Fiber reinforced cement based composites

Cement has good compressive properties but poor tensile strength, which is critical for composites. To solve this challenge, different types of reinforcing fibers, such as glass, carbon, poly vinyl alcohol, steel, asbestos, aramid or cellulosic fibers have been used in the last decades. This chapter discusses the advantages and the challenges of each type of reinforcing fibers in cement based composites. The main benefits of adding reinforcing fibers in cement are the improvement of tensile strength, flexural strength and toughness. Moreover, fibers can also delay or prevent crack propagation where fiber size plays an important role in crack-bridging mechanism. Macrofibers bridge macroscale cracks, avoiding further crack growth, while microfibers are more effective at bounding microcracks and prevent them from becoming macrocracks. Furthermore, fibers increase toughness of the fiber-cement composites (FCCs) by absorbing energy, friction, and even by pull-out phenomenon.