Tractor Trailer Driveway Design Specifications

You should try for about 3ft from the greenhouse to start a 10ft wide drive down the to new greenhouse pad. This drive should go up straight about 60 ft from the corner of the old greenhouse. (think of it as being from the center of the tandems to the nose of the tractor). You can reduce the 60 if you widen the distance from the greenhouse side (the 3 ft).

 

You made me go out and measure, lol.

My road is 24' wide. My driveway entrance is 25' wide at a 35 degree angle. I used a speed square to estimate the angle.

It's very tight, but I backed in a many of times with a 53' trailer and 70" sleeper.

 

Whew, good thing its not a blind back. The Driver can't see anything out the right side mirror when backing and turning at the same time. Know what I mean? To answer your question, why not gravel a small area at first and observe the tracks left by the tractor trailer. You can minimize your area quickly this way. Then you can procede with the expensive concrete and steel.

 

Going out on a limb here.
First make the top of the sketch North then the right East and so on'

Is the truck you describe the only one going into the dock? Most trucks now (Freightliners with sleeper and 53' trailer) are usually 74' long on average. I would make the drive big enough to handle the maximum length as it could happen!
Remember what looks good on paper does not always look good in real life.

On your sketch at the mark of "how far to cut here" from the dock to that point keep it straight then a gentle curve then straight to the road. Remember that the trailer turns inside of the tractor so the point where the truck makes the left curve should be at least 37'- 40' north of the corner of the existing building
BUT:
Which way will they be turning when leaving? Looking at the layout I'm guessing that they are coming from the right Out of the east then leaving to go back east the trailer is going into the ditch if there is one or sinking into the ground when wet. That will be an extremely hard right turn out of the drive. I guess they have to always turn left or west heading out.

IMHO i would just get a permit from the county or state to widen the driveway and just make this a parking lot instead of a drive way or call it a really wide driveway and just go straight from the dock to the street. You'll have to pay for the DOT to place 32" drainage pipe under the drive way but as a business and to keep away from any frivolous law suits like the driver pulling out in front of someone coming from the right as it looks like you are in a curve and those things happen the wider driveway will help the trucks have a better view from the right and make it easier for traffic both inbound and outbound have easier access to the street.

Get a driver with a sleeper and 53' trl and empty and fairly dry and have him back into the spot and have him show you how hart that right turn out is going to be.

Remember, if a tow truck is called to get one drug out of the ditch that's going to be at least a $500 bill. Spend the money for a wider driveway.