• Geophysics and Geophysical Exploration
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• v.9 no.4
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• pp.291-298
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• 2006

Resistivity method is a practical and effective geophysical technique to detect leakage zones in embankment dams. Generally, resistivity survey conducted along the crest assumes that the embankment dam has a 2D structure. However, the 3D topography of embankments distorts significantly resistivity data measured on anywhere of the dam. In this study, we analyse the influence from 3D effects created by specific dam geometry through the 3D finite element modeling technique. We compared 3D effects when resistivity surveys are carried out on the upstream slope, left edge of the crest, center of the crest, right edge of the crest and downstream slope. We ensure that 3D effect is greatly different according to the location of the survey line and data obtained on the downstream slope are most greatly influenced by 3D dam geometry. Also, resistivity data are more influenced by the electrical resistivity of materials constituting reservoir than 3D effects due to specific dam geometry. Furthermore, using resistivity data synthesized with 3D modeling program for an embankment dam model with leakage zone, we analyse the possibility of leakages detection from 2D resistivity surveys performed along the embankment dam.

• Geomechanics and Engineering
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• v.22 no.2
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• pp.143-152
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• 2020

In this research, soil samples of the Kerman sedimentary basin, Iran, were investigated through laboratory tests such as petrography (Scanning Electron Microscopy (SEM), X-Ray Fluorescence Spectroscopy (XRF) and X-Ray Diffraction (XRD)), physical and mechanical characteristics tests. The soil in this area is dominantly CL. The petrography results showed that the dominant clay mineral is Illite. This soil has made some problems in the earth dams due to the low shear strength. In this study, a set of samples were prepared by adding different amounts of lime. Next, the petrography and strength tests at the optimum moisture content were performed. The results of SEM analysis showed substantial changes in the soil structure after the addition of lime. The primary structure was porous and granular that was changed to a uniform and solid after the lime was added. According to XRD results, dominant mineral in none stabilized soil and stabilized soil are Illite and calcite, respectively. The pozzolanic reaction resulted in the reduction of clay minerals in the stabilized samples and calcite was known as the soil hardener material that led to an increase in soil strength. An increase in the hydrated lime leads to a decrease in their maximum dry unit weight and an increase in their optimum moisture content. Furthermore, increasing the hydrated lime content enhanced the Unconfined Compressive Strength (UCS) and soil's optimum moisture. An increase in the strength is significantly affected by the curing time and hydrated lime contents, as the maximum compressive strength is achieved at 7% hydrated lime. Moreover, the maximum increase in the California Bearing Ratio (CBR) achieved in clay soils mixed with 8% hydrated lime.

• The Journal of Engineering Geology
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• v.15 no.1
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• pp.77-86
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• 2005

CFRD(Concrete Faced Rockfill Dam) is in widespread use because this type of dam has superior characteristics in structural, material aspects comparing with earth cored rockfill dam. On this paper, up-to-date re-searches and techniques are summed up to be available for future needs in design and construction of CFRD. For example, such items as embankment using weak rock, experience of sand-gravel fill CFRD, connecting slab applied between plinth and face slab, raising experience of old dm, inverse filtration problem, environmental friendly zone, thickness and reinforcing of face slab, alluvial foundation treatment, and curb element method, are summarized for understanding of related engineers.

• 한국지구물리탐사학회:학술대회논문집
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• 2008.10a
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• pp.101-106
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• 2008

It is very important to measure reliable properties of each zones in dam for seismic design. But, rock-fill zone which have 80% of total volume and support maintenance mainly during earthquake has little property by field test and seismic design was performed using assumed value. So, it is required that reliable properties have to be evaluated by in-situ test. In this study, surface wave method, which is nondestructive such as SASW and HWAW, was applied to dam to evaluate rock-fill zone of dam. In 2 dams, Vs profiles were evaluated reliably and possibility of suggestion of D/B was verified.

• Korean Journal of Construction Engineering and Management
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• v.8 no.3
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• pp.97-105
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• 2007

In many construction projects, such as dams, highways, airports, buildings, industrial plants, and sewerage and drainage systems earthmoving operation is defined the movements of a certain quantity of earth to alter the surface configuration or conditions so that projects requirement can be met. Accurate calculation of travel time is essential for determining productivity of earthmoving operations, and for ultimately selecting the most cost-effective fleet configuration for executing the work. Also transportation work that utilizes dump truck consists average So in the whole expenses earthmoving operation, and is an important cost factor for cost management. Therefore this study proposes a methodology for optimum transfer speen based on the analysis of factors affecting earthmoving operation in different road types by collecting the sources of dump truck running speeds and considering the main factors affecting the earthmoving operation.

