Experimental and numerical investigation of the stability of overhanging riverbanks

Cantilever failure investigations for cohesive riverbanks

“…After that, cantilever failure occurred along the tension crack line. The dominant failure mechanism was observed to be beam failure, which is consistent with the findings of previous researchers who have suggested that beam failure may be prevalent (e.g., Darby et al, 2007;Samadi et al, 2011Samadi et al, , 2013Thorne and Tovey, 1981). Moreover, the results indicate that cohesive riverbanks with higher silt-clay contents are more susceptible to failure than those with lower silt-clay contents.…”

“…The dimensions of the failure block were 2·97-9·98 cm wide and 11·76-62·14 cm long (see Table 2). In terms of cantilever failure mechanisms, the experimental results are consistent with previous experiments, showing that beam failure is the dominant failure mechanism (Nardi et al, 2012;Samadi et al, 2013).…”

“…A couple of large-scale experimental studies on the failure mechanism of cantilevers have been reported recently. Taghavi et al (2010) conducted experiments to estimate the failure plane angle and tension crack depth, and Samadi et al (2013) carried out experimental studies to investigate dominant cantilever failure mechanisms, finding that beam and tensile failures are dominant. Moreover, Nardi et al (2012) conducted experiments to investigate mass failures in a sandy gravel riverbank and showed the occurrence of a variety of failure processes such as cantilever, slab and slide failures.…”

“…The results showed that the overhanging block dimensions and the cohesive force are highly significant for an analysis of cantilever stability (Samadi et al, 2011). A stress-strain behaviour model for a cantilever failure was also applied to simulate the subsequent failure of an overhanging block (Samadi et al, 2013). However, these previous studies have limitations in coupling fluvial erosion with cantilever failure and simulations coupling fluvial erosion and cantilever failure therefore need to be conducted.…”

“…Experimental limitations were the effect of scale and the friction factor between the cohesive riverbanks and experimental wall. The experiments were conducted at a smaller scale than the prototype because it was hoped to obtain cantilever failure information in expected patterns of response more rapidly and with a closer control over the model details than would be possible using a full-scale experiment (Muir, 2004;Samadi et al, 2013).…”