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Aggregate and Petrographic Laboratory Overview

Laboratory Purpose 

The Aggregate and Petrographic Laboratory (APL) at the Turner-Fairbank Highway Research Center (TFHRC) provides facilities for the evaluation, preparation, and testing of aggregate sources, products, and samples for use in concrete, asphalt mixtures, and granular base course applications. Staffed by an experienced geologist and petrographer, the APL is able to conduct research, work with other TFHRC laboratories in characterizing research materials and deterioration mechanisms, and assist in forensic evaluations of construction materials for Federal Highway Administration (FHWA) and other Federal and State agencies.

Laboratory Description

Facilities are available for identifying and characterizing the quality of mineral aggregates using mechanical and microscopy techniques. The Petrography Laboratory includes state of the art transmitted and reflected light compound and reflected light microscopes and image-capturing tools. The APL regularly collaborates with the Chemistry and Concrete Laboratories.

Recent Accomplishments and Contributions


  1. Mengesha Beyene, Richard Meininger & Jose F. Munoz (2022): Mineralogic and petrographic evaluation of aggregate quality – effect on compressive strength of concretepavement, International Journal of Pavement Engineering, DOI: 10.1080/10298436.2022.2088756;
  2. Mengesha Beyene & Richard Meininger, 2021, A case study of distress mechanism(s) in a concrete structure foundation in the saturated zone and above the saturated zone, Journal of Microscopy, October 6, 2021;
  3. Krishna Siva Teja Chopperla, Thano Drimalas, Mengesha Beyene, Jussara Tanesi, Kevin Folliard, Ahmad Ardani, and Jason H. Ideker, Cement and Concrete Research Combining reliable performance testing and binder properties to determine preventive measures for alkali-silica reaction Cement and Concrete Research, Volume 151, January 2022, 106641
  4. M. Beyene and R. Meininger, ASR as the Cause of Distress in Concrete Pavements Made from Purported ACR Aggregate, ACI Material Journal, Technical Paper, V.118, No.2 pp.67-82, 2021.Mengesha Beyene, Jose Munoz, Richard Meininger, and Anant Shastry, Reactive mineral phases in Alkali Carbonate reaction (ACR) Reference Aggregate, ACI Material Journal, Issue 6, V. 117, pp.281-292, 2020.
  5. Jussara Tanesi, Thano Drimalas, Krishna Siva Teja Chopperla, Mengesha Beyene, Jason H. Ideker, Haejin Kim, Luca Montanari, and Ahmad Ardani, Divergence between Performance in the Field and Laboratory Test Results for Alkali-Silica Reaction, Journal of Transportation Board, 2020, 
  6. Mengesha Beyene, & Richard C. Meininger, Microscopy as a Tool to Investigate Low Strength Concrete in New Slip-Form Pavement, 17th Euroseminar on Microscopy applied to Building materials, p. 220-227, Toronto, Canada, May 23-24, 2019
  7. Sada Sahu, Mengesha Beyene, & Richard C. Meininger, Characterization of carbonated calcium silicate cement-based concrete, 17th Euroseminar on Microscopy applied to Building materials, p. 214-219, Toronto, Canada, May 23-24, 2019
  8. M.A. Beyene & R.C. Meininger Alkali Reactive Carbonate Rocks: Is it Alkali Silica Reaction (ASR) or Alkali Carbonate Reaction (ACR)?, Sixth International Conference on Durability of Concrete Structures, Paper Number ICC26, 18 - 20 July 2018, University of Leeds, Leeds, West Yorkshire, LS2 9JT, United Kingdom.
  9. Mengesha A. Beyene, Jose F. Munoz, Richard C. Meininger, and Carmelo Di Bella,“Effect of Internal Curing as Mitigation to Minimize Alkali-Silica Reaction Damage”, ACI Material Journal, May/June 2017.
  10. Mengesha A. Beyene, Richard C. Meininger, Nelson H. Gibson, Jose F. Munoz & Jack Youtcheff, “Forensic investigation of the cause(s) of slippery ultra-thin bonded wearing course of an asphalt pavement: influence of aggregate mineralogical compositions”, International Journal of Pavement Engineering, V17, Issue 10. 2016.
  11. Tanesi, Jussara, Bentz, Dale P, Jones, Scott Z, Mengesha, Beyene, Kim, Haejin, Ardani, Ahmad, Arnold, Joshua, and Stutzman, Paul E, “Influence of Aggregate Properties on Concrete Mechanical Performance”, Transportation Research Board, 96th Annual Meeting, Publication 2017, Washington, D.C. 
  12. Tanesi, J., Kim, H., Beyene, M., and Ardani, A., “Super Air Meter for Assessing Air-Void System of Fresh Concrete”, Advances in Civil Engineering Materials, Vol.5, No. 2, 2016, pp. 22-37.
  13. Jussara Tanesi, Haejin Kim, Mengesha Beyene, A. Ardani, “Super Air Meter for Assessing Air-Void System of Fresh Concrete”, Conference paper, 2015 TRB Annual meeting.
  14. Muzenski, Scott W, Flores-Vivian, Ismael, Beyene, Mengesha A, and Sobolev, Konstantin “Performance of Fiber/Reinforced Composites with Nano-particle-based Polymethyl Hydrosiloxane Emulsions”, 13P., TRB 93rd Annual Meeting Compendium of Papers, 2014.
  15. J.F. Muñoz, C. Balachandran, Y. Yao, A. Shastry, L. Perry, M. Beyene, and T. Arnold, “Forensic investigation of the cause(s) of slippery ultra-thin bonded wearing course of an asphalt pavement: influence of binder content”, International Journal of Pavement Engineering. July 2016. DOI: 10.1080/10298436.2016.1199870.
  16. Petrographic Methods of Examining Hardened Concrete: A Petrographic Manual, FHWA-HRT-04-150, July 2006 

