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Dr. Chiara (Clarissa) F. Ferraris

Dr. Chiara (Clarissa) F. Ferraris is a physicist in the Inorganic Materials Group of the Materials and Structural Systems Division (MSSD) of the Engineering Laboratory (EL) at the National Institute of Standards and Technology (NIST). Dr. Ferraris joined the Inorganic Building Materials Group of the Materials and Construction Research Division in January 1994. She is carrying out studies on rheology of concrete, sorption measurements (Developed the ASTM standard test C 1585), and sulfate attack in concrete (proposed test under consideration by ASTM). Other topics include rubber fibers for plastic shrinkage prevention, alkali-slica reaction, and self-leveling compounds. In the field of cement particles size distribution measurements, she took the lead to provide the cement industry with a reference material for particle size distribution, SRM 114q and 46h and proposed a standard test method to ASTM. Dr. Ferraris has published more than 90 papers.

The main thrust of her work is on the rheological properties of fresh concrete. The scope is to predict the rheological parameters of concrete, i.e., yield stress and viscosity, from the mixture composition and the rheological parameters of the cement paste. A novel method to measure the cement paste rheological properties was developed. This test has the potential to predict the performance of supplementary cementitious materials and chemical admixtures in concrete. She led an international effort to compare all the design of concrete rheometers. This work was under the sponsorship of ACI 236A committee (now ACI 238). She is currently promoting new standard tests to ASTM and developing a granular reference material for paste and concrete rheometers.

From May 1987 to December 1993, prior to joining NIST, Dr. Ferraris was a Research Physicist at the Washington Research Center of W.R. Grace & Co., in Columbia, Maryland. In that position, she obtained three patents on admixtures for concrete and cement.

From March 1980 to April 1987, Dr. Ferraris worked at the Swiss Federal Institute of Technology in Lausanne, Switzerland with Professor Wittmann and carried out studies on shrinkage of cement and concrete. This research led to a Ph.D. thesis completed in 1986.

Dr. Ferraris is a Fellow of the American Concrete Institute (ACI) since 2003 (member since 1991). She a member of TAC (Technical Activity Committee) since 2008. She was also past chair of the ACI 238 "Workability of Fresh Concrete" (2006-2010) and ACI 236 "Material Science of Concrete" (2001-2006). Also, She is involved in ASTM as a member of committees on Fineness (C01.25) and Fluid Penetration (C09.66). Since 2007, she is the sub-chair of the ASTM committee Workability (C01.22) and the secretary of the ASTM committee on Sulfate Resistance (C01.29). She was the program chair (1997), and chair (2000-2001) for the Cement Division of the American Ceramic Society (ACerS). She was the associate editor of the "Journal of Materials in Civil Engineering" (2003-2010). Since 2009, she is the associate editor for "Cement and Concrete Research."

In 2008, Dr. Ferraris received the Delmar L. Bloem Distinguished Service Award" from ACI for outstanding leadership in ACI 236 and 238. She is the recipient of the 2001 BFRL Communication Award for her report on the "Comparison of Concrete Rheometers International tests of LCPC (Nantes, France) in October 2000." She also received in 2002 and 2008 "NIST Equal Employment Opportunity/Diversity Award" for consistently encouraging careers in science. and engineering for women.

Dr. Chiara (Clarissa) F. Ferraris


Materials and Structural Systems Division
Inorganic Materials Group


Swiss Federal Institute of Technology, Lausanne, Switzerland, Ph.D., Technical Science, 1986

Swiss Federal Institute of Technology, Lausanne, Switzerland, M.S., Physics, 1980


Phone: 301-975-6711