MEASUREMENT OFARITHMETICAL MEAN ROUGHNESS OF CONCRETE BY TRANSCEIVERTYPE AERIAL ULTRASONIC SENSOR

Abstract

The roughness coefficient of the concrete irrigation canal is one of the important evaluation criteria to ensure the hydraulic performance or malfunction between water and wall surface.In this study, the roughness coefficient of the concrete irrigation canal was measured using the aerial ultrasonic wave of the transceiver type sensor. The effect of the dispersion of measurement values in relation to the arithmetical mean roughness and the peak to peak value of the reflected wave were demonstrated. The influence of wet and dry conditionsof concrete surface and the verification of the measurement range were taken into account. Results obtained showed that the peak to peak value of the reflected wave could measure the arithmetical mean roughness of concrete. It was observed that the average of 15 measured values was sufficient for accuracy. The peak to peak value of the reflected wave was affected slightly under wet condition. The range of the measured diameter of aerial ultrasonic wave sensor was approximately 300 mm and 600 mm from the distance of 550mm and 1000 mm respectively.It is concluded that the development of the measurement method of arithmetical mean roughness of concrete surface by the transceiver type aerial ultrasonic sensor can be achieved.