This study aims to evaluate thermal performance using the ASTR method. Its findings are as follows: 1) The measured U-Values of 49A type and 59A type walls were almost the same as the theoretically calculated values. 2) One notable phenomenon for both walls was that the interior surface temperatures of the channels attached to corners were up to 10.4% lower than that of the cross of the wall, even though they consisted of the same materials. This is due to the surface temperature drop caused by the thermal bridge. 3) The surface temperatures of the thermal bridge were converted into U-Values. The U-Value of the top left corner on the 59A type house was 1.044W/m²K, and of the bottom right corner on the 49A type house was 0.959W/m²K. Therefore, the thermal performance of the thermal bridge area was decreased after construction. 4) Differences were found in the results of comparing heat transfer analysis simulation data and measured data. A maximum difference of 12.4% occurred in the top left corner on 59A type, and of 7.6% occurred in the bottom right corner on 49A type. 5) The results of a heat transfer analysis simulation showed that the temperature of both 49A type and 59A type top right corner were the lowest, but in-situ measurement results were the lowest in the bottom right corner on 49A type and in the top left corner on 59A type. These results are considered to be due to the occurrence of thermal bridges and a deterioration in the construction quality.
In this study examined the strength of wall concrete using insulated molds and non-insulated forms by monitoring the strength of the structure using a wireless sensor network by maturity method. It was confirmed that the temperature and compressive strength of the structures are monitored in real time, along with effective strength control.
본 연구에서는 저온환경에서 콘크리트 동해를 방지하기 위해 생석회의 화학반응을 활용한 발열시트 및 단열재를 사용하여 제작한 거푸집 특성을 실험을 통해 평가하였다. -10°C 정온조건에서 거푸집 실험 결과, 발열시트가 부착된 거푸집의 경우 발열시트 내부 생석회의 발 열로 인해 타설 초기에 일반거푸집에 비해 10°C이상 높은 온도이력을 보여주었고 단열재를 부착한 거푸집의 경우 콘크리트 수화열을 보존하 여 지속적으로 높은 온도를 유지하는 특징을 나타냈다. 아이소핑크와 발열시트를 부착한 거푸집과 진공단열재를 붙인 거푸집이 압축강도나 적산온도에서 가장 높은 값을 가졌다. 압축강도 측정시 진공단열재 및 아이소핑크와 발열시트를 부착한 거푸집이 재령 3일에서 약 5 MPa로 가 장 높게 측정되었다. 몽골 현지 외기온도에서도 실험을 하였는데 앞선 결과와 마찬가지로 발열시트, 단열재를 함께 붙인 거푸집이 48시간 동안 25°C 이상으로 가장 높은 온도이력를 나타내었다. 따라서 거푸집에 발열시트 및 단열재 부착을 함으로써 발열 및 단열효과로 인해 저온환경에 서 콘크리트 강도발현에 도움을 주는 것을 확인할 수 있었다.
In this study, the heat insulating performance increase the indoor temperature of the building is applied to the concrete was compared with plain concrete. As a result, the indoor surface at the outside temperature of 4.69∼7.32 ℃ temperature conditions showed a difference of up to 1.10 ℃, the lowest 0.54 ℃, indoor temperature is up to 0.95 ℃, 0.63 ℃ lower results showed a minimum.
The purpose of this study is to investigate correation between semi-adiabatic temperature and adiabatic temperature rise of ordinary portland cement(OPC) and ternary blended cement(TBC). And concrete adiabatic temperature rise factor was estimated by semi-hydration heat analysis test.
In this study, the heat insulating performance increase the indoor temperature of the building is applied to the concrete was compared with plain concrete. As a result, the indoor surface at the outside temperature of 10.4 ~ 22.4 ℃ temperature conditions showed a difference of up to 0.6 ℃, the lowest 0.6 ℃, indoor temperature is up to 0.2 ℃, 0.2 ℃ lower results showed a minimum.
Experimental program was conducted for hydration heat evaluation of concrete using strontium based phase change material (PCM). Adiabatic temperature rise test was investigated for four days. In results, concrete with strontium based PCM has about 20 percent lower hydration heat than ordinary one.
In this study, we intended to estimate the heat of hydration of carbon nanotubes-cement composites. It was tried to present the basic data of the heat of hydration characteristics of the CNT-reinforced cement composite by the simple adiabatic temperature rise test. The results indicated that adding CNT reduced the heat of hydration of cement composites.
This research is to measure and analyze the thermal performance of the apartment structure and to evaluate and establish standards of thermal insulation defect in order to make the basic data necessary for determining the degree of the thermal performance degradation and for repairing and reinforcing the exterior wall of the existing apartment. Furthermore, it is to predict the part of occurrence of the thermal bridge and condensation at the apartment building structure. On the other one hand, it is also to analyze the degree of thermal insulation performance according to the standards of thermal insulation and elapsed time, through the analysis by the workability of concrete.