DETERIORATION OF OUTSIDE WALLS MADE WITH CONCRETE BLOCKS CONTAINING PYRITE

Deterioration of outside walls of private houses constructed with hollow concrete blocks and covered with a single layer of white cement-based coating occurred. Six years after construction, the walls presented a random local ejection of the coating leaving in its place a rust colored deteriorated material. Similar stains on the wall surface also appeared. Scanning electron microscopy and x-ray spectroscopy and diffraction investigations on sound and deteriorated samples showed that the deterioration results from the oxidation of pyrite nodules of some mm of diameter included in the coarse aggregate of the concrete mixture of the blocks. The oxidation process of the pyrite occurred in wet conditions and in contact with cement compounds producing expansive gypsum and colloidal ferrous hydroxides. The random cracking and low permeability of the coating were contributing factors to the deterioration process.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/isbn/0870311131
• Corporate Authors:

  American Concrete Institute (ACI)

  38800 Country Club Drive
  Farmington Hills, MI  United States  48331
• Authors:
  • Gallias, J L
• Conference:
  • Sixth CANMET/ACI International Conference on Durability of Concrete
  • Location: Thessaloniki, Greece
  • Date: 2003-6-1 to 2003-6-7
• Publication Date: 2003

Language

• English

Media Info

• Features: Figures; Photos; References; Tables;
• Pagination: p. 607-620

Subject/Index Terms

• TRT Terms: Coarse aggregates; Concrete structures; Durability; Pyrite; Reactions in concrete; Structural deterioration and defects
• Subject Areas: Highways; Materials; I32: Concrete;

Filing Info

• Accession Number: 00964651
• Record Type: Publication
• ISBN: 0870311131
• Report/Paper Numbers: SP-212-38
• Files: TRIS
• Created Date: Oct 31 2003 12:00AM