Abstract:
In this research, we designed and constructed the CBR and Marshall standard testing machine, which can test for two different standards in the same machine by using 3 phases stepping servo motor. A mechanical adjustment gear velocity was controlled by electrical frequency and converted the angular to the linear velocity. The average velocity of was calculated from a slope of the graph between distance and testing time. The experimental results showed that three average velocities: CBR-TEST are 1.00 mm/min, and 1.27 mm/min and Marshall-Test is 50.57 mm/min compared with three velocities of the standard testing are 1.00 mm/min, 1.27 mm/min and Marshall-Test is 50.80 mm/min respectively. The percentage error of experimental results compared with the standard values are 0.24, 1.34 and 0.46 respectively.