Turq –
A very interesting question!
The precise turning radius and wheel base (width) depends on whether
the tractor is a yard or over-the-road tractor. Yard tractors are
designed for tighter turning bases, often as little as 32’:
Ottawa Truck
"Frequently Asked Questions"
http://www.ottawatruck.com/about_us/faqs.html
Even with over-the-road trucks, design will vary the turning radius.
Standard-cab trucks tend to be longer (think Kenworth); cab-over
designs tend to have shorter wheelbases.
However, we can thank the American Association of State Highway and
Transportation Officials (AASHTO) for setting design standards for
roads. They have a "standard" 18-wheeler’s dimensions for road
planning and it’s termed a WB-50 design. In highway design they plan
a WB-50 to be (per 2001 standards):
53’ long (wheelbase – not total length)
8.5’ wide
45’ turning radius
The wide of road lanes is typically 15’, though the truck requires
only 8.5’ of pavement.
This civil engineering presentation talks about lane widths and
turning radius for street design:
Wayne State University
"Transportation Design" (Prof. Tappan Datta, Fall 2002)
www.eng.wayne.edu/coe/forms/4/ CE4640_Class_Slides_2111.ppt
This presentation on dock design notes that in backing, the turning
radius may be as high as 80’. It contains a more complete description
of vehicle length (the WB-50 design ignores the rear overhang of a
vehicle, so underestimates overall length) as being about 66’.
Valley Forge Laboratories, Inc.
"Tractor Trailer Reverse Motion Path" (undated)
www.valleyforgelabs.com/reverse_movement.pdf
Google search strategy:
"tractor trailer" + "turning radius"
"WB-50" + AASHTO
Best regards,
Omnivorous-GA |
