I did some field work with a smart level. Here are my field notes followed by some comments:
September 4, 2007 7:26 a.m.
7601 E Main ne corner, cross 8% lay notice, door will hold @ notches not heavy
Drive Entrance break 9.2%(6')+9.2%(long), scary, but no scrape
7715 E Main, cross 7.5% back...
Clarification:
8% is not ADA compliant; around ADA spaces, the max slope in any direction is 2%. (2% forward plus 2% cross-wise is 2.8% total and not allowed.)
8% is too steep for a cross slope; car doors won't stay put at that slope.
8% works only as a forward or reverse slope for non-ADA...
I tested the 8% parking space in forward and reverse. I believe it might be noticeably steep to a layman, but the car doors didn't have any trouble at all with it. I think it would be a little excessive as a cross slope. I wouldn't exceed by much 8% going into a parking space.
I couldn't...
We have an parking space in front of our office that slopes upward 8%. I don't think there is any door-slamming problem since the 8% is in the forward direction. It may be that in the cross direction it would be a problem. I will have to take our smart level out and run a few tests around...
If you are too cheap to get AutoTURN (like I am) and want to support the Free Software concept, you could try my TURN.LSP to trace turning paths on weaving sites. It has had a lot of interest and one lone donation in the past few years. It is at www.hawsedc.com under Free Software, or just...
Do you mean turning templates? I put some up at my site along with a turning path AutoLISP program a few years ago. It may help you out.
www.hawsedc.com/gnu
Tom Haws
WB40 and WB50 are standard vehicles used for design. If you go to www.hawsedc.com/gnu/turn.php (my site), you will see it explained with the dimensions of those AASHTO vehicles given.