What changed
Regional material screen
Generic Type IL cement, a local fine-sand supply family and a separate Class F fly-ash family were screened against the same pinned CEMFORGE model. Exact local lots, chemistry, gradation, price and delivery remain unresolved.
Engineering context
Idaho Falls adds a published 47.1 psf ground snow load, 30-inch frost depth, Exposure C wind basis, Seismic Design Category D absent better geotechnical information, and a materially drier planning climate.
A small, useful fly-ash preview
The full 48-point run was deliberately broad. This public view is limited to six 24% binder points at w/b 0.30 and 0.40. Higher-water 0.50 and 0.60 stress-test cells remain in the technical record, but are not presented as print-oriented candidates.
| Binder family | Class F replacement | w/b | Predicted 28-day strength | Screen result |
|---|---|---|---|---|
| Type IL control | 0% | 0.30 | 32.96 MPa | In retained band |
| Type IL + Class F | 20% | 0.30 | 33.74 MPa | In retained band |
| Type IL + Class F | 25% | 0.30 | 39.59 MPa | Above retained band |
| Type IL control | 0% | 0.40 | 40.70 MPa | Above retained band |
| Type IL + Class F | 20% | 0.40 | 36.17 MPa | Just above retained band |
| Type IL + Class F | 25% | 0.40 | 35.64 MPa | In retained band |
Native strength-model point estimates only. These are not measurements, uncertainty intervals or proof of pumpability, extrusion, buildability, open time or interlayer performance.
What the same buildings imply
The quantity envelope compares two 24% binder compositions: a Type IL control and a 25% Class F replacement case. It does not select a water ratio or a qualified mix.
| Building | Printed mass | Control cement | Class F screen: cement + fly ash |
|---|---|---|---|
| Workshop | 25.5–48.3 t | 6.1–11.6 t | 4.6–8.7 t + 1.5–2.9 t |
| Garage | 19.7–37.4 t | 4.7–9.0 t | 3.5–6.7 t + 1.2–2.2 t |
| Barn | 62.2–117.9 t | 14.9–28.3 t | 11.2–21.2 t + 3.7–7.1 t |
| Hybrid house | 26.2–49.6 t | 6.3–11.9 t | 4.7–8.9 t + 1.6–3.0 t |
| Four-building sequence | 133.5–253.2 t | 32.0–60.8 t | 24.0–45.6 t + 8.0–15.2 t |
Approximate proportional planning translation, not a batch ticket, yield calculation or procurement quantity.
The cost answer is not ready
Public evidence does not yet support a complete Idaho Falls material or delivered-cost comparison. Local fine-sand price and grading, Class F route and price, delivered Type IL, admixtures, freight, storage, mixing, pumping, labor, mobilization, protection, testing, waste and tax remain incomplete.
LOGiMIX next step
A location-grade report would bind comparable delivered supplier evidence, select actual lots, reconcile the production system and weather controls, and define the laboratory and equipment trials needed before procurement.
Request a scoped LOGiMIX comparisonReview the Wisconsin reference
Sources and boundaries
- City of Idaho Falls geographic design criteria
- NOAA/NCEI Idaho Falls 1991–2020 normals
- Idaho Transportation Department 2026 supplemental specifications
- USGS Mineral Commodity Summaries 2026 — Cement
The analysis is early-stage decision support. It does not establish a qualified formulation, supplier commitment, delivered quote, code approval, structural adequacy, durability, printability, cost advantage, carbon advantage or guarantee.