• Magazine of korean Tunnelling and Underground Space Association
• /
• v.26 no.1
• /
• pp.63-85
• /
• 2024

• Explosives and Blasting
• /
• v.34 no.3
• /
• pp.10-16
• /
• 2016

Recently, transition from open pit to underground mining in limestone mines is an increasing trend in Korea due to environmental issues such as noise, dust and vibrations caused by crushers and equipment. The severe damages in the surrounding rock mass of underground opening caused by explosive blasting may lead to rock fall hazards or casualties. It is well known that variables which mainly affect blast-induced rock falls in underground mining are: blast vibration level, joint orientation and distribution and shape of the cross sections of underground structures. In this study, UDEC program, which is a DEM code, is used to simulate blast vibration-induced rock fall in underground openings. Variation of joint space, joint angle and joint normal stiffness was considered to investigate the effect of joint characteristics on the blast vibration-induced rock fall in underground opening. Finally, jointed rock mass models considering blast-induced damage zone were examined to simulate the critical blast vibration value which may cause rock falls in underground opening.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.20 no.4
• /
• pp.671-686
• /
• 2018

Recently, earthquakes have occurred near Gyeongju and Pohang and the social demands are thus being increased for seismic analysis of tall buildings and their adjacent underground structure in big cities. Since most of the previous seismic analysis studies considered a tall building and an adjacent underground structure separately, however, they lack the analysis on dynamic mutual behavior between two structures. Therefore, in this study, a dynamic analysis with a full soil-structure interaction was performed for a complex underground facility with a tall building and an adjacent underground structure constructed on the bedrock with a surface layer. To improve the reliability, in particular, a pseudo-static analysis was performed and compared with the dynamic analysis results. It is comprehensively concluded that the analysis of adjacent underground structures being considered is more conservative than that of not considered.

• Korean Institute of Interior Design Journal
• /
• v.18 no.6
• /
• pp.104-114
• /
• 2009

The purpose of study was understanding necessity of environment design for underground parking lot in residential design plan and grasping design plans of 'Activity Support' that considerate women, exclude women's unsecured feeling at underground parking lot. The inquiry analyzed 6 design plan in design competition that considerate women according to precede studies, a theory of CPTED, a design guide for wayfinding, and survey. A ramp, circulation, entrance, lighting, ventilation, and space design plan are proceed on this study The result are as below. First, a rectilinear figure ramp suits entrance plan on the circulation, but if it is not possible, cross-using of rectilinear and curvilinear figure ramp plan is desirable. Second, on the circulation plan, vehicles circulation plan and equality parking distribution plan got accomplished generally, and help senses of direction because it is planed network systemize. On a large scale underground parking lot, simplify parking circulation to convenience entrance and exit for weak in sense of direction. Third, the shape and material that‘s environmentally conscious will be in use to the entrance plan. As the first stage to the underground, artwork that women prefer can modulate the rejection of underground space. Forth, natural lighting system and ventilation can make the environment-friendly space, decrease the women’s rejection to the underground, it can also keep a natural watch on the space. Fifth, on the space design plan, it can use bright and comfortable design of wall and ground to decrease the women‘s rejection, also it is useful to the sense of direction. LED indirect lighting plan that 58.7% of women prefers on survey reflects women’s state of desire that bright and atmosphere. In addition, proper use of plans that subsidiary facilities, rest area with Sunken, and nature-friendly material can minimize differences of underground and ground parking lot.

• Safety and Health at Work
• /
• v.9 no.1
• /
• pp.10-16
• /
• 2018

Background: A detailed evaluation of the underground mine climate requires extensive measurements to be performed coupled to climatic modeling work. This can be labor-intensive and time-consuming, and consequently impractical for daily work comfort assessments. Therefore, a simple indicator like a heat stress index is needed to enable a quick, valid, and acceptable evaluation of underground climatic conditions on a regular basis. This can be explained by the unending quest to develop a "universal index," which has led to the proliferation of many proposed heat stress indices. Methods: The aim of this research study is to discuss the challenges in identifying and selecting an appropriate heat stress index for thermal planning and management purposes in underground mines. A method is proposed coupled to a defined strategy for selecting and recommending heat stress indices to be used in underground metal mines in the United States and worldwide based on a thermal comfort model. Results: The performance of current heat stress indices used in underground mines varies based on the climatic conditions and the level of activities. Therefore, carefully selecting or establishing an appropriate heat stress index is of paramount importance to ensure the safety, health, and increasing productivity of the underground workers. Conclusion: This method presents an important tool to assess and select the most appropriate index for certain climatic conditions to protect the underground workers from heat-related illnesses. Although complex, the method presents results that are easy to interpret and understand than any of the currently available evaluation methods.

