• Title/Summary/Keyword: cold Weather

Search Result 520, Processing Time 0.025 seconds

A Study on Cold-Weather Curing Quality Management Based on Using Energy Saving Electronic Heater (에너지 절감형 전기히터를 활용한 동절기 양생품질 관리방안)

  • Jo, Man-Ki;Hong, Sung-Min;Park, Jong-Hun;Kim, Jin-Sik;Lee, Dong-Hyun;Cho, Seong-Jun
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2020.11a
    • /
    • pp.109-110
    • /
    • 2020
  • In This study, we tried to review an efficient curing method in consideration of safety and constructability among the problems of winter construction. In other words, as a result of the mock-up test, the measured value of carbon monoxide was 0 ppm in the case of an electric hot air fan. Since there is no carbon monoxide, problems such as suffocation are expected to be solved. In terms of temperature characteristics, electric hot air fans exhibited high thermal efficiency performance with a slight difference in upper/lower temperatures compared to the existing ones. In the future, we plan to conduct thermal efficiency evaluation through actual site performance verification. We will propose an efficient curing method through applicability evaluation.

  • PDF

Diagnose of Impaired Depth due to Early Frost Damage of the Concrete Using Organic Pigment Concentration (유기안료 농도를 이용한 동절기 초기동해 피해 콘크리트의 깊이 진단)

  • Choi, Yoon-Ho;Lim, Gun-Su;Kim, Sang-Min;Kim, Jong;Han, Min-Cheol;Han, Cheon-Goo
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2020.06a
    • /
    • pp.167-168
    • /
    • 2020
  • In this study, we attempted to present a method for diagnosing the depth of the early frost damage concrete using organic pigments under the cold weather. As a result, it is considered that the organic pigment did not penetrate into the voids of the concrete that had been damaged by the early frost damage and only the surface was adhered. Therefore, when fine particles that can be melted in water and pass through voids are used, it is analyzed that it can penetrate damaged part of the concrete.

  • PDF

Performance Verification of Curing Method in Cold-Weather with Using Energy Saving Electronic Heater for achieving Korean Carbon Neutra (탄소중립 확보를 위한 친환경 동절기 대체 열원 성능 검증)

  • Jo, Man-Ki;Kim, Sang-Kyun;Hong, Seong-Min;Park, Jong-Hun
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2021.11a
    • /
    • pp.192-193
    • /
    • 2021
  • Recently, the need to strengthen the Air Environment Conservation Act and secure alternative heat sources during the winter by carbon neutrality policies has been raised. Accordingly, winter construction, which has safety and quality measures, is emerging as an essential factor. It is believed that eco-friendly tropical type electric hot air heaters will be able to solve most of the problems of winter construction at construction sites, especially prevention of suffocation and fire accidents. In addition, as a result of on-site performance verification, it has secured more than the same performance as the existing curing method, and the curing technology can create an eco-friendly and pleasant working environment while considering safety and construction.

  • PDF

Temperature History of Slab Concrete Depending on Insulation Curing Method in Cold Weather Concreting (한중시공시 단열양생방법 변화에 따른 슬래브 콘크리트의 온도이력 특성)

  • Kim Jong-Back;Lim Choon-Goun;Park Koo-Byoung;Kim Seoung-Soo;Han Cheon-Goo
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2005.05a
    • /
    • pp.17-20
    • /
    • 2005
  • This paper reported the temperature history of concrete placed at deck plate slab under cold climate condition by varying with surface insulating type. No curing sheet and simple insulation curing including non-woven fabric, double layer bubble sheet, the combination of double layer bubble sheet and non-woven fabric dropped temperature below zero within 24 hours, which caused frost damage at early age. On the other hand, the combination of double layer bubble sheet and non-woven fabric and double layer bubble sheet and styrofoam maintained minimum temperature above $4^{\circ}C\;and\;8^{\circ}C$, respectively. Based on core test results compressive strength of concrete with the combination of double layer bubble sheet and non-woven fabric and double layer bubble sheet and styrofoam was higher than those with other curing method due to good insulation effect.

  • PDF

Clustering of extreme winds in the mixed climate of South Africa

  • Kruger, A.C.;Goliger, A.M.;Retief, J.V.;Sekele, S.S.
    • Wind and Structures
    • /
    • v.15 no.2
    • /
    • pp.87-109
    • /
    • 2012
  • A substantial part of South Africa is subject to more than one strong wind source. The effect of that on extreme winds is that higher quantiles are usually estimated with a mixed strong wind climate estimation method, compared to the traditional Gumbel approach based on a single population. The differences in the estimated quantiles between the two methods depend on the values of the Gumbel distribution parameters for the different strong wind mechanisms involved. Cluster analysis of the distribution parameters provides a characterization of the effect of the relative differences in their values, and therefore the dominance of the different strong wind mechanisms. For gusts, cold fronts tend to dominate over the coastal and high-lying areas, while other mechanisms, especially thunderstorms, are dominant over the lower-lying areas in the interior. For the hourly mean wind speeds cold fronts are dominant in the south-west, south and east of the country. On the West Coast the ridging of the Atlantic Ocean high-pressure system dominate in the south, while the presence of a deep trough or coastal low pressure system is the main strong wind mechanism in the north. In the central interior cold fronts tend to share their influence almost equally with other synoptic-scale mechanisms.

A Study on Concrete Material Quality Management Based on Various Test of Construction Condition under Hot Weather Circumstance (서중(暑中) 환경에서 현장 콘크리트 시험을 통한 재료 품질관리 방안)

  • Park, Shin
    • Journal of the Korea Institute of Building Construction
    • /
    • v.5 no.3 s.17
    • /
    • pp.91-99
    • /
    • 2005
  • It is required to study systematical on the concrete quality management to extend structure life because rebuilding effect is reducing under present condition of large sized and high stories structure. Concrete, which shows its intensity by hydrating action and a big change in quality according to hot weather and temperature, produces a lot of qualify problem under hot and cold weather Because of each specification and construction plan which does not have basic standard on site, concrete's quality is irregular and makes some defect. As a result, Daegu is turned out to be the longest area after investigating application period and days focused on 8 cities weather information about relationship between hot weather circumstance and construction environment. Therefore, we first surveyed the concrete material in the region and found out the problem of quality nanagement. Then figure out the way of solution. Moreover, we integrated concrete material quality management, which is applied differently to each site, to have equal quality and to reduce defect from construction site. And then, based on various test of construction condition and analysis of quality management item, we suggest effective concrete quality management to make concrete material construction standard guide and plan under hot weather.