Structural Assessment of a Water Reservoir Masonry Vaulted Roof from the Nineteenth Century

Abstract

This article presents an experimental and numerical study on the structural safety of an old buried water reservoir built in the second half of the nineteenth century. The main goal of the study was to assess the feasibility of changing the reservoir roof from a garden with limited access to an outdoor exhibition or concert area, with an increase in service loads. The reservoir comprises a set of cylindrical vaults, built with rubble masonry and lime mortar, supported by a set of stone masonry arches and columns. Because no original design elements exist, the following methodology was followed: (1) a structural survey was first carried out for geometrical and material identification and for assessment of anomalies; (2) core samples were extracted from the vaulted roof to characterize the material properties of the rubble masonry and lime mortar; (3) a three-dimensional (3D) nonlinear finite element (FE) model of the structure was developed and used for structural safety verification; and (4) an in-situ static load test was carried out, in which the roof was subjected to a uniformly distributed load for assessment of its structural response and to validate the results from the numerical model. Overall, this study showed that the vaulted roof of the water reservoir has sufficient load capacity for its future use. Moreover, this work illustrates the application of a comprehensive methodology to assess the structural safety of a historical and very particular type of construction.