# Thermomechanical Behavior of Textile Reinforced Cementitious Composites Subjected to Fire
###### Abstract  
The mechanical behavior of textile reinforced cementitious composites (TRC) has been a topic of wide investigation during the past 30 years. However, most of the investigation is focused on the behavior under ambient temperatures, while only a few studies about the behavior under high temperatures have been conducted thus far. This paper focused on the thermomechanical behavior of TRC after exposure to fire and the residual capacity was examined. The parameters that were considered were the fiber material, the thickness of the concrete cover, the moisture content and the temperature of exposure. The specimens were exposed to fire only from one side and the residual strength was measured by means of flexural capacity. The results showed that the critical factor that affects the residual strength was the coating of the textiles and the law of the coating mass loss with respect to temperature. The effect of the other parameters was not quantified. The degradation of the compressive strength of TRC was quantified with respect to temperature. It was also concluded that a highly asymmetrical design scheme might lead to premature failure. s 2019 9 747 20  
A major concern with respect to TRC lies in the fact that the low thickness of TRC elements might end up being a drawback for their fire resistance, since the textile reinforcement is more exposed to high temperatures. At the same time, the most common failure mechanism of concrete due to high temperatures (spalling of the cover) is of small importance in thick elements, while in TRC elements with thickness of a few millimeters it can be critical. Therefore, even though TRC has been widely investigated and already practically used in the past few years for many applications (load bearing or non-load bearing elements in new constructions, strengthening, repairing and seismic retrofitting of existing concrete or masonry buildings, sandwich facade panels, bridge components, curved shell elements, etc. ), there is still no high certainty about the materials' response in fire conditions. The state-of-the-art in the literature includes several publications concerning the temperature effect on TRC. However, a significant amount on them is not focused on TRC alone, but on applications of TRC as a strengthening technique on existing concrete or masonry structures. Studies [1; 2; 3; 4; 5; 6] investigate the effectiveness of a TRC layer as a means of strengthening concrete beams or slabs subjected to high temperatures. In studies [7; 8] TRC has been used on existing concrete substrates; however, these studies have focused only on the effect of high temperatures on the bond between the two different materials. In publications [9; 10; 11], the structural capacity and the effectiveness of the bond between the TRC and masonry substrate has also been tested under exposure to high temperatures. Clearly, the results given by these publications cannot be used as data to work with in the design of TRC structures, since the high concrete (or masonry) mass of the existing building gives thermal inertia to the system which does not exist in slender TRC structures. In studies [12; 13; 14; 15; 16; 17; 18; 19; 20; 21; 22; 23; 24; 25; 26; 27; 28], the structural capacity of TRC alone (not on a different substrate) under elevated or high temperature has been investigated. However, in [12; 13; 14; 15; 16; 17; 18; 19; 20; 21], the maximum temperature that was tested was 650 \({}^{\circ}\)C, and only in publications [22; 23; 24; 25; 26; 27; 28], TRC was investigated under temperatures of 700 \({}^{\circ}\)C-1000 \({}^{\circ}\)C, which corresponds to the realistic temperatures developed in case of a cellulosic fire [29]. Moreover, out of the last group of publications, only in [26; 28] tests have been performed on TRC specimens according to the standard fire curve proposed by EN1363 ([29]), while using glass or carbon fiber reinforcement, which are the most commonly used in structural applications.