Vibration Analysis Of The Ground Generated By The Vehicles Crossing Speed Control Humps

With the development of the transportation in China, more roads are built every year, and more residents have bought family cars, at the same time, environmental vibration caused by the traffic loads is becoming serious. The speed-control humps are installed to control the speed of vehicles in residential areas, schools, and road intersections. As speed-control humps effectively used, they bring side effects on pavements, vehicles and car owners. This article analyze mechanics of the generation of the vibration while vehicles crossing speed-control humps, and proposes the three-stages model, that's horizontal impact-vertical vibration-vertical impact. Experiment is designed to verify the hypothesis.The three-stage model is roughly as follows:Triangular load is used to stimulate the loads in the two stages of horizontal impact and vertical impact; dynamic axial load is used to stimulate the force in the stage of vertical vibration. Then these three loads are resolved into a series of harmonic forces, submitted in the equation of stiffness matrix of layered soil to calculate the displacement peak values of the soil surface.To test the validity of the model, In-situ measurement is designed and vibration signals are recorded. The test is designed as follows:The vehicle crossed speed control humps at 10km/h,20km/h,30km/h,40km/h,50km/h, and 60km/h separately, and equipment was set aside to record displacement signals, velocity signals, and acceleration signals. For the sake of accuracy, each case was tested twice.Then data collected were analyzed mainly in three respects:Time-interval between front and rear wheels passing humps; the relation between peak values and the velocity of the vehicle; the duration of the three stags; peak values of the three separate stages, contrast between calculation and measurement.