Assessment of Safety of Masonry Buildings near Deep Excavations: Ultimate Limit States

Abstract

It is a common practice to construct new buildings in the close vicinity of existing buildings. New buildings require deep excavations, which cause non-uniform displacement of the ground, causing a negative impact on the safety and technical conditions of adjacent buildings, including masonry buildings. The fundamental condition to verify structural safety is the knowledge of impacts and the load-bearing capacity of non-strengthened or strengthened structures. Safety is provided via strengthening the structure against deformations related to the ground displacement or by reducing non-uniform displacements of the building structure. This paper focuses on strengthening the ground and underground parts of masonry buildings. It also describes general requirements for providing safety of buildings according to the standard Eurokode 0 and the simplified method for protecting building structures with the use of steel tie rods. Based on the design methods for masonry structures specified in Eurocode 6 and the know-how of the authors in the field of protecting buildings in mining areas, the original method was proposed to determine the required area of reinforcement in the form of steel rods. Also, the original methods were introduced to verify ULS for inclined walls primarily under vertical load and shearing of pillars between openings. In addition to these analytical methods, this paper also illustrates methods for strengthening the ground and underground parts of masonry buildings. Presented in this paper, original solutions used to determine the strengthening of masonry structures and original models used to verify ULS for deflected walls primarily under vertical load can be directly employed in the design practice. The standard criteria were applied and the effects of building deflections, which are not specified in Eurocode 6, were considered.