reconciling IBC and FEMA pile requirements
reconciling IBC and FEMA pile requirements
(OP)
Hi all,
Section 1810.2.2 of the IBC stipulates that piles must be braced for stability by providing grade beams at ~ orthogonal directions to the pile cap/gb intersections - i.e. free-standing piles are not allowed - exception 1 appears to require that the pile is embedded in soil over its entire length. Prior to building houses on elevated piles, this would have been my approach. I'm now working on single family residences in VE and coastal A zones. Going through the FEMA P55 coastal construction manual, the use of grade beams appears counter indicated as it induces greater scour depths. In my particular case, the piles are augercast (and CIP above grade). I'm at odds about how to proceed. Would the answer be to cast concrete beams at the top of the piles above grade to create a portal? This might be prohibitively expensive... Any and all input appreciated.
Section 1810.2.2 of the IBC stipulates that piles must be braced for stability by providing grade beams at ~ orthogonal directions to the pile cap/gb intersections - i.e. free-standing piles are not allowed - exception 1 appears to require that the pile is embedded in soil over its entire length. Prior to building houses on elevated piles, this would have been my approach. I'm now working on single family residences in VE and coastal A zones. Going through the FEMA P55 coastal construction manual, the use of grade beams appears counter indicated as it induces greater scour depths. In my particular case, the piles are augercast (and CIP above grade). I'm at odds about how to proceed. Would the answer be to cast concrete beams at the top of the piles above grade to create a portal? This might be prohibitively expensive... Any and all input appreciated.
Talk To Other Members
RE: reconciling IBC and FEMA pile requirements
While this is a seismic requirement, I do not recommend skipping the good practice of interconnecting (independent) piles below a light-framed structure - even in non-seismic zones. The horizontal tie forces in the floor members are undefined unless there are stiff and strong ties.
RE: reconciling IBC and FEMA pile requirements
RE: reconciling IBC and FEMA pile requirements
Or 1810.1.4 might consider these a special type of deep foundation.
RE: reconciling IBC and FEMA pile requirements
This also seems to meet the intent of tying piles together to prevent spreading in earthquake scenarios.
Is the concrete to wood strength and stiffness differential making it so that you can't effectively consider your superstructure as an effective bracing/diaphragm element?
RE: reconciling IBC and FEMA pile requirements
Are your augercast piles deep enough and reinforced for bending alone?
RE: reconciling IBC and FEMA pile requirements