• Title/Summary/Keyword: lining system

Search Result 244, Processing Time 0.026 seconds

A study on drainage system of the room-and-pillar underground structure considering groundwater conditions (지하수 유출수 조건을 고려한 주방식 지하구조의 배수시스템 연구)

  • Lee, Chulho;Hyun, Younghwan;Hwang, Jedon;Chang, Soo-Ho
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.17 no.6
    • /
    • pp.675-683
    • /
    • 2015
  • The room-and-pillar construction method for underground space is adopted from the room-and-pillar mining method which is one of the most popular underground mining method in the world. Drainage system in the room-and-pillar underground construction method can be similar with the concept of single shell in tunnel because additional reinforcement except the TSL (thin spray-on liner) is not applied in the room-and-pillar construction method. That is, to decrease groundwater level and maintain safety in tunnel, the drainage pin hole inside lining (shotcrete) can be used. However, if total amount of outflow in the underground structure is relatively small or groundwater is not detected, such drainage system will not be useful and cause additional construction cost. In this study, outflow of conventional tunnels in South Korea was investigated and the criteria to determine whether the drainage pin hole is effective was suggested. And the guided drainage system was suggested when drainage pin hole was not applied in the room-and-pillar construction method.

Numerical analysis on the general requirement of permanently unsupported tunnels (영구 무지보 터널의 일반적인 조건에 관한 수치해석적 연구)

  • Yoon, Ji-Sun;Ryu, Ju-Yeol
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.5 no.2
    • /
    • pp.209-216
    • /
    • 2003
  • The present with in this country, rock bolt installation, shotcrete, and concrete lining in construction order has become accepted as a general tunnelling method in NATM. On the other hand Unlined tunnelling method, which was developed by many countries near Scandinavian Peninsula with hard rocks comparatively, has recently been introduced all over the world, and numerous studies about that have been being devoted to domestic tunnels. Unlined tunnelling method has been developed on the basis of the permanently unsupported openings, and general 7 requirements for them were suggested by Nick Barton. There are no case record about these conditions for Q-system in this country. Therefore, input parameters for Q-system under these conditions were applied to general road tunnel cross-section and numerical analyses for each condition were executed with UDEC-BB, Distinct Element Method.

  • PDF

Prevention of Soil Contamination from Underground Storage Facilities of Petroleum Product and Hazardous Chemical Compounds (유류 및 유해화학물질 저장시설에서의 토양오염 방지대책)

  • 배우근;홍종철;정진욱;김종호
    • Journal of Soil and Groundwater Environment
    • /
    • v.7 no.4
    • /
    • pp.40-47
    • /
    • 2002
  • The practices of the construction and management of the petroleum and hazardous chemical compound storage facilities in Korea were investigated extensively, and the problems were identified. The advanced technologies in the U.S.A were comparatively studied. Considering the effectiveness of leak prevention and applicability, the following measures were suggested. To prevent corrosion of a tank, a clad tank, an interior lining tank, or a double-wall tank were thought to be the most cost effective. For piping. use of non-metalic materials was suggested. A catchment basin seemed to be effective for preventing spills. For monitoring of leaks, constructions of more than one of detection systems, such as an automatic leak detection device. a vapor detection system, a groundwater monitoring system, or a double-wall monitoring system, were recommended.

Development of Liquid Fertilizer Spreading System for a Sloped Land (경사지용 가축분뇨 액비 살포장치 개발)

  • Oh, I.H.;Jang, C.H.;Kim, W.K.;Song, J.H.
    • Journal of Animal Environmental Science
    • /
    • v.16 no.2
    • /
    • pp.115-122
    • /
    • 2010
  • A major problem within the agricultural/farming community concerns the enormous amount of manure produced by livestock; one possible solution to this problem is to use the animal slurry as a liquid fertilizer. While there are several areas where this fertilizer could be used, one promising area of application is within chestnut tree fields. However, since most of these fields are located on slopes of varying grades and not on flat land, a different spread system is required. Generally, chemical fertilizer is spread in the chestnut field manually by hand; not only does this require a great deal of manpower it is also very difficult and hard work. In our lab experiment, we investigated the relationship between the amount of fertilizer spread and the length of pipe used at varying pressure levels. The hose in our system utilized PVC piping with evenly spaced holes for the fertilizer to dissipate. We initially found that the amount of spread was greatly reduced by reducing pipe pressure. While the difference of the amount of spread during fertilizing was not great, we did find that the reduction of the spread could be correlated to the frictional resistance of the inner lining of the pipe. Based on this, we hypothesized that an increase in pipe pressure would yield a consistent spread. Additionally, a similar outcome could be obtained by regulating the distance of the holes in the pipe and their diameter.

