ML12157A315

1500 - E117 - Concrete Technology and Codes - 38a - Petrographic Report

ML12157A315
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Issue date:	06/05/2012
From:	Office of the Chief Human Capital Officer
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Download: ML12157A315 (55)

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Concrette Tech C hnolog gy and Codes s

The Petrographic Report

Petrographic Examination What is it?

How is it done?

What can it do?

What cant it do?

What will the petrographic report say?

How do I critically read a petrographic report?

Structural Evaluation LARGE scale to sma ll scale

Structural Evaluation ACI 364.1R Guide Guide for Evaluation of Concrete Structures Prior to Rehabilitation ACI 349.3 Evaluation of Existingg Nuclear Safety-Related Concrete Structures

• document review d i

• NDE

• field inspection

• sampling

• condition survey

• material testing (laboratory)

Structural Evaluation ACI 364.1 Table 6.1(a)

Evaluation of Properties of Concrete

Structural Evaluation ACI 364.1 Table 6.1(b)

Evaluation of Physical Conditions of Concrete

Structural Evaluation Importance of Appropriate Samples

Petrography Defined as the systematic description and classification of rocks (or concrete),

especially through microscopical examination Methods and techniques for concrete petrography derived from geology, metallurgy, and ceramics

Petrographic Examination ASTM C 856-04 856 04 - Standard Practice for Petrographic Examination of Hardened Concrete Guideline for microscopical analysis of concrete and related materials M h d and Methods d techniques h i may vary with i h scope of investigation

Petrographic Examination Examine sample as-received as received

Petrographic Examination Select areas for sub sub-sampling sampling

Petrographic Examination Lapped surface

Petrographic Examination Stereomicroscope

Petrographic Examination Fresh fracture

Petrographic Examination Thin section

Petrographic Examination Polarized light (petrographic) microscope

Petrographic Examination Powder mount

Petrographic Examination CAN Describe the general composition, quality, and condition of the concrete and its constituents

Petrographic Examination CAN Estimate air content and adequacy of air-air void system

Petrographic Examination CAN Identify supplementary cementing materials

Petrographic Examination CAN Determine general compliance with mix design (aggregates, air content, SCMs, w/c)

Petrographic Examination CAN Determine depth of paste carbonation

Petrographic Examination CAN Evaluate workmanship (consolidation, finishing, curing)

Petrographic Examination CAN Evaluate possible causes of distress

Petrographic Examination CAN Recommend additional tests to investigate the problem Air void system analysis (ASTM C457)

Scanning electron microscopy (SEM-EDX)

Cement content analysis (ASTM C1084)

Compressive strength testing (ASTM C42)

X-ray diffraction X-ray X ray fluorescence Chemical tests

Petrographic Examination CANT Determine cement content Determine cement type Confirm presence presence, type type, or quantity of chemical admixtures Determine timing of water additions Determine precise proportions of mix Determine concrete strength

Petrographic Report Background information/ reason for testing Conclusions Summary of observations Discussion Methodology of examination Photographs D t pages Data

Evaluating a Report Were samples representative?

Do observations/data agree and seem p

plausible?

Do photographs illustrate observations?

Do conclusions drawn from observations seem logical?

Is original question addressed?

NEVER BE AFRAID TO QUESTION THE PETROGRAPHER!