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Tractor trailer min turn radius in tight quarters ?

Milacron

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Driveway behind building is 28' wide, driveway on far side of building is 46' wide. So, can the longest standard tractor trailer pull into 28' wide driveway behind building (straight shot, easy turn, from highway) and keep going behind the building, and then turn right around the building into the 46' section, and exit the side road ? Without crunching the trailer into the edge of the building. Looks pretty iffy to me.
 
Not being a smart ass here, but are we talking highway articulated (semi) truck and trailer type tractor or agricultural tractor & trailer?
 
Not being a smart ass here, but are we talking highway articulated (semi) truck and trailer type tractor or agricultural tractor & trailer?
I suppose "highway"...but it would even depend on the length of the tractor....some have longer sleeper cabs than others. But for average Freightliner with average sleeper cab, towing 53 foot long trailer...could they make that turn ? I suspect not....but maybe...
 
http://design.transportation.org/Documents/TurnRadii,GreenBook2004.pdf

Turning Radius Guidelines for Trucks

My past (20 years ago) experience says "yes", but the trailers have grown by five feet, and the tractors themselves are now most likely "longnose" units instead of cabovers.

There are plenty of guidelines and diagrams on the 'net.

On a tight, but doable turn, with no obstacles on the right side of the road being departed, the driver would:

Before the turn, slide the trailer tandems to the extreme forward position, making the trailer's wheelbase as short as possible (but increasing the "alligator tail" of the trailer), and get the truck/trailer as far to the outside lane as possible.

When making the turn, the driver would start the turn a bit late, which would place the tractor's nose being centered on the opposite curb. At that point, the driver would reverse the steering wheel, and back up the tractor, increasing the tractor/trailer's angle.

[Or is that "reducing" the tractor/trailer's angle :) ]

With the increased "jack-knifing" of the tractor/trailer, and the tandems slid forward, if the turn can be made, it will be made, as long as the "alligator tail" doesn't take out a telephone pole, other vehicles, etc.

It seems your question can be re-phrased as "If both roadways are 28 foot wide, and given the use of both lanes of both roadways, can a modern tractor/trailer make a 90 degree turn?" I say yes, but the above technique may be required.

I started my truck-driving career in Seagrove, NC, where the two lane roads were barely 16 foot wide. I recall seeing the outside tires of my 102 inch wide trailer hanging over the pavement, while going down the road. The front (steer) axle was 8 foot wide, so no problem :ack2: keeping the front wheels on the pavement.
 
The whole point of the topic is the obstacle on the right side...the corner of a metal building.

I could have phrased my answer a bit clearer, sorry about that.

If you are attempting a right turn around a building that is hard up against the roadway, but that's the only obstacle to consider, and:

The roads are 28 foot wide.
There is nothing to the left of the roadways, that an "alligator tail" could strike.
The driver can take up the left lanes while executing the turn.
The driver can slide the tandems forward.
The driver can "jack knife" the vehicle when making the turn.

Then the turn shouldn't be a problem.
 
There is a whole pile of variables here to be considered. First is the wheel base of the tractor, second is length of trailer, third is where is the axle placement on the trailer, forth how competent is the driver. Some guys could go around there all day, others would be screwed the first try. On a diagonal strait out from the corner of the building is the biggest part of the equation, the tractor has to nose as far away from the building as possible to allow for the cut off of the trailer. What about trash bins, empty skids, car parking, these all make a difference as to if and how easily it can be done. From the information you have given, a 53 with the tandems slid ahead should make it. Best put a curb stone even with the eve of the building. If they go up on the curb it will tip the top of the trailer away from the building, if they go over the curb call the insurance adjuster. :codger:
 
I once read that freightliners for some reason have a longer wheelbase than some other truck-tractors - some trucking forum or something. It wasn't about the sleeper cab, it was their their theory of chassis building. I mention this only because you listed freightliner.
 
. What about trash bins, empty skids, car parking, these all make a difference as to if and how easily it can be done.
I thought it obvious one can assume clear passage within the dimensions and one obstruction (corner of building) listed. To mention that trash cans, skids and cars could impede the turn makes about as much sense as mentioning it might not be a good idea to drink diesel fuel.
 
Is the 28' driveway right up against the building? I assume yes or pretty close from your question. How much space between the building and main highway? I'm assuming a little but close. It depends on the radius and the closeness of the building affects whats there or could be there. Assuming a the building close to the road
and 28' road right next to the building I'm going to say it could be done okay. May need a little bit of care but those guys unload cargo in places that would make your jaw drop. Look what the tankers at gas stations do all the time.
 
Is the 28' driveway right up against the building? I assume yes or pretty close from your question. How much space between the building and main highway? I'm assuming a little but close. It depends on the radius and the closeness of the building affects whats there or could be there.
28 feet from back wall of metal building to end/edge of pavement. At the edge of the pavement are planted shrubs so the truck wheels really can't go beyond the pavement edge without irritating the other building occupants about the flattened shrubbery.

As the truck turns right to go around the corner, distance from side wall of building to pavement edge is 46'.


I know I should post a drawing but too busy for that right now.
 
Assuming a 10 wheel horse and 8 wheel 53' trailer with normal king pin placement, it should be okay. I wondered if there was any give right off the road to ease the t-square configuration. that would depend on how close to the road the building is and what grass, plantings, etc. are there. Even a big sleeper cab.... those guys
go out of there way to go slow, make it fit with no damage. The 46' driveway on the other end should be no problem.
 
I'd start my search by finding a recent edition of "Architectural Design Standards" by Ramsay and Sleeper. I've never used an R&S for this type of information, but I do remember getting residential driveway design standards there, and faintly remember seeing the type of stuff you are asking for there. It's been 20 years, though...

Steve
 
I know I should post a drawing but too busy for that right now.

Perhaps a google map screenshot with 90° overhead and the 4 separate N,S,E,W 45° views? Edit out any buildings or stuff easy enough in MS Paint.

I did that for my rigger when I had my machines delivered for my home shop. He saw right away what was involved and confirmed what the pics showed on his pre-delivery site inspection.
 
Doing a quick sketch and using the link that limey posted I would say with reasonable care a 53' trailer and reasonably sized tractor should make it without having to leave the pavement.Bill
 
if this is a regular city type delivery truck you are looking at a day cab,very popular with city type delivery companys.
the highway long haul type may be tight,but doable.
best to get the driver to look at it before he/she attempts it.this is 2 % truck,98 % driver.
 
I think it realy depends on how skilled the driver is, when my machine was delivered on 53 foot trailer with full size truck with queen sleeper so right at that max length. he maid the turn off the township gravel road onto are driveway which is only ten feet wide with a steep bank on the outside of turn radius. so he maid the turn on to a driveway that is about twelve feet wide at the mouth.
A good driver should be able to do this forwards and backwards.
 








 
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