| General
All materials required for the successful completion of the works are to be provided by the Supplier.
Subgrade Preparation
The subgrade shall be formed at the required depth below the finished surface levels shown on the Drawings. The subgrade shall be neatly excavated to form a bed for the concrete, and shall be thoroughly scraped and cleaned. Soil foundation shall, as far as possible, be excavated neatly from the solid material to coincide with the under-surface of the concrete.
All soft, yielding or other unsuitable material shall be replaced with sound material in accordance with the drawings, and the subgrade shall be compacted to provide a minimum relative compaction of 98% as determined by AS 1289. If the subgrade is dry it shall be sprinkled with as much water as it will readily absorb, before the concrete is placed.
Formwork
Formwork shall be provided to produce hardened concrete to the lines, levels and shapes shown on the Drawings. It shall have adequate strength to carry all applied loads, including the pressure of fresh concrete, vibration loads, weight of workers and equipment, without loss of shape. Forms shall be mortar tight and designed to allow removal without risk of damage to the completed structure.
Formwork material used shall be sound and suitable for the purpose intended and surface finish specified.
Steel Reinforcement for Concrete
Steel reinforcement shall comply with the requirements of the provided drawings.
The type and size of bars is detailed on the Drawings.
Reinforcement shall be formed to the dimensions and shapes shown on the Drawings.
Reinforcement shall be placed as shown on the Drawings and shall be securely held by blocking from the forms, by supporting on concrete or plastic chairs, or metal hangers, and by wiring together at all intersections detailed in the drawings.
Steel shall not be supported on metal supports which extend to the surface of concrete, on wooden supports, or on pieces of coarse aggregate. Reinforcement shall have the minimum cover shown on the Drawings.
Hold Point
A single hold point will be enforced once reinforcing is in place prior to the concrete pour. Photographic evidence is to be submitted by the supplier to the Customer or their representative for assessment. No pouring of concrete can occur until the Hold Point is released by the Customer.
Photographs may be submitted via email or text message.
Concrete
Concrete shall not be placed until the excavations, forms and reinforcement have been inspected and approved by the Customer. All excavations and forms shall be cleaned of debris and loose material and unless otherwise approved by the Superintendent, excavations shall be free of water while concrete is being placed. All concrete shall be placed in the presence of the Superintendent.
Concrete shall be handled from the mixer to the place of final deposit as rapidly as possible by methods which shall prevent segregation or loss of ingredients. It shall be placed so as not to displace steel reinforcing, steel stubs and cleats or formwork.
Concrete shall be thoroughly compacted by means of high speed mechanical vibrators.
The Superintendent may stop the placing of concrete, or may order that concrete operations shall not commence on account of wet weather or other causes which may prevent the satisfactory placing of concrete.
The concrete shall be mixed, transported, placed and compacted as rapidly as possible
All concrete surfaces shall be true and free from stone pockets, depressions or projections beyond the surface.
Care shall be exercised when removing forms. All surfaces shall be free from voids, honeycombing, or other large blemishes.
Copies of all records and reports required shall be forwarded to the Superintendent within 48 hours of completion.
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