• Geomechanics and Engineering
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• v.33 no.3
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• pp.301-315
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• 2023

Adopting cohesive soil as geocell-pocket infill materials is not fully accepted by researchers in the field of road engineering. The cohesion that may inhibit the lateral limitation of geocells is a common vital idea that exists within every researcher. However, the influence of infill materials' cohesion on geocell-reinforced performance is still not thoroughly determined. The mechanism behind this still needs to be studied in depth. This study initially discussed the relationship between subgrade bearing capacity, geocells' contribution to reinforced performance, and infill materials' cohesion (IMC). A law was proposed that adopting the soil with high cohesion as infill materials benefited the subgrade bearing capacity, but this was attributed to the superior mechanical properties of infill materials rather than geocells' contribution. Moreover, the vertical and lateral deformation of subgrade, coupling shear stress and confining stress of geocells, and deformation of geocells were deeply studied to analyze the mechanism that high cohesion can inhibit the geocells' contribution. The results indicate that the infill materials with high cohesion result in the total displacement of the subgrade toward to deeper depth, not the lateral direction. These responses decrease the vertical coupling shear stress, confining stress, and normal displacement of geocell walls, which weaken the lateral limitation of geocells.

• Geomechanics and Engineering
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• v.19 no.1
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• pp.71-78
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• 2019

Massive investments are going on to promote and build transportation infrastructure all across the globe with the challenges being more than budgetary. Sandy soils which are predominant in coastal and border areas in India have typical characteristics. The shear strength of such soil is very low which makes it difficult for any kind of geotechnical construction and hence soil stabilization needs to be carried out for such soil conditions. The use of geocells is one of the most economical methods of soil improvement which is used to increase strength and stiffness and reduce the liquefaction potential of the soil. The use of geocells in stabilizing desert sand and results from a series of plate load test on unreinforced soil and geocell reinforced homogenous sand beds are presented in the present study. It also compares the field results using various load class vehicles like heavy load military vehicles on geocell reinforced soils with the experimental results and comes out with the fact that the proposed technique increases the strength and stiffness of sandy soil considerably and provides a solution for preventing settlement and subsidence.

• Geomechanics and Engineering
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• v.32 no.6
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• pp.653-671
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• 2023

In practice, the interference influence caused by adjacent footings of structures on geo-reinforced loose soil has a considerable impact on their behavior. Thus, the goal of this study is to evaluate the behavior of two strip footings in close proximity on both geocell and geogrid reinforced soil with different reinforcement layers. Geocell was made from geogrid material used to compare the performance of cellular and planar reinforcement on the bearing pressure of twin footings. Extensive experimental tests have been performed to attain the optimum embedment depth and vertical distance between reinforcement layers. Particle image velocimetry (PIV) analysis has been conducted to monitor the deformation, tilting and movement of soil particles beneath and between twin footings. Results of tests and PIV technique were verified using finite element modeling (FEM) and the results of both PIV and FEM were used to utilize failure mechanisms and influenced shear strain around the loading region. The results show that the performance of twin footings on geocell-reinforced sand at allowable and ultimate settlement ranges are almost 4% and 25% greater than the same twin footings on the same geogrid-reinforced sand, respectively. By increasing the distance between twin footings, soil particle displacements become smaller than the settlement of the foundations.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.827-832
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• 2003

This study presented the reinforcing effect of sands by using newly devised 3D Tirecell. Plate loading tests for sand were conducted for different relative density and number of reinforced layers. From the tests, the ultimate bearing capacity of reinforced sand increased with increasing relative densities. The effect of reinforced layers with 0.4B interval is limited to 2 layers and further reinforcing effects can not be obtained beyond 3 layers. Especially the bearing capacity increased remarkably at 1 layer of Tirecell reinforcement and the degree of increase was small for 1 layer to 2 layers increase of reinforcement. Test results show that the reinforcing effect of Tirecell is prominent compared with commercial geocell in the literature.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.337-349
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• 2009

In recent years, the cutting and banking areas along the railway in Korea are exposed to the erosion problem during every year. The reinforcement is a composite construction material in which the strength of engineering fill is enhanced by the addition of strong tensile reinforcement in many different types. Various problems of the railway infrastructure have occurred due to the differential settlement, frost heaving, mud pumping, lack of bearing capacity, partially loss of embankment. In advanced countries, railway roadbed reinforcement is applied to solve these problems on railway roadbed. This paper presents the solution of such problems by means of the engineering works incorporated with railway reinforcement infrastructures such as geotextile bag method, existing grouting method, geocell, reinforced earth, soil nailing and so on.

