• Geotechnical Engineering
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• v.11 no.4
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• pp.13-24
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• 1995

Laboratory testings, consisting of soil properties testing and vacuum consolidation testing with and without vertical wick drain, were carried out on five different types of soil to determine soil properties and relationship between settlement and time. One dimensional consolidation teat was performed to determine if this test could be used for predicting the behavior of soils during vacuum consolidation. From the results of this study, the one dimensional consolidation test does not appear to be suitable for predicting the rate of vacuum consolidation without wick drain. However, one dimensional consolidation test reasonably predicts the total settlement of vacuum consolidation without wick drain. In vacuum consolidation, the amount of the settlement for silty soils were more or less the same for both cases, with wick drain and without wick drain, even if the time required for consolidation was considerably different. And, strategic placement of wick drain ensures moisture content and the value of the density are similar throughout the soil sample. However, the presence of wick drain for clay Boils increased the amount of settlement and also shortened the time required for consolidation.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.5
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• pp.813-821
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• 2002

Glass fiber reinforced PET matrix composite was manufactured by rapid press consolidation technique as functions of temperature, pressure and time in pre-heating, consolidation and solidification stages. The optimal manufacturing conditions for this composite were discussed based on the void content, tensile, interlaminar shear and impact properties. In addition, the levels of crystallinity with various manufacturing conditions were measured using differential scanning calorimetry to investigate the mechanical properties of this composite material as a function of crystallinity. Among many processing parameters, the mold temperature and the cooling rate after forming were found to be the most critical factors in determining the level of crystallinity and mechanical properties. The level of crystallinity affects the tensile properties to some degree. However, impact properties are affected much more. It also affects the degree of ductility, which determines the impact energy of this material.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.10a
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• pp.390-393
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• 2008

In this research, we introduce a new process for the consolidation of different types of powders such as metal and ceramic powders by using a magnetic pulsed compaction (MPC). The successful consolidation of many kinds of powers including nanopowder by MPC has been presented. A wide range of experimental studies were carried out for characterizing mechanical properties and microstructure of the MPCed materials. It was found that effective properties of high strength and full density maintaining nanoscal microstructure were achieved. finally, optimization of the compaction parameters and sintering conditions could lead to the good consolidation of powders (metal, ceramic, nano-powder) with higher density, and even further enhanced mechanical properties.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.03b
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• pp.575-582
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• 2000

The flat Dilatometer test(flat DMT) has been known as an in-situ testing method which is simple and robust to use, and reliable for site stratification and evaluation of soil properties. It was designed and proposed by Marchetti in 1975 to characterize the properties of soils. There are many researches that have been done to evaluate the horizontal coefficient of consolidation from the dissipation test results of flat DMT on normally consolidated and slightly overconsolidated clays. The representative estimation methods of estimating the horizontal consolidation coefficient are DMT-C method which uses a C-reading dissipation curve and DMT-A method which uses a A-reading dissipation curve. This paper represents a comparison analysis of those two methods in obtaining the horizontal coefficients of consolidation. The reference values are also obtained by CPTU and other laboratory tests. The applicability of using flat DMT to characterize the consolidation behavior is also reviewed for two sites. According to the results, DMT-A method is not suitable for silty clays possibly because of the compressibility characteristics. As for the normally consolidated and slightly overconsolidated clays, the results obtained from the two methods are comparable with each other as well as with the laboratory test results.

• Geotechnical Engineering
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• v.13 no.1
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• pp.47-58
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• 1997

The predicted consolidation behavior of in-situ soft clay is quite different from the meas ureal one mainly due to the approximate numerical modelling techniques as well as the uncertainties involved in soil properties and geological configurations. In order to improve the prediction, this paper takes the following pinto consideration : an optimization technique should be adopted for characterizing the in-situ properties from measurements and also an equivalent and efficient model be considered to incorporate the actual 3-D effects. The soil parameters used be the modified Camflay model, which have an effect on the process of consolidation, were back-analyzed by BFGS scheme on the basis of settlements and pore pressures measured in real sites. The optimization technique was implemented in a general consolidation analysis program SPINED. By using the program, one may be able to appropriately analyze the timetependent consolidation behavior of soft deposits.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.922-929
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• 2004

In some port construction, a case of reclamation with dredged soil for land use can be found. Even though this is not a new technology, there are some problems on the test method and analysis. The design parameters are still remained to be solved to get accurate prediction. Sedimentation of particle and self-weight consolidation are the most important design parameters in reclamation by dredged soils. The design parameters are influenced by properties of the physical and sedimentation of dredged soils. This influencing factors can be determined depend on the history of long term sedimentation and particle characteristics. Thus, properties of the sedimentation and consolidation are varies depend on the regional geologic formation. In this paper, three different sites with different regional soil properties will be compared in design parameters of sedimentation and self-weight consolidation.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.10a
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• pp.504-507
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• 2002

Glass fiber reinforced PET (Poly-Ethylene-Terephthalate) matrix composite was manufactured by rapid press consolidation technique as functions of temperature, pressure and time in pre-heating, consolidation and solidification stages. The optimal manufacturing conditions for this composite were discussed based on the void content, tensile, interlaminar shear, and impact properties. A tensile test was attempted to investigate the mechanical properties of the composite. It is found that the level of crystallinity and microstructure affects on the tensile properties substantially.

• Journal of the Korean Geotechnical Society
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• v.26 no.1
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• pp.21-33
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• 2010

In this paper, the consolidation and the permeability characteristics of Songdo were evaluated based on the laboratory and field tests. The test results indicate that silty clay layer above approximately E.L-15 m are consolidation layer, and sand layers embedded in consolidation layers are drainage layers. Consolidation layer was overconsolidated state before the reclamation work; however, it transferred to normalized state after the reclamation work. In addition, the average and the range of consolidation properties and magnitude of anisotropy of coefficient of consolidation were evaluated according to the soil types such as clay, silty, and clayey silt since these properties are sensitive to soil types. These analysis results can be used as preliminary design parameters of consolidation and permeability m Songdo area.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2001.10a
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• pp.379-385
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• 2001

A series of standard consolidation tests and repeated loading consolidation tests were peformed with 2 kinds of peat sampled in Chonbuk area to study the consolidation characteristics of peat. The samples had following physical properties : 58% and 72% of organic content, 487% and 685% of natural moisture content and 7.02 and 9.72 of initial void ratio, respectively. And compression index $C_{c}$ and coefficient of secondary consolidation $C_{\alpha}$ were increased steeply when the consolidation load exceed about 2.5 and 3 times of each preload as like the characteristics of peat. The dependance on consolidation pressure of $C_{C}\;and\;C_{\alpha}$ in peatl and the maximum values, 2.9-3.8 and 0.3-0.4 were larger than that of normal clay, respectively.

• Proceedings of the KAIS Fall Conference
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• 2004.06a
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• pp.39-41
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• 2004

The engineering properties of the geomaterial, an essential material in construction engineering, are significantly influenced by consolidation mode, which is called inherent anisotropy. Speically cohesive soils feature the anisotropy mainly due to their flate-like minerals and chemical interactions. In this research, an experimental study was conducted for the investigation of the anisoropy. Three isotropic and four anisotropic consolidated-undrained triaxial compression tests were performed for the cohesive specimens with various stress ratios of consolidation. The effects of the consolidation mode for cohesive soils were presented and investigated in stress-strain behavior, pore water pressure, and undrained shear strength of the test results.