Research On Real-time Continuous Detection Technology Of Asphalt Concrete Compactness

In highway engineering,compaction is the key process to ensure the quality of highway construction and affect the service life of highway.However,the traditional testing methods of asphalt concrete pavement compactness have some disadvantages,such as high destructive,high cost and affecting construction quality.Therefore,it is necessary to study new detection methods as soon as possible to achieve non-destructive real-time dynamic monitoring of asphalt concrete compactness.In this paper,the realtime continuous testing technology of asphalt concrete compactness is taken as the research object,and the following contents are studied:(1)Through theoretical analysis,the dynamic model of "asphalt concrete-vibrating roller" system is established.Through studying its dynamic equation,the theory of measuring the compactness of asphalt concrete by vibration acceleration is feasible and effective,and the real-time continuous testing technology system of asphalt concrete compactness is established;(2)Through matlab software,the simulation program of vibration compaction process is compiled.By running the program,the image between stiffness,damping and vibration acceleration of asphalt concrete pavement is obtained.And the image illustrates the relationship between stiffness,damping and acceleration,and verifies the rationality of the theoretical basis;(3)Taking Da’an Town-Ping’ancheng Construction Section of Qin-Jing Expressway Project as a project to collect the field vibration acceleration signals,and filtering the measured acceleration values with IIR filter and sliding average filter.The valid value of acceleration is obtained and compared with the simulation results,which consolidates the theoretical basis;(4)By analyzing the relationship between compactness and acceleration effective value,the fitting equations of compactness and acceleration of asphalt concrete with three different surface designs are obtained.(5)By studying the influence of different surface design on the relationship between compactness and acceleration of asphalt concrete.The fitting equation of compactness and acceleration of asphalt concrete is established based on the ratio of asphalt concrete surface thickness(d)to nominal maximum particle size(NMAS)(d/N).In summary,the content of this paper is helpful to improve the construction efficiency and quality of the compaction of asphalt concrete pavement in highway engineering,and provides theoretical basis and data support for real-time dynamic monitoring of compaction degree.