http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
고온 노출 시간에 따른 시멘트 페이스트 경화체의 푸리에 변환 적외분광 분석
김민혁 ( Kim Min-hyouck ),조현서 ( Cho Hyeon-seo ),이건철 ( Lee Gun-cheol ) 한국건축시공학회 2019 한국건축시공학회 학술발표대회 논문집 Vol.19 No.1
In this study, FT-IR analysis was performed by exposing cement paste to high temperature in order to characterize the change of hydration behavior of concrete structure damaged by fire accident. As the holding time increased, the Al-O vibration region increased due to the increase of Si-O symmetric Ca<sub>2</sub>(SiO<sub>4</sub>) and Brownilerite, and the OH stretching region tended to increase due to thermal decomposition of Ca(OH)<sub>2</sub>.
김민혁 ( Kim Min-hyouck ) 한국건축시공학회 2022 한국건축시공학회 학술발표대회 논문집 Vol.22 No.1
Blasting is a method that uses explosives to crush the ground. This method is a highly efficient ground cleaning method that can secure high efficiency in a short time. However, explosions can damage local properties and produce high noise and vibration. Therefore, it is important to be careful because there are disadvantages such as the occurrence of many complaints from the surrounding area. In this paper measured and analyzed the noise and vibration generated during blasting at the blasting site in Korea. The noise and vibration generated during blasting were measured by ES03303.2b and ES03402.2a at a distance of 6 m, 12 m from the blasting point. As a result of the measurement, there was little difference between small and medium scale except for precision vibration blasting at a distance of 6m, but noise difference according to blasting scale was evident at a distance of 12m. As a result of the measurement, the maximum noise level was reduced to 5.5 dB(A) and the vibration level was reduced to 7.7 dB(V). In the future, the reliability of the test results can be further improved through additional tests, and it is judged that noise and vibration prediction models based on blasting methods, amount of charge, measuring distance, etc. can be developed.
고온에 노출된 시멘트 페이스트의 화학적 안정화에 미치는 Damage Control Gas의 영향
김민혁(Kim, Min-Hyouck),허영선(Heo, Young-Sun),이건철(Lee, Gun-Cheol) 대한건축학회 2021 대한건축학회논문집 Vol.37 No.6
In this study, As a study on the recovery characteristics of concrete exposed to high temperature, the effect of DCG on the chemical recovery of cement paste exposed to high temperature was investigated. As the conditions for examination, the cracked surface was cured using a DCG to the cement paste test body heated to a high temperature of 800 ℃. Curing conditions was experimented with 20 minutes of DCG exposure, 40 minutes of retention. Experiments focused on chemical analysis using XRD and crack observation using high magnification cameras. Experiment result, Calcite appeared to increase in all sections, and Portlandite and C₃S were chemically combined with DCG to produce Calcite and reduced in all sections and the width of the crack could also be confirmed to be reduced in fine detail. In other words, in the case of DCG cured specimens, the amount of cracks after heating decreased compared to the non-cured specimens.
열적 피해를 입은 시멘트 페이스트 경화체의 유지시간에 따른 TGA 분석
김민혁 ( Kim Min-hyouck ),조현서 ( Cho Hyeon-seo ),지우람 ( Ji Woo-ram ),이건철 ( Lee Gun-cheol ),허영선 ( Heo Young-sun ) 한국구조물진단유지관리공학회 2019 한국구조물진단유지관리공학회 학술발표대회 논문집 Vol.23 No.1
In this study, to analyze the change of mass of concrete structure subjected to fire damage, cement paste was exposed at high temperature to maintenance time and analyzed mass change characteristics by TGA analysis. As a result of analysis, the mass reduction rate of cement paste decreased with increasing heating time after heating at high temperature.
CO<sub>2</sub> 가스 노출을 통한 고온 노출 시멘트 페이스트의 균열 회복 거동
김민혁 ( Kim Min-hyouck ),조현서 ( Cho Hyeon-seo ),이건철 ( Lee Gun-cheol ),허영선 ( Heo Young-sun ) 한국구조물진단유지관리공학회 2019 한국구조물진단유지관리공학회 학술발표대회 논문집 Vol.23 No.2
본 연구에서는 고온 가열된 시멘트 페이스트에 나타나는 균열을 CO<sub>2</sub> 가스 노출을 통한 회복 거동에 대해 관찰하였다. 시험체는 W/C 40 %의 시멘트 페이스트로 설정하였다. 전기가열로를 목표온도까지 도달시킨 후 가열로 상부에 부착하여 일면 가열을 실시한 후 가열된 면에 나타난 균열을 고배율 카메라로 촬영하였다. 촬영결과 CO<sub>2</sub> 가스 노출을 통한 회복 재령으로 인하여 시멘트 페이스트의 균열이 더 이상 진행되지 않은 것을 관찰하였다.
고온 환경에 노출된 시멘트 페이스트의 DCG 양생을 통한 화학적 안정화
김민혁 ( Kim Min-hyouck ),조현서 ( Cho Hyeon-seo ),이건철 ( Lee Gun-cheo ) 한국건축시공학회 2019 한국건축시공학회 학술발표대회 논문집 Vol.19 No.2
In order to examine the chemical stabilization through DCG curing of cement paste exposed to high temperature environment, we produced a sample of 40% W/C cement paste and heated it for 180 minutes under the heating temperature of 800 °C. The DCG curing time was 6, Three time conditions were divided into 12 and 18 hours. As a result of XRD analysis, Calcite (CaCO<sub>3</sub>) was found in Theta 29.4, 40, and 46.5o. As the curing time increased, the peak of Calcite also increased, which is due to the increased reaction time with DCG. Therefore, Calcite produced through DCG curing seems to have stabilized chemically by filling the pores generated by heating.
김민혁 ( Kim Min-hyouck ),이건철 ( Lee Gun-cheol ) 한국건축시공학회 2020 한국건축시공학회 학술발표대회 논문집 Vol.20 No.1
Concrete has a lower thermal conductivity or thermal diffusion coefficient compared to other building materials, so it is widely used as fireproof compartment material or refractory material for structures. However, in the event of thermal damage such as fire, cement curing agents and aggregates act differently, resulting in heat generation or deterioration of tissue due to dehydration, resulting in deterioration of physical properties and fire resistance. Therefore, in this study, the processing structure of cement paste is measured through nitrogen absorption method. The test specimen is a cement paste of 40% W/C and is set at 1000 °C under heating temperature conditions. As the temperature rose, the micro-pore mass below was reduced based on about 0.01 감소m, but the air gap above that was increased.Thus, in the range of pores measured in nitrogen adsorption, the air mass tended to decrease under high temperature conditions.