Geotch Report December 2021 95141.00.R.001.RevA

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during construction. Should heavy compaction be required, then wall stresses will be well in excess of
Ko and temporary propping should be used.



6.6    Indicative Pavement and Slab-On-Ground

Based on the DCP testing, insitu CBR values for the upper very loose to loose sand (albeit
uncompacted) at the current relative density and moisture conditions is typically less than 3%.

Provided site and subgrade preparation is carried out in accordance with this report and allowing for
minor variations in subgrade type and strength, it is recommended that a design CBR value of 5% or a
modulus of subgrade reaction of 35 kPa/mm be adopted for the upper sands.

Rigid pavements should be designed using a soil modulus of 25 MPa for short term loads and 20 MPa
for long term loads.

For composite subgrades (ie. where imported filling is less than 1m) the Japan Road Association method
of assessing a weighted subgrade strength should be used:

       CBRW = (DF x CBRF0.33 + (1-DF) x CBRS0.33)3

       where:         CBRW = weighted subgrade CBR (%)
                      DF = depth of filling (m)
                      CBRF = CBR of filling material (%)
                      CBRS = CBR of natural subgrade (%)

On-ground building floor slabs (ie. floating slabs) should be detailed so they can accommodate potential
ground movements, including settlements. Differential settlements could be expected to vary across the
site, depending on the floor loads, as well as the thickness and consistency of the near surface soils.
Dowelling of floor slabs will minimise differential movements between adjacent slabs.



6.7    Slope Stability

The site slopes gently from the north-eastern corner at approximately RL 76.5 down at approximately
3o to the south-western corner at approximately RL 72. Inspection of the site by an experienced senior
geotechnical engineer indicates the site to be relatively flat for most parts, with no obvious or significant
scarps, hummocks, visibly disturbed ground or tension cracks which would indicate the presence of
global instability.

Reference to the Noosa Council’s Landslide Hazard Overlay, the site is not identified as being in a
landslide hazard area (refer to Figure 2).




 Geotechnical Investigation, Proposed Youngcare Facility                                   95141.00.R.001.RevA
 32 Viewland Drive, Noosa Heads                                                                 December 2021