Hazard Of Overload On The Asphalt Pavement

Though the overloaded transportation problem has already caused the extensive attention of the different fields, it has never had a quantitative answer to the degree of the harm and the deduction of the fatigue life under the function of overloaded vehicles. For this purpose, the project which based on the current traffic condition analyses the using characteristics of asphalt pavement, makes the rational assessment and puts forward the corresponding countermeasures of this problems. Firstly, by abundant investigations the causion and the hazard of surcharge is systematic analysised. Secondly, the inner pavement stress caused by the overloaded vehicles is always influenced by the interval time, stress level and the temperature ,and close to the fact of the ultimate stress of bituminous mixture and frequency of the overloaded vehicles. The result of the fatigue test of the bituminous mixture under the high-stress ratio indicates that it can't continue to use the low-stress fatigue equation. The project offers the fatigue equation 0S, 1S under the high-stress ratio through the regression analysis of the test data. Finally, it uses the 3D finite element computational method to analyse the five characteristics of asphalt surface courses under overloaded vehicles: causes the stress of the inner pavement structural increases largely, so great with the base course; the great increment deflection of the pavement surface .The little increment of Axle-load will lead to the thickness of structure raise greatly; Great influence of rut on pavement is caused and early destruction is riser; reduce the service life of the pavement, for instance, a 12 year's pavement under normal condition, but not enough than 2 years with 50% overloaded rate and 1 year relies on the indexes of tensile stress and rut; it may cause the ultimate damage of the pavement. Based on the three aspects of the research results mentioned above and diversely investigation, it systematic analyses the reasons and hazards of the overloaded. According to the three aspects of the researching result above, technological countermeasures aiming for the overloaded destruction that can be easily carried out are put forward. The project has extremely strong realistic meaning, and the results can be used for the reference to the pavement designers and the managers.