• Geomechanics and Engineering
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• v.18 no.4
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• pp.417-426
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• 2019

Gangue filling in the goaf is an effective measure to control the surface subsidence. However, due to the obvious deformation of gangue compression, the filling effect deserves to be further studied. To this end, the deformation of coal gangue filling in the goaf is analyzed by theoretical analysis, large-scale crushed rock compression test, and field investigation. Through the compression test of crushed rock, the deformation behaviour characteristics and energy dissipation characteristics is obtained and analysed. The influencing factors of gangue filling and predicted amount of main deformation are summarized. Besides, the predicted equation and filling subsidence coefficients of gangue are obtained. The gangue filling effect was monitored by the movement observation of surface rock. Gangue filling can support the roof of the goaf, effectively control the surface subsidence with little influence on the ground villages. The premeter and equations of the main deformation in the gangue filling are verified, and the subsidence coefficient is further reduced by adding cemented material or fine sand. This paper provides a practical and theoretical reference for further development of gangue filling.

• International Journal of Highway Engineering
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• v.16 no.2
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• pp.35-41
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• 2014

PURPOSES : Surface treatment is a favorable method in the pavement preventive maintenance. This study (Part I) aimed to develop the low viscosity filling material for waterproof characteristics and high penetrable and weather resistance, and a series of companion study (Part II) presents the coating characteristics and performance analysis using field and lab tests. METHODS : Hydrophobic characteristics of the advanced surface treatment material are observed and measured the filling depth and the permeability for sand and asphalt pavement specimen using the water absorption test and permeability test, X-RAY CT test. Color difference for the weather resistance using ultraviolet ray accelerated weathering test is compared with asphalt pavement specimens. RESULTS : The developed material shows the decreased water absorption and increased impermeable effect because of the hydrophobic characteristics. It is found that the filling depth is about 6mm and weather resistance is better than asphalt pavement specimen. CONCLUSIONS : The advanced hydrophobic - low viscosity filling treatment material is developed in this study (Part I) to improve the waterproof characteristics and high filling capacity and weather resistance for the pavement preventive maintenance.

• Journal of the Korean Institute of Rural Architecture
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• v.23 no.3
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• pp.1-8
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• 2021

Rural multi-purpose buildings needs to ensure their safety against various disasters. Therefore, a pile foundation, which is a foundation type that can transmit the load of the structure to the bedrock layer, has been designed. The pile foundation method is largely divided into driving piles method and pre-bored pile method. Recently, in order to respond to the Noise and Vibration Control Act and related environmental complaints, construction of pile foundation adopts pre-bored pile method. The bearing capacity of the pre-bored pile method is calculated through a load test in situ. However, a disadvantage stems in that it is difficult to measure the ultimate bearing capacity due to field conditions. Therefore, in this study, the skin frictional force of pre-bored pile was measured through a model test in laboratory for each pile filling material. In result, the pile filling material with using circulating resources shows superior skin frictional force than ordinary portland cement. This study also judged that the result can be applied in place of ordinary Portland cement in the field.

• Journal of the Korean Geosynthetics Society
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• v.11 no.3
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• pp.37-42
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• 2012

The cement paste is mostly used as the filling materials of bored pile in Korea. The use of filling material based on cement paste is inefficient at field construction because it needs a lot of the charging mass. In addition, it has environmental problem according to the large amount of cement use because its strength is also larger than criterion. The excavated soil with stabilizer can be used as the filling materials when the bored pile is constructed. Therefore, this paper describes field application of solidified soil for economical efficiency and environment-friendly. The injection capacity of solidified soil is compared with cement paste's based on unconfined compressive strength test and field load test, and the appropriate of test results is evaluated by design criterion. The evaluation result shows that the capacity of excavated soil with stabilizer is similar to cement paste and the solidified soil is able to apply as filling materials of bored pile because it is satisfied with design criterion.

• Journal of Korean Tunnelling and Underground Space Association
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• v.12 no.1
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• pp.75-85
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• 2010

The focus of this study is to evaluate the field applicability of the newly developed inorganic thixotropic-grout in various ways. In order to do this, the volume stability and the permeability of the inorganic thixotropic-grout have been measured and compared to the existing silica type grouts. In addition, the filling capability of the grout into the tail void has been evaluated through both an experiment with a miniature tail-void filling equipment and a test filling at the shield TBM construction site. The volume loss of the inorganic thixotropic-grout after a 14 day-curing under the atmosphere condition was appeared to be minimal. The excellent waterproofing ability of the inorganic thixotropic-grout was confirmed through a permeability test. The toxicity of the inorganic thixotropic-grout has been evaluated through a toxicity test of aquatic fishes (KS M 0111) and the pH value of the liquid eluviated from inorganic thixotropic-grout was measured as an average of 8.0 and a fatality rate of goldfish after 96 hours was 10% or so. The existence of harmful heavy metals in the liquid eluviated from the inorganic thixotropic-grout has been also examined through an atomic absorption spectroscopy (AAS) test. Any of harmful heavy metals were not detected and the detected level of $Cr^{6+}$ and Cd was far below the standard. Based on both an experiment with a miniature tail-void filling equipment and a test filling at the shield TBM construction site, the filling ability of inorganic thixotropic-grout into the tail void was proved to be excellent.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.593-596
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• 2003

