Preferred orientation of ettringite in concrete fractures

Journal Article · Sat Jan 31 00:00:00 EST 2009 · Journal of Applied Crystallography

DOI:https://doi.org/10.1107/S0021889809015349· OSTI ID:960280

Wenk, Hans-Rudolf; Monteiro, Paulo J.M.; Kunz, Martin; Chen, Kai; Tamura, Nobumichi; Lutterotti, Luca; Delacroz, John

Sulfate attack and the accompanying crystallization of fibrous ettringite [Ca{sub 6}Al{sub 2}(OH){sub 12}(SO{sub 4}){sub 3} {center_dot} 26H{sub 2}O] cause cracking and loss of strength in concrete structures. Hard synchrotron X-ray microdiffraction is used to quantify the orientation distribution of ettringite crystals. Diffraction images are analyzed using the Rietveld method to obtain information on textures. The analysis reveals that the c axes of the trigonal crystallites are preferentially oriented perpendicular to the fracture surfaces. By averaging single-crystal elastic properties over the orientation distribution, it is possible to estimate the elastic anisotropy of ettringite aggregates.

• Research Organization: Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: Advanced Light Source Division
• DOE Contract Number: DE-AC02-05CH11231
• OSTI ID: 960280
• Report Number(s): LBNL-1913E; JACGAR; TRN: US0904365
• Journal Information: Journal of Applied Crystallography, Vol. 42, Issue 3; ISSN 0021-8898
• Country of Publication: United States
• Language: English

Related Subjects

58
ANISOTROPY
CONCRETES
CRYSTALLIZATION
DIFFRACTION
DISTRIBUTION
ELASTICITY
FRACTURES
GRAIN ORIENTATION
ORIENTATION
SULFATES
SYNCHROTRONS
Cement Ettringite X-ray microdiffraction