• Geomechanics and Engineering
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• 제29권3호
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• pp.291-300
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• 2022

Tunnel boring machines combined with the earth pressure balanced shield method (EPB shield TBMs) have been adopted in urban areas as they allow excavation of tunnels with limited ground deformation through continuous and repetitive excavation and support. Nevertheless, the expansion of TBM construction requires much more minor and exquisitely controlled surface settlement to prevent economic loss. Several parametric studies controlling the tunnel's geometry, ground properties, and TBM operational factors assuming ordinary conditions for EPB shield TBM excavation have been conducted, but the impact of excessive excavation on the induced settlement has not been adequately studied. This study conducted a numerical evaluation of surface settlement induced by the ground loss from face imbalance, excessive excavation, and tail void grouting. The numerical model was constructed using FLAC3D and validated by comparing its result with the field data from literature. Then, parametric studies were conducted by controlling the ground stiffness, face pressure, tail void grouting pressure, and additional volume of muck discharge. As a result, the contribution of these operational factors to the surface settlement appeared differently depending on the ground stiffness. Except for the ground stiffness as the dominant factor, the order of variation of surface settlement was investigated, and the volume of additional muck discharge was found to be the largest, followed by the face pressure and tail void grouting pressure. The results from this study are expected to contribute to the development of settlement prediction models and understanding the surface settlement behavior induced by TBM excavation.

• 건축역사연구
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• 제9권1호
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• pp.27-46
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• 2000

This study aims at examining the background and development process of Masan city after Koryo Dynasty, making a reconstructive map of Original Masan using the first registration maps made in 1912 and analyzing the urban structure of the Original Masan area. The origin of Masan city went back to Koryo dynasty. Around 1040 Koryo government placed an official shipping facility in Masan to transport the taxed grain to the capital city. After that Masan became an important port covering the southern part of KyungSang-Do. And the urbanization of the Original Masan began to bud after a shipping facility was again established by the Chosun Dynasty in 1760 and strengthened in the 19th century after the social standing system was broken and many peasants moved to cities as daily workers. In 1899 Masan was forced to be opened to foreign powers and they placed an international settlement distanced from the area(Original Masan). After this many Japanese advanced to the international settlement and further to the area. The advancement of Japanese brought a critical change in the urban structure of the area. Land was owned by Japanese and many modern sysytems were introduced such as modern buildings, new roads, railroad and modern factories. According to the reconstructive map of the area, 80.5% of land lots are less than $200m^2$ showing the size of each land lot is comparatively small. And Japanese occupied 31.5% of the land in the area. Their land was located on the stratigic points near the port and the center of commerce. The ratio of the road area to the whole land was around 14%, not so low for urban areas in that time. The reconstructive map reveals the exact coastline of the year 1912 erased now due to filling the sea and extending the land, Present Masan city has been developed having the Original Masan as its nucleus. The area has been always the center of urban activities for Masan city. Making an exact reconstructive map for the area and analyzing the urban structure of the area in 1912 is a very important work to understand Masan city wholy.

• 한국산학기술학회논문지
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• 제22권5호
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• pp.241-250
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• 2021

본 연구의 목적은 근대역사환경으로서 도시조직을 이해하고 이를 보전 및 활용하기 위한 지구단위계획의 내용과 실행 사례를 검토하여 향후 시사점을 제시하는 것이다. 본 연구의 방법은 사례 연구이며, 인천시 구도심의 경험을 토대로 도시의 보전을 위한 지구단위계획의 역할과 의미를 살펴보았다. 이에 첫째, 인천 구도심은 개항과 조계지가 그 시작이며, 일본조계, 청국조계, 각국공동조계 등 각기 다른 도시조직의 특성을 가지고 있었다. 둘째, 이러한 도시조직의 보전을 유도하기 위하여 지구단위계획 내 지침으로 가구 계획과 획지 계획, 심의제도를 수립하였다. 셋째, 보전 지침이 미친 영향으로 대상지 내 골목길과 옛 해안선 등 가로와 세장형이라는 필지의 형태, 건물의 외관 요소 등을 보전 및 활용하였다. 이러한 분석을 바탕으로 향후 지구단위계획의 수립 및 재정비 시, 시사점을 도출하였다. 첫째, 조계지 내 역사적 가치를 지닌 가로의 추가적인 발굴이 필요하다. 둘째, 조계지 내 필지의 경우, 고유한 형태적 특성을 유지하기 위해 대형 개발을 제한한다. 셋째, 건물의 외관은 보전 및 활용을 유도하기 위하여 계획적 인센티브를 마련한다.

