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Footing and Foundation Inspection II. Module five. Module 4, exercise #7 review. 1. What are the general principles regarding the on-site mixing and pouring of concrete?
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Footing and Foundation Inspection II Module five
Module 4, exercise #7 review 1. What are the general principles regarding the on-site mixing and pouring of concrete? - concrete shall be mixed, placed, cured and tested in accordance with CAN3-A438-M, Concrete Construction for Housing and Small Buildings - 9.3.1.1.(1)
Module 4, exercise #7 review 2. What factors govern the minimum depths of foundations? - frost - bearing capacity of soil - water table - desired site drainage design - table 9.12.2.2. - Article 9.12.2.2. - local conditions and designed for lesser depths -9.12.2.2.(5)
Module 4, exercise #7 review 3. What factors should you bear in mind when it comes to backfilling? - brace wall if amount of backfill exceeds the permissible limits - 9.12.3.4.(1) - use clean fill - 9.12.3.3.(1) - avoid damage to wall and tiles - 9.12.3.1.(1) - grade away from building - 9.12.3.2.(1) - drainage layer - 9.14.2.1.
Module 4, exercise #7 review 4. What are the requirements regarding the treatment of the exterior of foundation masonry walls? - 6 mm cement parging and cove at footing - 9.13.2.4.(1) - waterproofing - 9.13.3. - damp-proofing - 9.13.2. - all form ties shall be removed at least flush with the concrete surface - 9.15.6.3.(1) - exterior concrete block above ground shall be tooled jointed, parged or otherwise suitably finished - 9.15.6.2.(1)
Module 4, exercise #7 review 5. What are the requirements regarding drainage tile around foundations? - place outside every foundation which encloses on one side of an interior space (contains a building interior) - 9.14.2.1.(1) - 100 mm (4 inches) diameter - 9.14.3.2.(1) - top of pipe below bottom of slab - 9.14.3.3.(1) - cover top and sides 150 mm - 9.14.3.3.(4) - drain to sewer, drainage ditch or dry well - 9.14.5.1.(1) - use crossovers to allow drainage into sump pit
Module 4, exercise #7 review 7. What general considerations govern the thickness of footings? - loads carried - Table 9.15.3.4. - bearing capacity of soil - Table 9.4.4.1. - high water table - 9.15.3.4.(3) - minimum 100 mm thick - 9.15.3.8.(1) - projection cannot be greater than thickness of footing - 9.15.3.8.(1) - since water table causes width to increase, thickness increases - 9.15.3.4.(3) and 9.15.3.8.(1) - increase footing for masonry veneer over wood frame construction above - 9.15.3.5.(1)(a)
Module 4, exercise #7 review 7. What general considerations govern the thickness of footings? continued - increase footing for masonry construction above - 9.15.3.5.(1)(b) - increase footing for insulated concrete form wall construction above - 9.15.3.5.(1)(c) - increase footing if joists span is more than 4.9 m (16 feet,1 inch) - 9.15.3.4.(2) or design per Section 4.2. - where specified live load exceeds 2.4 kpa (50 psf), design footings per Section 4.2, - 9.15.3.3.(3)
Module 4, exercise #7 review 8. What general considerations govern the thickness of foundation walls? - loads carried - height of soil being retained ( lateral or non-lateral support) - for walls not exceeding 2.5 m in unsupported height the foundation thickness shall conform – 9.15.4.2.(1) and Table 9.15.4.2.A - stable soil and wind loads for reinforced block walls – 9.15.4.2.(4) and Table 9.15.4.2.B - whether insulated concrete forms (ICF) are used – 9.15.4.2.(2)
Module 4, exercise #7 review 9. Under what conditions can it be assumed that foundation walls are laterally supported? - unless the wall around an opening is reinforced, if the window opening is wider than 1.2 m or the total width of the openings in the foundation wall is more than 25% of the length of the wall, the foundation below the window is considered to be laterally unsupported – 9.15.4.3.(3) - if the wall supports solid masonry above -9.15.4.3.(2)(a) - if floor joist are embedded into foundation - 9.15.4.3.(2)(b)
Module 4, exercise #7 review 9. Under what conditions can it be assumed that foundation walls are laterally supported? continued - if a floor system is bolted to the foundation and joists run parallel or perpendicular - 9.15.4.3.(2)(c) - if floor joists are installed as per 9.20.17.5 in flat insulated concrete form foundation walls - 9.15.4.3.(5) - flat insulated concrete forms that support backfill not more than 1.2 m in height, or supported at the footing by a shear key and at the top by the ground floor framing, or are dowelled to the footing with not less than 15M bars spaced not more than 1.2 m on center - 9.15.4.4.(1)
Module 4, exercise #7 review 10. In some instances, a foundation wall is reduced in thickness to permit the installation of floor joists. What requirements govern these instances? - reduced thickness not greater than 350 mm in height and not less than 90 mm thick – 9.15.4.7.(1) -where reduced to permit installation of a masonry exterior facing, the reduced section shall be not less than 90 mm thick and tied to facing material (space between the wall and masonry to be filled with mortar) – 9.15.4.7.(2) and (3)
Module 4, exercise #7 review 11. What requirements govern the use of a wood sill plate on the capping of a hollow unit masonry foundation wall? - anchorage for lateral support : 12.7 mm diameter anchor bolts spaced not greater than 2.4 m, embedded not less than 100mm - 9.23.6.1.(2) and (3) - minimum wood plate size of 38 mm x 89 mm - 9.23.7.1.(1) and 9.15.5.1.(2)(b) - levelling of sill plates - 9.23.7.2.(1) and (2) - capped with concrete – 9.15.5.1.(1) and (2)
Module 4, exercise #7 review 12. Under what circumstances is the anchorage of building frames to foundations not required? - by structural analysis (wind and earth) - 9.23.6.1.(1) - small buildings not more than 4.3 m in width and not more than 1 storey are permitted to be anchored in conformance with the requirements of CSA standards - 9.23.6.3.(1) - garage or carport that is supported on the surface of the ground - 9.35.4.3.(1)
Module 4, exercise #7 review 13. When mixed concrete is delivered to a site, what information should the producer provide the purchaser? - a delivery slip with the following information on it : truck number with time the truck left the batch plant : concrete strength : amount of concrete : type of concrete : temperature of concrete : if any additive : air-entrainment %
Module 4, exercise #7 review 14. What requirements govern the reinforcement of insulated concrete form foundation walls? - for horizontal, vertical and cold joint reinforcement - 9.15.4.5(1) and (2) - for vertical reinforcement – Tables 9.15.4.5.A, 9.15.4.5.B and 9.15.4.5.C
Module Five Houses that have basements require that the foundations be: • structurally sound • resistant to water penetration • comfortable If you build during cold weather you need to understand how freezing causes damage.
Freezing Pressure caused by freezing is • 9 Mpa / °Cup to 200 Mpa @ -20°C • when water freezes its volume increases by 9% • volume increases will depend on the type of soil adjacent and below foundations • considerable volume changes will occur in fine sand, silt and clay
Protection Protection of soil prior to placing concrete will prevent problems • placing concrete on frozen soil will lose heat to the soil and may freeze, resulting in lower strength • protect the soil by covering with • 12” of straw, minimum of 3” insulating blankets • cover with plastic/tarps and introduce mechanical means of heat
Work period Do exercise 1 and 2