Ongoing Projects

  1. Research on marginal aggregates: ACR Study on potentially reactive carbonate aggregates from different sources.
  2. Characterizing Dolomitic Aggregates from Different Sources for their Potential Expansivity in Concrete
  3. Developing a new petrographic evaluation method to evaluate recycled concrete aggregates (RCAs) from different sources for Use in a new Concretes - Evaluating the Quality of Recycled Concrete Aggregates (RCAs) using Petrographic and Fluorescent Image Analyses 
  4. Developing a direct quantitative method to measure air void characteristics in compacted asphalt mixtures
  5. Influence of aggregate quality on compressive strength of concrete in new slip-form pavements and asphalt pavements.
  6. Forensic evaluations of construction materials for Federal Highway Administration (FHWA), State departments of transportation (DOTs), and other Federal Agencies. 
  7. Contribution to Standards/ Specifications:

    - Submitted results of case studies of a working sample preparation procedure for ASTM C 457 (method C) and a companion marginally polished concretes to the ASTM C09.65 committee chair. 

    - ASTM Round robin CN Tower concrete with ASTM C457 Method C Air Void Analysis to validate the ASTM C 457 Method C.

    - Have been requested to revise and update the Alkali-Carbonate Reaction (ACR) portion of the ACI 221 document based upon research findings on ACR in the TFHRC APL.
  8. Determination of aggregate rock types and mineralogical compositions. Some examples are shown below:

