts are reduced by as much as 50%. Besides, efficient arrangement and the optimum length of the strips are verified. And the the number of reinforcing strips are increased, are close to the Rankine's hypothesis.