The Construction Materials Group provides a level of assurance to designers and construction teams that the primary building materials meet established criteria through accepted standardized testing protocol.
RJLG’s experts work with clients to minimize material replacements, reduce the likelihood of deterioration, avoid potential failures and investigate and evaluate construction materials related problems and failures. Engineering support, trained technical personnel and a team approach have been the keys to success.

Petrographic examination is commonly the method of choice when evaluating the microscale condition of hardened concrete. Petrography aids in the assessment of quality, durability, and causes of deterioration in concrete. Various other construction materials such as aggregates, mortar, grout, plaster, and stucco may also be examined using this technique. Petrographic analysis is carried out using a combination of tools including: visual inspection, stereomicroscopic evaluation, polarized light microscopy (PLM), and scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS). Various sample methods can be used such as powder mounts, fractured surfaces, fluorescent dye impregnated polished thin sections, and epoxy impregnated polished sections.
Petrographic examinations are carried out in compliance with guidelines provided in ASTM C856 “Standard Practice for Petrographic Examination of Hardened Concrete”. Additional standard reference methods are also used from which the following information can be derived:
- Condition of the concrete
- Estimation of air content
- Mix design
- Quality of cement and aggregate
- Type and quantity of mineral admixture
- Water-to-cement (W/C) ratio of concrete
- Causes of distress or deterioration
- Alkali silica or alkali carbonate reactions
- Sulfate attack
- Acid attack
- Delayed ettringite formation (DEF)
- Fire damage
- Freeze thaw damage
- Air void analysis (As described by ASTM C 457)
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