06/1168 - Change a Development Approval [As Published] · 132006.1168.02

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Adding crushed ice to replace mixing water (in part) or chilling the water;

Injection of liquid nitrogen into the mixer.

2. At the Site

» Cooling the formwork by dampening with water sprays;

» Shading the work areas;

» Erecting wind breaks;

» Minimising the time for placing and finishing;

» Use of evaporation retarding curing oil.

Special attention shall be paid to providing early curing for hot weather concreting operations.

The concrete shall have a temperature not higher than 35°C when placed, which shall be achieved by
using the above precautions if necessary.

6.8 Compacting of Concrete

Concrete during placing shall be thoroughly compacted using immersion vibrators of approved type and
such spading tools or measures as necessary to ensure the elimination of segregation and voids and to
compact the concrete around the reinforcement and into the corners of the forms.

The Contractor shall keep in hand on site one spare vibrator for emergency use.

Depth and rate of placement of concrete shall be such that preceding layers shall remain in a soft and
plastic state when covered by each succeeding lift or layer. Vibration and other compaction measures
shall extend through full depth of each layer of fresh concrete and into the preceding layer to completely
compact successive batches and merge them with each other. The vibrator shall not be allowed to
penetrate into partially hardened concrete or to disturb reinforcement.

Vibration shall not continue for more than 30 seconds in one position. If pools of grout, water or laitance
form readily during vibration the concrete mixture shall be modified as ordered by the Superintendent.

6.9 Construction Joints

Construction joints shall be made where shown on the drawings or in locations approved by the
Superintendent. In general, concrete pours shall be made in as large a section as possible to minimise
the number of construction joints required. Where stoppage of concreting operations occurs for any
treason, construction joints shall be placed either horizontally or vertically as needed, provided with keys
to resist shear, and dowels to develop bond as directed by the Superintendent. All reinforcement shall
continue through construction joints.

Before depositing new concrete against concrete which has hardened, the forms shall be re-tightened
and the surface of the old concrete shall have all loose projecting aggregate, laitance, and other
objectionable substances removed, shall be roughened by scabbling or other suitable means as required
by the Superintendent, and shall be thoroughly washed and saturated with clean water. After excess

41/22382/11840 Girraween Sports Precinct 38
Earthworks Package