Dr. Eng. Ahmed Elyamani

This research aims at throwing the light on one of the few survived examples of Ancient Egyptian vaulted structures; those are the storerooms of the temples of the Ramesseum and Sety I built in the 13th century BC. In the first case, only some of the adobe vaults and walls are still standing; whereas in the second case all the vaults collapsed and only the walls exist. Due to lack of maintenance and also scientific research on this topic, the survival remains may be lost forever. The research started with tracking the chronological development, the architecture and the construction of the adobe barrel vault in Ancient Egypt. The two case studies of the research were visually inspected and the existing damage symptoms and causes were reported and investigated. A structural analysis were carried out to understand the structural behavior and the causes of damage. Finally, a number of interventions were proposed that may help the existing ruins to survive.

The paper presents the current state of an on-going research aimed at characterizing the seismic response of Mallorca cathedral. Mallorca cathedral is an audacious Gothic structure built in the island of Mallorca during 14th-16th centuries, characterized for its large dimensions and slender structural members. So far, experimental and numerical modal analysis, in addition to tentative model updating and seismic analysis, have been performed. The dynamic identification tests have been carried out by ambient vibration testing, while the frequency domain decomposition (FDD) technique has been used to obtain the modal parameters. A 3D Finite Element (FE) model has been used to determine the vibration modes. The model has been updated by modifying some structural parameters to improve the matching between experimental and numerical modal parameters. Once updated, the model has been utilized to study the seismic response of the cathedral using non-linear static pushover analysis. Conclusions on the possible collapse mechanisms and the seismic performance of the structure are presented.

The paper presents the application of continuous dynamic monitoring and thermographic monitoring to the study of Mallorca Cathedral, one of the largest medieval structures built in Europe. The dynamic monitoring has been carried out by means of a network of three strong motion tri-axial accelerometers installed in December 2010. This network has allowed the capture of seven seismic events characterized by different epicenter locations and frequency contents. The post-processing of the information recorded during these events has provided significant insight on the cathedral dynamic response. The paper also presents the post processing of raw data of nine months of continuous dynamic monitoring, allowing the characterization of the effect of temperature changes on the natural frequencies of different mode shapes. A complementary study undertaken by thermographic monitoring, in which a part of the cathedral has been monitored for at least two weeks in summer and also in winter using an IR camera, is also presented. The relation between the stone masonry temperature of different structural elements (columns, vaults, arches, walls) and natural frequencies has been investigated. This study is part of a more detailed research, still in progress, aimed at investigating the seismic behavior and vulnerability of Mallorca Cathedral.