• Journal of the Korean Geotechnical Society
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• v.26 no.1
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• pp.63-73
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• 2010

The supply of high quality filling materials for pavement base course or reclamation is getting harder. So, there is an attempt to use soft mudstones as an earth filling material in Pohang area. But the engineering properties of the soil deposit placed with soft mudstones have not been clearly evaluated yet. We investigated the water absorption and softening, the slaking behavior and the geological mechanism in order to obtain an effective way of estimating the magnitude of land subsidence and the reduction of soil strength. The applicability of soft mudstones is examined by a variety of laboratory tests and pilot-scale field tests. In addition, it is necessary to consider the environmental characteristics of soft mudstones as a reclaiming material, Consequently, the results from the current study can be used to prevent any construction defects due to the careless use of soft mudstones for the pavement base course or reclamation.

• Journal of the Korean Geotechnical Society
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• v.15 no.3
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• pp.17-25
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• 1999

The feasibility of using waste lime, which is produced as a byproduct during the manufacture of sodium carbonate in Inchon, Korea. as a stabilization admixture with weathered granite soil was investigated. Laboratory tests were conducted to determine the chemical composition, pH, compaction characteristics, unconfined compression strength. X-ray diffraction analysis of waste lime and weathered granite soil admixtures. Based on the present tests, it appears that the admixtures are environmentally safe and can be used as landfill material.

• 어항어장
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• s.80
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• pp.43-46
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• 2007

근래 패각이 공공사업 등에 이용되는 사례도 많아지고 있어 용지의 매립재나 연약지반의 개량재, 도로의 동파 억제재 등 여러 가지 용도로 이용되고 있다.

• Journal of the Korean Geotechnical Society
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• v.23 no.8
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• pp.149-158
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• 2007

Recently, the selection of procurement material for reclamation or road at Pohang area is getting harder. so, it is attempted that mudstones are used for road base material and harbor reclamation. But there is no example that use mudstone to reclamation and the features of the reclaimed land using mudstones have not been made clear yet. We will make clear these features-especially the water absorption and softening, slaking behavior and the geological mechanism, so we will obtain the method to forecast a land subsidence and a decline of land strength. In this study, we examined the adaptedness judgment of mudstones as a reclamation material for road basis material or harbor reclamation material through the laboratory test and pilot test.

• Journal of the Korean Geotechnical Society
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• v.26 no.7
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• pp.25-36
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• 2010

Tertiary unconsolidated mudstones spread throughout the eastern coast area. The demand for high quality filling materials in these areas is increasing due to harbors and large-scale residential land development. Rock produced in-situ or near site has been used as road subbase construction or reclamation materials for economical reason, but it is hard to decide appropriateness of quality specification because of its characteristics. The test results showed that unconsolidated rocks are diversely considered according to a different method of the applied geotechnical investigation. Therefore, the site of tertiary unconsolidated mudstones, the classification of rock and evaluation of rock properties that must be evaluated by objective criteria and apply a different set of criteria are needed. In addition, the environmental impact must be considered due to acid mine drainage.

• Journal of the Korean GEO-environmental Society
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• v.11 no.6
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• pp.85-91
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• 2010

As enormous construction projects of land development are carried out around Korea, useful construction materials are needed to perform the construction projects. However, there are no more enough of fill and reclamation materials in our country. That is why the coal ash is expected to be utilized as an alternative material. Since the coal ash has the characteristics of a pozzolan and a selfhardening material, it is adjudged that coal ash has a great possibility to be used as a fill and reclamation material. In this study, grain size analysis, Atterberg limit test, and specific gravity test were performed to examine the physical characteristics of the coal ash about a self-hardening material before utilizing the coal ash in the construction. Compaction test, unconfined compression test, direct shear test, and flexible wall permeability test were conducted to investigate the engineering characteristics according to mixture ratios of fly ash and bottom ash. As a result of the tests, it was confirmed that the mixing ratio 1:1 of fly ash and bottom ash is the most effective to use as a fill and reclamation material. If the mixture of coal ash is used as a backfill material with light weight around structure, it is expected to play a significant role in reducing earth pressure on the back of the structure. As the age of the mixture of coal ash goes by, it intends to decrease the coefficient of permeability. As described above, the coal ash should be considered as an alternative material of fill and reclamation materials since the result of the tests indicates that the coal ash is suitable to a useful material on the construction design.