The special amendment agent used in this study is mainly composed of inorganic metal salts such as sodium chloride, magnesium chloride, potassium chloride, calcium chloride, thus is friendly to the environment, and has a function of soil-cement-agent solidification. In this study, a series of laboratory and field experiments including unconfined compressive strength, permeability, pH test, constituent analysis, leaching test were carried out to analyse engineering and environmental characteristics of solidified sludge. The results of this research showed that the solidified sludge could be efficiently used in covering, filling, and planting materials.

• Journal of Conservation Science
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• v.29 no.4
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• pp.395-406
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• 2013

The conservation of damaged object should be restored by the similar material with the original and they have to reversibility as possible as. The characteristics of Buddhist mural paintings composed of clay are with soft material. So far, there have been a number of researches done on filling material that reinforces cracks and exfoliation of mural painting. Based on the application of traditional materials, it was found that they are appropriate to various applications. However, only based on those research results, there are some constraints to the application in the field. In addition, there has been only a few researches done on physical characteristics of filling materials. A major issue is that there is not any standard established on various mixing ratio, which is required for treatment of mural painting. This study was carried out to understand the physical characteristics of filling materials on clay mural painting. The 1st test was conducted to analyze test specimen in twelve different conditions by varying soil mixing ratio and organic medium. The 2nd test was conducted to manufacture filling materials appropriate to the mural painting, based on the result of stable condition from the 1st test, and which was applied to treatment in field.

• Geomechanics and Engineering
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• v.15 no.6
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• pp.1143-1151
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• 2018

Loess often causes problems when used as a filling material in the construction of foundations. Therefore, the compaction technique, shear behavior, and bearing capacity of a filled foundation should be carefully considered. A series of tests was performed in this study to obtain effective compaction techniques and construction parameters. The results indicated that loess is strongly sensitive to water. Thus, the soil moisture content should be kept within 12%-14% when it is used as a filling material. The vibrating-dynamic combination compaction technique is effective and has fewer limitations than other methods. In addition, the shear strength of the compacted loess was found to increase linearly with the degree of compaction, and the soil's compressibility decreased rapidly with an increase in the degree of compaction when the degree of compaction was less than 95%. Finally, the characteristic value of the bearing capacity increased with an increase in the degree of compaction in a ladder-type way when the degree of compaction was within 92%-95%. Based on the test data, this paper could be used as a reference in the selection of construction designs in similar engineering projects.

• Journal of The Korean Society of Agricultural Engineers
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• v.48 no.5
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• pp.73-80
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• 2006

The mono-layer cover system is composed of soils only as a filling material and various plants are planted on the surface to control the water balance in the cover system. In this paper, the mono-layer cover system was considered as an alternative landfill final cover system and developed a model that could utilize industrial by-product (especially, coal ash & phosphogypsum) as additive filling materials. The mixture of granite soil, coal ash, and phosphogypsum was placed as a cover material in a box constructed with cement. Laboratory tests were carried out to investigate the environmental effect on the utilization of coal ash & phosphogypsum and to determine the mxing ratio of each materials. In the leaching test, all materials showed lower heavy metal concentration than the threshold values of regulation. The optimum mixing ratio of materials which was applied to field model test was determined to soil (4) : coal ash (1) : phosphogypsum (1) on the volume base. Field model tests were continued from February to July, 2004 in the soil box that was constructed with cement block. It was verified that coal ash and phospogypsum mixed with soil was to be safe environmentally and the water balance of mono-layer cover system was reasonable.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.23-29
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• 2009

A sand-cone method is commonly used to determine the density of the compacted soils. This method uses a calibration container to determine the bulk-density of the sand for use in the test. The density of the test or compacted soil is computed on the assumption that the calibration container has approximately the same size or volume and allows the sand to fall approximately the same height as a test hole in the field. However, in most cases the size or shape of test hole is not exactly the same as the calibration container. There is certain discrepancy between sand particle settlement or arrangement in the laboratory calibration and in the field testing, which may cause an erroneous determination of in-situ density. The sand filling process is simulated in the laboratory and its effect on the determination of density is investigated. Artificially-made holes with different heights and bottom shapes are prepared to simulate various shapes of the test hole in the field. The sands with different gradations are used in the testing to examine how sand grain size influences the determination of density in the field.