• Geotechnical Engineering
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• v.2 no.1
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• pp.45-54
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• 1986

An experimental study was carried out in the laboratory on a model of a reinforced earth retaining wall to provide the empirical data for the rational design and the construction methods on a reinforced earth retaining wall. Observed measurements included the variation of tension in the aluminium foil reinforcing strips was monitored by electrical resistance strain gauges pasted on its at different stages of construction. In addition, the lateral movement of the wall was measured by dial gauges and the mode of collapse of the wall was investigated. The measured values are discussed in comparison with the results of the existing studies of the reinforced earth retaining wall. A significant result of the experiments is that the variation of tension in reinforcing strips is non-linear with the maximum tension occuring close to wall face. Attachment of reinforcement to wall increases the stability against overturning.

• Journal of the Korea institute for structural maintenance and inspection
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• v.5 no.1
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• pp.149-160
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• 2001

In this paper, the stability analyses were performed for masonry retaining wallls in Seoul subway System. This masonry retaining wallls were reinforced with earth anchor system for the construction, but it was removed after construction. Therefore, the stability of masonry retaining wallls should be checked after the earth anchors removed. For stability analysis of masonry retaining wallls. FDM analysis(FLAC Ver.3.3) and slope stability analysis (SLOPE/W) were performed applying the test results from laboratory and field tests(Schmidt hammer test, cack examination). As conclusion, the tension force of earth anchors should be kept, therefore, substitutional method was required in order to keep the tension force of earth anchor system.

• Structural Engineering and Mechanics
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• v.47 no.2
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• pp.227-245
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• 2013

The term "constructability" in regard to cast-in-place concrete construction refers mainly to the ease of reinforcing steel placement. Bar congestion complicates steel placement, hinders concrete placement and as a result leads to improper consolidation of concrete around bars affecting the integrity of the structure. In this paper, a multi-objective approach, based on the non-dominated sorting genetic algorithm (NSGA-II) is developed for optimal design of reinforced concrete cantilever retaining walls, considering minimization of the economic cost and reinforcing bar congestion as the objective functions. The structural model to be optimized involves 35 design variables, which define the geometry, the type of concrete grades, and the reinforcement used. The seismic response of the retaining walls is investigated using the well-known Mononobe-Okabe analysis method to define the dynamic lateral earth pressure. The results obtained from numerical application of the proposed framework demonstrate its capabilities in solving the present multi-objective optimization problem.

• Geotechnical Engineering
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• v.9 no.4
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• pp.45-54
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• 1993

In this paper, the behaviors of reinforced earth retaining walls according to material properties of reinforcement were performed through the centrifuge model tests. Skin element was used flexible aluminum plate in the process of tests. And reinforcements were used with aluminum foil strips and non -woven polyester sheets. As a result of it, model retaining wall utilizing non-woven polyester sheets than aluminum foil strips was supported at high stress level, and maximum horizontal displacement value of skin element was 0.6H height at model walls. In the other hand, coefficient relation diagram for evaluation of horizontal displacement according to skin element location was proposed using test results.

• Journal of the Korean GEO-environmental Society
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• v.19 no.12
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• pp.59-64
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• 2018

The damages to the reinforced earth retaining wall are divided into the front wall, foundation, drainage and upper slope. Damage of reinforced earth retaining wall is mainly caused by damage caused by drainage problem in the field. Recently, damage caused by snow removal materials have been occurred. Recently, the amount of snow removal materials used in winter is increasing due to abnormal weather. This chlorides degrades the concrete structure, where the reinforced earth retaining wall was no exception. There has recently been a case in which the front wall of the reinforced earth retaining wall deteriorates due to the chlorides introduced into the back filling portion through the drainage passage. Therefore, in this study, the cause of damages of reinforced earth retaining wall constructed in bridge abutment was analyzed, and an analytical study was conducted on the countermeasure. As a result, it was found that chlorides, which was introduced through the drainage system in the expansion joint of the bridge shift part or the upper structure, is infiltrated into the back part of the reinforced earth retaining wall and damaged. Therefore, it is suggested to improve the drainage system and restored the stiffness of the front wall.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.372-379
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• 2004

