Experimental investigation on fracture behavior of rubberized engineered cementitious composites under thermo-mechanical loadings

Rubberized engineered cementitious composite (R-ECC) exhibits a ductile fracture mode, but its behavior under high service temperatures remains uncertain. Thus, this study examined the fracture performance at various powder rubber (PR) replacement ratios (0 %, 10 %, 20 %, 30 %) and ambient temperatures (25 degrees C, 50 degrees C, 100 degrees C, 150 degrees C) to explore the fracture mechanism under thermo-mechanical loadings. The analysis focused on failure mode, mode-I fracture energy GF, and ductility index Du. Notably, the entire fracture process was captured utilizing the J-integral method. The results indicated that R-ECC retained its ductile fracture characteristic under service temperatures up to 100 degrees C. Increased fracture elongation of PE fibers at elevated temperatures, combined with the introduction of rubber, prolonged the multi-crack propagation stage, peaking the GF at 70 degrees C. However, PR introduction and high temperatures reduced fiber bridging strength, leading to a decline in peak load and, a decrease in GF at higher temperatures. The J-integral analysis further confirmed that R-ECC exhibited significant ductility. R-ECC generally maintained high fracture ductility, only shifting to brittle failure at 150 degrees C. This study provides insights into the fracture mechanism of R-ECC under thermo-mechanical loadings, demonstrating its applicability under service temperatures up to 100 degrees C, which promotes the broader application and sustainable development of R-ECC in practical engineering scenarios.