Development of Equipment for Heat Treating Internally Sealed Concrete - Phase I

摘要

The addition of monomers or the inclusion of wax within highway bridge decks are two methods being used to prevent salt penetration during winter deicing. Both of these methods require the addition of heat until the upper two inches of the concrete deck reaches 160-190 F. This study developed concepts for both a solar powered and a solar assisted system for heat treating internally sealed concrete. The heat transfer characteristics of reinforced portland cement concrete were analyzed, and the critical parameters of thermal diffusivity and conductivity determined. Solar isolation data was collected from six areas of the country during months typical of the construction season, and correlated with ambient temperatures and wind data for the same locations and periods, in order to derive both the net energy input available and the net energy requirement of the system. Three configurations of flat plate solar collectors were investigated and computer analyzed to determine their ability to satisfy the system requirements. A modular collector system was recommended on the basis of its anticipated durability and longevity, ease of handling, and overall lower life-cycle cost. The design was optimized and computer simulations were run on the system to evaluate performance in typical U.S. cities.