CRAWL SPACE FLOOR and POSTS
CRAWL SPACE FLOOR and POSTS
(OP)
I am looking to provide short concrete (or block) columns in a crawl space to support a wooden beam (supporting first floor above). There has been some settlement of the existing block columns which I assume is due to a poor underlying soil condition.
My thought is to construct a 12" reinforced mat slab ontop of the existing floor. This slab would then be the foundation for the short column foundations or even steel posts. Loads are relateively small at possibly 2000# at the column post and I thought this "empirecal" design would work where money is limited to do soil borings, geo-engineering, etc.
Thoughts?
My thought is to construct a 12" reinforced mat slab ontop of the existing floor. This slab would then be the foundation for the short column foundations or even steel posts. Loads are relateively small at possibly 2000# at the column post and I thought this "empirecal" design would work where money is limited to do soil borings, geo-engineering, etc.
Thoughts?





RE: CRAWL SPACE FLOOR and POSTS
Is this not suseptible to freeze and thaw?? If so - you will need to go to frost line.
RE: CRAWL SPACE FLOOR and POSTS
If you use a pier of 8x8x16 block (staggered joint and not just stacked). A pier with these dimensions (24x24) can have a 32x32 unreinfoeced footing is it is 4" thick. If it is 8" thick it can be 40x40 and still unreinforced.
With such a wide pier, the steel is unnecessary because there is no flexure and the thickness takes car of the shear. - Typical construction for residences in many parts of the country and you will have bearing pressures of less than 300 psf. - For 40x40, you be below 200 psf soil bearing.
Dick
Engineer and international traveler interested in construction techniques, problems and proper design.
RE: CRAWL SPACE FLOOR and POSTS
Since there seemed to be such good success with the soils the first time around, this is where I would cut back as well.
RE: CRAWL SPACE FLOOR and POSTS
Now you can patch the cracks.