Elements and Performance Criteria

This competency unit includes:
placement of reinforcing, placement and stressing of strands
compaction using form vibrators, vibrating tables and immersion vibrators as appropriate to the enterprise
curing by water, steam, membrane or other heat sources as appropriate to the enterprise
specialised formwork techniques which could involve polystyrene blocks to lighten heavy products
deflected strands
jigging reinforcement
end block reinforcement
welding.

Typical problems include:
slippage, breaking of tensioned strands
mould leakage
compaction in areas with high reinforcement content (end blocks, haunches, etc)
compact product with tight bends/clearances
polystyrene blocks (which may be used in formwork to lighten products) may float to surface on vibration
polystyrene blocks may move sideways undetected, reducing wall thickness
adjustment to take account of variables such as weather
variations in cement/water ratio.
This competency includes the operation of all ancillary equipment and the operation of plant using programmable logic controllers (PLCs) where appropriate.
All operations are performed in accordance with standard procedures and work instructions.

OHS
All operations are subject to stringent OHS requirements and these must not be compromised at any time. Where there is an apparent conflict between performance criteria and OHS requirements, the OHS requirements take precedence.

Assessment context and methods
Competence in this unit may be assessed by observation over time on an operating plant. Where this is done, the timeframe must allow for adequate assessment of operation under all normal and a range of abnormal conditions. Where this is not practical, additional assessment techniques must be used.
Competence may also be assessed by use of a suitable simulation and/or a range of case studies/scenarios. A combination of these techniques should be used to ensure the competency is adequately assessed.
In all cases it is expected that the practical assessment will be supported by targeted questioning to assess the underpinning knowledge. Questioning will be undertaken in such a manner as is appropriate to the language and literacy levels of the operator and reflecting the requirements of the competency.

Critical aspects
It is essential that the process be understood and that the importance of critical material properties and design characteristics is known. Competence must be demonstrated in the ability to recognise and analyse potential situations requiring action and then in implementing appropriate corrective action.

Consistent performance should be demonstrated. In particular look to see that:

products are made consistently in minimum time and with minimum patching
finishing is within specification/example
good OHS practice is used consistently.
Competence must be demonstrated in the operation of all ancillary equipment to the level required for this competency unit.

Resource implications
Resources required include suitable access to an operating plant or equipment which allows for appropriate and realistic simulation. A bank of case studies/scenarios will also be required where these form part of the assessment method. Questioning may take place either in the workplace, or in an adjacent, quiet facility such as an office or lunch room. No other special resources are required.

Essential knowledge and enterprise requirements
Knowledge and understanding of the process sufficient to recognise potential problems and take appropriate action.
Knowledge of the enterprise's standard procedures and work instructions and relevant regulatory requirements along with the ability to implement them within appropriate time constraints and in a manner relevant to the operation of the process.

Competence includes the ability to:


apply and/or explain:

effect of water-cement ratio on product
importance of vibration on compaction
required concrete cover of reinforcing
hazards from critical stages of prestressing reinforcement (placement, stressing, destressing, cutting, etc)
concrete sampling and testing procedures
nonconformance procedures

distinguish between causes of faults such as:

concrete
vibration
aggregate size
reinforcing design/placement
setting/curing time/rate
as is relevant to the practical operation of the process.

Communicating ideas and information
(2)

Collecting analysing and organising information
(2)

Planning and organising activities
(2)

Working with others and in teams
(2)

Using mathematical ideas and techniques
(2)

Solving problems
(2)

Using technology
(2)