Nursing Interventions of the Lupus Patient (루푸스(Lupus) 환자의 간호중재)

  • Kim, Myung-Ja;Sohng, Kyeong-Yae
    • Journal of muscle and joint health
    • /
    • v.2 no.2
    • /
    • pp.197-208
    • /
    • 1995
  • The purpose of this study is to describe specific system manifestations and suggested nursing interventions in patients with lupus. Lupus is a chronic, inflammatory, multisystemic disorder of the immune system. Antibodies are formed which react against the person's own normal tissue. This abnormal response can be very damaging and leads to the many manifestations of the lupus. Lupus can affect any part of the body, and patients experience symptoms in organs involved. So lupus patients have integumentary, blood, central nervous system, eye, gastrointestinal, musculoskeletal, kidney, heart and lining membranes, reproductive system involvement. The courses are unpredictable and very individualized. Lupus varies greatly in severity from mild cases requiring minimal interventions to those in which significant damage occurs to vital organs such as the lungs, heart, kidney and brain which ultimately can be fatal. In addition to direct physical care, the nursing professional has an excellent position from which to support the lupus patient. Patients need assistance with receiving current, accurate information about the disease process and also to be helped in developing realistic expectations and goals. Nursing interventions for the patient with lupus is challenge drawing on at the resources, knowledge and strengths the nursing teams have to offer. Because of the unpredictable, highly individualized and frequently changing the nature of the disease itself as well as the intricacy of the patient's needs. The nurse has a key role in its management. The patient and nurse, working together, have much to offer each other. These are of inestimable value to the patient. As the nurse listens to the patient and learns what problems the patient perceives, can guide the patient in a self-help program that allows to adapt to living with a chronic illness.

  • PDF

Deep learning based crack detection from tunnel cement concrete lining (딥러닝 기반 터널 콘크리트 라이닝 균열 탐지)

  • Bae, Soohyeon;Ham, Sangwoo;Lee, Impyeong;Lee, Gyu-Phil;Kim, Donggyou
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.24 no.6
    • /
    • pp.583-598
    • /
    • 2022
  • As human-based tunnel inspections are affected by the subjective judgment of the inspector, making continuous history management difficult. There is a lot of deep learning-based automatic crack detection research recently. However, the large public crack datasets used in most studies differ significantly from those in tunnels. Also, additional work is required to build sophisticated crack labels in current tunnel evaluation. Therefore, we present a method to improve crack detection performance by inputting existing datasets into a deep learning model. We evaluate and compare the performance of deep learning models trained by combining existing tunnel datasets, high-quality tunnel datasets, and public crack datasets. As a result, DeepLabv3+ with Cross-Entropy loss function performed best when trained on both public datasets, patchwise classification, and oversampled tunnel datasets. In the future, we expect to contribute to establishing a plan to efficiently utilize the tunnel image acquisition system's data for deep learning model learning.

Case study on design and construction for cross-connection tunnel using large steel pipe thrust method in soil twin shield tunnels underneath airport (공항하부 토사 병설 쉴드터널에서 대구경 강관추진에 의한 횡갱 설계/시공사례 연구)

  • Ahn, Chang-Yoon;Park, Duhee
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.23 no.5
    • /
    • pp.325-337
    • /
    • 2021
  • On the road and rail tunnels, the evacuation pathway and facilities such as smoke-control and fire suppression system are essential in tunnel fire. In the long twin tunnels, the cross-connection tunnel is usually designed to evacuate from the tunnel where the fire broke out to the other tunnel. In twin shield tunnels, the segment lining has to be demolished to construct the cross-connection tunnel. Considering the modern shield TBM is mostly the closed chamber type, the exposure of underground soil induced by removal of steel segment lining is the most danger construction step in the shield tunnel construction. This case study introduces the excavation method using the thrust of large steel pipe and reviews the measured data after the construction. The large steel pipe thrust method for the cross-connection tunnel can stabilize the excavated face with the two mechanisms. Firstly, the soil in front of excavated face is cylindrically pre-supported by the large steel pipe. Secondly, the excavated face is supported by the plugging effect caused by the soil pressed into the steel pipe. It was reviewed that the large steel pipe thrust method in the cross-connection tunnel is enough to secure the construct ability and stability in soil from the measurement results about the deformation and stress of steel pipe.

