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Attachment C - SCG Soil test and Footing report
Trees: Trees can have a considerable influence over the over the performance of a structures foundation, in particular those founded on
reactive soils (Class S, M, H & E). The trees demand for moisture will change the moisture characteristics of the surrounding soils leading to
localised shrinking and swelling which can exceed the expected soil movement. This can include trees that have been removed prior to
construction. During our Field-testing we have considered trees that existed on or adjacent the site and allowed for them in our
recommendations. We are unable to assess for the potential effects of trees planted after our testing, reference should be made to
“Recommendations for Builders/Owners-Trees” in Appendix D that follows.
Moisture Conditions: The moisture conditions noted within this report are as recorded at the time of our field testing and have been included
in our assessment of the site. Changes to site drainage, the planting of trees or a rising water table can lead to increased levels of moisture
within the soils leading to either an increased classification or design requirements. We must be notified of any increase in moisture conditions.
Also refer to “Recommendations for Builders/Owners – Site Drainage in Appendix D that follows.
Aggressive/Contaminated Soils: This report does not consider the presence of contaminants or sulphates within the tested soils as this is
beyond the scope of this report and our expertise. Engagement of a specialist consultant is advised if this form of assessment is required.
Landslip: This report does not address slope stability issues. A specialist report must be obtained to assess such hazards.
Shrinkage Cracking: Shrinkage cracking of concrete occurs as the initial moisture in the concrete evaporates from mix causing
shrinkage to occur. The cracking as a result of this shrinkage is not a sign of structural failure and is to be expected in most concrete elements
poured on-site. AS2870-2011 states “Shrinkage cracking can be expected in concrete floors”. Unless requested by our client we do not design
concrete floor slabs to be shrinkage crack free.
E. CONSTRUCTION NOTES
E.1 General
We strongly recommend footing excavations be inspected by a qualified person with appropriate experience to
confirm the FOUNDATION MATERIAL and proposed foundation depths are as nominated herein.
Similarly all preparations should be inspected prior to the pouring of concrete by a qualified person with appropriate
experience to confirm that the workmanship and construction conforms with the details and recommendations
contained herein and on associated documentation.
All building dimensions are to be obtained from the approved architectural plans.
All excavations must be totally free of all loose material and debris before pouring. They must be cleaned out so that the concrete is poured
onto undisturbed ground. Tamping and/or watering loose material is not acceptable.
Light watering of prepared surfaces is permitted prior to placing concrete.
All works must be approved by the regulatory authority prior to commencing.
E.2 Tiled Areas
In areas where ceramic floor tiles or brittle coverings alike are specified for ground floor slabs we recommend increasing the size of the slab
mesh by one grade. Use flexible adhesives when affixing tiles and delay the laying for as long as possible (at least 3 months, preferably 6
months) after the slab is poured.
E.3 Concrete
Concrete for footings shall not be less than N20 (20MPa) with 20mm Aggregate and maximum slump of 80mm. Footing concrete must be
vibrated. Concrete for floor slabs shall not be less than N25 (25MPa) with 20mm Aggregate and maximum 80mm slump. Concrete slabs
greater than 100mm thick must be vibrated. In no instance shall concrete be ‘wetted up’ on site during placement.
E.4 Reinforcement
Reinforcement is to comply with the following:
a) Concrete cover to the reinforcement must be 50mm from unprotected ground, 40mm to external exposure, 30mm to the
membrane in contact with the ground, and 30mm to the internal surface.
b) Slab fabric must be lapped by one full panel of fabric plus 25mm so that the two outermost transverse wires of one sheet
overlap two outermost transverse wires of the sheet being lapped. Slab fabric is to be supported on bar chairs placed at
800mm centres.
b) Trench mesh must have all cross wires cut flush with the outer main wires. Trench mesh in slab and edge beams must be
overlapped by the width of the fabric at “T” & “L” intersections. Trench mesh must be spliced, where necessary, by a lap of
500mm.
d) Pre-Fabricated footing cages or reinforcing bars at “T” & “L” intersections are to have a N12 corner tie bars as per the attached
details.
e) The minimum lap length of reinforcing bar is to be 500mm or 40 bar diameters, whichever greater.
E.5 Masonry Articulation
The specifications in this report have been specifically formulated for articulated masonry construction. This usually results lower construction
costs. All masonry walls must have full height articulation at a spacing noted on the first page of this report The articulation joint must separate
the masonry from footing to eaves level at this spacing. Masonry must be supported on each side of the joint in an approved manner to retain
its structural integrity.
Where used, internal masonry walls should be articulated in accordance with the masonry manufacturers requirements for the width and type of
unit used. In no instance should the spacing exceed 4.0m and articulation should always be provided at an abutment with an external wall.
If articulation of masonry is found to be unacceptable, the footing system will require re-designing.
In addition to joints in masonry, articulation is achieved wherever a 10mm (min) separation in masonry from footings to eaves is achieved. For
example, where timber panels are used above and/or below doors and windows.
SCG Consulting Engineers Appendices C to G: Page 2 of 6
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