Regression analysis of the correlation between ultrasonic pulse velocity and strength to examine the demoulding time of non-sintered hwangto concrete

비소성 황토 콘크리트의 거푸집 탈형 시점 검토를 위한 초음파속도와 강도의 상관관계 회귀 분석

Recently, interest in reducing cement has been growing. Hwangto, an eco-friendly material, has advantages such as air purification effect and humidity control, but when used, accidents such as form collapse may occur due to low strength and reduced durability. In order to quantitatively evaluate the timing of mold demolding, we would like to evaluate the timing of mold demolding through correlation with compressive strength using ultrasonic pulse velocity. As a result, the time at which 5 MPa is developed is after 20 hours for the test specimen of W/B 41 , in the case of W/B 33, NC33 and HTC33-15 were equally expressed at 12 hours, and HTC33-30 was expressed at 16 hours.