Development of adjuvant for effective oral vaccine application (경구백신의 효율적인 적용을 위한 면역 보조제 개발)

  • Kim, Sae-Hae;Seo, Ki-Weon;Kim, Ju;Jang, Yong-Suk
    • Journal of Plant Biotechnology
    • /
    • v.37 no.3
    • /
    • pp.283-291
    • /
    • 2010
  • Vaccine is one of the best known and most successful applications of immunological theory to human health and it protects human life through inducing the immune response in systemic compartment. However, when we consider the fact that mucosal epithelium is exposed to diverse foreign materials including viruses, bacteria, and food antigens and protects body from entry of unwanted materials using layer of tightly joined epithelial cells, establishing the immunological barrier on the lining of mucosal surfaces is believed to be an effective strategy to protect body from unwanted antigens. Unfortunately, however, oral mucosal site, which is considered as the best target to induce mucosal immune response due to application convenience, is prone to induce immune tolerance rather than immune stimulation. Since intestinal epithelium is tightly organized, a prerequisite for successful mucosal vaccination is delivery of antigen to mucosal immune induction site including a complex system of highly specialized cells such as M cells. Consequently, development of efficient mucosal adjuvant capable of introducing antigens to mucosal immune induction site and overcome oral tolerance is an important subject in oral vaccine development. In this review, various approaches on the development of oral mucosal adjuvants being suggested for effective oral mucosal immune induction.

Microbiome-Linked Crosstalk in the Gastrointestinal Exposome towards Host Health and Disease

  • Moon, Yuseok
    • Pediatric Gastroenterology, Hepatology & Nutrition
    • /
    • v.19 no.4
    • /
    • pp.221-228
    • /
    • 2016
  • The gastrointestinal exposome represents the integration of all xenobiotic components and host-derived endogenous components affecting the host health, disease progression and ultimately clinical outcomes during the lifespan. The human gut microbiome as a dynamic exposome of commensalism continuously interacts with other exogenous exposome as well as host sentineling components including the immune and neuroendocrine circuit. The composition and diversity of the microbiome are established on the basis of the luminal environment (physical, chemical and biological exposome) and host surveillance at each part of the gastrointestinal lining. Whereas the chemical exposome derived from nutrients and other xenobiotics can influence the dynamics of microbiome community (the stability, diversity, or resilience), the microbiomes reciprocally alter the bioavailability and activities of the chemical exposome in the mucosa. In particular, xenobiotic metabolites by the gut microbial enzymes can be either beneficial or detrimental to the host health although xenobiotics can alter the composition and diversity of the gut microbiome. The integration of the mucosal crosstalk in the exposome determines the fate of microbiome community and host response to the etiologic factors of disease. Therefore, the network between microbiome and other mucosal exposome would provide new insights into the clinical intervention against the mucosal or systemic disorders via regulation of the gut-associated immunological, metabolic, or neuroendocrine system.

A Case Study on Damage of The Tunnel Lining by Mine Waste Water (긴급제언 - 광산폐수에 의한 터널라이닝 손상사례 연구)

  • Lee, Yu-Seok;Oh, Young-Seok
    • Journal of the Korean Professional Engineers Association
    • /
    • v.45 no.4
    • /
    • pp.47-56
    • /
    • 2012
  • According to the policy of coal industry promotion, a lot of mines were abandoned. As the abandoned mines were neglected, environmental pollution such as settlement of ground, ground-water run-off, landscape damage etc were accompanied around abandoned mines. The government was promoting countermeasures of environmental contamination but most of the Countermeasures were aimed at protecting the ecological system not infrastructure. For this reason, abandoned mines impact on infrastructure has been relatively neglected. Most mines are located in mountainous so there is a tunnel among typical infrastructure around abandoned mines. In this paper, the effect of Mine drainage, Typical pollution source of abandoned mine, was introduced into the using tunnel focusing on the types and examples.

  • PDF