In the planning process for high rise buildings, it is common practice to carry out physical or numerical simulations of the wind flow around such buildings, in order to establish the acceptability or otherwise of these wind conditions for a range of pedestrian activities such as sitting, slow walking, rapid walking etc. It is less common to assess the wind conditions in terms of pedestrian safety in high winds, and the safety of cyclists and light high sided vehicles is never usually considered. The need for such considerations has become tragically obvious in a recent incident in Leeds, where a pedestrian was killed after a lorry blew over due to winds around a new high rise structure. When pedestrian safety is considered, this is usually in terms of a simple wind speed criterion that does not take into account human behaviour and does not allow for a proper risk analysis. This project will consider these issues with a view to establishing a robust methodology for calculating the risk of a pedestrian, cyclist or high sided vehicle accident in high wind conditions around high rise building. Full scale measurements will be carried out around a high rise building on the University of Birmingham campus to measure the turbulent nature of the flow around such buildings, since it is these highly turbulent flows that are of relevance to the issue of safety rather than the mean wind flows. Wind tunnel tests and CFD calculations will be carried out of the same building to assess the adequacy of these techniques for predicting the highly turbulent flows of relevance to the problem under discussion. Trials will then be carried out using instrumented volunteers of a range of age and size, who will walk or cycle around the structure during windy periods, and their behaviour will be assessed both quantitatively and qualitatively, in order to develop probability distributions of the wind speed at which incipient instability of pedestrians occurs. In addition measurements will be made of the cross wind forces on scale models of typical high rise vehicles using the University of Birmingham moving model TRAIN rig, with highly turbulent cross wind conditions, again to develop probability distributions of wind speeds for incipient instability. The probability distributions thus obtained will then be used, with wind speed probability distributions, to develop a calculation methodology to determine the variation of accident risk around high rise structures.

As we increase the air tightness of our buildings in line with more stringent building regulations it is vital to specify adequate fresh air ingress to all occupied spaces to ensure the health and well-being of occupants. In order to optimise buildings for energy and health it is important that we have a comprehensive understanding of the dynamics of indoor air flow, which is complicated by the impact of human behaviour. Current knowledge of how humans interact with their environment and implications for the airflow within buildings is virtually non-existent. This proposal aims to develop facilities for investigating the detailed fluctuations of air movement due to occupants opening and moving through doorways. This will have a significant impact on the understanding of contaminant transport and fresh air ingress into buildings; it will also have implications for ventilation specification and simulation as well as building energy prediction.

Masonry construction, including both clay bricks and concrete blockwork, relies on 10 mm mortar joints to bond the units together. In the UK around 50 million m2 (wall area) of fired clay bricks and 60 million m2 of concrete blocks are produced every year, requiring around 1.5 billion litres of mortar. The functions of mortar in masonry construction are to provide an even bed between units, bond units together to provide flexural strength and seal joints against rain penetration. Increasingly the construction industry is realising that hydraulic lime mortars fulfil these requirements extremely well. One significant benefit of lime mortars, in comparison with more widely used cement mortars, is a 40% reduction in carbon dioxide emissions, a significant greenhouse gas.The proposed work is to develop low-energy high-performance mortars using a novel quicklime drying technique for the aggregates, the inclusion of admixtures with the mix and the extension of the binder phase to include pozzolanas and alternative low energy cements. This proposal aims to investigate and develop the use of quicklime addition to the fine aggregate as the means to dry the sand. The approach relies upon both the chemical combination of water to yield calcium hydroxide and the associated heat production. However, the amount of quicklime required will vary with sand moisture content and desired mortar mix. As the mortar mix designs become leaner (lower strength), increased quantities of quicklime will be required to dry the sand. The leanest mixes will require significant quantities of quicklime with an associated reduction in the hydraulic lime component. This will limit the potential engineering properties of the mortar unless modifications are made to its composition. The study will therefore investigate possible modifications, including the use of admixtures such as water reducers, pozzolanas, as well as more energetic hydraulic binders such as Roman cement. Current editions of the structural design codes for masonry do not include design data for lime mortared masonry. In combination with the development of low-energy mortars, the proposed work will seek to address this lack of data.The proposed research methodology comprises experimental investigation of dry mix low-energy mortars, including the study of efficiency of lime slaking to dry wet sand during the mixing process, micro-structural analysis of mortars, and investigation of low energy mortared masonry properties. Experimental studies will be supported by numerical analysis of masonry properties and comparative life cycle analysis of masonry. Research of sand drying and mortar properties will primarily be undertaken at the Universities of Bradford and Bristol, whilst experimental and numerical investigation of masonry properties and life cycle analysis will primarily be completed at the University of Bath. The current proposal extends previous work in two important areas: firstly it will extend the range of available low energy mortars; and, secondly, the proposed work will examine the performance of these limes in structural masonry so that engineers, architects and builders can use the material with confidence.

