CONSTRUCTION AND PERFORMANCE OF AN EXPERIMENTAL THIN-BONDED CONCRETE OVERLAY PAVEMENT IN HOUSTON.

The use of thin-bonded concrete overlay (TBCO) pavements is rapidly emerging as a viable means of rehabilitating concrete pavements. In recent years, several projects have been constructed, and valuable information has been gathered with the Iowa Department of Transportation leading the way. A survey of the available literature, however, reveals that the information is scattered and, in most cases, it is difficult to make statistical inferences because either the information was not collected for any particular purpose (i.e., not task-oriented) or there is no prior well-defined experiment design. During the summer of 1983, an experimental 1,000 ft of thin-bonded concrete overlay pavement was placed on Interstate 610 (Loop 610), a 4-lane divided freeway in Houston, Texas. The original pavement structure is a continuously reinforced concrete pavement. Five design sections were constructed. Concrete reinforcement and overlay thickness were used at three and two levels, respectively. Presented in this paper are several aspects of the experimental project. First, the experiment design is discussed, along with project specifications, and a measurement program. Second, actual construction is presented, and salient features outlined. Third, initial results (including field and laboratory tests, Dynaflect deflections, and road profile data) are analyzed. Fourth, a 6-month performance report is made. In closing, conclusions and recommendations derived from the study are presented for those individuals and agencies contemplating the use of TBCOs for the rehabilitation of portland cement concrete pavements.