Research On Asphalt Pavement Roughness Evaluation Method Based On Full-car Model

Pavement roughness of road has a significant influence on vehicle vibration,human body comfort and pavement life. Asphalt pavement roughness evaluation IRIcurrent widespread use of ride comfort associated with the poor, and the IRI is usedto calculate1/4passenger vehicle models are not representative of other defects. Inaddition, the existing asphalt pavement roughness evaluation method is moretheoretical method, the establishment of a simplified model for the study of multi-degree of freedom of the vehicle, while the vehicle models are simplified as a rigidbody with a focus on the body mass, ignoring the body based on front and reartransverse vibration and vibration, and larger tires tire model and the actualdifference, therefore, the use of dynamic simulation software-vehicle-roadinteractions relative to the theoretical simulation method is more close to reality. Forbridge transition section, although the researchers conducted a number of studiesbridge jumping, but has not yet put forward a unified permit differential settlement;researchers have proposed the maximum transient vibration value as a bridgetransition section evaluation, but has not yet given the indicators grading criteria. Foreach of the above problems, this paper proposes the use of a vehicle model vehicle-vehicle-road interaction simulation, and propose a normal road and bridge transitionsection of asphalt pavement evaluation methods.In this paper, the human body weighted rms acceleration, maximum transientvibration value MTVV were used as normal asphalt road and bridge transition sectionflatness evaluation. Relying on three different levels of Zhejiang Fuyang tests werenormal road sections inside the vehicle acceleration data acquisition test and roadroughness absolute elevation data acquisition test, the acceleration data processing todetermine the different sections of the speed of cars and trucks in different humancomfort. Settlement of differences between the more serious bridge transition sectionelevation measurements, provide the basis for subsequent modeling of bridgetransition section of the road. Then, using a vehicle simulation software Carsim,Trucksim by modifying the basic vehicle model body, tires, steering suspensionsystem parameters brake system, transmission system and aerodynamic build seven subsystems test car, the whole truck car vehicle models; and use of software modulesto set the centerline of the road elevation, road roughness and surface properties ofparameters such as the establishment of normal sections of the road model; furtheruse of the vehicle model and road model were human-vehicle-road interactionsimulation, seat acceleration data collection. The field test data collected accelerationsimulation results were compared with the results of the analysis, And the results ofsimulation test and field test are studied comparatively, the results shows that carsimulation and experimental results correlation coefficient is0.943, truck simulationresults and experimental results correlation coefficient is0.767. In addition, thecorrelation between the weighted RMS and another two wide used roughnessevaluation index in our country is studied, the results shows that the correlationcoefficient between weighted RMS and IRI, standard deviation of roughness are asfollows:0.903,0.859.For bridge-subgrade transition section, this paper uses the maximum transientvibration value (MTVV) as the evaluation index, takes the tolerable differentialmovement of the embankment interface and the tolerable differential slope of theapproach slab as the tolerable differential settlement when with and without theapproach slab respectively. And by analyzing the tolerable differential settlement athome and abroad, the simulation working condition of bridge-subgrade transitionsection are given, and then the human-vehicle-road interaction simulation test is done.According to the simulation results, the MTVV is calculated and the influencesparameters are analyzed. Then relying on Jing-Gang-Ao and Zheng-Jiao-Jin highways,the correlation between comfort rating value and MTVV is studied, and thenaccording to the comfort score subjective feelings corresponding values the MTVVgrading is given. Therefore the tolerable differential settlement of bridge-subgradetransition section is determined.Finally, according to the above study, for normal road section, use weightedRMS as the asphalt pavement roughness index, and the field measured evaluationmethod and simulation evaluation methods are proposed. And for bridge-subgradetransition section, takes MTVV as the asphalt pavement roughness evaluation index, and the simulation evaluation method, field measured evaluation and simpleassessment method are proposed.