Fracture and Damage Analysis of Cement-Stabilized Fine and Coarse Grain Soils Under Static and Cyclic Loading Using Chevron-Notched SCB Specimen

Abstract

Fracture toughness and cohesive fracturing properties of two classes of sandy-clay soils, (A) with fine and (B) coarse grains and stabilized with low (2%) and high (10%) cement (as soil stabilizer), were investigated using a chevron-notched semicircular bend (CN-SCB) sample under static and cyclic loads. The samples with coarser grains and higher amounts of cement stabilizer showed higher KIc compared to the soils containing low cement and fine grains. A noticeable reduction in KIc was also observed under cyclic loading compared to the monotonic loading. Load-crack opening displacement (COD) graphs obtained during cyclic loading showed high plastic deformation accumulation before the final fracture. The cycles required for the fatigue crack growth of the Class A soil were noticeably (three to six times) higher than the Class B. The FRANC2D nonlinear simulations, cohesive fracture analyses, and maximum stress theory were utilized for estimating the critical crack length and the onset of cohesive unstable crack propagation.