Masonry construction, including both clay bricks and concrete blockwork, relies on 10 mm mortar joints to bond the units together. In the UK around 50 million m2 (wall area) of fired clay bricks and 60 million m2 of concrete blocks are produced every year, requiring around 1.5 billion litres of mortar. The functions of mortar in masonry construction are to provide an even bed between units, bond units together to provide flexural strength and seal joints against rain penetration. Increasingly the construction industry is realising that hydraulic lime mortars fulfil these requirements extremely well. One significant benefit of lime mortars, in comparison with more widely used cement mortars, is a 40% reduction in carbon dioxide emissions, a significant greenhouse gas.The proposed work is to develop low-energy high-performance mortars using a novel quicklime drying technique for the aggregates, the inclusion of admixtures with the mix and the extension of the binder phase to include pozzolanas and alternative low energy cements. This proposal aims to investigate and develop the use of quicklime addition to the fine aggregate as the means to dry the sand. The approach relies upon both the chemical combination of water to yield calcium hydroxide and the associated heat production. However, the amount of quicklime required will vary with sand moisture content and desired mortar mix. As the mortar mix designs become leaner (lower strength), increased quantities of quicklime will be required to dry the sand. The leanest mixes will require significant quantities of quicklime with an associated reduction in the hydraulic lime component. This will limit the potential engineering properties of the mortar unless modifications are made to its composition. The study will therefore investigate possible modifications, including the use of admixtures such as water reducers, pozzolanas, as well as more energetic hydraulic binders such as Roman cement. Current editions of the structural design codes for masonry do not include design data for lime mortared masonry. In combination with the development of low-energy mortars, the proposed work will seek to address this lack of data.The proposed research methodology comprises experimental investigation of dry mix low-energy mortars, including the study of efficiency of lime slaking to dry wet sand during the mixing process, micro-structural analysis of mortars, and investigation of low energy mortared masonry properties. Experimental studies will be supported by numerical analysis of masonry properties and comparative life cycle analysis of masonry. Research of sand drying and mortar properties will primarily be undertaken at the Universities of Bradford and Bristol, whilst experimental and numerical investigation of masonry properties and life cycle analysis will primarily be completed at the University of Bath. The current proposal extends previous work in two important areas: firstly it will extend the range of available low energy mortars; and, secondly, the proposed work will examine the performance of these limes in structural masonry so that engineers, architects and builders can use the material with confidence.

A Fire Safety Strategy is an essential component of the design for a building. It ensures that in the event of a fire, building occupants can be evacuated safely. The main consideration in these strategies is time. The engineer must show that all occupants can evacuate the building without being exposed to the fire. This is particularly difficult in the case of tall buildings where occupants must travel long distances downward before they can exit the building. A rule of thumb to estimate total building evacuation time is one minute per floor. By this rule the 828m, 162 floor Burj Khalifa in Dubai would take more than 2.5 hours to fully evacuate. The 159m, 31 storey TVCC tower in Beijing was engulfed in a fire which spread up the entire height of the building within 15 minutes of ignition. Clearly, it would not have been possible to evacuate occupants in sufficient time to save them from this fire. It is therefore necessary to have a specific Fire Safety Strategy for these unique buildings.Firstly, the fire must be prevented from spreading vertically, confined to one floor for as long as possible, so occupants on floors far enough from the fire can remain safely in the building until the fire is extinguished or runs out of fuel. Secondly, the building must remain standing, again so that people still in the building and the emergency responders that enter it to fight the fire do not perish as in the World Trade Center disaster. Thirdly, the vertical escape routes must remain structurally intact and smoke free to allow safe passage of occupants from the building. If occupants cannot reach the outside of the building in a timely fashion, then the vertical escape routes must act as the outside and once reached, guarantee safety. To provide these three crucial elements and ensure the safety of occupants of tall buildings, designers must be able to approximate in a quantitative manner the fires expected to occur in these buildings. With optimal use of space being the driving force behind these designs, floors often consist of large, open plan compartments. According to the CTBUH, 82% of the tallest 100 buildings are partially or completely office use (62% completely). Fires in large open plan spaces tend not to cover the entire area of the compartment at any instant but instead propagate across it. These fires have been labelled "travelling fires" and given the statistics, it should be expected that these would be typical fires for tall buildings. Despite this, current methods of prescribing fires are based on data obtained with small homogeneously heated 4mx4m (approx) compartments. These methods, used since the beginning of the 20th Century, are still applied to all structures irrespective of their nature.Current state-of-the-art research shows that a realistic definition of the fire is essential to safely provide all three critical components of the Fire Safety Strategy but also that our current analytical and computational tools cannot provide this. This means we cannot provide an adequate quantitative assessment of the Fire Safety Strategy for tall buildings. Designers are thus not capable of assessing if safety measures introduced result in an under or over dimensioned building. Given the level of optimisation required for tall buildings, this is clearly an important weakness in the design process. As large-scale fire testing cannot be done for all possible building configurations, safe designs can only be achieved using properly validated tools. With no sufficiently detailed test data, fire models cannot be said to have been performance assessed, verified and validated for these scenarios. Real data is needed to establish modelling capabilities and identify problems, thus an integrated modelling/testing programme is essential. This project will conduct a series of tests and modelling studies to establish a methodology that generates real fire inputs for the safe definition of a Fire Safety Strategy for tall buildings.