• Geotechnical Engineering
• /
• v.13 no.2
• /
• pp.101-124
• /
• 1997

Adjacent ground surface settlements by deep excavations are analyzed by field observations in the areas where excavations are performed in sandy soils or weathered soils underlain by rocks, First, the magnitude and the distribution of ground surface settlements, which are developed before main excavation activities (e. g., diaphragm wall installation and center pile installation) , are measured and analyzed. Secondly, the magnitude and the distribution of ground surface settlements by main excavation are measured and analyzed. And the results are compared with the predictions obtained by the empirical methods. Through case studies performed on the excavation sites where adjacent ground surfaces or structures are damaged by excavation activities, upper limit location of ground surface cracks are investigated.

• Journal of Korea Water Resources Association
• /
• v.30 no.6
• /
• pp.621-628
• /
• 1997

Excavation works on stream beds have been done for various reasons including aggregate collection, sediment dredging, bridge constructions, or laying pipes under the ground. These activities may cause significant loadings of SS (suspended solids) resulting in water pollution and other detrimental effects to the surrounding environment. This research investigates application potential of a fickian diffustion model, derived from two dimensional advection-diffusion equation through some simplifying assumptions, as a planning tool for the estimation of SS loadings from excavation works and evaluation fo pollution prevention measures in case that sophisticated numerical simulation models are not applicable due to various practical reasons. Through a case study of the Juncheon stream in the Donghae City on the Kangwondo Province, this study demonstrates applicability of the fickian diffustion model as a practical method for the preliminary estimation of Ss loadings from excavation works and evaluation of performance of fabrics made of synthetic fiber for the reduction of downstream SS concentration with deficient field data.

• Journal of the Korean GEO-environmental Society
• /
• v.13 no.10
• /
• pp.85-94
• /
• 2012

Recent development trend of construction projects in the urban area is the efficient use of insufficient land, however caused to difficult construction conditions because of many adjacent structures. This paper presents the case study that analyzed the ground settlement of railroad structure for the double track railway project of Gyeongui line, adjacent to the high rise building under ground excavating for substructure work, considering interaction of soft ground characteristics. Field survey and measurement works were carried out during construction of station and excavation of high rise building, and field data were analyzed to find the source of settlement of platform and railway. In addition, the soil reinforcement and foundation restoration were performed using in-situ injection method, i.e., D-ROG(Digitalized Restoring On Grout) method which filled the pore of bottom and around of foundation with micro-cement.

• Journal of the Korean GEO-environmental Society
• /
• v.11 no.2
• /
• pp.61-68
• /
• 2010

Recently, it is a trend of the underground excavation to become larger and deeper for more effective use of available space and with the advent of new excavation technologies. The ground typically has a complex stratigraphy. The excavation can lead to large deformation in the nearby structures and large earth pressure on the wall. This can lead to serious problem in the stability of the wall. For the retaining wall to be safely constructed, it is important that the stratigraphy and engineering properties of the ground be accurately estimated, based on the excavation plan and appropriate excavation method. This study uses the measured field data and numerical results to characterize the characteristics of the lateral deformation of the retaining wall. A touredof six field data were analysed. SUNEX, a numerical program which uses the elasto-plastic model to represent the soil, was used. It was shown that the measured deformations exceeded the proposed values for shallow excavations. Overall, the maximum lateral deformation was within the proposed value and hence, the walls were analyzed as safe.

• Journal of the Korea Construction Safety Engineering Association
• /
• v.1 no.1
• /
• pp.14-15
• /
• 1991

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.24 no.6
• /
• pp.599-615
• /
• 2022

In order to excavate underground tunnel most safely such as Han river, the slurry shield TBM method is applied to cope with face of high water pressure for many metro projects. In downtown subway project most of excavated soil is discharged externally whereas in road construction excavated soil is used as filling materials so it becomes important factor for success of the project. After excavated soil, weathered rock and soft rock are discharged with bentonite through discharge pipe to slurry treatment plant then those soils are separated in separation plant according to those size. Fine grained soil has been discarded together with filter cake but it is not toxic and can be mixed with coarse aggregate in proper ratio so this study is performed to find use of qualified filling material to meet quality standard. Therefore, in this study, legal standards and quality standards for the utilization of excavated soil of the slurry shield TBM method were examined and test was conducted to derive recycling way for filter cake and aggregate. And a plan for using it as a filling material for road construction was derived. Because bentonite is a clay composed of montmorillonite, and the excavated soil in the tunnel is also non-toxic, disposal of this material can waste social cost so it is expected to be helpful in the underground space development project that carries out the TBM project by recycling it as a valuable resource.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2006.04a
• /
• pp.259-262
• /
• 2006

