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The key concern of the study was the in situ assessment of cracks in historic masonry structures by quantitative IR thermography (QIRT). To better understand the potentials and/or limits of QIRT for that purpose, the non-destructive in situ survey composed of QIRT and ultrasonic testing was conducted on a sixteenth century monument, suffering from structural cracks that had occurred in recent years. Its aim was to discover the thermal behaviour and ultrasonic characteristics of cracks in relation to depth and moisture content. The superficial and deep cracks were found to have different thermal responses to exposed conditions which made them easily distinguishable by QIRT analyses. The results of thermal monitoring during the exposure of heating conditions were promising in giving hints of methods for the depth assessment of deep cracks in masonry. The in situ ultrasonic data taken in indirect transmission mode provided knowledge on the depth of cracks that enhanced the accuracy of the non-destructive in situ survey.

This study is focused on the improvement on the porous material characterisation, measuring the transition stage between the saturated and dry phases, which has been defined in literature as the critical moisture content (Θc). This study develops a procedure based on Quantitative IR Thermography (QIRT) determining the effective Θ c , as a physical property for the porous material. The Θc for San Marco bricks were examined in laboratory by QIRT and the standard gravimetric method (SGM). It was seen that QIRT can be used to determine the Θ c and was also found to be more practical and sensitive than the SGM. The results obtained in the laboratory were promising to give the hints of methods for quantitative moisture content measurements and in-situ QIRT investigations.

The key concern of this study is to discuss the reliable acoustical metrics for analyzing particular sound fields within monumental multi-domed sacred spaces with an emphasis on multiple sound energy decay formation. The potential of such structures in featuring non-exponential sound energy decay characteristics necessitates new formulation of sound decay indicators in understanding of their sound fields. The early and late energy decay components within non-exponential sound energy decays can have a unique contribution to the interior acoustic quality. These acoustical features can also provide the functional and spiritual acoustical needs of monumental sacred spaces. Süleymaniye Mosque and Hagia Sophia, two major monuments of Istanbul World Heritage Site, are examined in this regard. Field measurements are the main method of data collection. Over collected room impulse responses, relevant acoustical predictors including decay rates and decay times are computed by applying Bayesian decay parameter estimation. Analysis results disclose double or triple decay formations in both structures. Authors argue that, the detection of multiple sound energy decays in analyzed structures sets out a new vision for room acoustics studies of sacred spaces and for multi-domed monuments. Thus, implementation of new metrics, namely multiple slope decay parameters to replace classical room acoustics indicators, is recommended and discussed in light of the outcomes of this study.

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Süleymaniye Mosque, the central structure of one of the largest mosque complexes of the Ottoman Empire, has been and remains an inspirational edifice for many fields, including architectural acoustics and material science. Comprehensive studies are needed to assess the acoustic conditions of Süleymaniye Mosque in relation to its architectural elements, interior finish materials, and any changes which have occurred in acoustic comfort levels as a result of large-scale repairs the structure has been subjected to in its life time. In-situ acoustic tests were undertaken in 2013, immediately following final restoration work done between 2007-2011. These recent data were then compared to previously-published in-situ measurement data showing acoustic conditions in the Mosque after 1969 and 1980 restorations. Acoustic simulations were performed to represent and discuss activity patterns in the structure when full to capacity. As a result of architectural form-geometry and interior material factors, the acoustic field of the Mosque exhibited the presence of very high reverberation times in all field tests, especially at low frequencies. The Mosque was found to suffer from high background noise levels emanating from the mechanical systems introduced during the 2007-2011 restoration. This study also highlights the necessity for further investigations of the acoustic characteristics of burnt-clay pots and historical lime-based plasters. Both should be investigated further in order to scientifically prove their contribution to the acoustics of the Mosque and help to restore the structure's original acoustic comfort conditions.

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