The Research Of Subgrade Compaction Continuous Automatic Technology

With the development of highway construction, highway construction quality problems are more attracted attention. Insufficient degree of compaction is one of the important causes of early pavement damage. Compaction job is to make each of the roadbed and road construction materials sufficient density of an important part of the use of effective detection method of compaction is an important means of monitoring its implementation.The paper, degree of compaction detection methods based on the research results presented by vehicle type Compactness continuous real-time detection system to measure the degree of compaction of the soil, the advantage that convenient, fast, and accurate compaction Full of continuous detection, in order to facilitate the compaction quality control.Through theoretical analysis and laboratory tests designed to detect the degree of compaction of the vehicle-mounted system basic configuration; determining the analysis and processing technologies- sensors, signal acquisition instrument selection and parameter data signal. In the system calibration test, shaking table test, based on the degree of completion of the vehicle-mounted compaction continuous monitoring system. Field test confirmed the accuracy and reliability of the system.The main conclusions are as follows:① wheel vibration excitation signal change reflects the degree of compaction of the soil, through excitation signal analysis and processing to reflect the actual degree of compaction method is correct and feasible.② By analyzing the actual excitation signal indicates: the degree of compaction of subgrade soil stiffness and a positive correlation, and negative damping soil; and vibratory compactor vertical vibration acceleration and the soil stiffness positively correlated with soil damping negative. Based on the above analysis of the results of the establishment of the "vibratory roller- soil" model and simulation analysis, the degree of compaction roller vertical vibration acceleration and vibration subgrade positive relationship.③ proposes the application of vibratory roller vertical acceleration sensors, data logger, computer data processing and analysis system continuously detected compaction system, compaction degree continuous detection technology. Processing and analysis techniques proposed acceleration detection data.④ proposed vertical vibration acceleration with a vibration roller compacted soil compaction rms, acceleration techniques and methods of harmonic ratio indicates the degree of soil compaction. Get three different graded sand class under different conditions of optimum moisture content of the soil compaction and vibration wheel vertical regression formula and correlation coefficient between the RMS value of acceleration, the degree of compaction and vibration wheel vertical acceleration, the degree of compaction harmonic ratio between the acceleration and the regression formula and correlation coefficient are shown below.⑤ relations put forward different fines content(hx) gravel soil compaction y acceleration RMS between a regression using the following formula.