• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.643-646
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• 2007

As increase of the land price at downtown area, it makes people more and more interested of improving the space utilization such as makes buildings bigger, deeper and higher. Therefore, the importance of the underground construction which is the basic principle has been increased. As constructors have to complete underground construction as soon as possible with the minimum costs, they concentrate on the whole process of underground structure. Although they makes every these efforts, construction failure still happen because of the uncertainty of the condition of soil and the unexpected danger of underground construction. To make matter worse, there are only some examples without detailed information like 'how much this breakdown damage to the construction?' so it is the anther problem that most of people doesn't recognize the economical negative impact of underground structure breakdown. This report would make people understood the importance and risk of the underground construction by showing some analysis which was assumed from the real accidents.

• Journal of Korea Water Resources Association
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• v.36 no.1
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• pp.129-142
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• 2003

In this study, the conduct of underground water flow system with 3 dimensions is interpreted in order to examine closely the actual condition regarding the flow of the underground water which is forecast from the tunnel segment and the interpretation result which selects the design and the construction technique of the tunnel segment was applied. Also, an obstacle to construct that relates with the underground water flow in construction duration in advance will be able to apply with information that is necessary in order to establish the countermeasure. The objective tunnel is the BEOPGI tunnel segment that is 2 parallel tunnels that are a one-way 2 lane and the parameters of the MODFLOW model executing the boring investigation and the permeability examination were presumed. The underground water flow of the excavation tunnel inside was interpreted by the MODFLOW model using the parameters which is presumed and two values which compared with calculated value and observed value are the same almost. Also, when the underground water discharge quantify that followed in tunnel excavation tries to compare, the underground water total discharge quantity from tunnel point of start until destination was presumed as 0.0269㎥/day/$m^2$.

• Proceedings of the Korean Geotechical Society Conference
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• 1994.09a
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• pp.231-234
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• 1994

Concentrated stresses due to the tunnel excavation easily cause failure around opening in the soft rock mass layer. Thus, while excavatng tunnel in the soft rock mass layerm it is very important to predict the possibility of failure or yielding zones around tunnel boundary. There are two typical methods to predict these; 1) the analysis of field monioring data and 2) numerical analysis. In this study, it was attempted to describe the time-dependent or progressive rock mass manner due to the continuous failure and fracturing caused by surrounding underground openings using the second method. In order to apply the effects of progressive failure underground, an iterative technique was used with the Hoek and Brown rock mass failure theory. By developing and simulating, three different shapes of twin tunnels, this research simulated and estimated the proper size of critical pillar width between tunnels, distributed stresses on the tunnel sides, and convergences of tunnel crowns. Moreover, results out progressive failure technique based on the Hoek and Brown theory were compared with the results out of Mohr-Coulomb theory.

• Explosives and Blasting
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• v.35 no.2
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• pp.1-8
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• 2017

In this study, the characteristics of a new rock cracking method using steam pressure are briefly presented. The rock cracking method was originally developed as a means to decrease the ground vibrations from underground rock excavations. The validation tests were also conducted by applying the method to an actual rock tunnel under construction. The ground vibrations were measured in the vicinity of the test site. The measured vibration results were compared with the values predicted by an attenuation equation, which had been proposed by a company in Japan. Also, a simple cost assessment for the method was conducted to demonstrate its cost effectiveness in underground tunnel excavations.

• Journal of Korean Tunnelling and Underground Space Association
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• v.5 no.1
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• pp.89-100
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• 2003

Seismic Reflection Methods (TSP, HSP) have been applied in the junction between 2nd Adit and Main Tunnel (Solan Tunnel) of Youngdiong Railroad (Mt. Dongbaek~Dokye). In this paper, methods and case study will be introduced to predict discontinuties in the tunnel before excavation by the Seismic Reflection Methods (TSP, HSP)and secure construction stability of the tunnel in blasting and excavation.

• Tunnel and Underground Space
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• v.4 no.3
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• pp.237-249
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• 1994

A new type of cut method, called SK-cut, was developed in order to overcome the shortcomings of the conventional V-cut and Burn-cut blasting methods. Total 190 times of test blasts were performed for the evaluation of the efficiency of new blasting method. V-cut, Burn cut and SK-cut were compared by applying them to the excavation of main gallery and construction tunnel of underground oil storage cavern. Test results showed that excavation efficiency of the new method was increased by 5.9~9.8% and that specific charge was reduced to 71~92%.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.428-444
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• 2010

After underground excavation being introduced in dometic, many technologies have been storing up. One of them, measurement, has been recognized as an important item under excavation construction. But, unlike a large-scale construction, it was not been treated importantly at the general small-scale structures with poor ordering and original design was unchanged under construction was normal if the problem didn't occur on monitoring. In this paper, the site which safe and economical management as well as shortening construction period was made effectively using measurement result was introduced. Also, the site which was completed safely with analyzing measurement and reinforcement when unusual symptom happened was introduced. Using measurement result effectively will be able to obtain the safety and prevent unnecessary economical loss.

• Tunnel and Underground Space
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• v.5 no.4
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• pp.347-362
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• 1995

The purpose of this study was that manage effectively the excavation process of the transport tunnel in DONGHAE mine area by investigating the variationof the surface and groundwater flow system around the tunnel and neighbouring villages. Thus, the effect of excavation and water-prrofing process on the water system has been studied through the naked eye survey of the tunnel and the surface outcrop, joint survey, core drilling, the measurement of the surface water quantity, evapotranspiration and precipitation analysis, rock hydraulics approach, the pressure test of boreholes, the variation of the water level, and finally the numerical analysis. From above approachs, we derived the conclusion that the exhaustion of the surface water was not caused by the tunnel excavation on the groundwater system was minimized by effective water proofing process.

• Proceedings of the Korean Geotechical Society Conference
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• 1990.10a
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• pp.97-110
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• 1990

This paper presents a case history of a deep open cut excavation of Nakagawa section for Futuoka Subway construction which adopted observational mettled against boiling failure and completed with success by modifying construction based upon field monitoring. One of the difficult conditions for the excavation was sandy layer with high water pressure which was anticipated boiling failure. The boiling was generally considered as one of the difficult phenomena to work with the observational method because of its unpredictable catastrophic nature. Laboratory experiments showed the existence of the prefailure movements of the ground and the possibility of the application of the observational method against the boiling failure. Construction step was planned to be modified, if necessary, based upon field monitoring and was completed with success.

• Explosives and Blasting
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• v.23 no.2
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• pp.1-14
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• 2005

The Korean Atomic Energy Research Institute is currently planning the construction of an Underground Research Tunnel to carry out research and development related to the disposal of high-level wastes from nuclear reactors used to generate electrical power. This paper discusses the excavation methods used to construct the Canadian Underground Research Laboratory and their application in planning for the construction of a similar underground laboratory and eventually an underground repository for high-level wastes in Korea.