A methodology for the evaluation of the economic impact of overweight permitted vehicles hauling agricultural products on state highways is presented in this study. The different gross vehicle weight scenarios that ar...A methodology for the evaluation of the economic impact of overweight permitted vehicles hauling agricultural products on state highways is presented in this study. The different gross vehicle weight scenarios that are selected for this investigation range between 80,000 lb. and 100,000 lb. Uniform distribution of axle loads and lumped loads are considered in this study. This study evaluates the proposed higher truck loads and their economic impact to the highways and to the industry. The effects of adapting higher truck loads on the existing highways are evaluated using a deterministic load capacity evaluation as well as a reliability assessment. The target reliability level is derived from AASHTO （American Association of State Highway and Transportation Officials） standard design specifications to satisfy safe and adequate performance level. The overlay thickness required to carry traffic from each gross vehicle weight scenario for the overlay design period is determined. Differences in overlay life were calculated for different gross vehicle weight scenarios with uniform and lumped axle loads. The overlay thickness and costs were determined for a twenty year analysis period using statistical methods. The result showed that lumped loads with allowable axle load of 48,000 lb. produce more pavement damage than the current permitted gross vehicle weight for timber trucks with equally loaded axles.展开更多
The fast-growing economy and the gradually established highway system have boosted the road trans- portation for both passenger and cargo over the last decade in China. From 2000 to 2010 Chinese GDP increased by aroun...The fast-growing economy and the gradually established highway system have boosted the road trans- portation for both passenger and cargo over the last decade in China. From 2000 to 2010 Chinese GDP increased by around 10.15% annually and the sales of medium and heavy trucks by around 18.87% （sales increased from 0.2 million in 2000 to 1.3 million in 2010） according to the National Bureau of Statistics of People＇s Republic of China. Today commercial vehicles consume almost the same amount of fuel as pas- senger cars in China although the number of commercial vehicles is only about one fourth of passenger cars. It is estimated that around 50% of imported fuel to China each year will be consumed by vehicle transportation. This si- tuation will worsen fuel shortage problems in the long run and at the same time it is partially responsible for the ever- worsening air pollution in China. Due to the widespread overloading in China, lightweight development in commer- cial vehicles has fallen far behind that of passenger cars with the consequences that Chinese commercial vehicles consume in average about 20% more fuel, especially the heavy trucks, compared to European models. Under these circumstances it is essential to reduce the vehicle fuel consumption and in- crease the transport efficiency. The key solution thereby is to implement lightweight design in commercial vehicles as it has been successfully practiced over the last decade in the passenger cars. This paper summarizes highlights given in presentations during the ＂International seminar on the ap- plication of high strength steels in light weight commercial vehicles＂ with the focus on the development and application of Nb alloyed high performance steels made for lightweight commercial vehicles.展开更多
文摘A methodology for the evaluation of the economic impact of overweight permitted vehicles hauling agricultural products on state highways is presented in this study. The different gross vehicle weight scenarios that are selected for this investigation range between 80,000 lb. and 100,000 lb. Uniform distribution of axle loads and lumped loads are considered in this study. This study evaluates the proposed higher truck loads and their economic impact to the highways and to the industry. The effects of adapting higher truck loads on the existing highways are evaluated using a deterministic load capacity evaluation as well as a reliability assessment. The target reliability level is derived from AASHTO （American Association of State Highway and Transportation Officials） standard design specifications to satisfy safe and adequate performance level. The overlay thickness required to carry traffic from each gross vehicle weight scenario for the overlay design period is determined. Differences in overlay life were calculated for different gross vehicle weight scenarios with uniform and lumped axle loads. The overlay thickness and costs were determined for a twenty year analysis period using statistical methods. The result showed that lumped loads with allowable axle load of 48,000 lb. produce more pavement damage than the current permitted gross vehicle weight for timber trucks with equally loaded axles.
文摘The fast-growing economy and the gradually established highway system have boosted the road trans- portation for both passenger and cargo over the last decade in China. From 2000 to 2010 Chinese GDP increased by around 10.15% annually and the sales of medium and heavy trucks by around 18.87% （sales increased from 0.2 million in 2000 to 1.3 million in 2010） according to the National Bureau of Statistics of People＇s Republic of China. Today commercial vehicles consume almost the same amount of fuel as pas- senger cars in China although the number of commercial vehicles is only about one fourth of passenger cars. It is estimated that around 50% of imported fuel to China each year will be consumed by vehicle transportation. This si- tuation will worsen fuel shortage problems in the long run and at the same time it is partially responsible for the ever- worsening air pollution in China. Due to the widespread overloading in China, lightweight development in commer- cial vehicles has fallen far behind that of passenger cars with the consequences that Chinese commercial vehicles consume in average about 20% more fuel, especially the heavy trucks, compared to European models. Under these circumstances it is essential to reduce the vehicle fuel consumption and in- crease the transport efficiency. The key solution thereby is to implement lightweight design in commercial vehicles as it has been successfully practiced over the last decade in the passenger cars. This paper summarizes highlights given in presentations during the ＂International seminar on the ap- plication of high strength steels in light weight commercial vehicles＂ with the focus on the development and application of Nb alloyed high performance steels made for lightweight commercial vehicles.
