Aashto design traffic load equivalence factor lef the ratio of the effect damage of a specific axle load on pavement serviceability to the effect produced by an 18kip axle load at the aasho road test. When the system is not moving, the sum of all forces and torques equals 0. For highways the maximum legal axle load in india, specified by irc, is 10 tonnes. Pavement design guide me pdg utilizes axle load spectra to characterize the. It is a single axle load with dual wheel carrying 80 kn load and the design of pavement is based on the standard axle load. Calculate the load factor for each vehicle category 6. Deacon, assistant professor of civil engineering, university of kentucky. When there is a torque equilibrium around the centre of the wheel, the following. The conversion of traffic to the esal is accomplished with the use of axle load equivalency factors. Based on axle load studies previously undertaken in bangladesh, the following.
Axle load calculations general information about axle load calculations 04. Deen, assistant director of research, kentucky department of highways one significant means for evaluating the relative destructive effects of repetitive vehicular loading on highway pavements is. Axle load analysis for bituminous pavement design youtube. The maximum allowed axle load on the roads is called legal axle load. Texas flexible pavement design system windows or aashto design procedure, darwin 3. Effective 40104 61 alaska flexible pavement design manual 6. Esal is the acronym for equivalent single axle load. Since axle load data are not available for all roadways throughout the state, the data available are combined to give a figure. The magnitude of the axle load and the number of load repetitions are major factors in the performance of a flexible pavement structure. Pdf the effect of axle load spectra from aashto method.
Pavement thickness must be designed to withstand the anticipated traffic, categorized by type and weight of vehicles, and measured by average daily volume adv of each type for the design life of the pavement. For most pavements, the magnitude of the axle load is of greater importance than the gross. Pdf currently, methods used for pavement design are empirical and based on experiments conducted in the 1960s. For pavement design purposes all heavy commercial vehicles are expressed in terms of the equivalent number of standard axles that they represent. Proper consideration of traffic loading in pavement design requires knowledge of the full axle load distribution by the main axle types, including single, tandem, and tridem axles.