The primary objective of this study is to develop the techniques for efficient and economic use of latex modified concrete and mortar overlays as a means of controlling concrete bridge deck deterioration caused by the use of deicing salts. Test results seem to indicate that: slabs with LMC overlays crack at a load about 25% higher than that for slabs without overlay irrespective of the type and thickness of the overaly. The number of cracks is smaller in slabs with LMC overlays under the same load level. The maximum crack width and deflection does not seem to be affected by the presence of the overlay or by salt brine exposure. Under flexural concentrated loads no delamination of the overlays was observed except in few cases and that took place after yielding of the tension reinforcement. Shear-bond strength between the LMC overlays and the substrate is adequate even after exposure to freeze-thaw cycles. Freeze-thaw resistance of LMC overlays, cured for about 6 weeks, was superior to that of air-entrained concrete with embedded reinforcement. The modulus of rupture of LMC exceeds that of AE by about 50% but its fracture toughness is only 17% higher. Corrosion potential is reduced by use of LMC overlays. Mortar overalys using Dow modifier "A" gave the best corrosion resistance. Texturing the surface of an overlay after its initial setting reduces its effectiveness in salt brine penetration and consequently reduces its corrosion resistance. A set retarder on the surface of the substrate may be used in lieu of the costly sand blasting before placing the LMC overlays. For new bridge decks it is recommended to place the overlay after the substrate has cured and its forms removed.

  • Corporate Authors:

    Ohio State University, Columbus

    Engineering Experiment Station, 2070 Neil Avenue
    Columbus, OH  United States  43210
  • Authors:
    • Bishara, A G
    • Tantayanondkul, P
  • Publication Date: 1974-6

Media Info

  • Features: Appendices; Figures; References; Tables;
  • Pagination: 69 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00082899
  • Record Type: Publication
  • Report/Paper Numbers: ODOT-12-74 Final Rpt.
  • Contract Numbers: 14250(0)
  • Files: TRIS
  • Created Date: Apr 8 1975 12:00AM