Guides
Testing guides for CMT labs, in plain English
Plain-English guides to concrete, soil, aggregate and lab operations. Each explains the purpose, general steps and calculations, with worked examples where a shared tested method exists. Start with the topic hubs or browse the CMT glossary.
Construction materials testing overviewSoil compaction testing overviewCMT glossary
Concrete
06 guides
- ASTM C39: compressive strength of concrete cylindersHow a cylinder break works, how strength is calculated from two diameters and the maximum load, when the L/D correction applies, and what to check.Related tool: Concrete strength calculator
- ASTM C31: making and curing concrete cylinders in the fieldA walk-through of making and curing field cylinders, the initial curing temperature ranges, and how handling errors show up in acceptance results.Related tool: ACI 318 acceptance calculator
- Fresh concrete tests: slump, air, temperature and unit weightA plain-English tour of fresh concrete tests: sampling, slump, air content, temperature and unit weight, and why the field sheet matters later.Related tool: Concrete strength calculator
- Slump test: ASTM C143 field guideWhat the concrete slump test measures, how ASTM C143 results are recorded, and how to avoid confusing slump with strength or acceptance.
- ASTM C109: mortar cube compressive strength guideWhat ASTM C109 mortar cube testing reports, how loaded area relates to strength, and which preparation and reporting details matter.
- ASTM C42: concrete core testing guideHow concrete cores are obtained and tested, how length-to-diameter correction applies, and how ACI core criteria are evaluated.
Soils
11 guides
- The Proctor test: how it works and how to read the curveWhat a Proctor test measures, how each compaction point is calculated, how the curve gives MDD and OMC, and how the zero air voids line keeps you honest.Related tool: Proctor curve calculator
- Standard vs Modified Proctor: ASTM D698 and D1557 comparedHow Standard (D698) and Modified (D1557) Proctor differ in rammer, drop and layers, why Modified gives a higher MDD, and why the right reference matters.Related tool: Proctor curve calculator
- Nuclear density test: field compaction with ASTM D6938How the nuclear gauge test works, the dry density and percent compaction math, the daily standard count check, and the mistakes that cause retests.Related tool: Nuclear density calculator
- Sand cone test: ASTM D1556 procedure and calculationsHow the sand cone field density test works, the four-step calculation from sand in the hole to dry density, and the habits that keep results repeatable.Related tool: Sand cone calculator
- Unified Soil Classification System (USCS) guideHow ASTM D2487 uses gradation and plasticity to classify soil, what USCS group symbols mean, and where judgment and full charts matter.Related tool: USCS classification calculator
- Atterberg limits: liquid limit, plastic limit and PIWhat liquid limit, plastic limit and plasticity index mean, how multipoint results are interpreted, and how the values support soil classification.Related tool: Atterberg limits calculator
- ASTM D698: Standard Proctor test guideHow ASTM D698 establishes a Standard Proctor moisture-density reference, what to record, and how field compaction results use the reference.Related tool: Proctor curve calculator
- ASTM D1557: Modified Proctor test guideHow ASTM D1557 establishes a Modified Proctor reference, how its curve is calculated and reviewed, and why the project must select the method.Related tool: Proctor curve calculator
- Soil compaction testing: field and lab guideHow laboratory Proctor references, field density tests and project acceptance work together in soil compaction testing.Related tool: Nuclear density calculator
- Nuclear density gauge: field guideHow a nuclear density gauge supports field compaction testing, what direct transmission and backscatter mean, and why licensing and daily checks matter.Related tool: Nuclear density calculator
- Sieve analysis: aggregate and soil gradation guideHow sieve analysis produces percent retained and passing, how gradation curves support material description, and what the fineness modulus summarizes.Related tool: Sieve analysis calculator
Lab quality
03 guides
- CMT lab accreditation: AASHTO R18, ISO/IEC 17025 and recordsWhat AASHTO re:source accreditation, AASHTO R18 and ISO/IEC 17025 mean for a small CMT lab, and the records your lab and its software need to keep.Related tool: Sieve analysis calculator
- Construction materials testing: a practical lab guideA practical overview of construction materials testing: how field observations, laboratory methods, calculations and reviewed reports fit together.Related tool: Concrete strength calculator
- CMT technician: role, training and certificationsWhat a construction materials testing technician does, how method-specific training supports reliable records, and where ACI and NICET programs fit.