This post is first in a series covering different assessment methods for stability of masonry structures. This post covers classical and equilibrium methods; Part 2 covers suitable numerical modeling techniques as well as different examples of physical modeling for masonry stability.
The persistence of some of the oldest structures in the world in masonry has demonstrated the high potential for masonry structures to last through various conditions over long periods of time. Masonry’s compressive strength is extraordinarily high – it is estimated that a stone pillar would have to be 2 kilometers tall in order to fail by crushing.  As a result, in contrast to materials such as concrete and steel that make up most of present-day structures, the limit state of masonry is often dictated by its geometry and not its material properties.
Research into the stability of masonry structures is valuable for two main reasons. Firstly, this research enables us to understand and preserve the structures of the past. Many structures of rich cultural heritage are made of masonry, but their stability is challenged by environmental and anthropogenic threats, such as earthquakes or terrorist attacks. [2–6] The second reason is forward-looking. In some areas of the world, masonry materials are abundant and are thus the most economic choice of building material. An understanding of stability in masonry structures can make possible design tools for materially efficient structures.
Examples of masonry structures are given below. Philadelphia City Hall (1901) is the world’s tallest masonry structure at 167 meters height. [A] The King’s College Chapel (1515) in Cambridge, UK is not even a fifth of the height of Philadelphia City Hall, but the complex geometry of its fan vaults make it a compelling study of masonry stability. [B] Finally, the Armadillo Vault (2016) is a prime example of how an understanding of masonry stability can inform efficient design today. [C]
Methods and theories of structural analysis for masonry structures
The structural analysis of masonry arches and structures have preoccupied countless scientists since the 17th century. In this post, studies on 1. Classical methods and 2. Limit state analysis (including equilibrium analysis and kinematic analysis) are presented. A future post will explore 3. Numerical modeling and discuss existing studies that use each method to assess masonry structures. A more comprehensive overview of studies on each analysis method can be found in [7–9].