THERMOELASTIC STRESS-ANALYSIS - TEMPERATURE STRAIN RELATIONSHIPS IN CONCRETE AND MORTAR

This paper reports the results of tests carried out on concrete and mo rtar in order to determine the variations in temperature brought about by applied loads. Attention is called to the methodological aspects, and the influence of material heterogeneity is investigated by compari ng the values obtained in concrete and mortar with those recorded for a comparatively homogeneous material (PMMA), the aim being to provide an initial assessment of the applicability of thermoelastic analysis t o the materials being considered. The temperature-strain (T, epsilon) - or alternatively, temperature-stress (T, sigma) - diagrams obtained in adiabatic conditions under mono-axial tensile and compressive force s are examined and Gruneisen's parameters are calculated. A clear para llelism between (sigma, epsilon) curves and Young's elastic modulus, E , on the one hand, and (T, epsilon) curves and Gruneisen's parameter o n the other is shown to exist. Finally the heating-cooling phenomena o ccurring in concrete and mortar in compression, as observed both in st atic tests and loading cycles of short duration, are investigated.