• Journal of the Korean Ceramic Society
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• v.29 no.6
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• pp.489-495
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• 1992

The continuous compaction response of zirconia powders prepared by different processing treatments was investigated. Though the yield point could be or not below 1 MPa, the change of slope was always observed at high pressure range around 60 MPa. Powder compaction was mainly governed by second compaction stage and compaction rate was decreased with increasing forming pressure. Rotary vacuum dried powder favored a high compaction density, whereas freeze dried and calcined powders favored an increase in the pressing efficiency. In order to extract more reliable information about powder compaction, it was necessary to use not only compaction response diagram but also compaction rate diagram.

• International Journal of Highway Engineering
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• v.1 no.2
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• pp.135-154
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• 1999

Compaction of asphalt pavement is one of the important processes to make good quality one. There are many laboratory-compaction methods to simulate field compaction, including Marshall compaction, Hveem compaction, gyratory compaction, and etc. The most common method used to determine the fundamental properties of asphalt mixture for design is Marshall method which is using impact energy. However, there is major difference between field compaction using kneading compaction and Marshall compaction using impact energy. Therefore, the gyratory compactor, which currently is the best to simulate the field compaction, was employed. The fundamental properties of asphalt specimen compacted by gyratory compactor and Marshall compactor were determined using laboratory test. From the tests, slag mixture with carbon black or pyrolyzed carbon black showed better performances, such as, in low susceptibility to temperature, high resistance against water and rutting, and high resilient modulus and indirect tensile strength.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.1
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• pp.33-40
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• 2009

Compacted soil are used in almost roadway construction with compaction of soil. The direct consequence of soil compaction is densification, which in turn results in higher strength, lower compressibility, and lower permeability. The standard and modified Proctor tests are the most common methods. Both of these tests utilize impact compaction, although impact compaction shows no resemblance to any type of field compaction and is ineffective for granular soils. It has been dramatic advances in field compaction equipment. Therefore, the Proctor tests no longer represent the maximum achievable field density. The main objectives of this research are a survey of current field compaction equipment, laboratory investigation of compaction characteristics, and field study of compaction characteristics. The findings from the laboratory and compaction program were used to establish preliminary guidelines for suitable laboratory compaction procedures.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.91-96
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• 2002

This study is to analyze the influence of paste flow, compaction time and compaction thickness on the fundamental properties of porous concrete. Results of this study were shown as follows; 1) As paste flow increase, compaction time according to paste flow and compaction thickness decrease. Also, though paste flow is same, as compaction thickness increase, compaction time Increase. So It must be considered that the influence of compaction time according to paste flow and compaction thickness. 2) In the range of this study, compressive strength is the highest value at paste flow 190mm. 3) Occasion of manufactured compactor in this study compaction thickness 10, 15cm is influenced heavily but compaction thickness 20cm is influenced slightly.

• International Journal of Railway
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• v.7 no.3
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• pp.80-84
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• 2014

The purpose of this paper was to review Intelligent Compaction (IC) techniques, which is regarded relatively new to the railroad roadbed construction activity. Most of civil structures are built on roadbed that supposed to provide adequate load bearing support to the upper structure through the qualified compaction process. However, it is not uncommon for structure failure attributed to inadequate compaction control take place in field sites. Unlike traditional compaction control method to check field density at several locations, IC techniques continuously measure various compaction quality indices that represent compaction uniformity. In this paper, a series of literature review relevant to IC techniques was conducted to provide concise summary on the following categories: 1) background of IC technique; 2) Summary of IC vendors and basic principles; 3) modeling of IC behavior, and 4) case study along with correlation between IC with other measurements. In summary, IC technologies seem to be promising in future railroad construction to achieve better compaction quality control so that the serviceability of railroad can be ensured with minimizing rehabilitation and maintenance activities.

