Vehicle Barrier Design

[slickdeals]

Greetings,
I have a question pertaining to vehicle barrier design for buildings. IBC requires that these barriers be designed for a load of 6000# acting at a height of 18". What is the width transverse to the load that you assume this load to be distributed? I know AASHTO allows you to assume a 5 foot width transverse to the load. Do you use the same assumption to design the wall and the anchors that support it? I have found no such provision in IBC. How do you design your vehicle barriers?

Thanks

 

[msquared48]

I design them as 4' diameter concrete planters and stagger the spacing so that people can pass through, but vehicles cannot.

Mike McCann
McCann Engineering

 

[slickdeals]

"I design them as 4' diameter concrete planters "

as in stub columns?

 

[miecz]

I don't think you can take a 5 foot distribution width specified for concrete parapet and barrier walls in AASHTO 2.7.1.3.6. I believe the distribution assumes a truck load near the top of a 32 inches high barrier (See Figure 2.7.4B). It's not stated anywhere, but I believe the 5 foot distribution width assumes a 45 degree spread from the top of the barrier. With a 45 degree distribution, your distribution width is 3 feet.

 

[shin25]

I agree with miecz. The load is assumed to travel at 45 degree angle from the point of impact.

 

[slickdeals]

I guess I can then design my crash wall as a 3' wide beam resisting the loads?

 

[miecz]

yes

 

[msquared48]

Yes, solid filled stub columns on large spread footings with a planter at the top.

Mike McCann
McCann Engineering