Petrography Testing
Petrography Testing
Concrete petrographers use microscopic examination of concrete to characterize its composition and condition. This is particularly useful in determining causes of premature concrete deterioration such as scaling, delamination and low strength. Among the many other insights that petrographic examination provides, it can be used for studying air voids, a determining factor in many concrete durability issues and for evaluation of materials used in concrete production, such as fly ash quantification. The Master Builders Solutions petrography lab is managed by experienced petrographers with backgrounds in geology.
ASTM C856 (Petrographic Examination of Hardened Concrete)
A petrographic examination characterizes the composition and condition of concrete or other hardened hydraulic-cement mixtures and can be used to determine potential causes for concrete scaling, delamination and low strength among others.
Scaling
During a petrographic examination, evidence of inadequate curing can be determined, which can be a cause of scaling.
Delamination
Petrographic observations can determine if concrete was finished early, which can be a cause of delamination.
Low Compressive Strength
Under a microscope, observations can indicate if retempering with water in excess of the mix design has occurred sometime after initial batching, which is a common cause of low compressive strength.
ASTM C457 (Air-Void Parameters in Hardened Concrete)
An air-void parameters determination is performed to assess the volume percent air in hardened concrete and assess how well the air is distributed throughout the concrete. This is important for determining causes of freeze-thaw distress and low compressive strength.
Learn more about hardened air content in concrete