Thermal Stresses and Deflection of Sandwich Panels

Sandwich panels with foamed cores and cold-formed metal faces are becoming more and more popular as building enclosures. It is not unusual that the temperature difference between the inside and outside wall surfaces may exceed 100°F. Experimentally, full-sized sandwich panels of different profiles were placed in a heat chamber in single and double spans. One side of the panel was subject to the heat flux generated in a heat chamber, whereas the other side was at room temperature. Special precaution was taken so that the temperature inside the heat chamber was uniform. Thermistors were used to detect the surface temperature of the panel. Strain and dial gages were also used. Formulated as an ordinary fourth-order differential equation, using suitable boundary conditions, expressions were derived for deflection, flexural stresses in the facings, and shear stresses in the core. Using the method of consistent deformations, similar expressions were derived for multiple spans.