Minimum upstand on temporary shoring wall 1

[Panars]

When designing a temporary support of excavation, what is the minimum the sheet pile (or lagging) should extend above the ground surface on the top (referred to as the upstand)? I know OSHA in the USA requires a minimum 18" when the ground is sloping down to the top of the sheet pile wall. But is there a minimum requirement for when the ground is level behind the sheet pile? I usually provide 12 inches and a handrail system for fall protection, or 42" so the sheet pile also serves as the handrail. When recently asked about the source of this, I went looking through all my references and couldn't find one. I think I just inherited the 12" from my mentors back in the day.

 

[EireChch]

I usually just detail the sheet pile wall to the to ground level and specify a "handrail / fall protection to be installed by contractor".

While I can see the benefits, I haven't seen a requirement to provide a minimum upstand. This is non US regions.

 

[PEinc]

Extending the sheet piling or soldier beams some minimum distance above the top of retained soil can be needlessly expensive. Raising the wall above grade may cause the wall to be subjected to a greater lateral load than the design. For example, does the sheeting wall need to be designed to keep a vehicle from running off the top of the wall? I usually call for a 42 inch high, fall protection railing with horizontals at 21 and 42 inches plus a kickboard to prevent anything or anyone from sliding or slipping over the top of the wall. FYI, New Jersey DOT calls for the sheeting to extend 3 feet above the top of the retained soils. Sheeting should not also be required to provide maintenance and protection of traffic or resist vehicle impact loads - very expensive!

http://www.PeirceEngineering.com

 

[Panars]

Thank you EireChch and PEinc.