• Geophysics and Geophysical Exploration
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• v.13 no.4
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• pp.397-406
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• 2010

Resistivity method is a practical and effective geophysical technique to detect leakage zones in embankment dams. Generally, resistivity survey conducted along the crest assumes that the embankment dam has a 2D structure. However, the 3D topography of the embankment distorts significantly resistivity data measured on anywhere of the dam. This study evaluates the influence from 3D effects created by specific dam geometry and effects of water level fluctuations through the 3D finite element modeling technique. Also, a comparison between different locations of survey line are carried out, and topographic correction technique is developed for the resistivity data obtained along the embankment dam. Furthermore, using synthetic resistivity data for an embankment dam model with leakage zone, detectability of leakage zones is estimated through 2.5D inversion.

• 한국지구물리탐사학회:학술대회논문집
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• 1999.08a
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• pp.1-20
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• 1999

In Japan, geophysical exploration methods have been widely applied to civil engineering and construction fields for a long time. In particular, seismic refraction has long played a significant role in geotechnical site investigations for tunnels, dams and landslides. However, our growing interest on the social and natural environment makes the methods available and its application fields diversify. Digital technologies such as personal computer have revolutionized our ability to acquire large volumes of data rapidly, and to produce more reliable results for subsurface image. Also, color graphics easily visualizes survey results In a more understandable manner, These days geophysical methods are essential to assessing grouting effects, predicting the front of tunnel cutting face, monitoring the movement, pollution and purification process of groundwater. Now three-dimensional exploration techniques have developed for the site characterization in civil engineering and construction needs.

• 한국지구물리탐사학회:학술대회논문집
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• 2002.09a
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• pp.85-100
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• 2002

This paper deals with a development of combined seismic methods, based on the application of Televiewer and seismic tomography, for the quantitative assessment of reclaimed body or dam at seashores in our county. The underground structure of reclaimed dam is very complex, mainly due to the unexpected exchange of rock fragments with the marine silty mud in conjunction with S.C.P. (Sand Compaction Pile) foundation, so that for several reasons only the use of Televiewer and seismic tomography for general application might not lead to a desirable resolution. Kinds of upgraded measuring and evaluation techniques for that are needed. For examples, a novel strategy for capturing the returning impulses from the outer side of casing plastic pipe is desired to be developed. For the tomograhy, one should be being more focussed on the study of raw data based on the wave propagation theory. In this paper, it is shown that such multidisciplinary approaches can be, by attempting to compare and jointly interpret the results from two methods, much efficient for understanding the reclaimed dam structure.

• Journal of the Korean Geophysical Society
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• v.4 no.1
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• pp.71-84
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• 2001

A study was initiated to investigate whether the groundwaters being discharged into the sea could be used as a possible water resources. This paper presents a preliminary information about the groundwaters being discharged along the shoreline of East Sea. Major discharge sites were selected primarily on the basis of the informaion on surface temperatures of the sea. Hydrogeologic and geographic conditions were also considered in selecting the major discharge sites. The development possibility of the discharging groundwater were estimated roughly, considering populations, industries and social development compatibilities of the selected areas. Groundwater dams and linked usage with surface water were suggested as possible development methods for the groundwaters.. Based on this study, we selected about 60 sites as the major discharge areas and tentatively recommended 6 sites as optimal sites for development of groundwaters being discharged into the sea. However, detailed in-situ hydrogeologic surveys are required prior to the final decision.

• Journal of the Society of Disaster Information
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• v.17 no.1
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• pp.53-59
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• 2021

Purpose & Method: The purpose of this study is the theoretical study on the durability standard of ground structures monitoring sensors. A survey on the durability criteria for construction monitoring sensors of domestic construction companies and the income tax implementation regulations, the standard years of contents such as buildings and the standards of the Public Procurement Service for construction monitoring and construction machinery were analyzed. Result: The durability criterion such as the inclination meter and the strain gauge, which are purchased from the Public Procurement Service prior to installation on the ground structure, is 8 to 10 years. Conclusion: The actual durability analysis by comparing the reliability of various monitoring sensors installed in dams at home and abroad, As a result of comprehensive study on the loss and damage rate of the maintenance monitoring sensor installed in the tunnel, the proper durability period of the built-in type monitoring sensor such as domestic pore pressure meter and earth pressure meter installed in the structure or the ground is 5 to 8 years it seems reasonable.