During a large pour, what should be included in batch records for all suppliers?

• A. List of workers.
• B. Mix designs, batch records for all suppliers, and sampling times.
• C. Weather forecast only.
• D. Site safety plan.

Answer: (B)

For a large pour, the documentation you keep on batch records must provide a complete trail from materials to test results. The most comprehensive and useful record includes the mix designs, batch records for all suppliers, and the times when samples were taken.

Mix designs show the exact proportions and material properties of the concrete you intend to place—cement type and content, supplementary cementitious materials, aggregates, water, and admixtures, plus target slump, air content, and strength. Keeping the mix design for the actual pour ensures the delivered concrete matches the specification and gives you a reference point if test results deviate.

Including batch records for all suppliers is essential because a large pour often uses multiple sources for cement, fly ash or slag, aggregates, and admixtures. Each supplier’s batch information—lot numbers, quantities delivered, and delivery times—lets you trace every portion of the pour back to its material source. This traceability is critical for quality control, troubleshooting, and accountability if any test results or field observations raise questions.

Documenting sampling times ties the testing to the exact material batches that were placed. Recording when samples were collected, from which batch, and at what stage of the pour ensures that test results (like slump, air content, and strength) correspond to the correct materials and portions of the pour. It also helps verify compliance with the project’s sampling plan and allows scheduling adjustments if issues arise.

Weather, safety plans, or lists of workers alone do not provide the necessary traceability and linkage between materials and test results for a large pour. Weather can influence workability and curing, and safety plans address risk management, but those items do not substitute for the material-focused accountability captured in batch records.