Wheel Stop Design References? 1

[RDR89]

HI all,

Was reaching out to see if anyone had any references on design of concrete/precast wheel stops? I know they are typically standard designs but these have to be custom due to height restrictions and loading (70K).

 

[DoubleStud]

When I was in precast industry we did not design it really. We just put enough steel for shipping and handling. But they are for small passenger vehicles at common parking lots.

 

[RDR89]

@DoubleStud yea this would be for much heavier commercial vehicles. I am not sure if looking at the stops as a continuous beam between the dowels that connect them to the subgrade is a close enough assumption.

 

[bridgebuster]

70K ????? That's not a wheel stop; that's a traffic barrier. The Federal Transit administration, DoD, AASHTO, & FHWA have design manuals for physical security. Maybe look at some state DOT concrete barriers as well.

 

[RDR89]

@bridgebuster haha! Yea I have some clarifications into the client to confirm whether the load is accurate but that is what I was given so far. Thanks for the input!

 

[bridgebuster]

Please Keep us informed.

 

[GC_Hopi]

I am curious too when I think of a wheel stop I think of the below. It does not really "stop" a vehicle since its simply a speed bump. Sounds like a barrier or guardrail... SELECTION AND APPLICATION OF
VEHICLE BARRIERS - UFC 4-022-02 could be a reference.

 

[RDR89]

@GC_Hopi, I understand what you're saying. But there are instances where cars will "bump" into the stops. I am not sure how to quantify the magnitude of the load that is imparted or what guidance there is on it. Will check out your reference as well, thanks!

 

[GC_Hopi]

I believe the design of wheel stops on the market is just based on historical performance. They are pretty low cost 30 to 90 dollars so they are generally replaced if wear and tear happens.

 

[GC_Hopi]

You can get a couple industrial ones and try them out. It says they have a 3 year warranty.

Link

 

[bridgebuster]

@RDR89, two ways to find out how much load is imparted: 1. Build something and crash test it; 2) model the design with Ansys LS-Dyna. Both are easier said than done but I can put you in touch with someone for option 2. It’s not cheap. A check of a small bollard was going to run us north of $25k and that was 5 years ago. (Sorry I’m typing on a moving bus)

The FTA has a good manual on physical security. They have test results for different vehicles, don’t think they went to 70k. Don’t recall high high the UFC manuals go.

AASHTO LRFD bridge specs has a design example for bridge mounted concrete barrier and test data for TL-5, which is approximately what you’re looking at.

 

[Smoulder]

No reference but mining industry uses half truck weight for the dump wheel stops. 3-400 tonne trucks reverse slowly and hit the bump every time to make sure they're tipping in the right place. Are you talking slow bumps or crashes?

 

[LittleInch]

It's the max height vs wheel diameter vs how low is the vehicle superstructure?

Plus anticipated speed.

Anything less than 0.5 x wheel diameter could end up being run over at anything much above 5 mph.

there are loads of rubber wheel stops about, all about 4" high from what I can see.

Have you thought about pipe or trees just pinned to the ground?

Something like this instead?

https://www.polymax.co.uk/site-safety/kerbs/hgv-wheel-stops

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[RDR89]

No they want precast. I have seen a ton of standard precast details when I do a high level online search but no real guidance on their design. I looked through the references that Bridgebuster and GC_Hopi sent but I don’t think we’re trying to completely stop the vehicle. From the layout that the client sent it looks like they just want them for parking spots next to EV chargers for the trucks.

And Bridgebuster I did get clarification on the load - the entire truck weight is ~66K with the back axle ~39K. Our sales rep had communicated the information as 70K in the back axles initially (hence the initial post), so glad I got that clarification. The truck is an EV truck so non-standard. Still waiting on info about the tires to determine the pressure.

I guess my question still remains… is this just designed as a beam between the dowels going into the asphalt/subgrade? To GC_Hopi’s point, they all seem to be based on existing data so I’m not sure how to go about designing something different.

 

[bridgebuster]

Sounds like you want to install a shallow height wall or a grade beam that projects slightly above grade. The trick is to determine the force going into the
"wheel stop", F=ma. If you build a wall you could assume the horizontal reinforcement is the main rebar and consider the passive pressure as resisting the lateral force.

The attached may help.

 

[bridgebuster]

this might be useful as well