This month the Technical Director’s Message will revisit the ongoing Interior Slab Mix Collection research project. Hundreds of newer IL cement mixes and historic I/II cement-based mixes are still needed for an artificial intelligence (AI) platform to look for patterns between the I/II and IL mixes that are performing well. The guidelines are meant to help contractors transition to successful IL mixes and provide talking points to collaborate with ready mixes producers on optimizing mixes. Collaboration is one of the strengths of ASCC, let’s work together on solutions to this complex challenge. Some members have stated they are not placing interior non-air slabs. Regional ASCC advocates are also needed to talk with local ready mixed producers and ask for 2017-2022 interior SOG mix designs, prior to the IL rollout. Every ready producer will have numerous mixes like this.

Surveys collected in 2023 indicate many concrete contractors have had issues with interior slab mixes using ASTM C595 Type IL cement, while many others (~50%) report no new issues. Contractors requested through ASCC and ACI meetings that there be a project to collect concrete mixes and cement mill certificates from across the country to attempt to discover what is fundamentally different between the mixes performing well vs those that are not. This investigation will be across all lower 48 states and 8 NRMCA regions with a goal of 1,000 mixes collected (600 IL and 400 I/II or II/V). Analysis will be performed by an artificial intelligence, AI, platform and validated by industry experts. A report to follow with a list of regional strong and weak correlations of changes likely to help improve the mix and what is not likely to improve the mix performance. Note that an expert SOG consultant will be better at looking at one specific mix than any analysis looking at trends in hundreds of mixes. ASCC can provide a list of expert consultants if needed.

The appeal was sent to ~300 ASCC contractors and ACI 302 members requesting SOG mixes. In addition to 2023 - 2024 mixes with IL cement the request was made for mixes with I/II (or II/V) cement concrete, to establish a baseline for the AI of state of the industry prior to the wide production of IL cement.

If you would like to participate, please send submittals to mhernandez@ascconline.org  Please send: 3000 to 5000 psi, non-air entrained, normal weight concrete slab mixes. The information needed is:

• Mix Proportions

• Cement Mill Certs

• Aggregate Gradations

• Admixture names

If you submit a IL mix you will also be asked to fill out a survey of up to six questions on its performance using this link: Mix Study Survey