• 한국습지학회지
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• 제26권2호
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• pp.139-146
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• 2024

노후된 관거 및 지하구조물의 균열 보수에 아스팔트계 주입재, 우레탄계 주입재, 시멘트계 주입재, 아크릴계 주입재 등 다양한 주입재가 사용되고 있다. 친환경적이고 습윤상태에서 경화가 잘되고 온도변화에 안정적인 물성을 갖는 아크릴계 누수 보수재에 대하여 연구하였다. 개량된 아크릴 누수 보수재와 기존 아크릴레이트 주입재의 성능 비교를 위하여 KS 규격의 실험방법에 준용하여 수중침지 길이변화율 시험, 수중 유실 저항성 시험, 내화학 성능시험을 실시하였다. 비교 실험해 본 결과 개량된 아크릴 누수 보수재는 기존 아크릴레이트 주입재보다 습윤상태, 온도변화, 화학적 반응에 따른 수축변화가 없었고 수중 저항성 실험에서 유실되지 않았다. 또한, 개량된 아크릴 누수 보수재의 환경적 영향성을 알아보기 위해 어류급성독성 실험과 급성경구독성 실험을 진행하여 관찰해 본 결과 실험체의 사망률이 없었고 특별한 유의점이 발견되지 않았다. 본 연구의 실험결과 개량된 아크릴 누수 보수재가 성능적으로 우수하고 환경적으로 안전하고 인체에 무해하다고 판단되었다. 본 연구의 다양한 실험결과 기존의 아크릴레이트 보수재보다 개량된 아크릴 누수 보수재가 관거 및 지하구조물 균열 부위의 보수재로 사용되기 적합하다고 사료된다. 본 연구는 아크릴 누수 보수재에 대한 적용성 평가에 대한 연구로 향후 기술 개발에 활용자료로 제안하고자 한다.

• 한국소음진동공학회논문집
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• 제14권2호
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• pp.95-104
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• 2004

Leaks in underground pipelines can cause social, environmental and economical problems. One of relevant countermeasures against leaks is to find and repair of leak points of the pipes. Leak noise is a good source to identify the location of leak points of the pipelines. Although there have been several methods to detect the leak location with leak noise, such as listening rods, hydrophones or ground microphones, they have not been so efficient tools. In this paper, accelermeters aroused to detect leak locations which could provide an easier and more efficient method. Filtering, signal processing and algorithm of raw input data from sensors for the detection of leak location are described. A 120m-long and a 70m-long experimental pipeline systems are installed and the results with the systems show that the algorithm with the accelerometers offers accurate pinpointing for leaks location detection. Theoretical analysis of sound wave propagation speed of water in underground pipes, which is critically important in leak locating, is also described.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 춘계학술대회논문집
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• pp.821-826
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• 2003

Leaks in underground pipelines can cause social, environmental and economical problems. One of a good contermeasures of leaks Is to find and repair of leak points of pipes. Leak noise is a good source to identify the location of leak points of pipelines. Although there have been several methods to detect the leak location with leak noise, such as listening rods, hydrophones or ground microphones, they were not so efficient tools beca. In this paper, two accelermeters are used to detect leak locations which could provide an easier and efficient method. The filtering, signal processing and algorithm is described for the detection of leak location. A 120m-long pipeline system for experiment is installed and the results with the system show that the algorithm with the two accelerometers gives very accurate pinpointing of leaks. Theoretical analysis of sound wave propagation speed in underground pipes is also described.

• Corrosion Science and Technology
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• 제3권6호
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• pp.233-239
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• 2004

Primary water stress corrosion cracking of steam generator tubings occur on many tubes in pressurized water reactors(PWRs), and they are repaired using sleeves or plugs. In order to develop proper repair criteria, it is necessary to know the leak behavior of the tubes, which have stress corrosion cracks. Crack development tests were carried out on the tubes at room temperature, and leak rate and burst pressure were measured on the degraded tubes at room temperature and a high temperature. No leakage was detected on the tubes where 100 % through wall crack developed, at 1560 psi, which is an operating pressure difference of pressurized water reactors(PWRs). In some tests, leak rates of the tubes increased with time at a constant internal water pressure. A test tube showed a very small amount of leakage at 2700 psi in a high temperature pressure test at $282^{\circ}C$, but it disappeared after the pressure increased slightly. Even cracks are 100 % through wall, they need to open in order to reach a certain amount of leak rate at the operating pressure difference.