• Journal of the Korean GEO-environmental Society
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• v.4 no.4
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• pp.53-59
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• 2003

Phosphogypsum is a by-product resulting from the phosphoric acid process for manufacturing fertilizers. It consists mainly of $CaSO_4{\cdot}2H_2O$ and contains some impurities such as $P_2O_5$, $F^-$, and organic substances. Recycling research of phosphogypsum is very limited to a field of study, especially, civil engineering. This study describes an application of phosphogypsum as dredged materials. For this purpose, experiments are performed to evaluate the physicochemical properties and environmental characteristics of dredged clay with phosphogypsum ; sedimentation test, pH, and leaching test. The result of this study are as follows : the settling velocity is increased due to the activity of phosphogypsum. And leaching and radioactive test results are far below than those of regulatory requirement of Waste Management Act in Korea. Therefore phosphogypsum can be used as dredged materials in reclamation.

• Journal of the Korean GEO-environmental Society
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• v.17 no.7
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• pp.35-42
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• 2016

There are many reclamation projects domestically and internationally which requires large quantity of reclaimable materials. To provide enough reclaimable soils which are limited in land, there have been various research focusing on the dredged soils in the marine environments. As a part of this research, a GIS based 3D dredging reclamation visualization program was developed for the volume estimation of dredged soils in 2015. The developed program is based on the digitized spatial information of the site investigation data with a consideration of the reliability of the data. Prior to the validation with the comparisons with the actual dredged volume measurement data, the developed program was compared with the commercial 3D visualization program with 3D visualized results from the test site near the Gunjang harbor. The validation of the developed program was performed in terms of the degree of visualized precision, the sectional and profiling of soil layers and the dredged volume estimation results. Based on the comparisons, both commercial and developed program show similar dredged volume with minor discrepancies in soil layers.

• Proceedings of the Korean Geotechical Society Conference
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• 1997.10a
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• pp.81-88
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• 1997

현재 국내외에서 해안가에 수심이 낮은 지역을 중심으로 대규모 매립공사를 수행하여 주택단지, 항만시설, 공업단지 및 공항부지 등으로 사용하고 있다. 매립재를 양질의 모래로 사용하는 경우 매립방법에 따라 매립토의 조밀정도는 다르나 어떠한 경우든 상당히 느슨하거나 중간정도 느슨한 상태로 존재한다. 이런한 느슨한 사질토는 지진 시 액상화 현상에 민감하고, 낮은 지지력 및 큰 즉시침하를 야기시킨다. 따라서 매립된 느슨한 사질토는 향후 시설될 구조물의 중요도에 따라 개량할 필요가 있다. 본 현장의 준설 매립된 사질토의 지반 개량에 적용된 동다짐의 시험시공중 pounder에 accelerometer를 설치하고 적외선 beam을 이용, 충격시의 pounder의 deccleration과 impact velocity를 측정하였다. 여기에서는 이들 실측치를 근거로 중량물체(pounder)의 동적 거동 및 충격시 과잉간극수압 변화를 살펴보았다.

• Journal of the Korean Geotechnical Society
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• v.15 no.4
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• pp.175-184
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• 1999

Several major land reclamation projects such as the Inchon International Airport construction, Songdo New City construction, LNG Tank and LPG storage construction are underway along the coastal line of Inchon in Korea. This study was carried out to investigate the feasible use of waste lime in the land reclamation projects. Waste lime (hydrated lime) used in this study is produced as a by-product in the manufacturing process of $Na_2CO_3$ from local chemical factory in Inchon. This study presents the characteristics of bearing capacity and settlement on the ground formed by layers of waste lime and dredged soil. From the laboratory and in-situ plate load test, the ultimate bearing capacity by in-situ test was 1.25~1.37 times higher than that of the theoretical ultimate bearing capacity. Based on the settlement analysis by Magset- II, the total settlement of layered ground steadly increased up to the ratio of waste lime depth 0.2 and therefore rapidly increased with the increase of waste lime depth. The results of the present study indicate that the ratio of waste lime depth for reclamation work is about 0.2.