• Journal of the Korean Geosynthetics Society
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• v.12 no.4
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• pp.109-121
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• 2013

This paper studied the characteristics of bearing capacity of railway reinforced with geosynthetic against repetitive loading of train. The railway that was based on the porous pavement substructure ground and reinforced with geosynthetic was copied. In order to analyze load carrying capacity of geosynthetic, we have had 3cases experiments - in the first case, the ground was non reinforced, second case was reinforced geocell and last case was reinforced geogrid - and all of them were reduced-scale laboratory tests. The results of the analyses indicated that the bearing capacity of the reinforced geogrid increases much more than the reinforced geocell. Residual deformation of the initial cyclic load was larger than the secondary cyclic loads.

• Journal of the Korean Geosynthetics Society
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• v.12 no.4
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• pp.1-10
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• 2013

Recently, the closed landfills are usually converted into parks or playground by the check the stability of landfill because they settle unevenly making them unsuitable for structures. When the closed landfill reuse, environmental and structural stability is important. To increase the bearing capacity and reduce the probable settlement of a foundation on waste disposal ground, a layer of geosynthetics(Geocell) is placed on the waste disposal ground. In this paper, the analysis of long-term settlement parameter correlation was performed, also the evaluation of bearing capacity reinforcement effect was conducted by field test. The settlement measured in the field, and input the same ground index when an integer to identify each model were compared by calculating the settlement. In addition, by adjusting the parameters of each model to identify the most similar to the value of field measurement parameters were calculated. Based on the analysis results, when the using the Park's model C(intermediate) = 0.0678, the expected settlement is similar to the field measurement results. Also, the bearing capacity of geocell reinforced ground is 1.193~1.554 times higher than that of unreinforced ground.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.172-176
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• 2011

최근 들어 생활수준의 향상과 친수 환경에 대한 인식이 높아지면서 하천환경의 보전과 개선에 대한 필요성이 증대되고 과거 이수 또는 치수 목저으로 정비되었던 하천을 자연형 하천으로 탈바꿈 시키려는 움직임이 많이 일어 나고 있다. 자연형 하천 공법의 연구는 1990년대부터 점차 이루어 지고 있으나, 호안의 식생 공법 연구 및 수리 실험을 이루어 지지 않는 실정이다. 이제 본 연구에서는 자연형 하천 정비의 대표적인 방법인 호안 사면 처리 공법 중 지오셀 식생 매트에 대한 수리모형 실험을 실시하였다. 고정상 실험을 통하여 활착된 지오셀 식생 매트가 허용할 수 있는 유속과 수위를 정하는데 목적을 두었고, 상사법칙 이론을 도입하여 수행된 실험결과를 정리 분석하였다. 분석된 실험치를 왜곡모형에 적용하여 실제 규모로 환산한 결과 현재 설계시 허용되는 유속에도 지오셀 식생 매트의 안정성이 확보되는 것을 확인할 수 있었다. 따라서 호안의 지오셀 식생매트의 적용이 가능 할 것으로 보이나, 제한적인 실험결과에 의해 왜곡모형을 이용하여 현장조건을 추정한 것이므로 적용 및 해석에 있어서는 실제 설치되는 하천의 복잡한 수리 수문학적인 변수가 충분히 고려되어야 할 것이다.

• Journal of the Korean Geosynthetics Society
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• v.6 no.3
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• pp.39-46
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• 2007

Many industrialized countries of the world have many problems about the reuse of waste landfill area because the increase of terminated waste disposal landfill. Especially, the effective use of the terminated waste disposal landfill nearby the urban area has been demanded, because of the lack of the usable land. However, the reuse of terminated waste disposal landfill site is needed an adequate stabilization of ground for increasing the bearing capacity and reduce the allowable settlement for the given structure. This study is to evaluate the applicability of geosynthetics for the increment of bearing capacity of solid waste landfill ground. The in-situ cyclic plate loading tests were performed to determine the dynamic and static behaviors of reinforced ground with geosynthetics. Four series of test were conducted with variations of geosynthetics, number of geogrid layer. Based on the cyclic plate load test results, the bearing capacity ratio, subgrade modulus of ground, and the elastic rebound ratio were determined.

• Journal of the Korean GEO-environmental Society
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• v.9 no.6
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• pp.5-12
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• 2008

In this research, the plate load tests on sand which is reinforced by Tirecell mat were simulated by finite element method (FEM). Tirecell mat made by waste tires has the same function and similar shape to Geocell for soil reinforcement and it can also be used for civil engineering structure. The results were compared with those of field plate load tests for evaluation of suitability of modeling method. From the comparison of both results, it can be seen that the settlements by FEM were very similar to test results with small margin under the ultimate bearing capacity. For the ultimate bearing capacities of two results, difference was very small. After the confirmation of the modelling, reinforcing effects with variation of cover depth and number of reinforcement layers by Tirecell were analyzed additionally. Reinforcing effect decreases with increasing soil cover depth, and this is similar to previous test results by soil cover depth. As the number of reinforcing layers increased, reinforcing effect increased. However at more than 2 reinforcing layers, reinforcing effect was negligible. In conclusion, the modeling method in this research might be used for analysis of reinforced structures using Tirecell mat.