• Journal of Korean Society of Environmental Engineers
• /
• v.36 no.5
• /
• pp.359-366
• /
• 2014

For an efficient and reasonable management scheme for protecting the soil environment, a soil ecological risk assessment (ERA) method should be developed prior to utilization, based on the contemporary uses and situations of each country. The Korean environmental policy focusing on soil protection is currently accelerating the development of the soil ecological risk assessment method. The soil ERA requires toxicological data on various trophic levels in the soil environment, and ultimately uses PNEC (Predicted No Effect Concentration), which is derived from collected toxicological data. Therefore, test species that are used to generate toxicity data are essential for conducting reliable ERA. This study aimed to select domestic test species for potential use in a reliable Korean ERA. Copper (Cu) and Nickel (Ni) were identified as target substances, with toxicity data (Cu, Ni) and standard test methods being collected to determine candidate species. The candidate species were first classified by soil trophic level, and then sorted into final domestic species. Forty out of 166 domestic species were determined as potential standard test species, whereas 17 out of 120 species were determined as potential Cu and Ni test species. Finally, this study presented potential soil test species based on the characteristics of the domestic soil environment, and established a preliminary step toward developing a reliable Korean soil ERA method.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2003.11a
• /
• pp.373-376
• /
• 2003

A new method measuring soil resistivity in frequency range of 5-500[KHz] using variable frequency inverter was presented, and soil resistivity was analysed by resistive and reactive components on the basis of magnitude and phase of measured ground impedance. The test lead arrangement was proposed to reduce the inductive coupling in test circuit for measuring the soil resistivity. The frequency dependence of soil resistivity was mainly caused by the inductive current flowing through grounding conductors over the frequency of 70[KHz].

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.11 no.12
• /
• pp.5157-5164
• /
• 2010

Currently about 3.2 millon tons of waste lime are accumulated and annually 100,000 tons are producted. This study was carried out to investigate the characteristics of soil mixed with waste lime for reusing of roadbed embanking material. Waste lime used in this study is producted as a by-product in the manufacturing process of making $Na_2CO_3$ from local chemical factory in Incheon. In this study, the feasible reuse of waste lime mixed with granite weathered soil, clay, crushed rock was investigated through laboratory tests including specific gravity test, sieve analysis, hydrometer analysis, atterberg limit test, compaction test, unconfined compressive test, CBR test, permeability test, shear test, and abrasion test. The mixing rate is granite weathered soil, clay, crushed rock 80 % respectively and waste lime 20 % by weight. From the test results, it is shown that the waste lime and soil mixtures satisfy the criteria as road embanking material specification.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.16 no.4
• /
• pp.27-36
• /
• 2012

The simulation of the field dynamic soil properties for soil modeling in the centrifuge test is important. In this study, the process of soil modeling based on the shear wave velocity profile is developed. From the resonant column test in each confining pressure, the shear wave velocity profile is expected and the modeling condition is determined by comparing it with that in the field. During the dynamic centrifuge test, the bender element test is performed for measuring the in-flight shear wave velocity profile, and the applicability of the proposed method was verified. This modeling method is applied to the centrifuge test of the Hualien Large-Scale Seismic test.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2005.10a
• /
• pp.244-244
• /
• 2005

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.7 no.2
• /
• pp.46-51
• /
• 2004

In this paper, reinforcement of soil shear strength by bamboo(substitute materials simulating a root system) are evaluated by soil strength parameters(apparent cohesion(c) and internal friction angle(tan${\Phi}$)), using simple shear tester which clearly depicts shear deformation and controls soil suction. The results show that the internal friction angle does not change under various soil suction conditions but the apparent cohesion, which reach a peak in suction of 45cm$H_2O$ near critical capillary head, is effected by soil suction. And the reinforcement of soil strength by bamboo are expressed by apparent cohesion more than internal friction angle. In addition the increment of apparent cohesion by bamboo reached a peak in suction 45cm$H_2O$ too.

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 1993.10a
• /
• pp.1053-1062
• /
• 1993

The effect of loading speed on soil failure was studied by using a high speed triaxial compression test. Tests were conducted at 0.35-6.2m/s loading speed to compress soil specimens of sandy loam at different moisture contents. The axial stress at fracture increased with increase in loading speed up to certain critical speeds, however they decreased as the speed up to certain critical speeds, however they decreased as the speed increased further. Experiments were also conducted in the field of sandy loam soil with the vibrating tillage tool. Tests were done at 0.33-0.85m/s tractor speed oscillating frequency 13.7hz and oscillating amplitude 59mm. The maximum oscillating velocity of tillage tool was 2.5m/s. It was observed that for the oscillating operation, initially draft slightly increased with increase in forward speed and then it decreased .For the non-oscillating operation, draft increased continuously with increase in forward speed. Approach of studying soil failure in the laboratory test can be related to the field experiments.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2005.03a
• /
• pp.41-48
• /
• 2005

A small scale impact apparatus, pressuremter and soil chamber were used to investigate horizontal behavior and bearing capacity of the steel guardrail post installed in compacted soil. A useful test and data reduction method for pressuremter was developed to evaluate soil parameters of surrounding soil and stability of the post. From the analyses of the PMT, horizontal bearing capacity of the post impacted by a boggie was 12.7% bigger than that of the post with static loading. The increased horizontal bearing capacity is due to generated inertia force that is dependent on the shape of failed soil wedge around the post. P-y curves were obtained from the pressuremeter test and were applied to a finite difference program which predicted a load-deflection and a bending moment contours along the post.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2006.04a
• /
• pp.37-40
• /
• 2006

The batch tests were performed to determine the ratio of hydrogen peroxide on diesel contaminated soil. The objective of test was to determine and optimize the hydrogen peroxide requirements for the remediation of a soil contaminated with diesel fuel. The batch test were done on 5g diesel contaminated soil containing hydrogen peroxide (34.5%). Initial diesel concentration were 2,000mg/kg, 5,000mg/kg, and 10,000mg/kg. The $Diesel(g):H_2O_2(g)$ ratio varied 1:1, 1:10, 1:50, 1:100, with contact reaction time 120 min. Results the batch test, effective ratio of $Diesel(g):H_2O_2(g)$ is 1:100.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2009.03a
• /
• pp.686-691
• /
• 2009

Damage due to frost action in pavement structure system is creating either frost heave or stiffness-weakening of subgrade soil follow melting. The formation of ice lenses requires a frost-susceptible soil, freezing temperatures, and continuous water supply. Eliminating one of these conditions suffices to significantly reduce the intensity of frost action. It is important to know characteristics of subgrade soil in frost susceptibility or decide degree of freezing permission. Also, study on the stiffness variation of subgrade soil during freezing and thawing cycle is very important. In this study, Impact resonance test for subgrade soil at freezing and thawing confirms that is applied for.