• 한국산학기술학회논문지
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• 제16권6호
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• pp.4284-4290
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• 2015

최근 도심형 연안정주지역은 전통적인 산업기능 쇠퇴와 부동산경기 침체로 전면개발방식보다는 역사적 문화적 가치를 활용한 재생방식으로 추진되고 있다. 본 연구에서는 부산시 영도구 영도대교 주변 수변지역의 지역자산을 조사하여 물리적 사회적 경제적 자산으로 분류한 후, 이지역의 장소가치를 높일 수 있는 통합적 재생방안을 제시하였다. 첫째, 물리적 재생은 장소와 문화적 특성을 둘째, 사회적 재생은 스토리텔링을 통한 지역브랜드를 셋째, 경제적 재생은 역사 문화적 특성을 고려하여 지역 활성화 방안을 제시하였다. 이를 통한 문화관광 인프라 구축으로 지역자산 기반형 문화체험을 제공하고, 연안정주지 일원의 도시 활력 기반을 제공함으로써 지역경제와 지역 커뮤니티 활성화를 기대할 수 있다.

• 농촌계획
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• 제18권3호
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• pp.25-41
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• 2012

The purpose of this study is to quantitatively analyze the social welfare value given to the designated rural settlement zone by the resident-participated site unit plan that the City of Cheongju is newly attempting to draft. Firstly, the costs and benefits from the site unit planning were estimated. Secondly, through literature review especially focussed on the benefit and cost estimation, on-site questionnaire was designed, and then sample residents of the qualifying sites were asked about their willingness to pay, which could make it possible to estimate the monetary value of its benefits by the contingent valuation method (CVM). Finally, the present value of net benefits (PVNB) was estimated through the derived costs and benefits. As a result of analysis, firstly, the present value of net benefits (PVNB) was found to be 7,641 billion won, which indicated that the implementation of district-unit plan would be able to cause sufficient social welfare value for the effected residents. Secondly, in examining the result of individual average amount for willingness to pay through the CVM, the area that benefited the most was found to be the road improvement. Thirdly, as a result of sensitivity analysis, the parameter with the most effects was the discount rate, which suggested that, in carrying out public projects, excessive market interest rates would not be appropriate.

• Geomechanics and Engineering
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• 제21권2호
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• pp.153-164
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• 2020

Tunnel excavation in shallow soft ground conditions of urban areas experiences inevitable surface settlements that threaten the stability of nearby infrastructures. Surface settlements during shield TBM tunneling are related to a number of factors including geotechnical conditions, tunnel geometry and excavation methods. In this paper, a database collected from a construction section of Hong Kong subway was used to analyze the correlation of settlement-inducing factors and surface settlements monitored at different locations of a transverse trough. The Pearson correlation analysis result revealed a correlation between the factors in consideration. Factors such as the face pressure, advance speed, thrust force, cutter torque, twin tunnel distance and ground water level presented a modest correlation with the surface settlement, while no significant trends between the other factors and the surface settlements were observed. It can be concluded that an integrated effect of the settlement-inducing factors should be related to the magnitude of surface settlements.

• Geomechanics and Engineering
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• 제33권5호
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• pp.463-475
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• 2023

Tunnel construction activity, conducted mainly in mountains and within urban centres, causes soil settlement, thus requiring the relevant management of slopes and structures as well as evaluations of risk and stability. Accordingly, in this study we performed a three-dimensional finite element analysis to examine the behaviour of piles and pile cap stability when a tunnel passes near the bottom of the foundation of a pile group connected by a pile cap. We examined the results via numerical analysis considering different conditions for reinforcement of the ground between the tunnel and the pile foundation. The numerical analysis assessed the angular distortion of the pile cap, pile settlement, axial force, shear stress, relative displacement, and volume loss due to tunnel excavation, and pile cap stability was evaluated based on Son and Cording's evaluation criterion for damage to adjacent structures. The pile located closest to the tunnel under the condition of no ground reinforcement exhibited pile head settlement approximately 70% greater than that of the pile located farthest from the tunnel under the condition of greatest ground reinforcement. Additionally, pile head settlement was greatest when the largest volume loss occurred, being approximately 18% greater than pile head settlement under the condition having the smallest volume loss. This paper closely examines the main factors influencing the behaviour of a pile group connected by a pile cap for three ground reinforcement conditions and presents an evaluation of pile cap stability.

