AASHTO design vehicles

[nutbutter]

Do these values incorporate the weight of a fully-loaded vehicles or are they just the empty vehicles.

For instance, the HS20-44 design vehicle has axle weights of 8kip, 32kip, and 32kip. Are these the axle weights for the fully loaded vehicle, or are these the axle weights for the empty vehicle?

 

[Qshake]

They are simply design vehicles, it doesn't matter if the trailer is full or not. The only reason one would ask is because of the picture....which is only helpful in showing the variables.

You are not likely going to find an actual truck matching the exact dimensions/weight. Most oversize trucks have way more axles than does the design vehicle. Even dump trucks have a third back axle that engages with ultra heavy loads.

Regards,
Qshake

Eng-Tips Forums:Real Solutions for Real Problems Really Quick.

 

[rconner]

Can't answer for AASHTO, but I believe the design weights/distribution are intended to reflect loaded truck weights, perhaps even with reasonable conservatism (in distribution etc. as hereinbefore explained) as to effects on structures.

 

[jdonville]

As recently explained to me in a LRFD class, the "design vehicles" simply represent loading conditions that produce a representative extreme response in the structure (including pavement structure) under consideration. The fact that they are illustrated as being discrete vehicles is misleading and should be ignored.

Jeff

 

[Ron]

Design values are for loads...doesn't matter if the truck is empty or full (though the concept contemplates a loaded vehicle), as long as it exerts those loads on the pavement.

 

[DRC1]

Typical vehical wt is 20tons load typically 20 tons legal load w/o permit is 40 ton , hence vehicles are loaded AASHTO LRFD requires HL-93 which is HS-20 plus Lane load w/o concentrated load.