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IntroductionThe Gothic vault is a common feature of many large medieval churches, abbeys and cathedrals across western Europe. Superseding the earlier barrel vault, the Gothic cross vault incorporates a pointed arch profile and ‘ribs’, demonstrating the skill of the masons of the time. Unlike the barrel vault which distributes its load uniformly along the transverse walls, the load paths of the Gothic cross vault converge in the springings at each corner of the vault. This allows for clerestory openings in the upper structure, which maximise the amount of light that can enter the space within.
Problem Statement
A lack of understanding of this highly complex structure has led to many churches experiencing severe deformation and, in some cases, fatal collapse (e.g. Holyrood Abbey). The predominant cause of failure is lateral instability due to insufficient resolution of the outward thrusts of the roof and vault (Theodossopoulos & Sinha, 2008). A better understanding of the failure modes is essential in order to implement effective, unobtrusive conservation solutions that will improve the stability of the overall structure.
Cases of collapse such as Holyrood Abbey have shown that lateral instability in the upper structure causes outward deformations at the top of the lateral wall, and inward at the bottom. The effect of the instability upon the aisle vaults can thus be simulated as a displacement of the abutments (Theodossopoulos et al, 2003). This thesis aims to build on Dr. Theodossopoulos' PhD research of 2001 investigating the collapse modes of the Gothic vault, and hence determine the safe limits of certain parameters such as lateral deformation. The research aspirations section provides a detailed outline of our aims and objectives. We will use Dr. Theodossopoulos' quarter-scale model of an existing quadripartite vault in Holyrood Abbey, which we will assemble, construct, and test under various loading conditions. This will involve conducting both elastic loading tests and a test to failure by spreading the abutments. Repair work will also be attempted to alleviate the effects of plastic crack formation. The results from this investigation will help to further modern-day understanding of the behaviour of Gothic vaults, which is relevant for the conservation of structures still existing throughout Britain. |
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© 2013 James Sanderson and Michael Scott | All rights reserved.
School of Engineering, College of Science and Engineering, University of Edinburgh
© 2013 James Sanderson and Michael Scott | All rights reserved.
School of Engineering, College of Science and Engineering, University of Edinburgh