Foundations

Definition of Foundation

• The supporting portion of a structure located below the structure and supported only by soil or rock.

• The purpose of a foundation is to support the structure and distribute the weight of that structure so it settles to the ground evenly rather than unevenly.

What do these 3 Images have in common?

Thegreenelephant.us

www.sl.nsw.gov.au

A STRONG FOOTING• The footing is one major part of the foundation. • Transfers the weight of the building to the earth below• How much soil will settle beneath?• How much weight will go on top?– A house spanning 28’x40’ can weigh 58 tons

• The larger the building, the deeper the foundation penetrates through the weaker soil on the surface to the more stable soils or bedrock beneath.

• A Strong Footing is like an Anchor for walls, holding the stucture down and keeping it stable especially during:– Earthquakes– Strong Wind

www.kpokorny.com

Quick Assignment

• Build a block wall.• Can you tip it over?• Give it a strong footing.• Compare & Contrast.

Point Footings• Pier Foundation• Columns & Beams• Building structure lifted off ground• Minimum ground disturbance• Floor plane is insulated

Pier Foundation

www.timesunion.com

Point / Pier Foundation

http://suffolktimes.timesreview.com/2013/02/38199/new-suffolk-home-rises-anew-after-hurricane-sandy/

Pier Foundation

http://www.treehugger.com/culture/visiting-construct-canada-2007.html

Historic 100 Year Old Structure-Weak soil 20 feet below due to neighboring oil tank failure-

Pile Driver & CraneTemporary beams are drivenDown 38 feet tosupport theIntegrity of the surrounding soil while they perform the soil and groundwater remediation excavation.

http://www.fabco-nj.com/Current_Project_.html

docs.bentley.com

www.atlaspiers.com http://www.oas.org/

Line Wall Foundation• Basement Wall Foundation• Bearing wall• Continuous wall footing= foundation wall• Walls below grade structured to resist earth’s

pressure

www.ukplanservice.co.uk

www.hankeyandbrown.com

Basement Wall Foundation

www.foundationrepairca.com

Line Wall Foundation• Perimeter Wall Foundation• Bearing Wall• Used for crawl space construction• Minimal earth pressure• Most Common Type = T Foundation

Crawl Space

seattle.cbslocal.com

www.aetv.com

www.batticdoor.com

activerain.com

www.grit.com

Foundation with Crawl Space

remodeling-projects.com

PLANE• Ground Slab Foundation• Horizontal Slab• Requires stable & compacted soil• Most common foundation in SoCal is Slab on Grade• Inexpensive• Used when:– Land is flat– No basement is required– Temperatures aren’t below freezing

Slab on Grade

Assignment

• Pick out a foundation for your wall design• Refer to p. 239 in text book• Draft a detail on paper and using ACAD

Retaining Walls

L Type

T Type

Cantilever Type

Mass Type