Mechanical behavior and phase change of alkali-silica reaction products under hydrostatic compression

DOI: 10.1107/S205252062000846X

Authors: Guoqing Geng (Paul Scherrer Institut; National University of Singapore) , Zhenguo Shi (Swiss Federal Laboratories for Materials Science and Technology (Empa)) , Andreas Leemann (Swiss Federal Laboratories for Materials Science and Technology (Empa)) , Konstantin Glazyrin (Deutsches Elektronen-Synchrotron (DESY)) , Annette Kleppe (Diamond Light Source) , Dominik Daisenberger (Diamond Light Source) , Sergey Churakov (Paul Scherrer Institut; University of Bern) , Barbara Lothenbach (Swiss Federal Laboratories for Materials Science and Technology (Empa); Norwegian University of Science and Technology) , Erich Wieland (Paul Scherrer Institut) , Rainer Daehn (Paul Scherrer Institut)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Acta Crystallographica Section B Structural Science, Crystal Engineering And Materials , VOL 76 , PAGES 674 - 682

State: Published (Approved)
Published: August 2020
Diamond Proposal Number(s): 18643

Abstract: Alkali-silica reaction (ASR) causes severe degradation of concrete. The mechanical property of the ASR product is fundamental to the multiscale modeling of concrete behavior over the long term. Despite years of study, there is a lack of consensus regarding the structure and elastic modulus of the ASR product. Here, ASR products from both degraded field infrastructures and laboratory synthesis were investigated using high-pressure X-ray diffraction. The results unveiled the multiphase and metastable nature of ASR products from the field. The dominant phase undergoes permanent phase change via collapsing of the interlayer region and in-planar glide of the main layer, under pressure >2 GPa. The bulk moduli of the low- and high-pressure polymorphs are 27±3 and 46±3 GPa, respectively. The laboratory-synthesized sample and the minor phase in the field samples undergo no changes of phase during compression. Their bulk moduli are 35±2 and 76±4 GPa, respectively. The results provide the first atomistic-scale measurement of the mechanical property of crystalline ASR products.

Journal Keywords: alkali-silica-reaction; high-pressure X-ray diffraction; mechanical property; phase change

Subject Areas: Materials


Instruments: I15-Extreme Conditions

Other Facilities: Beamline P02.2 at DESY