The Composite Technologies Corporation (CTC) concrete sandwich system is a unique, patented, pre-engineered, insulated concrete sandwich wall system developed, manufactured and supplied by CTC. The CTC concrete sandwich system comprised of 2-in. thick and 6-in. thick layers of solid concrete divided by 6-in. thick layer of black extruded polystyrene insulation (three layers, each 2-in. thick) and ½-in. thick layer of blue extruded polystyrene. The blue polystyrene sheets incorporated bonded polypropylene membranes on both surfaces. These four layers of foam and two layers of concrete were held together by CTC-manufactured, high-strength, fiber-composite connectors installed on a 16-in. grid.
Thermal conductivities of the panel concrete
and extruded polystyrene foam were tested by ORNL BTC Material Lababoratory
using hot plate apparatus - ASTM C 518-91. Thermal conductivity
of blue extruded polystyrene foam at mean temp. 50 deg. F was k
a = 0.20 Btu-in./hft 2F. Thermal conductivity of the black extruded
polystyrene foam at mean temp. 50 deg. F was k a = 0.21 Btu-in./hft
2F. Thermal conductivity of concrete was k a = 9.09Btu-in./hft 2F.