Multi-criteria parametric verifications for stability diagnosis of rammed-earth historic urban ramparts working as retaining walls

Abstract

Institutions such as ICOFORT (International committee on fortifications and military heritage) encourages the development of diagnosis strategies for the conservation and maintenance of historic earthen walls as highly necessary. Thus, it is important to be aware of the conditions in urban contexts, where the deterioration can be more aggressive and the risk of damage increases. Despite this, there are many strategies of constructive diagnosis for these kinds of monuments, but not many of them are concerned with the structural assessment of situations in which the ramparts work as a retaining wall in an unforeseen way. The medieval ramparts of Seville (Spain) are shown as a completely representative case study of the above-mentioned situation. In the research sector, the monument resists the lateral earth pressure developed by the new difference in height at both sides of the wall. Based on the limited states principle and on different international codes formulation, a tool was programmed to carry out automatic calculations to verify the case study’s overall stability conditions using standard sections. The obtained results were based on the overturning, bearing, and sliding overdesign factors (ODF) and determined a stable situation that could be at risk because of changes in the surrounding such as, excavations or the movements of the ground water table, or seismic events. Thus, the need and usefulness of strategies and control instruments that should be integrated into heritage intervention projects have been proved.