Existing Damage

Four different types of alterations, visible in both buildings, are here highlighted and discussed:

1- Cracking in piers. Cracks exist in a few piers of Mallorca Cathedral and most piers of Santa Maria del Mar (Fig. 8). Vertical or oblique cracks have developed across the stone extending, in some cases, to several rows. They tend to concentrate close to the corners of the octagonal section (the less confined parts) and, in some cases, shape full wedges partially or totally detached from the core of the pier. In the case of Santa Maria del Mar, the cracks are related to additional forms of damage (black patina and crusting, superficial loss of stone and mortar at joints) which can be clearly associated with the severe fires experienced. The reason for similar cracks in a few piers of Mallorca, randomly distributed, is less clear.

2-Cracking in arches and vaults. In the lateral naves of Santa Maria del Mar, a longitudinal crack has developed following the keystones ofthe transverse arches (Fig. 8, right). The longitudinal cracks in the aisles are due to a differential settlement between the pier and the buttress. The arches do actually show the deformation and damage which should be expected from this type of settlement (Fig. 9, left). In a few cases, initial deformation appeared

Figure 8. Cracking in piers (Mallorca Cathedral, left, and Santa Maria del Mar, repaired, right).

Figure 7. Mallorca Cathedral's 4th bay construction sequence.

Figure 8. Cracking in piers (Mallorca Cathedral, left, and Santa Maria del Mar, repaired, right).

Figure 9. Aisle arches of Santa Maria del Mar. Deformation and cracking (left). Arch deformed due to accidental removal of centering causing expulsion of unhardened mortar (right).

due to an early or accidental removal of centering (Fig. 9, right) related, perhaps, to the fire of 1379.

3-Cracking in walls and façade. Cracking, mostly developed along the mortar joints, can be also recognized in the exterior or clerestory walls. It can be linked to the out-of-plumbing experienced by the façade in the case of Mallorca Cathedral and the façade clock-towers in Santa Maria del Mar.

4-Deformation. The deformation of the overall structure is perceptible in Mallorca Cathedral. The piers show significant lateral deformation reaching, in some cases, up to 30 cm, i.e., 1/100 of height at the springing of the lateral vaults. Remarkably, both the magnitude and the shape of the deformation vary very significantly (almost randomly) among the different bays, or even between the two halves of a single bay (Fig. 10). Conversely, the piers of Santa Maria del Mar show a more regular pattern both in direction and value, with maximum values ranging between 2 and 6 cm (8 cm in a single case), about 1/300 of the height at the springing of lateral vaults.

These deformations have been measured with respect to the ideal un-deformed geometry of the structure. For that purpose, the "ideal" profiles are reconstructed based on the information on original geometric parameters (radii, positions) which can be derived (or guessed) from the present geometry. All deviations due to construction defects, positioning errors, deformation of centering and plastic mortar settlement (among other possible effects) are ignored. Because of it, real deformations cannot actually be determined and the above measurements can only be understood as a coarse estimation. The possibility of the deformations mentioned for Mallorca Cathedral being mostly a consequence of errors and hazards experienced during the construction cannot be disregarded. The same applies to possible soil settlements estimated as a

Figure 10. Deformation of the bays of Mallorca Cathedral.

difference between architecturally related vertical references (such as opposite imposts, capitals or arch springings), whose unevenness might be due, at least in part, to construction inaccuracies.

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