Document Type
Thesis
Date of Award
1-31-1988
Degree Name
Master of Science in Civil Engineering - (M.S.)
Department
Civil and Environmental Engineering
First Advisor
Methi Wecharatana
Second Advisor
Charles Franklin Peck
Third Advisor
C.T. Thomas Hsu
Abstract
Latex modified concrete and polymer concrete have been widely used for bridge deck overlays and crack repairs for the past decade. In recent years, many of these repaired structures were found to be defective. The causes of these failures are not clearly confirmed. Some blame the quality of the latex products while manufacturers accuse the contractors of improper placement and/or surface preparation. While most of these failures largely appeared to be debonding and delamination of the overlays, excessive cracks, possibly shrinkage cracks, were also reported in the overlaid LMC.
To evaluate the suitability of using latex modified concrete for crack repairs and overlays, this study is aimed at investigating the mode of failure in overlaid composites such as LMC, and normal concrete. Attempt will also be made to resolve the severe shrinkage and debonding problems by introducing hooked-end steel fibers in the overlaid cementitious composites. Several series of experiments were conducted with different types of overlaid materials.
Test results using latex with styrene butadience indicate that latex modified concrete is not suitable for crack repairs due to poor bonding, low strength, and excessive shrinkage. The quality of LMC using the recommended mix-proportion is poor and inconsistent. The addition of fibers to both normal concrete and LMC provides excellent overlaid materials which have reduced shrinkage cracks and improved bond between the overlay and the original concrete.
Recommended Citation
Lo, Chen-Hoang, "Use of latex modified concrete for repairs and overlays" (1988). Theses. 3258.
https://digitalcommons.njit.edu/theses/3258
