Research On Subgrade Compactness Detection System

Vibratory compaction is widely used in highway engineering as a rapid and efficient pressure method.The compaction quality largely determines the service life of the highway.The compaction degree is an important index to measure the quality of compaction operations.The importance of its detection process is self-evident.Due to the lag of the detection and the representativeness of the sampling,the traditional compactness testing method makes the detection of compaction time-consuming and low-accuracy,and can not reflect the compaction quality of the roadbed as a whole.This article proposes a compaction degree for this deficiency.Continuous detection technology can achieve continuous non-destructive testing of compaction,and can eliminate signal interference caused by different ground stiffness,laying the foundation for future development of intelligent compaction.In this paper,starting from the study of vibratory compaction mechanism,the influence of many factors on the compaction effect during the vibratory compaction process is analyzed.By analyzing the two-degree-of-freedom dynamic model of "vibrating wheel-pressed material",it is known that the acceleration of the vibrating wheel is closely related to the stiffness and damping of the pressed material,which provides the basis for the continuous measurement technology of compaction degree.In this paper,the vibration compaction power of the vibratory roller is used to reflect its compaction capacity,and the different effects of the roller compaction direction on the compaction effect during the actual compaction operation are analyzed.Through Matlab/Simulink simulation of two-degree-of-freedom dynamic model,combined with the test results,we can know the correlation between vibration acceleration amplitude and compaction degree.Study the principle and structure of the compactness continuous detection system.Acquire the vibration acceleration signal and analyze its characteristics.Design a curve-fit frequency domain filter algorithm to filter the signal to obtain the most realistic vibration acceleration signal.Use Matlab to simulate and simulate.Verify its effectiveness.Finally,a continuous measurement test for compaction degree was performed.The data analysis was performed using the amplitude method and the amplitude increment method,respectively,to obtain an acceleration index that can evaluate the degree of compaction;this error wasanalyzed to verify its reliability.In order to eliminate the acceleration signal interference caused by different ground stiffness,this paper finally determines the continuous detection of compaction using amplitude increment method.