• Journal of the Korea institute for structural maintenance and inspection
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• v.9 no.2
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• pp.199-206
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• 2005

In many other countries framed structures with inadequate lateral strength and stiffness have been strengthened by providing reinforced concrete infilled wall. There is a general agreement among researchers those infilled walls have 3-5times greater lateral strength compared with bare frame. The main objective of this research is to investigate the behavior and strength of reinforced concrete frames infilled with concrete block and cast-in-place reinforced concrete panels used for strengthening the structure against seismic action. For this purpose three 1/3 scale, one-bay, one-story reinforced concrete infilled frames were tested under reversed cyclic loading simulating the seismic effect. The results indicate that infilled walls increase both strength and stiffness significantly under lateral loads. Especially Strength capacity and initial stiffness of CIP infilled wall increased 3.8 times and 6.6 times higher than lightly reinforced concrete frame.

• Journal of the Korean GEO-environmental Society
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• v.4 no.1
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• pp.11-17
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• 2003

The existing geotextile reinforced soil wall methods have a demerit in terms of esthetic view because concrete panel or block are used as wall facing of the methods. If grass planting walls could be used in reinforced soil slope or wall methods, efficiency of the methods would be increased with maximization of advantage of the methods. In this study, some possible methods in which grass planting wall is used as wall facing are devised. A series of laboratory model tests were performed to investigate the behavior of newly devised methods in order to compare with the results of each others. As a major result, it was found that this kinds of grass wall facing methods could be accepted as a new construction method even in the sense of stability.

• Journal of the Korea Institute of Building Construction
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• v.17 no.5
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• pp.403-409
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• 2017

In this study, mix proportioning of porous concrete with compressive strength and porosity exceeding 3MPa and 30%, respectively, was examined and then load capacity and flexural toughness of the porous concrete block were evaluated according to the different arrangements of the GFRP bars. To achieve the designed requirements of porous concrete, it can be recommended that water-to-cement ratio and cement-to-coarse aggregate ratio are 25% and 20%, respectively, under the aggregate particle distribution of 15~20mm. The failure mode of porous concrete blocks reinforced with GFRP bars was governed by shear cracks. As a result, very few flexural resistance of the GFRP was expected. However, the enhanced shear strength of porous concrete due to the dowel action of the GFRP bars increased the load capacity and toughness of the blocks. The porous concrete blocks reinforced with one GFRP bar at each compressive and tensile regions had 2.1 times higher load capacity than the companion non-reinforced block and exhibited a high ductile behavior with the ultimate toughness index ($I_{30}$) of 43.4.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.6
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• pp.2866-2871
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• 2011

In this study, computation method of tensile load which develops in tie-bar of reinforced earth, connection strength between tie-bar and eco-block and shear strength of the interface between two eco-blocks were verified by experiments. According to the test results of connection strength test, peak tensile load of D13 deformed bar were close to allowable tensile load of it for situation of infill with soil. Connection strengths of D10 and D13 deformed bars were greater than the allowable tensile load of those respectively for situation of infill with concrete. According to the test results of shear strength of the interface between two eco-blocks, shear resistance parameters, ${\alpha}_u$ and ��${\lambda}_u$ were evaluated as 1.7kN/m and 2$27.6^{\circ}$ respectively.

• Tunnel and Underground Space
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• v.21 no.1
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• pp.20-32
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• 2011

Failure aspects of cut-slope, which induce the sequential collapses during the excavation stage, have been analyzed. Slope rock structures are investigated by examining the orientations and positions of discontinuity planes calculated based on the BIPS image inside the boreholes. Drilled core log has been also used to identify the structural defects. Clay minerals of swelling potentials are detected through XRD analysis. Numerical analysis for slope stability has been performed by utilizing the joint shear strength acquired from the direct joint shear test. Cut-slope collapse characteristics have been studied by investigating the posture of failure-prawn joint planes and the stability of tetrahedral blocks of different sizes. Cross-section analysis has been also performed to analyze the cut-slope behavior and to estimate the amount of reinforcement required to secure the stability of cut-slope. Behavior of reinforced cut-slope is also investigated by analyzing the slope monitoring data.

