Slope Stability - lindsays

5.   SITE CLASSIFICATION AND TARGET STRATA

     Based on the findings of the site investigation and the footing system design proposed
     on the client supplied information, the classification of the site is considered to conform
     to: -

                                      CLASS " P "
         This classification is due to poor bearing capacity of the existing soil
          and the presence of many trees within the proposed building zone.
          However, if this was not the case the soil type and reactivity would
                        be comparable to that of a CLASS " S ".

     in accordance with Australian Standard 2870-2011, 'Residential Slabs and Footings,
     Construction'.

     The target stratum where 100kpa of allowable bearing capacity is attained by a suitable
     founding material is the medium dense SAND which occurs at a depth of 1700mm
     from the existing ground level at location BH1 and a depth of 1500mm from the
     existing ground level at location BH2. Any fill placed over the existing ground shall be
     piered through the fill into the existing material. Further note that the placement of
     reactive material as fill may change the site’s classification.



6.   FOOTING SYSTEM DESIGN

     The footing system shall be designed to conform to the performance limits stated in AS
     2870 – 2011 and reprinted in the C.S.I.R.O.'s Publication 10/91, 'Guide to Home
     Owners on Foundation Maintenance and Footing Performance', a copy of which
     attached to this report. It should be noted that footings designed in accordance with
     AS2870-2011 does not guarantee no movement of footings, shrinkage cracking or other
     damage to the building.

     Foundation preparation and footing construction shall be in accordance AS 2870 -2011
     and AS 3798-1990 'Guidelines on Earthworks for Commercial and Residential
     Developments'.

     Where necessary, subsoil drainage shall be incorporated in the construction of the
     building to ensure that subsurface water is properly drained away from the footings.

     Potential seepage or subsoil drainage problems cannot always be recognised from the
     results of a site investigation. Problems with respect to subsurface water flow or
     seepage may not be evident until after the site has been subject to the first significant
     wet period.

     After construction of the footing system the ground surface around the residence shall
     be sloped away from the footings at a fall of 1 in 20 minimum for a distance of 2000
     mm.


7.   ARTICULATION

     It is recommended that masonry walls on Class M, H, E and P sites be articulated at all
     or some openings. Articulation joints shall be constructed in accordance with the
     Cement and Concrete Association's Publication 'TN61 - Articulated Walling'.