• 한국농촌건축학회논문집
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• 제13권3호
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• pp.99-106
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• 2011

The purpose of this paper is to examine their degree of housing satisfaction in Gyeongju, focused on indoor environment of urban traditional houses. Mostly built during time period from 1930's to 1980's in Seoak-dong, Bomun-dong, Namsan-dong, Sajeong-dong, and Hwangnam-dong, Gyeongju' Hanok reveals the evolutionary development to fit into the urban settlement. Urban traditional house has important meaning as a type of residence maintaining tradition of Korean residential culture, and it is the study's first goal to derive developable element by analyzing the characteristics of urban traditional house focusing on such a feature. Residents in 5 districts in Gyeongju were classified and the self-administered questionnaires were provided to them. 187 papers were used for final analysis. The data for general trend of satisfaction was seek for after its average and standard variation were calculated.

• Geomechanics and Engineering
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• 제36권2호
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• pp.131-143
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• 2024

Shield tunneling construction commonly crosses underground pipelines in urban areas, resulting in soil loss and followed deformation of grounds and pipelines nearby, which may threaten the safe operation of shield tunneling. This paper investigated the pipeline deformation caused by double curved shield tunnels in soil-rock composite stratum in Nanjing, China. The stratum settlement equation was modified to consider the double shield tunneling. Moreover, a three dimensional finite element model was established to explore the effects of hard-layer ratio, tunnel curvature radius, pipeline buried depth and other influencing factors. The results indicate the subsequent shield tunnel would cause secondary disturbance to the soil around the preceding tunnel, resulting in increased pipeline and ground surface settlement above the preceding tunnel. The settlement and stress of the pipeline increased gradually as buried depth of the pipeline increased or the hard-layer ratio (the ratio of hard-rock layer thickness to shield tunnel diameter within the range of the tunnel face) decreased. The modified settlement calculation equation was consistent with the measured data, which can be applied to the settlement calculation of ground surface and pipeline settlement. The modified coefficients a and b ranged from 0.45 to 0.95 and 0.90 to 1.25, respectively. Moreover, the hard-layer ratio had the most significant influence on the pipeline settlement, but the tunnel curvature radius and the included angle between pipeline and tunnel axis played a dominant role in the scope of the pipeline settlement deformation.

• 한국지역지리학회지
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• 제17권5호
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• pp.582-599
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• 2011

본 연구에서는 전포돌산공원을 대상으로, 공동체를 위한 공공공간이 절대적으로 부족한 도시 저소득층 거주지역의 공원 재생과정에서 나타나는 주민들의 갈등과 참여 그리고 공원에서 행해지는 주민들의 다양한 활동을 살펴보았다. 그리고 이를 통하여 새롭게 재생된 도시 소공원이 주민들의 일상에 미치는 영향 그리고 이들에게 공원의 역할과 의미는 무엇인지를 파악하고자 하였다. 돌산공원은 일반적인 도시 소공원의 기능을 제공할 뿐만 아니라 불량경관의 개선, 토론 집회를 위한 장소 제공, 문화 및 참여공간으로서의 역할을 수행하며 개방적인 마을분위기 형성, 공동체를 위한 공공공간 조성, 단절된 이웃마을과의 소통과 통합 등 저소득층 거주지역 주민들의 삶의 질을 향상시키는데 기여하고 있음을 확인할 수 있었다. 공원의 창조적 재생은 저소득층 거주지역에 대한 관의 일방적 재개발정책이 아니라 마을 주민들의 참여를 유도함으로써 소속감과 장소 애착에 대한 동기를 유발하고 공공(도덕)의식을 확산하며 희망공간으로의 인식 전환을 이루는 계기를 마련하였다.