With caving method determination of fine aggregate (mechanism of natural sand, sand and stone chips) in 23 ° to water, gross relative density apparent relative density, volume table dry relative density (saturated surface relative density). Test mechanism of natural sand, sand and stone chips are in a state of saturated surface of the water absorption.

Xi’an Zealchon Electronic Technology Co.,Ltd adhering to the "professional,  honest, and providing the best service" business philosophy, with the guidance of professors and researchers from the Well-known institutions in China,      developed a series of leading domestic and international standards, Technology class detecting instrument for asphalt and asphalt mixture, Road, bridge deck, geotechnical, structural, etc and OEM designed 12 series more than 100 kinds of laser productswith high power and long service time.