Abnormal Vibration Of The Dump Truck

This thesis is aimed to solve abnormal vibration of moving dump trucksmanufactured by an auto-factory, the reason caused the vibration was found by theoreticalanalysis, modal experiments and road tests, and then some reference that could reduce thevibration and improve the overall performance of the truck was proposed.The thesis reviewed researches related to abnormal vibration of moving dump trucks.Through theoretically analysis of the vibration source of the dump truck, it was found thatvibrating sub-systems including engine assembly, power chain assembly may causevibration frequency and pattern; by using modal experimental method, a modalexperiment system of the dump truck was established, and some modal experiments weresuccessfully conducted. The unevenness of road was measured using fifth-wheel system,fitting characteristic values and frequency multiplication values of the segment of the testroad were obtained.Several road tests of the dump truck was successfully conducted, the main reasonthat caused the abnormal vibration of the truck were as follows: mass unbalance ofwheels causes abnormal vibration (5.214Hz and 5.649Hz) at the vehicle speeds of 60km/hor 65km/h, the frequency of the vibration caused by road unevenness equal to the firstorder and second order of the natural frequency of the frame of the truck.