TRAFFIC ABILITY OF HEAVY VEHICLES ON AN INCLINE

摘要

Traffic ability of heavy vehicles on steep hills is of great concern in Norway due to its geography, which is characterized by many mountain passes and inclines. Vehicles stopping in the roadway are a significant problem on many roads in winter time, and this has led the Norwegian Public Roads Administration to implement a project that begins to examine what factors influence the ability of trucks to keep moving under poor driving conditions during the winter season.Four vehicles with different axle configurations were used in the experiments carried out in February 2009:1. Bogie truck with 3-axled trailer2. Semi-trailer with bogie and 3-axled trailer3. Semi-trailer without bogie, and 3-axled trailer4. Pusher truck with bogie and 3-axled trailerThe experiments included the following configurations for vehicles 1-3:1. Vehicle and trailer without cargo2. 10 tonnes of cargo3. 20 tonnes of cargo4. With and without use of bogie (vehicles 1 and 2)The results show that the weight on the driving wheels is decisive with regard to whether the vehicle is able to reach the top of the gradient or not. The tests also demonstrate clearly the great advantage of having a vehicle with bogie. Raising the bogie significantly increases the weight on the driving wheels, and this makes it easier to maintain speed up the gradient. Often it is an advantage to increase the pressure of an axle beyond 10 tonnes, which is the limit on many Norwegian roads.