Effetti della temperatura in esercizio sul comportamento a breve e lungo termine di calcestruzzi fibrorinforzati.

Steel Fibre Reinforced Concretes (SFRC) and Macro Synthetic Fibre Reinforced Concretes (MSFRC) are nowadays widely used to achieve better performances than standard concretes under serviceability conditions. While the short–term properties of these materials have been widely investigated by many researchers their long–term properties have not yet been fully comprehended even if they may be extremely important when considering serviceability limit states. This paper describes the results of an experimental campaign aimed at investigating the effects of moderate temperatures (20 °C to 40 °C) on the long– and short–term behaviour for SFRC and MSFRC. The experimental campaign was implemented in two stages: a) long–term tests under constant loading at increasing temperatures, and b) short–term three–point bending tests on notched specimens performed at different temperatures. The tests showed that temperature has a large influence on the long–term behaviour of MSFRC and that its effect are of lesser extent as far as the short–term behaviour is considered.