07/1571 - Response to Information Request [As Published] · 142007.1571

Project 305-2325
February, 2006 ‘ Page 10

6.3.2 High Level Footings

 

Shallow foundations do not meet the Noosa Shire Council's requirements for scour
protection at this location.

For temporary works such as the support of formwork etc., strip footings between
columns maybe designed for an allowable bearing capacity of 75 kPa in the anticipated
foundation soils (ie. Loose to medium dense sands). Loose sand, either as existing fill,
backfill in overexcavated areas’ or natural, should be compacted to provide the required
allowable bearing capacity. It is recommended that the bearing capacity of the founding
soil be confirmed prior to construction.

6.3.3 Deep Foundations

The choice of suitable deep foundation types should be made from non-vibration piling
methods. Continuous flight auger (CFA) grout or concrete; or conventional bored piles
may be suitable, although the construction of the latter may be problematic in loose sand,
where collapse of the pile hole is likely. Other proprietary non vibration piling methods
may also be suitable. :

It is recommended that the deep foundations used on this project are designed in
accordance with AS 2159-1995 Piling - Design and installation. This code uses the limit
state design method.

The design of a single pile or a pile group must be such that both the geotechnical
strength R*, and the structural strength R*., are greater than or equal to the design action
effect S*, ie.

R‘,>S* and R*, > S*

The design geotechnical strength (R*,) can be calculated as the ultimate geotechnical
strength (Ru) multiplied by the geotechnical strength reduction factor @,. Based on the
field test results, the following ultimate geotechnical strength (Ru,) parameters for the
materials encountered on the site maybe used for preliminary design.

 

- SOM SURVEYS-ENGINEERING

ad.