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Masonry construction has been globally ubiquitous for centuries due to its significant compressive strength and diverse architectural potential. Despite this, masonry is vulnerable to lateral loads such as those produced by explosions. The 21st century has been marred by a growing trend and threat of terrorist incidents, many of which involve explosive detonations. These generate blast waves which transmit substantial specific impulse to masonry buildings, resulting in significant damage and hazard to the occupants and those nearby. This highlights the need for methods to assess masonry structural resilience and human hazard due to blast. Full-scale testing of masonry response to blast is challenging due to the need for a large testing site in tandem with high construction costs. The original contribution of this PhD has been to develop and experimentally benchmark a new scaling method for blast-loaded masonry built with commercially sourced materials. By adopting the concepts of dynamic similitude, a reciprocal scale factor can be applied to a reduced-scale (model) structure's density to replicate a full-scale (prototype) structure's lateral to vertical force ratio. Two model and prototype pairs were subjected to loading from 100kg TNT at two overpressures where results have shown that the models were able to qualitatively replicate the prototype cracking and collapse and quantitatively characterise the debris. This research has also examined blast flow and masonry response models via CFD and the Applied Element Method (AEM). CFD results demonstrated acceptable agreement with the blast trial. AEM solutions indicated an ability to model masonry cracking or debris generation, but results showed the need for additional work to develop a semi-rigid corner restraint to model both response phases sequentially. A series of future trials have been designed to test the scaling method with long duration, large impulse blasts. This trial data will permit further benchmarking of AEM to examine its predictive capabilities.

Therapists are differentially effective, a concept that has been termed ‘therapist effects’. Research has shown that therapist effects account for around 5% of the variability in outcomes of psychological therapy. However, there has been little research investigating whether such therapist effects are stable over time. A systematic review was conducted to provide a contemporary synopsis of therapist effects research. The review comprised 21 studies that focussed on therapist effects for outcomes, extending the most recent review of Baldwin and Imel (2013). Results found an average therapist effect of 5% which was in common with previous findings. New research areas included low intensity treatment settings and comparisons of different outcome measures. In order to investigate the stability of therapist effects over time, the research report analysed data from steps 2 (low intensity) and 3 (high intensity) of an Improving Access to Psychological Therapies service, comprising 12,949 patients and 141 therapists. Multilevel modelling was used to determine the therapist effect of the whole service over 40 months. Then, for five equal time periods, Markov chain Monte Carlo procedures compared therapist effects over time. Results found an overall therapist effect of 4.9% with no statistical difference between time periods. Therapist effects for step 2 of 2.9% and for step 3 of 4.9% were found. However, such effects were not statistically stable over time. Further studies with higher patient and therapist sample sizes are recommended.

The transient dynamic response of annealed glazing to blast loading is a complex phenomenon dependent upon explosive proximity, glazing material properties and structural arrangement. With positive pressure durations in excess of 100ms, long-duration blasts produce substantial impulse and dynamic pressures. Annealed glazing accounted for ~90% of UK building glass at the end of 20th century with similar levels of utilisation the world over. As a brittle material, it cannot undergo plastic deformation resulting in sudden failure under tension. As the minimum level of glazing resistance to blast, annealed glazing breakage introduces significant hazard to a building’s occupants and those in surrounding regions. The original contribution of this PhD has been to investigate and quantify annealed glazing response to long- duration blast with an emphasis on the influence of structural arrangement via variable glazing thickness, area, aspect ratio and edge support conditions. Eighteen full-scale blast trials were conducted where results have shown that notionally elastic supports can prevent glazing breakage versus rigidly clamped arrangements. Edge conditions were also found to exert an important influence on both fragmentation and potential fragment hazard with elastic supports shown to produce large, angular fragments versus rigid arrangements which generated significant cracking and smaller fragments. The quantification of peak panel deflection, breakage time and applied breakage impulse has demonstrated significant variability with the influence of edge supports and aspect ratio found to be dependent on proximity to a threshold area for a particular thickness. This research has also examined computational models of glazing response and blast wave propagation produced with the Applied Element Method (AEM) and CFD. Comparisons with experimental data have shown reasonable levels of agreement, indicating the potential to provide future predictive capacity.