The model tests were conducted to assess the behavior characteristics of geogrid reinforced earth walls according to various surcharge loads and reinforcement spacing. The models were built in the box having dimension, 100cm tall, 140cm long, and 100cm wide. The reinforcement used was geogrid(tensile strength 2.26t/m). Decomposed granite soil(ML) was used as a backfill material. The LVDTs were installed on the model retaining walls to obtain the displacements of the facing. In the results, the maximum displacement of facing and tensile strain of geogrid was measured at 0.7H(H is wall height) from the bottom of reinforced wall.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.6C
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• pp.249-257
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• 2012

The reinforced earth method is financially viable. Furthermore, it overcomes environmental limitations and is therefore employed in retaining walls, slopes, foundations, roads, embankments, and other structures. However, in some cases, reinforced retaining walls are not strong enough in the curved sections and can collapse. Such mishaps are believed to occur because of an unsatisfactory analysis of the curved sections of a reinforced retaining wall. Accordingly, with the aim of investigating the workability and structural safety of curved sections of various types, this study investigates the differences in the estimated horizontal displacements of curved sections of various types and subsequently uses this information to study and analyze preliminary data so that appropriate measures can be taken to resolve alignment issues. The results of an experiment reveal that when a load is applied to curved sections of both concave and convex types, the largest horizontal displacement occurs at the center of the section. In the concave form, the earth pressure force is directed inward, whereas in the convex form, this force is directed outward. As a result, the horizontal displacement in convex forms is larger than that in concave forms. Convex reinforced earth structures are subjected to earth pressures as well as lateral earth pressure, therefore horizontal displacements in convex curved sections is larger than that of concave curved sections.

• Journal of the Korean Geotechnical Society
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• v.16 no.4
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• pp.51-61
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• 2000

This paper reviews fundamentals of a pseudo-static seismic design/analysis method for soil-reinforced segmental retaining walls. A comparative study on NCMA and FHWA seismic design guidelines, which are one of the most well known design guidelines for mechanically stabilized earth walls, was also performed. The results demonstrate that there exist significant discrepancies in the results of external stability analysis despite the same calculation model used in the two guidelines, due primarily to different seismic coefficient selection criteria. It is also demonstrated that the internal stability calculation model for NCMA guideline tends to yield larger seismic reinforcement force in the shallower reinforcement layers, resulting in an increased number of reinforcement layers at the top of reinforced wall and increased reinforcement lengths to ensure adequate anchorage capacity. The internal stability calculation model adopted by FHWA guideline, however, leads to redistribution of dynamic force to the lower reinforcement layers and thus results n an opposite trend of NCMA guideline. Findings from this study clearly demonstrate a need for more in-depth studies to develop a generally acceptable design/analysis method.

• Proceedings of the KSR Conference
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• 2002.10a
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• pp.626-632
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• 2002

Geogrid is widely used as the reinforcement materials in railway earth structures in order to achieve efficient land utilization as well as securing safety in railway service lines in other countries. In this study, the real scale test was carried out to investigate the application of geogrid reinforced soil segmental retaining walls(SRWs) in railway. For this goal, the vibration transfer characteristics of reinforced soil segmental retaining walls was evaluated. The resonant frequencies of SRWs, vertical ground vibration in backfill and vertical/horizontal vibration at segmental units were acquired. This experimental data and analysis result can contribute to understand the vibration response behavior of SRWs.

• Geotechnical Engineering
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• v.2 no.3
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• pp.51-66
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• 1986

The design of fabric reinforced retaining wall structure was discussed in this article. It was confirmed that the reinforced retaining earth wall which was designed by new theoretical formulae developed this time was stable structurally and economically. The plastic fabric filter which was placed in layers behind the facing element reduced the lateral earth pressure on the wall elements in comparison with a conventional retaining earth walls. The reinforcing characteristics of earth wall was governed by the spacing of fabric layers, effective length of fabrics, particle distribution and compaction, and thus it is essential that, in the construction field, the reinforcing strips should be selected in order to develop the maximum friction forces bet.eon soil and fabric filters. The maximum tensile stress developed from the reinforcing strips was appeared at a little far distance from the back of skin element and it was not well agreed with the Rankine's theory but distributed well as a symmetrical shape against the point of the maximum tensile stress. The total length of the different layers should be sufficient so that the tension in the fabric strip could be transferred to the backfill material. Also the total stability of reinforced earth wall should be checked with respect to a failure surface which extended blond the different lathers.