Research On Control System Of Asphalt Mixture Bending Creep Test Based On The Microcontroller C8051F410

Bending Creep Test of Asphalt Mixture is used for the determination of Bending creep rate of hot asphalt mixture specimens at the prescribed temperature and load conditions, in order to evaluate the deformation properties of asphalt mixture.The testing datas which are used as references should be true and correct.At present, the test is widely applied in domestic highway construction.In this paper, do the following work:First, the experimental principle and the required testing conditions were analyzed under T0728-2000 bending creep testing rules, then the developing circumstances of this test in internal highway construction were introduced.Secondly, in the part of system hardware design, the core of the control circuit C8051F410 was introduced, including I/O circuit, displacement measurement circuit,circuit of the expansive memory, liquid crystal circuit, circuit of the temperature measure, Real-Time Clock circuit and Keyboard circuit etc.The system software is written by C language including data gathered, data analyzed and processed, Temperature Measurement and Control, Real-Time Clock and the liquid crystal display etc.The main control system realized the loading, testing, protection, temperature control, judgments and unloading.Master computer control system based on Visual Basic6.0 was developed to achieve the slave computer start, stop and self-test, data uploads and other operations as well as the test data display, storage, test curve real-time rendering, partial zoom, curve printing, data processing and the test report output to print, the historical record of the calls and other functions.Thirdly, research on LCD curve drawing algorithm, discontinuous point convergence algorithm, real-time clock algorithm, the background color image processing algorithms were made.Finally, software of MATLAB and Simulink were introduced. Carried on the Temperature control system simulation, compared with result of the general PID control, and fuzzy-PID control,the latter obviously surpasses former.The paper introduced the Fuzzy-PID control algorithm into Bending creep control system, improved the control efficiency. The control function of the system has mostly reached the measurement level of the commonly used bending creep test machine, stable and reliable, high precision, simple operation, fully meeting the national standard on the technical specifications. Master computer control system is good for easy operation,friendly interface and facilitate data processing.In this paper, bending creep test as the background, the loading system, water system, temperature control systems, data measuring system, test monitoring system, and all referred to the micro controller, and Master computer control system soft is designed to achieve the integration of the measurement control and Monitoring.