본 연구는 지하처분연구시설(URT : Underground Research Tunnel)시설 건설공사와 관련하여 굴착 후의 지하수유동체계 변화를 예측하기 위하여 수행되었다. 지하수유동체계 모사를 위해 사용된 모델은 연속체 매질 개념의 Visual Modflow이며, URT 주변의 시추공에서 조사된 자료를 초기 입력자료로 이용하였다. 1단계 터널굴착 후에 계측된 지하수위 및 터널 내 지하수 유입량을 토대로 모델교정을 수행하였고, 교정된 모델을 이용하여 2단계 터널굴착 후의 지하수유동체계를 예측하였다. 1단계 굴착 후 약 4.3m의 수위강하가 발생한 KP-2번공은 2단계 굴착 후에는 약 0.05m의 수위강하가 예측되었다. 또한 2단계 굴착 후의 지하수위는 터널 입구를 기준으로 약 108m지점부터 터널 종점부 175m까지는 터널 상부에 분포하며, 종점부 175m지점에서는 지하수위가 터널 천장(roof)부로부터 약 12.7m 상부에 위치하는 것으로 예측되었다. 지하수위의 강하범위는 터널 중심부로부터 반경 약 300m까지 발생되는 것으로 예측되었고, 예상 지하수 유입량은 24.7ton/day로 1단계 공사 후보다. 약 2.7ton/day 증가하며, 공동굴착 전 터널 중심부의 지하수가 지표까지 도달하는 시간은 약 39.8년이 소요되는 것으로 나타났다.

• Journal of Korean Society of Disaster and Security
• /
• v.10 no.1
• /
• pp.43-46
• /
• 2017

Recently, the development of underground space is being actively carried out in the urban area by saturation, and the excavation works are mainly carried out by various excavation methods by the structures adjacent to the ground and underground excavation. During such excavation work, ground subsidence accidents are occurring due to inattention construction, lack of construction technology, and leakage of ground water. For the prevention of ground subsidence we studied the method of risk influence factors by soil investigation. Analysis of 75 sites soil investigation by U.S.C.S (Unified Soil Classification System), construction method, depth of excavation and we studied the risk influence factors with ground subsidence.

• Tunnel and Underground Space
• /
• v.27 no.6
• /
• pp.343-350
• /
• 2017

Amid increasingly saturated ground space, development of underground space has been booming throughout the world and excavation has been underway near the structure above or under the ground level. But the ground subsidence caused by improper or poor construction technologies, underground water leakage, sudden changes of stratum and the problem with earth retaining system component has been emerged as hot social issue. To deal with such problems nationwide, establishment of preventive and proactive disaster management and rapid restoration system has been pushed now. In this study, collection of the data on technology development trend to secure the underground safety was made, taking into account of internal change elements (changing groundwater level, damage to underground utilities, etc) and external change elements (vehicle load, earthquake and ground excavation, etc) during excavation. Amid the growing need of ground behavior analysis, ground subsidence evaluation technology, safe excavation to prevent ground subsidence and reinforcement technology, improvement of rapid restoration technology in preparation for ground subsidence and development of independent capability, this study is intended to introduce the technology development in a bid to prevent the ground subsidence during excavation. It's categorized into prediction/evaluation technology, complex detect technology, waterproof reinforcement technology, rapid restoration technology and excavation technology which, in part, has been in process now.

• Proceedings of the Korean Information Science Society Conference
• /
• 2007.06c
• /
• pp.149-152
• /
• 2007

최근 모든 분야에 대한 전산화가 가속화됨에 따라 업무 처리 능력의 향상과 함께 시간 비용의 절감을 이루고 있다. 이러한 추세와 함께 건설 분야에서의 전산화가 진행 중이다. 본 논문에서는 굴착장비의 전류 값과 굴착 깊이 계측을 통해 깊이에 따른 지반 강도를 전산화 시켜 추정함으로써 보다 합리적으로 말뚝 기초를 시공하는 방법 개발하고자 한다. 본 시스템은 건축, 토목, 건설 분야에서 국내 최초로 시도되는 것으로, 실제 공사 현장에서 획득되는 데이터의 분석을 도와 측정 오류(Human Error)를 최소화함은 물론 공사비 절감, 신속한 공사 정보 제공 등의 파급효과를 기대할 수 있다.