Apollo Concreting Best Practice

Concrete

Formwork class 5 - ground slab - per m - 200mm to 300mm high
Groove / rebate slab edge formwork - E/O for 150mm rebate to 300mm high slab fwk - per m
Formwork class 5 - ground slab - per m - to 100mm high
High Impact Resistant Polyethylene Film 0.2mm thick Damp proof membrane laid over compacted sub base in strict accordance with AS 2870, ensuring the bottom surface of the concrete slab and footing edges are entirely under laid by the film. The joints are to be overlapped by not less than 200mm to ensure continuity, and to be continuously taped using 50mm duct tape min. Care should be taken to ensure any penetrations by pipes or services are sealed to ensure continuous vapour barrier. All penetrations should also be sealed from termite penetration in accordance with AS 3660.1 – 2014.

BEST PRACTICE NOTE - Although stiffened raft slabs require more formwork than a footing slab, they have a number of advantages over footing slabs, even more so if the footing slab does not incorporate tieing in the slab to the footing with a z-bar steel re enforcement. One of the key advantages of a monolithic slab is the elimination of a control/cold joint forming between the footing and the house slab. Another advantage (if site conditions allow) is the ability to inspect the footing and slab edge once the formwork has been removed. This gives us a chance to add a fluid applied water proofing membrane to the slab and footing edge for added moisture control. Once the sewer lines have been dug and the site is ready to be backfilled and compacted, special care should be taken to ensure the vapour barrier runs hard up against the footing, and up past finished ground level.

Where a slab-on-ground is designed and constructed in accordance with AS 2870 or AS 3600, the area beneath the slab does not require a termite management system other than to the perimeter, service penetrations, slab/footing joints, and control joints. Please note that it is not an acceptable deemed-to-satisfy solution to only provide a hand chemical spray to the soil abutting untied footing/slab joints, service penetrations, and control joints. A concrete slab or footing forming part of a termite management system must: + have all interfaces between the penetrations and slab or footing provided with a termite management system integrated with the slab; and + have all joints, except for tied footing slab construction joints, provided with a termite management system integrated with the slab. (WA Building Commission Industry Bulletin IB 083/2017)

Ground slab / trench mesh - single layer bottom reinforcement - raft - R10 ligature - L11TM3
Ground slab - square mesh reinforcement - raft - per m2 - SL72 
Where brittle floor coverings such as ceramic tiles are to be used, the amount of reinforcement in the slab may need to be increased to control shrinkage cracking. In         these areas we recommened upgrading the mesh to SL92. Alternatively, the laying of tiles (with flexible adhesive) should be delayed for at least 90 days or a flexible bedding mortar used. Construction joints should be designed not to pass through areas to receive a brittle floor finish since this will result in ragged cracks roughly following the line of the joint below. 
Concrete pump / operator - per pour - minimum charge. Concrete at a minimum of 25MPa strength at 28 Days placed, 80mm slump unless specified differently by engineer for pumping (all concrete slabs should be pumped unless chute can directly access pour area, as wheelbarrowing of concrete increases risk of reinforcement mesh not achieving bottom cover due to weight of barrow squashing mesh prior to concrete placement).
Footing beams - strip footings - concrete 25MPa - pump
Slab on ground - concrete 25MPa - pump
Concrete compaction – Immersion vibratorNote: Although slabs up to 100mm aren’t required to be compacted using an immersion vibrator, we highly recommend the use of a vibrator throughout any pour to correctly consolidate the fresh concrete. Due to 80mm slump being a dryer mix, the use of an immersion vibrator has the added advantage of making the concrete easier to work with once vibrated.
Slab finish - steel trowel - hand
Slab finish - steel trowel – power
Concrete curing - covering – DureCore DENSI+ REPELLER air spray applied/Evenrange EVENCURE XDS Water Based Curing compound-  or plastic membrane 100um Note: Once concrete has been finished, the freshly poured and finished slab should be cured for at least 7-Days to ensure it has the opportunity to reach its maximum strength. Although concrete strength is measured at 30 days, the most important time for curing is the first 7 days. That is why it is also very important that edge formwork is kept in place while the slab is curing.

BEST PRACTICE NOTE - When curing the slab with a plastic membrane, white or lightly coloured plastic sheets reflect the rays of the sun and, hence, help to keep concrete relatively cool during hot weather. Black plastic, on the other hand, absorbs heat to a marked extent and may cause unacceptably high concrete temperatures. Its use should be avoided in hot weather, although in cold weather its use may be beneficial in accelerating the rate at which the concrete gains strength. (CCAA DS2006Curing)

With vinyl tiles, timber boards, parquetry, etc it should be noted that it takes about one month for every 25 mm of slab thickness for the moisture content of the concrete to stabilise. An average 100-mm-thick slab should be left for four months prior to the adhesive fixing of this flooring, unless special adhesives are used. (CCAA T49-2003 – Guide to Residential Floors)