Performance of latex modified concrete overlay in the gulf environment

الملخص EN

This paper presents results of a study on the performance of latex modified concrete (LMC) overlay under the local environment.

The assessment of LMC overlay to improve the durability of concrete against corrosion of rebars was evaluated.

Several panels with two different overlay thicknesses were cast and subjected to natural local environments in an exposure site.

Corrosion of rebars was monitored for a period of ten month and chloride versus depth profile of the slabs were plotted at the end of the monitoring period.

The effect of the large temperature variations in the Arabian Gulf on the permeability of LMC overlay was investigated by subjecting test cube specimens to 60, 90, and 120 heat cycles and measuring the corresponding permeability.

Finally, the delamination phe-nomenon was investigated by testing composite beams consisting of LMC overlay and base concrete under cyclic loading at different stress levels.

The test results indicate that the LMC overlay is more effective than super plasticized Portland cement concrete (S?CC) in controlling the permeation of moisture and chloride.

The half-cell potential readings reflected a substantial delay of corrosion initiation by using 40 mm thick LMC overlay relative to a 25 mm thick LMC overlay and to a control panel with no overlay.

Also it indicates the beneficial effects of latex in resisting the thermal incompatibility of concrete components measured in terms of permeability.

Good bond between LMC overlay and base concrete is ensured as no delamination was observed under cyclic loading with peak load ot up to 80 percent of the ultimate load.