• Geomechanics and Engineering
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• v.9 no.2
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• pp.219-241
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• 2015

In this paper, a series of repeated load tests were carried out on a 150 mm diameter plate simulative of vehicle passes, to demonstrate the benefits of soil-rubber shred mixture in decreasing the soil surface settlement of road embankment. The results show that the efficiency of rubber reinforcement is significantly a function of the rubber content, thickness of rubber-soil mixture and soil cap thickness over the mixture. Minimum surface settlement is provided by 2.5% of rubber in rubber-soil mixture, the thickness of mixture layer and soil cap of 0.5 times the loading surface diameter, giving values of 0.32-0.68 times those obtained in the unreinforced system for low and high values of amplitude of repeated load. In this installation, in contrast with unreinforced bed that shows unstable response, the rate of enhancement in settlement decreases significantly as the number of loading cycles increase and system behaves resiliently without undergoing plastic deformation. The findings encourage the use of rubber shreds obtained from non-reusable tires as a viable material in road works.

• Korean Journal of Agricultural Science
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• v.12 no.2
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• pp.282-291
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• 1985

In order to investigate the settlement characteristics of fill dam with decomposed granite is used as a embankment material instead of conventional clay collected behavoir of Andong dam and analyzed. Andong dam is the use of decomposed granite in the embankment material, and various type of gauges were installed in dam to measure a pore pressure, interval vertical settlement, dam crest settlement, relative settlement, surface settlement and internal horizontal movement. The results were summerized as follows; 1. With the increase of embankment loading, the settlement of core zone during construction increased with linear and under the effective stress $7kg/cm^2$ vertical settlement ratio ranged between 0.1 and 0.8% approximately and showed smaller value than that of fill dam with clay were used as a embankment material. 2. Though embankment loading was increased with about over central part of embankment height, the settlement of core zone in the lower part of the embankment was influenced slightly. 3. Pore pressure responsed sensitively with the increase of coefficient of permeability in core zone and settlement increased with pore pressure were dispersed. 4. During construction relative settlement in the lower part of the embankment has the largest influence on magnitude of the relative density and after construction settlement showed larger value in the core zone which has the largest compression height. 5. Settlement distribution of dam crest showed larger value in the central part, maximum section of dam, but smaller value in near the abutment.

• Journal of the Korean Geotechnical Society
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• v.19 no.1
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• pp.5-19
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• 2003

A series of centrifuge model tests were conducted to investigate the behavior of piled bridge abutments subjected to lateral soil movements induced by approach embankments. The effect of clay layer depth and the rate of embankment construction on piled bridge abutments are the main focus of this study. Tests were performed for two loading types: (1) incremental loading applied in six lifts to the final embankment height; (2) instant loading corresponding to the final embankment height applied in one lift quickly. A variety of instrumentations such as LVDTs, strain gauges, earth pressure transducers, and pore pressure transducers are installed in designed positions in order to clarify the soil-pile interaction and the short- and long-term behavior for piled bridge abutments adjacent to surcharge loads. Based on the results of a series of centrifuge model tests, the distribution of lateral flow induced by staged embankment construction has trapezoidal distribution. The maximum lateral soil pressure is about 0.75$\gamma$H at surcharge loading stage, and about 0.35 $\gamma$H at over 80% consolidated stage.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.1695-1704
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• 2008

The problems associated with constructing high-speed concrete track embankments over soft compressible soil has lead to the development and/or extensive use of many of the ground improvement techniques used today. Drains, surcharge loading, and geosynthetic reinforcement, have all been used to solve the settlement and embankment stability issues associated with construction on soft soils. However, when time constraints are critical to the success of the project, owners have resorted to another innovative approach. Especially, the design criteria of residual settlement is limited as 30mm for concrete track embankment, it is very difficult to satisfy this standard using the former construction method. Pile net method consist of vertical columns that are designed to transfer the load of the embankment through the soft compressible soil layer to a firm foundation and one or more layers of geosynthetic reinforcement placed between the top of the columns and the bottom of the embankment. This paper will present the guidelines for the design of pile net method to supported embankments. These guidelines were developed based on a review of current design methodologies and a parametric study of design variables using numerical modeling.

• The Journal of Engineering Geology
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• v.25 no.4
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• pp.547-555
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• 2015

This work investigated the geotechnical characteristics of an embankment constructed with a mixture of soil and waste lime. The waste lime was a by-product of the manufacture of Na₂CO₃ at a near by chemical factory in Incheon. Field measurements were take three years after construction, and included geotechnical tests such as field density measurement, plate loading testing, dynamic cone penetration testing, and field CBR measurement. The results indicate that the geotechnical characteristics of waste lime mixtures are suitable for embankment works.

