Design and Realization of the Sub-grade Compaction Measuring Equipment Based on STM32
WAN Jian-jun;XIAO Wei-chu;HE Jian-quan;LIU Zhi-ming;YANG Tong-song;College of Communication and Electronic Engineering, Hunan City University;
For the problems of complex operation, the destructive testing and long-time measurement existing in the traditional sub-grade compaction measuring equipment, the equipment of measuring degree of compaction quickly with a simple operation and no damage to the roadbed was developed. It selected different roadbeds by touching a graphical user interface. The motor controlled by MCU drove the drop hammer and the drop hammer was raised to a fixed position, then it freefell. the drop hammer produced the fixed impact which made the guide rod into the ground. At the same time, the Ultrasonic module measured the dropped displacement of the guide rod by using the time difference method. MCU converted the displacement into degree of compaction and transmit it to LED for display. The test results showed that this equipment implemented the measurement of degree of compaction for different roadbeds with the average error of 0.54.