2008/0169 Response to information request - 71 Seaview Tce Sunshine Beach · 132008.169

                                                                     TOO _ INSULTING


7.0   Pool/Terrace/Bedroom 5 Building

      7.1   General Structural System

            The Poolfi errace Building is a tiered two-storey reinforced concrete
            structure with a reinforced concrete contiguous piled retaining wall system
            to support excavations of approximately 2.5m maximum. A mixture of
            grout replacement piles and concrete-filled galvanised screw piles are
            proposed to support vertical loads, and a range of raking galvanised screw
            piles or permanent tie-back anchors are intended to provide horizontal
            stability to the foundation by acting in tension, and tying the foundations
            back into the dense sands below the hill above,

            Structural System Summary:

            •    600mm diameter contiguous CFA piles retaining walls, founded
                 approximately 8m below excavation level to provide vertical capacity
                 and passive resistance to horizontal soil pressures
            •    Isolated 600mm diameter CFA concrete piles
            •    Screw piles ranging from 50-80T to support column loads
            •    Raking tension screw piles installed back into the hill, to provide
                 horizontal resistance to soil loads, wind and earthquake loads
            •    Reinforced concrete ground beams and slabs will be used to provide
                 adequate permanent horizontal "strutting" of retaining walls and
                 rotational stability to pile/slab/upper column connections, and resist
                 moments due to pile eccentricity
            •    Sub-floor areas will be drained to relieve any potential build-up of
                 ground water pressure
            •    Areas behind contiguous piled walls will be fully drained by using
                 drilled-in steel "wick" drains at about 4m centres, connected through
                 the base of the wall and discharged appropriately in separate drains
                 from internal cavity drainage
            •    Upper structure comprises reinforced concrete columns, walls and a
                 cantilevered beam/slab system to support the pool
            •    Roof terrace spans vary, requiring 2000mm deep cambered
                 cantilevered concrete beams to support pool
            •    Roof terrace slab will need a high grade trafficable waterproof
                 membrane or a trafficable slab may be considered over an insulated
                 waterproofing layer on the structural slab
             •   Garden terrace area will be generally constructed on screw piles,
                  ground beams and suspended slabs over voids to avoid imposing
                  additional soil loads to the steep sandy slopes
             •    The pool will be constructed of reinforced concrete poured in one
                  continuous pour. It will be entirely independent of the supporting
                  reinforced concrete super structure which must be completely
                  waterproofed and provided with a drained cavity. This building will
                  be supported on galvanised screw piles penetrating at least 5m below
                  the 27° slip line, projected from the base of the slope.




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