There is an urgent need for design research in landscape architecture to enable the development of a Design Guide for biodiverse green spaces in prisons, which will be safe for prisoners to access. As the second largest government estate, the Ministry of Justice of England and Wales (hereafter MoJ) has a total land holding of >3000 hectares[1], of which 65% is within its prisons portfolio[2]. Despite the significant extent of this estate, for reasons of security and cost, much of the land 'inside the wire' of individual prisons is characterised by tarmac and hard landscaping. Where green spaces exist, these are often closely-mown lawns offering limited wildlife habitats. Recognising these shortfalls, MoJ lists biodiversity as a strategic focus, and has recently established a biodiversity baseline, a natural capital assessment tool, and a nature recovery plan for the estate which seeks to substantially improve biodiversity, wellbeing, and other ecosystem services such as carbon sequestration and flood alleviation[3]. In addition to these biodiversity and sustainability aspirations, a growing evidence base shows that green spaces in prisons significantly enhance the wellbeing both of prisoners and of the staff who supervise them.[4] Recent research has shown lower levels of self-harm, violence and staff sickness absence in prisons with more green space. There is clearly both an important opportunity here to enhance biodiversity and wellbeing within a significant proportion of government estate, and commitment to this goal at a senior level. However, genuine operational concerns - that green spaces present security risks when accessed by the incarcerated people who derive benefit from them - hamper progress. Specifically, it is feared that contraband may be concealed in vegetation, weapons furnished from natural materials, and that vegetation may obscure the clear sightlines that are important for security. Both in the development of new prisons, and in any redevelopment of existing prisons, these concerns tend to stifle the introduction of green spaces in any form other than lawns. Design research needs to be applied here: prisons are very expensive to build, and since landscaping is almost the final stage of construction, the lack of clear and costed landscape designs that meet the demands of security means that landscaping for biodiversity and wellbeing is often 'value-engineered' out of construction plans altogether. At best, a lawn is laid, but often tarmac prevails. Working with project partners the Ministry of Justice and prison-building contractor Kier, we will produce a Design Guide for green spaces in prisons applicable across the UK and beyond. Its utilisation will directly support enhanced biodiversity across a significant proportion of the public estate, and with it the wellbeing of those who live and work in prisons. Ultimately, the intention is that the Design Guide will become part of the Technical Standards for prison construction, both mandating biodiverse green spaces in all new UK prisons, and providing a blueprint for their design.

Key to the survival of a building subjected to extreme loads, such as fire, blast and impact is the provision of a robust structural frame, which can accommodate the resulting high strength and ductility demands. To this end, the performance of the beam-to-column joints is paramount, since these will be subjected to high rotation capacity demands and high tying forces, as they are required to facilitate catenary action and provide an alternative load path in the case of a sudden failure of a supporting column. The fundamental hypothesis underpinning this research project is that replacing the carbon steel components in critical parts of the joints (e.g. bolts, angle cleats, plates) with an appropriate grade of stainless steel, which has greater ductility, as well as better fire behaviour, will enhance the joint strength and ductility thus maximizing the resistance to a progressive collapse during an extreme event such as an impact, blast or fire. The project consists of 4 technical work packages with a fifth one dedicated to impact and dissemination, as outlined hereafter: WP 1 focuses on the behaviour of joints under impact loading. Stainless steel plate, bolt and weld material coupons will be tested under high strain rates to determine the material response under conditions brought about by impact loading. The obtained results will be utilised to calibrate material models explicitly accounting for strain rate sensitivity as well as fracture models considering the effect of strain rate and stress triaxiality. Furthermore, lap joints and T-stubs will be tested at high strain rates and FE models will be developed and utilised in parametric studies WP2 studies the behaviour of material and connections at and after exposure to high temperatures ranging from 20 to 1000 degrees centigrade. Isothermal and anisothermal material coupon tests will be conducted on plate, weld and bolt material, whilst for the post fire condition, both air cooling and quenching will be considered. Upon determining the effect of temperature on material response, advanced FE models will be developed to establish the performance of double web cleat, top and seat angle cleat and extended endplate joints under and post fire conditions. WP3 investigates the behaviour of individual joints under moment and shear and double sided joints under moment, shear and tension under static and dynamic loading conditions. Both physical tests and numerical models (utilising the findings of WP1) will be generated to characterise the joint response under realistic column loss scenarios. Supplementary numerical studies on geometrically identical conventional steel joints will also be conducted to compare the performance of the novel hybrid carbon/stainless steel and conventional steel joints. WP4 will utilise all previous WPs to develop and calibrate spring joint models suitable for incorporation into FE simulations of frames using beam elements. Using OpenSees, low-, medium- and high-rise 3D steel frames employing the novel hybrid joints as well as conventional ones will be analysed under a variety of extreme hazard scenaria including impact and fire using a probabilistic approach for the variability in material, geometry and loading. The obtained results will be utilised to determine the probability of failure and derive analytical fragility curves and quantify the effect of the adoption of the novel connections on the survivability of steel framed structures. Finally, WP5 will utilise all previous WPs to develop and disseminate design guidance to maximise the impact of the research. The close collaboration with leading consultants and strong links with BSI, as well as the applicants' close familiarity and involvement with Eurocode 3 will guarantee prompt dissemination of the research findings to the relevant practices, institutions and code development bodies.