Earth fissures induced by water infiltration in collapsible loess: predictions based on a cantilever beam rotation failure mode

Collapse earth fissure is a common type of disaster in loess regions, where water infiltration is one of the primary factors that contributes to surface ruptures and uneven settlement. However, the research on the cracking behavior of collapsible loess under the action of water infiltration has been mainly qualitative, and there is a lack of quantitative analysis methods. In this study, through field survey, trench exploration, drilling and geotechnical engineering tests, we found that collapsible loess in Xibai Village subjected to an increased water content due to canal leakage presents a deformation and cracking failure mode similar to that of cantilever beam structure. Then, based on a simplified cantilever beam model and theory, a formula for predicting the location of initial cracks in collapsible loess caused by canal water leakage was derived using the material mechanics analysis method. The accuracy of the prediction was verified by comparing it with the results of field immersion tests, and the error was within 30%. In addition, considering the continuous expansion of the wetting zone, the theoretical formula for the location of fissure rupture propagation in collapsible loess in different seepage stages was then derived. This study provides a dependable analytical approach for estimating the extent and impact of earth fissures caused by the canal water leakage in collapsible loess areas, which can help to improve the security and stability of infrastructures in such areas.