Approved Plan - EXE21-0015

Mr Dean Frith                                                                                       21182-001-Rev0
                                                                                                       28 May 2021

with mass concrete placed to achieve the required depth as necessary. Elsewhere, given the depth to
weathered rock, it will be necessary to support structures on piles. Concrete bored piles are recommended
due to the presence of rock particles within the fill.
Footing design should also account for potential soil reactivity, advised by Ground Drill to be equivalent to
Class H1. Ongoing consolidation settlement of the fill is expected to occur over the long term as the particles
realign to find an equilibrium position. Given the uncontrolled nature of the fill and, settlement might be
expected to be in the order of 1%H up to 2%H, where H is the height of fill. Differential settlements across
the building pad from the cut to fill areas should be expected and accounted for in the design of adjacent
surface or in ground elements (e.g. driveway slab and underground services).

All footings should found such that they are not adversely affected by any adjacent excavations, trenches, or
retaining walls that are not designed to support building loads. Footings should found at least below a plane
extending 1 m horizontally from the base of trenches/excavations/retaining walls, then rising up at 1V:1H, as
illustrated in Text Figure 14.




           Text Figure 14: Footing depth required to minimise the risk of undermining and surcharge loading

Footing bases must be cleaned following mechanical excavation to expose undisturbed materials over the
full base area. A suitably qualified and experienced engineer should inspect the footing excavations to
confirm appropriate foundation materials and cleanliness prior to pouring concrete.

If any soil conditions encountered during construction are found to differ from those noted above, Tectonic
and Ground Drill must be notified immediately and an inspection carried out to determine if changes to
footing design are required.

4.6   Drainage
Adequate site drainage should be installed to ensure that stormwater runoff is directed away from the
building walls and footings (e.g. swales in landscaped areas or grated drains across pavements up slope of
structures). Diversion drainage should be installed above the crests of all cut/fill batters, and toes of all cut
batters. Future landscaping must be carried out to maintain good drainage.

Diversion drainage must be installed above the crest of any cut/fill embankments to divert stormwater away.
All stormwater must be directed by pipes or lined channels to discharge at least 5 m downslope from any
structure or embankment and not upslope of any neighbouring structures/embankments. Surface dissipation,




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