• Tunnel and Underground Space
• /
• v.29 no.1
• /
• pp.30-37
• /
• 2019

Some leading countries in mining have a very quantitative guideline for underground mine opening design which is useful to minimize mine hazards such as rockfall and collapse. Those hazards sometimes can cause a huge damage on human life and property in the mines. Construction guidelines of underground mines in Korea consist of qualitative and general expressions although the workers' safety rules and guides are well provided. Recently, mining operations in Korea are going underground due to the environmental regulations and resource depletion at shallow depth, and therefore there is a growing demand on a specialized and systematic guideline for mine opening design securing the underground stability. In this paper, current status of mining industry, research trends, and mining guidelines in Korea and overseas have been reviewed to give an insight into developing a new Korean guideline for underground mine design.

• Fashion & Textile Research Journal
• /
• v.24 no.5
• /
• pp.493-504
• /
• 2022

This study aims to gain a deeper understanding of the fashion styles of underground rappers in China and South Korea. Due to rappers' fashion influence on modern fashion trends, research on rapper fashion has been conducted steadily in the field of apparel. Qualitative research methodologies including literature research and in-depth interviews were the primary techniques used to solve the research questions. In-depth interviews were conducted with 10 Chinese underground rappers and 10 Korean underground rappers to reveal and explore their fashion style and view of fashion. As a result, the participants' fashion styles were categorized into four styles: authentic hip-hop fashion style, popularized hip-hop fashion style, easy sports casual style, and trendy street style. Rappers from both countries consider that their identity as rappers can be demonstrated through their hip-hop fashion style. The influence of hip-hop culture and the popularity of rap music differs between China and Korea. It affects not only the rapper's musical characteristics, but also their fashion style. While Korean underground rappers' fashions style is trendier, Chinese underground rappers' fashions style displays stronger characteristics of hip-hop fashion. Due to the public's negative view of rappers, some Korean underground rappers intentionally try to hide their identity by wearing a fashion style that differs from the authentic rapper image. Understanding the fashion styles of underground rappers in Korea and China is expected to assist in predicting future hip-hop culture and rapper fashion trends.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.26 no.4
• /
• pp.56-66
• /
• 2023

Safety accidents are increasing, such as changes in groundwater levels due to construction work or natural influences, or ground cave-ins caused by soil runoff from old water supply and sewage pipes. In addition, underground facility management agencies must make efforts to improve the accuracy of underground information through continuous investigation and exploration in accordance with the Special Act on Enhanced Underground Safety Management. Accordingly, in this study, we defined the configuration of equipment and data processing method to collect 3D precise exploration underground facility information and developed 3D underground facility information collection technology to ensure accuracy of underground facilities. As a result of verifying the developed technology, the horizontal accuracy improved by an average of 6cm compared to the existing method, making it possible to acquire 3D underground facility information within the error range of the public survey work regulations.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.26 no.5
• /
• pp.435-448
• /
• 2024

Liquefaction of the ground caused by earthquakes results in significant damage to underground structures such as tunnels, pipelines, manholes, and underground tanks. The uplift of underground structures due to liquefaction has been identified as a major cause of this damage. However, current design practices have not adequately considered the upward displacement of underground structures. This paper proposes an analytical solution based on the limit equilibrium method for cut-and-cover tunnels. Using this solution, a sensitivity analysis was performed on soil cover height, liquefaction depth, ground improvement, and ledge. It was confirmed that the contribution of each factor to the safety factor can be reasonably derived through changes in the safety factor. Although there are still many assumptions and uncertainties that need to be reviewed for their appropriateness, a conservative approach appears to mitigate a significant portion of these uncertainties. This study is meaningful as a stability evaluation method considering the uplift behavior characteristics of underground structures.

• Journal of the Korean GEO-environmental Society
• /
• v.7 no.3
• /
• pp.69-76
• /
• 2006

In this study, an experimental study in sand ground that was prepared by raining method was performed for modeling the bearing capacity behavior of strip footing above a cavity. The critical range of bearing capacity of the strip footing affected by underground cavity was investigated by comparing results between experiment and theory. The size of the critical region depends on several factors such as footing shape, soil property, cavity size and cavity shape. The ultimate bearing capacity was more influenced by the depth of the underground cavity than the eccentricity of the underground. In addition, an underground cavity influences on not only the decrease of the bearing capacity, but also the differential settlement of a strip footing.