CSA - Concrete Specialist

CSA - Concrete Specialist
Occasional site visits – once every 6 weeks
Contract - Inside IR35

Specification
Review the existing Technical Specification for the works, and provide any feedback on Section 7 ‘Reinforced Concrete’ which you believe may need to be taken into account. Once reviewed, this specification sets the baseline for which the subsequent activities shall assess compliance.
Constituent Material Qualification
Review, comment and accept the Contractors Proposal/Structural Concrete Constituent Material Supply Report. The constituent material qualification tests for aggregates are listed in Table 4.
Review, comment and accept the Contractors Proposal/Concrete Validity study on the target concrete mix design.
Sensitivity Study
Review, comment and accept the Contractors Proposal/Sensitivity study to evaluate the sensitivity of the concrete to accidental variations in batch masses.
Review, comment and accept the Contractors Proposal to undertake tests to reflect these lower tolerances where the batching tolerances for the plant are significantly lower than those indicated in BS EN 206 (if applicable).
Review, comment and accept the Contractors Proposal/Admixtures used in the validity study, including infrared spectrophotometry results (completed in accordance with a procedure written by the contractor and submitted for information). The analysis is to be carried out by an independent organisation.
Review, comment and accept the Contractors Proposal/Additional tests for qualification of a self-compacting concrete (if applicable).

Concrete Production Suitability Tests
Final suitability testing confirms the performance of the concrete during construction operations. No concrete mix design shall be cast in place without undergoing an initial suitability test (concrete shall be produced using the proposed production plant and replicated site conditions as closely as feasible). No change shall be made to the target concrete mix design from the qualification test except for the admixture dosage. Suitability tests as Table 6.
Precautions against thermal cracking
Review, comment and accept the Contractors Proposal to ensure the maximum temperature at any point in the concrete does not exceed 60ºC
Review, comment and accept the Contractors Proposal to ensure the maximum temperature differential between the centre of the concrete pour and the surface of the pour shall not exceed the limit set down in Table 13.
Review, comment and accept the Contractors Proposal/Report that summarises:
i. Anticipated temperature and strength profiles of the concrete.
ii. Anticipated temperature differentials of the concrete considering.
Ambient temperatures.
Pour thickness.
iii. Actions that will be taken to control peak temperatures and/or differentials.
iv. Methodology for monitoring in-situ concrete temperatures, which as a minimum should include;
Typical location of sensors (two sensors to be used at central locations in initial pours in case of failure).
Automatic logging of sensor output every 30 minutes.

Production Conformity Control
Sampled review (All records for the initial Class 1 pour, then reducing to 5% sampled check throughout the construction programme) on the conformity control submissions as per Table 7.

Confirm that Lifetime Quality Records are being compiled as per the ITP / Quality Plan. Progressive checks to be completed on the records at monthly intervals.
Review, comment and accept the Contractors Proposal/methodology for controlling maximum temperature and restricting temperature differentials in the concrete and controlling Early Age thermal cracking in accordance with CIRIA Report C766. Identifying any concrete pours at risk of excessive heat development and the measures to mitigate this.
Review, comment and accept the Contractors Proposal/Method statement for the production, transport, placing, compaction (with particular reference to slender sections) and curing of concrete giving details of the proposed plant, equipment, methods, products and personnel.
Review, comment and accept the Contractors Proposal/Quality Control Plan and Sampling and testing plan for the concrete from production to the completed element.
Review, comment and accept the Contractors Proposal/Method statement for making good to defects including details of proposed materials.
Review, comment and accept the Contractors Proposal/Datasheets provided for all admixtures proposed for use in concrete.
Review, comment and accept the Contractors Proposal/Proposed sequence of pours indicating the position and nature of joints where appropriate.