PURPOSES : This study aims at evaluating the use of an electromagnetic density gauge (EDG) to measure the in situ density and air-void content of asphalt concrete (AC) pavement.
METHODS : In situ AC pavement density and air-void readings were obtained from two sites (Daegu and Ulsan) using an EDG. Calibration of the EDG was conducted by first obtaining density values at three different positions, on each pavement where core samples were extracted afterward. The core samples were then tested to obtain laboratory density and air-void values. The density measured using the EDG was then subtracted from the laboratory values to obtain the offset calibration values, which were then adopted to calibrate the in situ measurements using the EDG. Moreover, to analyze the effect of moisture on the pavement surface, EDG measurements were conducted under dry and wet conditions to compare the in-situ readings.
RESULTS : The in-situ density readings of AC tend to be higher in moist/wet conditions. By applying the calibration value to the EDG readings, the density error percentage was reduced from 0.61% to 0.096%, and 0.64% to 0.16% for Daegu and Ulsan sites, respectively. Consequently, the air-void content error percentage was reduced from 12.8% to 1.04%, and from 10.07% to 1.78% for Daegu and Ulsan sites, respectively.
CONCLUSIONS : The electromagnetic density gauge (EDG) is an effective tool for the non-destructive measurement of in situ pavement density. By applying offset calibration values, the error in the field readings was reduced, and the accuracy of the EDG measurements was improved.

ABSTRACT
1. Introductuon
    1.1. Literature review
    1.2. Research contents
2. Pavement density measurement usingelectromagnetic density gauge
    2.1. Electromagnetic density gauge operationprinciple
    2.2. Electromagnetic density gauge measurementprocedure
3. In-situ density measurement and coresample extraction
    3.1. In-situ density measurement
    3.2. Effect of moisture condition and core sampleextraction
4. Results-discussion
    4.1. In-situ density measurement
    4.2. Effect of moisture condition
    4.3. Offset calibration value and its applicationon raw in-situ density measurement data
5. Conclusions
Acknowledgement
REFERENCES

• Maulana Reynalda(Dept. of Civil Engineering · Kunsan National Univ. · Research Assistant) | 마울라나 레이날다
• Aplicano, Bruce(Dept. of Civil Engineering · Kunsan National Univ. · Research Assistant) | 브루스 아플리카노
• Lee, Hyun-Jong(Member · Dept. of Civil & Environmental Engineering · Sejong University · Professor) | 이현종
• Park, Dae-Wook(Member · Dept. of Civil Engineering · Kunsan National University · Professor) | 박대욱 Corresponding author