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Results of full scale measurements of the dynamic characteristics of a steel lighting tower at the Sydney Cricket Ground in New South Wales, Australia, are presented. The first three natural frequencies of vibration were found to be 0.50 Hz, 2.40 Hz and 4.84 Hz respectively; the corresponding mode shapes have also been determined. These results are compared with those obtained from a plane rigid frame dynamic analysis computer program and found to be in good agreement. Damping levels (in % of critical) were found to be approximately 0.3%, 0.8% and 1.0% for the first three modes.

Wind tunnel tests were conducted to investigate the effects of some aerodynamic devices on the wind‐induced responses of tall buildings and structures. It was found that the fitting of small fins or vented fins to a square tower caused an increase in the along‐wind response, while reduction in cross‐wind response occurred only for a limited range of reduced wind velocities. The use of slotted corners resulted in significant reductions in both the along‐wind and cross‐wind responses over an extended range of reduced wind velocities. The concept of slotted corners is practical and could be useful in the design of modern tall buildings and structurees.

Wind tunnel model tests were conducted to investigate the effect of building shape on the wind-induced response of a tall building with a rectangular cross-section. It was found that horizontal slots, slotted corners and chamfered corners caused significant reductions in both the along-wind and cross-wind responses. The wake spectra, probability distributions of the responses, and the along-wind and cross-wind force spectra were examined to determine the cause for these changes in response characteristics.

Procedures for analysis of environmental wind conditions at the site of a proposed building, using mean annual maximum wind data and wind tunnel model testing are discussed. NEWMED I, the Clinical Sciences Building of the University of Newcastle, which is situated at the Royal Newcastle Hospital, is used as an exam pie. Wind data indicated the wind tunnel testing from the S and WNW directions would be adequate to describe the environmental wind conditions at NEWMED. Testing indicated unacceptably high annual maximum wind gusts under southerly flow at the exposed southern end of the building, the majority of ground level locations, and in Reids Park, despite a wind break in the latter area. Under WNW flow, strong winds occurred at both ends of the building and close to Reids Park. Suggestions are made to minimize the effect of the strong winds to maximise human comfort.

The enhanced dynamic response of a tall square building under interference excitation from neighbouring tall buildings has been studied in a series of wind-tunnel model tests. In a low-turbulence wind environment and under normal strong wind conditions, the dynamic loads on the upstream of an identical pair of tall buildings may increase by a factor of up to 4.4. The dynamic loads on the downstream building of the pair may increase by a factor of up to 3.2 due to “resonant buffeting”. Measurements of along-wind and cross-wind force spectra and a number of wake spectra provide an explanation for the observed behaviour. Possible excitation mechanisms are discussed and critical building arrangements presented. The large interference loads found in this study indicate that interference excitation should be carefully considered in the design of tall buildings.

Australian railway networks possess a large amount of aging timber components and need to replace them in excess of 280 thousands m3 per year. The relatively high turnover of timber sleepers (crossties in a plain track), bearers (skeleton ties in a turnout), and transoms (bridge cross beams) is responsible for producing greenhouse gas emissions 6 times greater than an equivalent reinforced concrete counterparts. This paper presents an innovative solution for the replacement of aging timber transoms installed on existing railway bridges along with the incorporation of a continuous walkway platform, which is proven to provide environmental, safety and financial benefits. Recent developments for alternative composite materials to replace timber components in railway infrastructure construction and maintenance demonstrate some compatibility issues with track stiffness as well as structural and geometrical track systems. Structural concrete are generally used for new railway bridges where the comparatively thicker and heavier fixed slab track systems can be accommodated. This study firstly demonstrates a novel and resilient alterative by incorporating steel-concrete composite slab theory and combines the capabilities of being precast and modulated, in order to reduce the depth, weight and required installation time relative to conventional concrete direct-fixation track slab systems. Clear benefits of the new steel-concrete composites are the maintainability and constructability, especially for existing railway bridges (or brown fields). Critical considerations in the design and finite element modelling for performance benchmarking of composite structures and their failure modes are highlighted in this paper, altogether with risks, compatibilities and compliances.

We present recent multidisciplinary research conducted by psychologists, engineers and physiologists investigating the effects of wind-induced building motion on wellbeing, manual task performance and cognitive performance. In a sample of actual office workers, we show that sopite syndrome is the main consequence of exposure to wind-induced building motion. Sopite syndrome, a form of mild motion sickness characterized by drowsiness and low motivation, is the main cause of reductions in work performance. Experimental research shows that biomechanical properties of the human body are influenced by the frequency of motion, which amplifies body sway and interferes with task performance at 0.5 Hz, and to a greater extent with increases in acceleration. Exposure to motion induced sopite syndrome in some participants, who performed significantly worse than unaffected individuals. A new generation of serviceability criteria should aim to minimize sopite syndrome, motion sickness, motion induced body sway, and other psychological and physiological factors, rather than only address perception thresholds, which will likely allow engineers and designers to create a new generation of buildings that will ensure an improved level of comfort and performance for building occupants.