Simulation And Design Of Pavement Accelerated Loading Testing Facility

In the situation of economic construction development, with the increase of traffic volume, speed, axle number and load, the road is under increasing load, and the service life of the road will be shortened accordingly. In order to study the reasonable pavement structure and damage mechanism, reduce the construction and maintenance costs, get the optimization of pavement performance, it is necessary to take accelerated loading testing on the pavement structures and materials. ALT facility is a new kind of pavement accelerated loading testing facility. It can apply controlled axle load and change the running speed and the number of times to test different pavement structures, materials and surface states. It can get the change process, mechanism and damage state of the pavement, and analyze the status change and failure process when the pavement under a repeat loading.Firstly, dynamic simulation analysis software ADAMS is used to model and simulate the loading part of the ALT facility.The reaction between tire and road is studied in the aspects of the static load and dynamic load. Because of the effect of road roughness, loading part can cause vibration in the movement process during dynamic loading. Dynamic tyre force value approximate to the same condition of static tire force value. The vibration is influenced by running speed, load and tire coefficient.Secondly, the mechanical and hydraulic system are designed for ALT facility loading system. The parts of mechanical system are introduced, and the technical requirements and solutions of the loading hydraulic system and auxiliary hydraulic system are put forward. The action which hydraulic system need to complete is analysed, and main hydraulic components are calculated and chosen.Finally, the control system of ALT facility is designed. Control system is composed of master control system,transverse control system and data acquisition system. PLC and frequency converter are used to control the drive motor of the loading vehicle in the main control system, so as to ensure the stability of running speed; non-contact control devices are used to implement the simulation of the transverse normal distribution of the wheel track in the transverse control system; because of the high reliability, CAN bus technology is adopted in data acquisition system, which can improve the testing accuracy and efficiency.