Need Help - Vehicular - Pedestrian Guardrails

[CPENG78]

Hello All,
I have an elevated pad (5 ft max at high end) with a perimeter retaining wall where temporary buildings will be installed. Eventually these buildings will be removed and the pad will be used as a parking lot. In areas where the grade differential exceeds 30" I am definitely installing a pedestrian handrail. However, the question arises for the ultimate condition to protect vehicles from driving over. Would someone please point me to a standard that would be used as to which grade differential calls for a vehicle guardrail? This is on private property but I acknowledge it will also depend on the level of risk that the owner and or engineer would take as to the extent of guardrail to be installed?

This project is in California, I am looking into the Cal Trans highway design manual at the moment however it feels like what Caltrans might show may be a bit of overkill for this situation. Your thoughts or input is certainly appreciated.

 

[gbam]

CPENG78 - we encountered something similar here in AZ. There was no policy or standard for this scenario. We evaluated the use of a reinforced concrete high wall (3 feet high) behind the parking stops, designed for impact from truck. This wall seperated the parking area from the pedestrian area and then we used standard handrail. It was a good concept, although too costly for the developer. They opted for a heavier 3-tube "barricade" rail fence designed for impact.

 

[bridgebuster]

Perhaps the AASHTO Roadside Design Guide or Highway Safety Manual has some guidance. However, you answered your question. Intuition tells you to do something. Since some people don't believe in intuition just say common sense or better yet engineering judgment tells you a railing is needed.