# 실측에 의한 강박스거더교의 상하 온도차에 대한 연구

• Lee, Seong-Haeng (Department of Civil Engineering, Pusan National University) ;
• Park, Young-Chun (Department of Ulsan-Pohang Line PM, Korea Rail Network Authority)
• 이성행 (부산대학교 토목공학과) ;
• 박영춘 (한국철도시설공단 영남본부 울산포항PM부)
• Accepted : 2018.08.03
• Published : 2018.08.31
• 46 5

#### Abstract

For domestic application of the temperature gradient model proposed by foreign design standards, a specimen of steel box girder bridge was fabricated with the following dimensions: 2.0 m width, 2.0 m height and 3.0 m length. Temperature was measured using 24 temperature gauges during the summer of 2016. The reliability of the measured data was verified by comparing the measured air temperature with the ambient air temperature of the Korea Meteorological Administration. Of the measured gauges, four temperature gauges that can be compared with the temperature difference of the Euro code were selected and used to analyze the distribution of the measured temperatures at each point. The reference atmospheric temperature for the selection of the maximum temperature difference was determined by considering the standard error. Maximum and minimum temperatures were calculated from the four selected points and the resulting temperature difference was calculated. The model for the temperature difference in the steel box girder bridge was shown by graphing the temperature difference. Compared to the temperature distribution of the Euro code, the presented temperature difference model showed a temperature difference of $0.9^{\circ}C$ at the top and of $0.3^{\circ}$ to $0.4^{\circ}C$ at the intermediate part. These results suggested that the presented model could be considered relatively similar to the Euro code The calculated standard error coefficient was 2.71 to 2.84 times the standard error and represents a range of values. The proposed temperature difference model may be used to generate basic data for calculating the temperature difference in temperature load design.

#### Keywords

Temperature difference;Steel box girder specimen;Temperature measurement;Euro code;Temperaturegradient model

#### Acknowledgement

Supported by : 한국연구재단

#### References

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