Table 1. Example Aggregate Rock Types and Mineralogical Compositions

Aggregate Rock Type Mineralogical Compositions
Natural Sand Quartz with lesser amounts of quartzite/strained quartz and chert and minor amounts of fine and coarse-grained ferruginous sandstone, granitic rock, and feldspar.
Gravel Quartz, quartzite, chert/chalcedonic chert, with lesser amount of sandstone.
Limestone Fine-grained micritic limestone locally containing thin intercalated layers/lamination of argillaceous limestone.
High-Absorption Limestone Mainly the mineral calcite. Observed limestone particles are predominately micritic limestone and contain sparse marine fossil remains.
Granite, No. 57 Stone This aggregate granite is mainly composed of quartz and feldspar with lesser but appreciable amounts of biotite locally associated with some muscovite.
Green Stone Meta-basalt that mainly consists of feldspar (perhaps albite), chlorite, and actinolite. Other minerals include calcite, epidote, and biotite were also observed.
Granitic Gneiss Quartz and feldspar with lesser amounts of biotite and muscovite, plus trace amounts of secondary minerals including calcite, epidote, and sericite.
Diabase Diabase/dolorite chiefly consists of plagioclase feldspar and pyroxenes.
Quartzite and Sandstone Mix The quartzite contains quartz and feldspars plus traces of amphibole and mica. The sandstone consists of sand-sized quartz and feldspar clasts. There are also lesser amounts of microcrystalline quartz cemented with what appears to be argillaceous/clayey and carbonate matrix. Traces of calcite and black miscellaneous ferruginous materials were also observed in the matrix of the rock.
Marble Dolomitic marble containing finer-grained portions consisting of darker argillaceous materials. Traces of strained quartz and metachert were observed locally.
Dolomite The aggregate consists of somewhat medium-grained dolomite and what appears to be relatively fine-grained dolomite with a fine-grained argillaceous/clayey matrix. The fine-grained dolomite appears textually similar to argillaceous dolomitic limestone, which is known to have caused ACR and (in recent studies) shown to have caused ASR.

Table 2. Example Rock Types and Mineralogical Compositions

Rock Type Relatively High-Abundance Minerals Minor Minerals
Diabase(dolerite) Plagioclase feldspars and pyroxenes Traces of opaque grains 
Rhyolite, dacite, andesite, basalt, trachytic basalt/trachyte, quartzite, and quartz schist Quartz, sanidine, and plagioclase in rhyolite; plagioclase and quartz in dacite; plagioclase feldspars, pyroxene, and olivine in basalt; Plagioclase feldspars, hornblende, and pyroxene in andesite; alkali feldspar (sanidine) and plagioclase in trachyte/trachytic basalt; Quartz in quartzite and quartz schist Glass and cryptocrystalline silica in rhyolite, andesite, and dacite; Chlorite after amphibole in dacite; amphibole (hornblende) and Fe oxides (opaque grains) in trachyte and basalt; micas in quartz schist
Mainly quartzite with minor sandstone Quartz Mica in some quartzite matrix and traces of feldspar
Mainly pure limestone; lesser amount of siliceous limestone, argillaceous limestone, and dolomitic limestone Calcite Chert, chalcedony, dolomite, argillaceous/clayey laminations, iron sulfide

Note: the classification of minerals as major and minor is qualitative and based upon only the observed thin sections (two thin sections per sample).

Laboratory Capabilities

The APL Laboratory is capable of aggregate preparation and sizing; mechanical and durability testing; and characterization and classification of aggregate types for use in concrete, asphalt, and granular base courses and drainage layers. The APL has tools to help identify performance issues and investigate degradation and distress mechanisms in concrete and other highway materials.

Laboratory Equipment

  • State of the art transmitted and reflected light compound optical microscope and stereomicroscope 
  • Rapid-Air 457 Air-Void Analyzer
  • State of the art thin section-making equipment 
  • Sate of the art lapping and polishing equipment.
  • State of the art laser guided saw to cut and section bigger samples.
  • Mineral aggregate crusher, grinder, and pulverizer
  • Sieving and washing equipment
  • Full sets of certified standard and intermediate-size sieves for coarse and fine aggregates and for the sizing of minus No. 200 microfine materials using sieves, hydrometer, and laser analysis. 
  • Various methods of shape, angularity, and texture analysis are available, including:  
    • Aggregate Image Measurement System (AIMS2) device
    • American Association of State Highway and Transportation Officials (AASHTO) Superpave methods
  • Durability and compaction equipment include the Micro-Deval device for fine and coarse aggregate degradation in wet exposures, plus standard and modified proctor testing equipment. 
  • Cutting, lapping, and polishing equipment—for preparation of petrographic thin sections and other specimens—is available in the materials preparation labs.
  • The Geotechnical Laboratory at TFHRC also has aggregate triaxial testing equipment available, used for resilient modulus of pavement layers, plus research equipment for characterizing shear strength of compacted granular aggregate materials.