a b s t r a c tThe vulnerability of the masonry envelop under blast loading is considered critical due to the risk of loss of lives. The behaviour of masonry infill walls subjected to dynamic out-of-plane loading was experimentally investigated in this work. Using confined underwater blast wave generators (WBWG), applying the extremely high rate conversion of the explosive detonation energy into the kinetic energy of a thick water confinement, allowed a surface area distribution avoiding also the generation of high velocity fragments and reducing atmospheric sound wave. In the present study, water plastic containers, having in its centre a detonator inside a cylindrical explosive charge, were used in unreinforced masonry infills panels with 1.7 m by 3.5 m. Besides the usage of pressure and displacement transducers, pictures with high-speed video cameras were recorded to enable processing of the deflections and identification of failure modes. Additional numerical studies were performed in both unreinforced and reinforced walls. Bed joint reinforcement and grid reinforcement were used to strengthen the infill walls, and the results are presented and compared, allowing to obtain pressure-impulse diagrams for design of masonry infill walls.

The strain rate effect influences the mechanical properties on most construction materials and its investigation is critical for structural engineering. Current materials such as steel or concrete have been intensively investigated. However, similar studies on the dynamic properties of masonry or masonry components such as clay brick or mortar are scares. This work intends to study the behavior of masonry and its usual components (clay brick and mortar) when subjected to high strain rates. A Drop Weight Impact Machine is used at different heights and weights introducing different levels of strain rate. Empirical relations of Dynamic Increase Factors (DIF) are derived from the experimental results and the strain rate effect on compressive strength, compressive fracture energy, strain at peak strength and Young's modulus are determined and presented.

Fibre Reinforced Polymers have become a popular material for strengthening of masonry structures. The performance of this technique is strongly dependent on the bond between the FRP and the substrate. Understanding the strain rate effect on these materials and strengthening techniques is important for proper design and proper modelling of these systems under impacts or blast loads. This work aims to study the behaviour of the bond between GFRP and brick at different strain rates. A Drop Weight Impact Machine specially developed for pull-off tests (single shear tests) is used with different masses and different heights introducing different deformation rates. The strain rate effect on the failure mode, shear capacity and effective bond length is determined from the experimental results. Empirical relations of dynamic increase factors (DIF) for these materials and techniques are also presented.

The design of stiffened, composite wing panels must satisfy a range of requirements related to performance, economy and safety. In particular, the design must be damage tolerant to satisfy a number of different performance requirements for various states of damage. To obtain an optimum configuration that satisfies these requirements simultaneously, optimization code PANOPT was extended with a multi-model capability. First, the effect of damage tolerance constraints on postbuckled optimum design was established for blade-I-and hat-stiffened panels with stiffener flanges embedded in the skin. The "classical" order of efficiency for optimized panels designed for buckling alone (hats, I's, blades) was no longer valid, as the masses of the three panel types were approximately equal. To obtain realistic damage models, the failure mechanismms and damage tolerance of the panel concept with embedded stiffeners were determined in an experimental programme. Finally, the multi-model capability of PANOPT was demonstrated with the simultaneous optimization of an undamaged panel carrying design ultimate load, the same panel with a separated stiffener carrying design limit load, and the panel with a cut stiffener carrying seventy percent of the design limit load. An optimum design was found with an additional mass of only five percent compared to a panel optimized for the undamged case alone.

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