Evaluation of self-healing performance of a smart composite material (SMA-ECC)

Abstract

The durability of cementitious materials is affected by the presence of cracks. This paper proposed a novel composite material and evaluated its crack healing ability. This material consisted with engineered cementitious composite (ECC) and shape memory alloy (SMA) fibers. A total of 12 specimens were made and tested under flexural loads. Test parameters included material type and target displacement level. Test results indicated that specimens with SMA-ECC had great increase in strength and ductility compared with specimens with concrete. Specimens with SMA-ECC exhibited promising crack healing ability by effectively reducing the crack number and width. The self-healing ability reduced with increasing target displacement level. The self-healing ability was further investigated through ultrasonic pulse test. Ultrasonic pulse test results were consistent with the mechanical test results, indicating effectiveness of this test method. This composite material SMA-ECC has promising application in infrastructure critical for security to mitigate damage and heal cracks, and increases durability of the structure, and reduces maintenance cost.