# Temperature Impact on Engineered Cementitious Composite Containing Basalt Fibers
###### Abstract  
Engineered cementitious composite (ECC) is a new generation of fiber-reinforced concrete with high ductility and exceptional crack control capabilities. However, ECC can suffer a substantial reduction in ductility when exposed to elevated temperatures resulting in a loss of crack-bridging ability. In this study, the effect of adding basalt fiber (BF), which is an inorganic fiber with high-temperature resistance for the production of ECC, was studied. Moreover, the change in the mechanical properties of ECC, including compressive, tensile, and flexural strength, was experimentally investigated under elevated temperatures up to 400 \({}^{\circ}\)C. The results showed that the addition of BF to reinforced ECC improved the tensile and flexural strength of concrete effectively, but compressive strength marginally decreased. A significant decrease was observed in the range from 300 to 400 \({}^{\circ}\)C, while it increased smoothly when heated up to 300 \({}^{\circ}\)C. The compressive and flexural strength diminished after a slight strain gained when heated up to 100 \({}^{\circ}\)C. This work paves the way for future investigations focusing on the development of high-temperature resistance ECC. caphead=0,outer  
performance index and the stress performance index [21; 22]. The stress performance index first involves cracking strength and is defined as the ratio of the tensile strength of the composite to the initial cracking strength. Both the energy and stress performance indices must be larger than the unity to ensure multiple cracking behavior [23]. Fibers have a very important role in the crack bridging action of ECC composites, and fiber rupture depends on fiber strength and their chemical bonding within the concrete matrix [24]. To study the chemical bonding of the fibers within the composite medium, microstructural and micromechanical properties of ECC are generally evaluated using SEM and AFM [25], X-ray micro-computed tomography (\(\mu\)CT) [26], and the single-fiber pullout test [25; 27]. Traditional ECC materials contain polyvinyl-alcohol (PVA) fibers known as PVA-ECC, while other fibers with inorganic (e.g., carbon, steel, glass, and basalt fibers), polymeric (e.g., polypropylene (PP), polyester, polyethylene (PE), and nylon) nature and natural fibers (e.g., silk, wool, asbestos, wollastonites, coir, cotton, and sisal) have recently been used widely [28; 29; 30]. Polyvinyl-alcohol fibers exhibited better and more consistent ductility improvement compared to other types of fibers. Polypropylene fiber is softer, cheaper, and it disperses faster compared to PVA or PE fibers, which results in better workability of the fresh composite [31]. Moreover, PP fiber has better durability when exposed to an alkaline environment due to the fact of its hydrophobic and non-polar nature [32]. Despite the advantages offered by adding fibers in ECC compositions, some drawbacks, such as a reduction in compressive strength, and an increase in shrinkage and porosity were reported for excess use of fibers [33]. Virgin PE fiber has low mechanical bonds, and they are vulnerable to degradation in the alkaline concrete environment [34; 35; 36]. Hence, some interface modifications and surface treatment are required to improve fiber/matrix bonding and stability [36]. Natural fibers, particularly those with plant origin, show good promise in improving flexural performance and reducing shrinkage. However, natural fibers are generally of very restricted durability which limits their utilization. Man-made fibers, such as steel and carbon fibers, are found more commonly in conventional ECC. Among all, basalt fiber (BF) attracts significant attention due to the abundance of basalt resources and low cost and low carbon and energy footprints during manufacturing [36]. Engineered cementitious composite can be classified as a high-performance fiber-reinforced cementitious composite with a ductility that ranges from 3% to 5% of strain having 1.5-2% fiber content by volume [18; 19; 20].