• 상하수도학회지
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• 제19권1호
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• pp.8-15
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• 2005

Field measurement data on water leakage are not readily available and it causes inaccurate assessment of water demand and poor supply planning. In this study, the procedure for leakage detection and unaccounted water calculation is proposed and applied to a city. The city has suffered from the significant amount of leak water and the financial loss as a result. Measurements were made for pressure and flow at 18 locations before and after the repair. Repair of the leakage increased pressure up to $2.0kgf/cm^2$ and saved 17.1% of water supply from distribution reservoirs. Monetary value of annual water savings for the entire city amounts to 1 billion won. It is believed that leakage detection and data analysis conducted in this study will contribute to the change of current practice and to the establishment of better water supply management system.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2019년도 추계 학술논문 발표대회
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• pp.241-242
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• 2019

This technology is a water leak repair technology using composite materials of concrete structures that block leakage of structures by injecting rapid microcement into the face of underground concrete to block water and injecting flexible glycidylacrylate. Rapid micro cement system repair materials are mixed with fine fibers to improve the flexural sensitivity of the material and to form a layer that blocks stabilized water at the back of the structure by allowing rapid and tight spatial filling during injection with high cohesion The glycidylacrylate repair material can control the expansion rate, and the external stress also has the characteristic that the form of the material is not destroyed or separated, which can also be applied to vibrating induced structures that produce repetitive fatigue loads, and has an effective durability in saline, alkali, acid (chloric acid, sulfuric acid, nitric acid).

• Corrosion Science and Technology
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• 제8권5호
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• pp.188-192
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• 2009

A forced outage due to a steam generator tube leak in a Korean nuclear power plant was reported.1) Primary water stress corrosion cracking has occurred in many tubes in the plant, and they were repaired using sleeves or plugs. In order to develop proper repair criteria, it is necessary to understand the leak behavior of the tubes containing stress corrosion cracks. Stress corrosion cracks were developed in 0.1 M sodium tetrathionate solution at room temperature. Steam generator(SG) tubes with short cracks were successfully fabricated with a restricted solution contact method. The leak rates of the degraded tubes were measured at room temperature. Some tubes with 100 % through wall cracks showed an increase of leak rate with time at a constant pressure.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 춘계 학술논문 발표대회
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• pp.156-157
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• 2014

PC apartment house 15 years have elapsed have various deteriorations by water leakage in roof and wall. The prior investigation such as investigating of leakage repair history of PC apartment and the field investigation were carried out to solve the water leak problem in its structure. The path of water was analyzed on the parts of greatest water leak such as roof parapet, roof floor, side wall, corridor and balcony. As a result, the specific path of the water leakage was identified in various structure units.

• Corrosion Science and Technology
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• 제3권1호
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• pp.30-33
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• 2004

It has been reported that some events of a rupture of seam generator tube have occurred in nuclear power plants around the world. Main causes of the leakage are from various types of corrosion in the steam generator(SG) tubings. Primary water stress corrosion cracking(PWSCC) of steam generator tubings have occurred in many tubes in Korean plant, and they were repaired using sleeves or plugs, In order to develop proper repair criteria, it is necessary to ascertain the leak behavior of the tubings. A high pressure leak and burst testing system was manufactured. Various types of Electro Discharged Machined (EDM) notches were developed on the SG tubes. Leak rate and burst pressure were measured on the tubes at room temperature. Burst pressure of the part through wall defected tubes depends on the defect depth, Water flow rates after the burst were independent of the t1aw types; tubes having 20 to 60 mm long EDM notches showed similar flow rates regardless of the defect depth. A fast pressurization rate gave the tube a lower burst pressure than the case of a slow pressurization.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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• pp.142-143
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• 2017

An analysis of the current water leak status of understand structure (underground parking lots, staircases, plumbing systems, water reservoirs, etc.) of multi-family housing in South Korea shows that water leaks are found from cracks in all areas of the underground structure caused by the degradation environment (water pressure by underground water, humidity, temperature, earth pressure, soil behaviour and vibration, etc.), which result in various problems, including mold, malodour, debonding of finishing materials, exfoliation, breakout, water leaks in electrical boxes, efflorescence, sedimentation of calcium hydroxide, decoloration, rusting, damages and pollution among others. Therefore, this study aims to analyse the current status of water leaks in underground structure and use the results as the basic data for developing a standard guideline for water leaks and maintenance by parts of the underground structure of multi-family housing.