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Cribbing Shoring Jacking - Residential
- Thread starter DSKENGR
- Start date
Take a look at the CSA - Z240.10.1 standard for Site Preparation, foundation and anchorage of manufactured homes. This standard has some cribbing details for permanent foundations, which could be adapted.
House lifters and mover quite often have the stockpile of cribbing material and use their own tried and true methods for the temporary support of houses.
House lifters and mover quite often have the stockpile of cribbing material and use their own tried and true methods for the temporary support of houses.
I worked with a building mover on a university classroom building to temporarily shore up a 3 story concrete-framed building so that 8 columns could be removed and the crawl space excavated to provide a full-height basement. They were far more prepared to set up the required cribbing and beams than my client would have been. It went much faster than planned and my client was very happy with the results.
I guess it all depends on the whole story - which you haven't really described. Why are you temporarily shoring the house? Are you replacing the foundation?
Ralph
Structures Consulting
Northeast USA
DSKENGR:
The bldg. mover or the G.C. kinda do this stuff by the seat of their pants, with considerable judgement and experience under their belts, plus paid-up liability insur. premiums. And, they (many of them) seem pretty successful at it for the most part. I’ve seen some pretty large structures lifted and/or moved. They don’t have/use some grand bldg. code with an exact factor of safety of 1.6667 or 2.0000 against everything or anything. We as Structural Engineers have to approach these problems from a sort-of reverse engineering standpoint. Codes aren’t much help, but it has to be safe and sufficient, and good engineering judgement is required. We know the bldg. is standing and being supported by columns, beams, bearing walls, exterior walls. We should normally jack and crib at or near these locations, but initially these elements must stay in place. You must study how this load shifting will be taken by immediately adjacent structure. How can you distribute the loads so this can happen? Generally, you have some control over the live loads which are a significant portion of the total loads on the structure. You may well need some temporary support beams btwn. the actual primary structure and your jacking and cribbing. All of this is different in layout for each different structure. While mobile homes may have some cribbing as part of their support system, its location is also well defined by the nature of the structure.
The bldg. mover or the G.C. kinda do this stuff by the seat of their pants, with considerable judgement and experience under their belts, plus paid-up liability insur. premiums. And, they (many of them) seem pretty successful at it for the most part. I’ve seen some pretty large structures lifted and/or moved. They don’t have/use some grand bldg. code with an exact factor of safety of 1.6667 or 2.0000 against everything or anything. We as Structural Engineers have to approach these problems from a sort-of reverse engineering standpoint. Codes aren’t much help, but it has to be safe and sufficient, and good engineering judgement is required. We know the bldg. is standing and being supported by columns, beams, bearing walls, exterior walls. We should normally jack and crib at or near these locations, but initially these elements must stay in place. You must study how this load shifting will be taken by immediately adjacent structure. How can you distribute the loads so this can happen? Generally, you have some control over the live loads which are a significant portion of the total loads on the structure. You may well need some temporary support beams btwn. the actual primary structure and your jacking and cribbing. All of this is different in layout for each different structure. While mobile homes may have some cribbing as part of their support system, its location is also well defined by the nature of the structure.
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