• Journal of the Korean Geosynthetics Society
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• v.8 no.2
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• pp.21-29
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• 2009

The connection strength between wall facing and geosynthetics should be evaluated by experimental method in the design of reinforced earth wall. However, the evaluation result of connection strength using the typical design method, FHWA(1996) and NCMA(1997), is excessively because of a safety factors. Therefore, this study is conducted in connection strength test between wall facing and geosynthetics, then the test result is applied to the design case by NCMA, FHWA and Soong & Koener(1997). The results confirmed that the evaluation method by Soong & Koener, which is used ultimate connection strength by connection strength test in allowable connection strength, is satisfied with stable in design.

• Journal of the Korean Society for Railway
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• v.15 no.5
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• pp.467-475
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• 2012

Static and dynamic train load tests were conducted to evaluate the train load transfer mechanism in the roadbed which was retained by two types (fully and partially) of segmental retaining walls reinforced by geogrid. The test roadbed was 2.6m high, 5m wide, and 6m long. A combination of earth pressure gages, displacement transducers, and strain gages were placed in specific locations to measure the responses. Test results showed that the wall displacement pattern as well as the earth pressure for the fully reinforced retaining wall was different from those for the partially reinforced retaining wall. In the dynamic train load test, the strain in the upper part of the wall tended to decrease, and both the residual deformation and the rate of the deformation were significantly lower than those in the current design standard.

• Fire Protection Technology
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• s.28
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• pp.37-40
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• 2000

• Journal of the Korean Geosynthetics Society
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• v.11 no.3
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• pp.43-51
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• 2012

This paper describes the stability evaluation of reinforced earth wall using geosynthetic strip based on field test. The wall facing, which is applied in field, is able to present excellent scenery, and the reinforcement has improvement effect of pullout resistance based on rounded band anchor. The measurement is conducted according to construction elapsed time of structure for earth pressure, horizontal displacement of wall facing and reinforcement strain in field test. The evaluation results show that the measured earth pressure is less than theoretical earth pressure due to dispersion effect of earth pressure by geosynthetic strip. The horizontal displacement of wall facing is also satisfied a empirical criteria. The measured strain of reinforcement had nearly no effect on stability of the reinforced earth wall. Therefore, the geosynthetic strip with rounded band anchor can be applied in the reinforced earth wall, and the reinforced earth wall with geosynthetic strip can be commonly used in field because it has a structural stability.

• Journal of the Korean Geosynthetics Society
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• v.18 no.2
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• pp.23-36
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• 2019

In this paper, field measurement of the Block Type Mechanically Stabilized Earth (MSE) wall curved section was performed, and the reinforced area of the curved part is studied through the result. MSE method has been applied to various fields because of easy construction and excellent economic efficiency, so that it can be easily access in our life. However due to lack of compaction and stress concentration phenomenon, cracks and collapse occur in the curve of MSE wall, which is important for safety. The cause of collapse is lack of research on curved section, lack of design criteria, lack of construction due to economical efficiency and shortening of construction period, insufficient compaction space. In this study, therefore, it was examined the existing design and construction standards, analyzed the cause through accident examples of the curved section of the Block Type MSE wall. As a result, the horizontal displacement of the curved section was 90% higher than that of the straight section and 60% higher than that of the concave section. In the case of the convex section in the curved section reinforcement region, the maximum displacement is shown in the H/2 section in the horizontal direction from the center of the MSE wall, and the range of influence from H is shown. In the case of the concave section, the maximum displacement is shown in the center, The minimum displacement was confirmed in H/4 section in the horizontal direction from the center of the MSE wall. As a basic study on the reinforcement area rehabilitation through the actual construction of block type MSE wall, the behaviors of the straight part and the curved part were compared and analyzed. And analyzed the reinforced area in order to reduce the damage of the stress concentration phenomenon and secure the safety.