Type "S" Dump Truck Loading on Bridge
Type "S" Dump Truck Loading on Bridge
(OP)
Hi everyone,
I am designing a bridge with a simple span of 80 feet. the AASHTO loading is not a problem and is applied by the Book. The owner wants an type 3 dump truck loading applied also . the "type 3" weighs 33 tons (66000lb) front axle=14kips middle axle=26 kips and 12 feet away from front axle and the rear axle is also 26kips and 4 feet away from the middle axle.
I understand the type 3 truck is one of the FHWA loadings that some states have adopted. You see I really havent dealt with anything but HS trucks.
This might sound somewhat elementry but how do you apply this load?? do you put one truck in the middle like is done with AASHTO HS truck? You see, with an HS truck there is also a lane loading which modles a train of trucks back to back when the span is long enough. but in this case there is no lane loading (and if there is I dont know about it) and the Span is long enough to accomodate at least three or even four trucks with reasonable distance between them. and as you might have observed dump trucks more or less haul in convoys.
PLEASE HELP !
Thank you very much
I am designing a bridge with a simple span of 80 feet. the AASHTO loading is not a problem and is applied by the Book. The owner wants an type 3 dump truck loading applied also . the "type 3" weighs 33 tons (66000lb) front axle=14kips middle axle=26 kips and 12 feet away from front axle and the rear axle is also 26kips and 4 feet away from the middle axle.
I understand the type 3 truck is one of the FHWA loadings that some states have adopted. You see I really havent dealt with anything but HS trucks.
This might sound somewhat elementry but how do you apply this load?? do you put one truck in the middle like is done with AASHTO HS truck? You see, with an HS truck there is also a lane loading which modles a train of trucks back to back when the span is long enough. but in this case there is no lane loading (and if there is I dont know about it) and the Span is long enough to accomodate at least three or even four trucks with reasonable distance between them. and as you might have observed dump trucks more or less haul in convoys.
PLEASE HELP !
Thank you very much






RE: Type "S" Dump Truck Loading on Bridge
It is a TYPE 3 truck
My apologies
RE: Type "S" Dump Truck Loading on Bridge
I would recommend that you do some more investigation and determine what, if any, lane load exist. As you are probably aware a concentrated load accompanies the lane load. A single for maximum positive moment and two concentrated loads for maximum negative. The latter, of course, you won't need to bother with. The former may be of some interest depending on the values as it may exceed the truck loading. I would try www.fhwa.org first for some more information.
RE: Type "S" Dump Truck Loading on Bridge
RE: Type "S" Dump Truck Loading on Bridge
RE: Type "S" Dump Truck Loading on Bridge
The thread was initiated as one of the steps in trying to find out if there is a lane load for this truck.
No answer is better than a non-answer
RE: Type "S" Dump Truck Loading on Bridge
As for your comment of "no answer...". Answering the reading understanding and answering question is the essence of this forum, not criticizing others for what amounts to your own laziness!
RE: Type "S" Dump Truck Loading on Bridge
Later in the post in that paragraph you introduce the lane load for the Type 3 truck.
I did get the website incorrect. I suggest that you check out www.enron.com for a new career.
RE: Type "S" Dump Truck Loading on Bridge
RE: Type "S" Dump Truck Loading on Bridge
If you've phoned and looked up the FHWA document that explains the Type S (or 3) Truck at the FHWA publication website and still haven't found an answer...maybe your client knows.