• Journal of The Korean Society of Agricultural Engineers
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• v.48 no.6
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• pp.59-67
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• 2006

Particles of soil are crushed when soil is compacted in the in-situ or lab. Among many factors that affect the crush of particles, compaction energy is a major factor. Because the crush of particles can change physical properties, the analysis of effect of compaction energy is very important. In this study, the fragmentation fractals were used for determining the change in grain size distribution and the effect due to change in grain size distribution was estimated. Compaction energy was increased by 50, 100, 200 and 300% based on the energy of standard A compaction test. As a result, grain size distribution curves were changed and fine particles increased as compaction energy were increased. Relative compaction were ranged between $93.38{\sim}107.67$. Fractal dimension of each site increased as compaction energy increased. Relative compaction is proportional to the fractal dimension but coefficients of permeability were in inverse proportional to the involution of fractal dimension.

• The Journal of Engineering Geology
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• v.25 no.2
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• pp.179-188
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• 2015

Although permeating injection is ideal for grouting reservoir embankments, it is usually combined with fracturing injection for grouting, which can disturb the original soil. Compaction with low expansive pressure followed by grout injection can overcome this problem. An expansive compaction (EC) packer was developed in this work to easily apply sequential injection and compaction at a work site. Furthermore, to achieve compaction around the grouting hole, a mixture of expansive admixtures and grout was injected with the EC packer to trigger an increase in volume of the grout material. This work verifies the compaction effect of the EC packer and the expansive admixture. It reports the concepts of the EC packer, the range of expansive compaction, the effectiveness of injection, and the results of indoor tests performed to verify the effectiveness of the expansive admixtures. The indoor testing comprised a preparatory test and the main test. The preparatory test assessed the admixtures for their compaction effects, while the main test measured and analyzed the admixtures' expansive force, pressure, and compaction effect with a mold to verify the effectiveness of the compaction effect.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.301-310
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• 2006

A series of laboratory tests was carried out for analyzing compaction characteristics of hydraulic fill soils(or hydraulically filled soils). Hydraulic fill soils were settled down by the weight of soil particle itself in water and consolidated by the extraction of water from the soil structures. Water content and dry unit weight were observed as the depth of sedimentation and consolidation soil. It was found from the result that the optimum water content $(W_{cpt})$ of the maximum unit weight$(\gamma_{dmax})$ is higher than that of laboratory compaction test(KS F 2312 A method). It was due to difference in compaction energy and compaction effect between two methods. And the maximum dry unit of hydraulic fill soil is smaller than that of laboratory compaction test. Especially in terms of compaction effect, the maximum relative compaction degrees$(R_{cmax})$ of Seamangum dredged sand, river sand and mixed sand, half and half of dredged and river sands, were 85%, 91% and 86%, respectively. It means that the compaction effect can be $85\sim91%$ of the maximum unit weight in laboratory compaction test.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.731-732
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• 2006

Recently warm compaction techniques are focused on and commercialization of one high-density compaction process in the P/M industry. Another development is a new SEGLESS using a developed lubricant that reduces ejection force at room temperature compaction. It is possible to achieve high-density by reducing lubricant amount. In this paper we confirmed that green density was $7.35g/cm^3$ at 686MPa of compaction pressure when the new SEGLESS was applied to relatively lower temperature warm compaction process, such as $80^{\circ}C$.

• Journal of Biosystems Engineering
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• v.31 no.1 s.114
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• pp.24-32
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• 2006

Compaction is becoming a greater concern in crop production and the environment because it can have deleterious effects on growing conditions that are difficult to remediate. Because compaction can vary considerably from point to point within a field, and also from depth to depth within the soil profile, it is important to consider quantification and management of the spatial and vertical variability in soil compaction when developing an overall site-specific crop management plan. In this paper, the importance of soil compaction, techniques for quantification of its variability, and the concept of site-specific tillage are examined. Methods and systems to detect within-field variation in soil strength as a surrogate measure of soil compaction and related soil properties are also compared and discussed. Quantification of variability in soil compaction and site-specific compaction management was motivated recently, and sensors and control systems are still under development. Future study will need to address a number of issues related to understanding and applying the sensor measurements.