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An Experimental Study on Characteristics of Averaged Electromagnetic Properties considering Moisture Changes in Cement Mortar

시멘트 모르타르의 수분변화에 따른 평균화된 전자기 특성에 대한 실험적 연구

  • Kwon, Seung-Jun (Dept. of Civil and Environmental Engineering, University of California Irvine) ;
  • Maria, Q. Feng (Dept. of Civil and Environmental Engineering, University of California Irvine) ;
  • Na, Ung-Jin (Busan Port Construction Office, Ministry of Land, Transport and Maritime affairs)
  • Published : 2009.04.30

Abstract

Many researches on electromagnetic (EM) properties like dielectric constant and conductivity are performed since they can be characterized in nonmetallic cement-based material such as mortar and concrete. However, they are much affected by the moisture so that the behaviors of EM properties are to be clearly understood. In this paper, measurements for saturation and EM properties are performed for cement mortar specimens with five different water to cement (W/C) ratios including basic tests like compressive strength and porosity measurement. Every saturated specimens are exposed to room condition and the changes in EM properties caused by decreasing saturation are analyzed. In the saturated condition, higher measurement of EM properties are evaluated in the specimens with higher porosity, however this relationship is adversely changed with drying process. Since the pores without filled water causes the decreases in EM properties, the measurements show stable and linear increment with the lower W/C ratios. Furthermore, the increasing ratios of EM measurements with W/C ratio are shown with saturation and the relationships between them are derived through regression analysis.

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