Research On Vibratory Roller On-line Detection System Based On LabVLEW

The vibration compaction of road roller is an important part of modern road construction, Paving quality of asphalt pavement directly determines the life of the road and driving safety. The main factors affecting the level of the road pavement quality is the degree of compaction is good or bad. The degree of compaction is a kind of physical quantities that can characterize the degree of compaction of material. Therefore, accurate and efficient detection of compaction is the key to ensure the quality of this job. With the rapid development of science and technology, and substantial increase in the level of mechanization of road construction and advanced use of shipment, paving, compaction machinery, road paving speed constantly improve, and requirements on the road construction machinery are increasingly high. Using the traditional method of compaction quality testing is often difficult to meet the requirements of the construction and timely guidance.The traditional pavement compaction detection takes some methods, such as sand-pouring method, cutting ring method and wax sealing method. These methods have two shortcomings: lag of detection methods and limitations of the detection point. Detection method is to sample after the paved road finished, and such detection takes longer, the result of degree of compaction cannot be given in a timely manner; Detection point is simply random data sampling, which may result in missed part of the road, and cannot guarantee the quality of construction of all sections. For the shortcomings of traditional detection techniques, a continuous, accurate and rapid detection of compaction equipment is developed; it has important practical significance for conducting a comprehensive real-time monitoring of compaction quality of the road.In this paper, drawing on the relevant testing methods of degree of compaction and research results at home and abroad, on the basis of these, the real-time detection system design of vibratory roller completed based on Lab VIEW.In the first place, it combined with the relational model of two degrees of freedom “roller- was pressed materials”, and analyzed of the mathematical relationship between the vibration wheel acceleration signal and material stiffness, and focused on common principles of domestic and foreign R & D compaction meter, finally the amplitude method with a good correlation was be chosen by comparison test. According to the working characteristics of vibratory roller, to combine with asphalt paving process, to select wheel vibration excitation signal as the signal source to detect the degree of compaction, and to analyze the magnitude of this signal to order the degree of compaction, all these provide a theoretical basis for compaction testing.Secondly, for the needs of this test system, discussed the measuring principle of taking sensor during the test and the selection and installation of sensor. Focus of paper is on the research formation of the test system from two aspects, hardware and software. Built of hardware platform includes three parts, a sensor module, signal conditioning modules and data acquisition modules, and using virtual instrument test technology to collect experimental data; and in other aspects, software, taking the modular design approach, the degree of compaction testing system designed in the Lab VIEW, each function of the system is assigned to each of the functional modules, including the initialization parameters, filtering, time domain and frequency domain analysis, the signal stored, data playback, and it is by calling on the different modules of the system to achieve the test run, the signal acquisition, data processing, data analysis and the results showed. On detection algorithm, by the least squares fitting algorithms to get the corresponding relationship between the acceleration voltage value and actual compaction measured values, and by the algorithm program, actual compaction measured values has gotten eventually.Finally, through the simulation signal, debug and validate the online detection system of designed vibratory roller. The results show that this test system design is feasible, and it can accomplish data collection and analysis well by using this system, and also it can meet the requirement of online detection of compaction degree during the road construction.