Petrographic Analysis Companies – ASTM C295 & C856

ASTM C295 / C295M: Standard Guide for Petrographic Examination of Aggregates for Concrete.

ASTM C856: Standard Practice for Petrographic Examination of Hardened Concrete.

Uses of Petrographic Analysis

Petrographic analysis is the starting point in the evaluation of concrete. They include:

  1. Finding the causes of inferior quality, distress, or deterioration of concrete.
  2. Determination whether the concrete in a construction was or was not as specified.
  3. Provide description of the cementitious matrix, including qualitative determination of the kind of hydraulic binder used, degree of hydration, degree of carbonation if present, presence of a mineral admixture, the nature of the hydration products, adequacy of curing, and unusually high water – cement ratio of the paste.
  4. Identify whether the concrete has been subjected to and affected by sulfate attack, or other chemical attack, or early freezing, or to other harmful effects of freezing and thawing.
  5. Determination whether concrete subjected to fire is essentially undamaged or moderately or seriously damaged.
  6. Determination of the factors that caused a given concrete to serve satisfactorily in the environment in which it is taken from
Forensic Evaluation (petrography) Forensic Evaluation (petrography)

Fire-damaged concrete.

Forensic Evaluation (petrography) Forensic Evaluation (petrography)

Sulfate attacked concrete

Forensic Evaluation (petrography) Forensic Evaluation (petrography)

Evaluation of granite sample