• Journal of the Korean GEO-environmental Society
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• v.22 no.3
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• pp.45-51
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• 2021

The evaluation of the degree of compaction of the embankment area, which accounts for most of highway earthworks, is generally performed by a flat plate loading test. The plate loading test is a traditional test method and has high reliability in the field. However, as reaction force equipment must be carried out and it takes about 40 minutes per site during the test, there may be limitations in managing the entire expanse of earthworks. Meanwhile, in order to overcome this, the Ministry of Land, Infrastructure and Transport proposed a simple method of evaluating the level of compactness in the provisional guidelines for compaction management of the packaging infrastructure in 2010. However, it has not been utilized at the highway construction site until now, 10 years later. Therefore, this study attempted to verify the utility of the compaction evaluation method using LFWD (Light Falling Weight Deflectometer) of the impact loading method among the test methods suggested in the provisional guideline. To this end, the correlation was derived by conducting a plate loading test and an LFWD test for each site property and compaction degree. As a result of the test, there was no consistency of test data in the ground with a relative compaction of 80% or less. However, it was confirmed that the correlation has a tendency to increase beyond that. If the test method or test equipment is improved to ensure the consistency of the test values of the impact loading method in the future, it will play a big role in solving the blind spot for compaction management in the earthworks.

• The Journal of Engineering Geology
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• v.20 no.2
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• pp.191-202
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• 2010

In this study, the relationship between the settlements and the horizontal displacements according to embankment was analyzed at the marine sedimentary grounds for preparation of a site, and then the empirical equations of both the settlement and the horizontal displacement considering the embankment load and the thickness were proposed. To do this, the field and laboratory tests were performed at the improvement section where the pre-loading method was applied, and the field monitoring was performed using various sensors. Based on the results of the tests and monitoring, the ground deposits, soil characteristics and engineering properties were analyzed and the settlements and lateral movements were estimated by the Regression analysis. The ground deposits from the ground surface were composed of reclaimed soils, sedimentary soils and based rocks. The thickness of clay in the sedimentary soils layer was ranged from 3.9 m to 44.5 m. The embankment heights to improve the ground during pre-loading were constructed from 4.7 m to 7.8 m in each section. The settlements during embankment were ranged from 0.959 m to 2.217 m and the lateral movements were ranged from 0.048 m to 0.313 m. As the result of regression analysis, the equations of settlements and horizontal displacements according to embankments may be proposed as $s=0.02h^2+0.11h$ and ${\delta}=0.01e^{0.37h}$, respectively. The proposed empirical equations of the settlements and the horizontal displacements according to embankment on the marine sedimentary ground may be applied to the site where has a similar condition of study area.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1673-1677
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• 2008

A method of construction with a basis treatment that uses a latticed bamboo mat puts bamboo's peculiarity and bamboo mat's bending substance to use, and a latticed bamboo mat equally distributes to embankment loading in a basis ground. Therefore it prevents ground destruction by an ill-balanced load and an irregular ground subsidence, and it makes safety system. This investigation make progress a soil box model by a dredged reclamation ground of west and south sea at domestic area, and make a comparative study and analyze the strengthening effect based on a grid size of a bamboo-mat and ground failure that it will use in the field.

• Journal of the Earthquake Engineering Society of Korea
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• v.21 no.5
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• pp.255-264
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• 2017

Dynamic numerical simulation of pile-supported slab track system embedded in a soft soil and embankment was performed. 3D model was formulated in a time domain to consider the non-linearity of soil by utilizing FLAC 3D, which is a finite difference method program. Soil non-linearity was simulated by adopting the hysteric damping model and liner elements, which could consider soil-pile interface. The long period seismic loads, Hachinohe type strong motions, were applied for estimating seismic respose of the system, Parametric study was carried out by changing subsoil layer profile, embankment height and seismic loading conditions. The most of horizontal permanent displacement was initiated by slope failure. Increase of the embedded height and thickness of the soft soil layer leads increase of member forces of PHC piles; bending moment, and axial force. Finally, basic guidelines for designing pile-supported slab track system under seismic loading are recommended based on the analysis results.

• Geomechanics and Engineering
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• v.3 no.2
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• pp.117-130
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• 2011

The methods of design available for geocell-supported embankments are very few. Two of the earlier methods are considered in this paper and a third method is proposed and compared with them. In the first method called slip line method, plastic bearing failure of the soil was assumed and the additional resistance due to geocell layer is calculated using a non-symmetric slip line field in the soft foundation soil. In the second method based on slope stability analysis, general-purpose slope stability program was used to design the geocell mattress of required strength for embankment. In the third method proposed in this paper, geocell reinforcement is designed based on the plane strain finite element analysis of embankments. The geocell layer is modelled as an equivalent composite layer with modified strength and stiffness values. The strength and dimensions of geocell layer is estimated for the required bearing capacity or permissible deformations. These three design methods are compared through a design example. It is observed that the design method based on finite element simulations is most comprehensive because it addresses the issue of permissible deformations and also gives complete stress, deformation and strain behaviour of the embankment under given loading conditions.