Normal distribution analysis of fracture parameters of alkali-activated slag seawater column coral aggregate concrete

It is critical to study the fracture behavior of alkali-activated slag columnar coral aggregate concrete (ASCCAC), especially under ocean environment. Furthermore, it is necessary to also consider the microstructure of the specimens and fictitious crack growth. Thus, this paper is mainly aimed at evaluating the effects of average grain size (G = 6 mm, 7 mm, 8 mm) on the fracture properties of ASCCAC samples, using a normal distribution methodology and two proposed modified fracture models. The three-point-bending (3-p-b) test was performed on single edge notched specimens with two beam depths W approximate to 100 and 150 mm, different notch-to-depth ratios a = 0.1-0.7, and the same span/depths ratio S/W of 4. Results show that the average values of tensile strength f(t), fracture toughness K-IC and fracture energy G(F) can be determined from peak load P-max measurements based on the boundary effect model (BEM) and the improved maximum fracture load model (MFLM) by incorporating the average grain size G. The experimental scatters were analyzed based on the normal distribution analysis and the peak load P-max was reliably predicted with 95% reliability.