Reliability-Based Correction of Collapse Settlement for Hydraulic Structures on Loess

Abstract

Using a single mean collapse strain can misrepresent settlement in spatially variable loess foundations, potentially leading to unsafe hydraulic-structure design and settlement-induced damage. This study examines an archival empirical correction classified by ground and structural conditions. Engineering-geological records from 12 sites informed the factor classification, and monitored settlements of seven irrigation structures were used for validation. The resulting composite factors range from 1.30 to 1.44 across the specified ground and structural classes. For the seven field cases, the corrected predictions achieved a mean absolute percentage error of 12.7%, compared with 35.2% and 32.4% for the two conventional calculation sets. Archival physical-model observations independently supported the proposed load-redistribution mechanism. The correction provides a transparent way to account for ground variability and structural response in preliminary and design-stage settlement assessments, provided that representative collapse-strain data and a defined wetting scenario are available.