There is an increasing use of the discrete element method (DEM) to study cemented (e.g. concrete and rocks) and sintered particulate materials. The chief advantage of the DEM over continuum based techniques is that it does not make assumptions about how cracking and fragmentation initiate and propagate, since the DEM system is naturally discontinuous. The ability for the DEM to produce a realistic representation of a cemented granular material depends largely on the implementation of an inter-particle bonded contact model. This paper presents a new bonded contact model based on the Timoshenko beam theory which considers axial, shear and bending behaviour of the bond. The bond model was first verified by simulating both the bending and dynamic response of a simply supported beam. The loading response of a concrete cylinder was then investigated and compared with the Eurocode equation prediction. The results show significant potential for the new model to produce satisfactory predictions for cementitious materials. A unique feature of this model is that it can also be used to accurately represent many deformable structures such as frames and shells, so that both particles and structures or deformable boundaries can be described in the same DEM framework.

This paper presents a solar energy-based cooking solution for reducing the dependency of refugees on firewood for cooking food. The use of firewood is associated with a variety of problems such as deforestation, environmental degradation and household air pollution. This paper proposes that a collapsible parabolic solar cooker with 12 panels and a phase change material-incorporated cooking pot is a viable alternative to firewood. The phase change material allows food cooked during the day to be kept warm and subsequently consumed as an evening meal. Furthermore, the proposed solution considers, and fits within, the cultural aspect of the refugee context. The cultural aspect is highlighted as it is a factor in determining whether refugees will accept the proposed solution. This paper also presents a cost-benefit analysis of the proposed solution which shows that if used by a family unit of four members, the payback period is 52 weeks or less. Finally, this paper concludes with recommendations pertaining to the efficiency of the system to reduce cooking time and enable the system to keep food warm for subsequent meals. These recommendations are focused on maximising the chances of acceptance of the parabolic solar cooker by refugees during humanitarian crises.

The capital cities of the South Pacific are experiencing rapid urbanisation pressures as increasing numbers of people migrate to the primary cities either in search of employment and greater access to healthcare and education, or as a consequence of environmental ‘push’ factors. However, the limited capacity of municipal Governments to respond to the scale and pace of change is leading to a growth of informal settlements in peri-urban locations. Factors of exposure, sensitivity, and adaptive capacity combine to make these informal settlements the most vulnerable areas to natural hazards. In response to this critical urban resilience agenda, this paper looks at how participatory action research is providing inter-disciplinary scientific support for the implementation of urban resilience and climate actions in Honiara, Solomon Islands. Adaptation measures involve a combination of hard and soft actions; as well as activities designed to strengthen local capacity to respond to contemporary resilience challenges. Addressing the adaptive capacity component, this paper also highlights the opportunities for Australian universities to integrate teaching and learning with action research to achieve a substantive real-world impact in the Pacific region, as well as illustrating the capacity strengthening benefits that can be achieved through sustained engagement and collaborative partnerships with local organisations.

Frequent cases of gastroenteritis, resulting in several fatalities within remote communities in the Yasawa Islands, Fiji, prompted an urgent drinking water quality and supply assessment. This project initially investigated the quality of drinking water from multiple sources in communities on Naviti Island. Escherichia coli was detected in all sampled sources, including wells, springs, and rainwater tanks (above ground). E. coli most probable number counts were higher in well and spring water (typically >100 organisms per 100 mL) than rain tanks (ranging between 13.6 and >100). Assessment of potential water treatment alternatives, incorporating community input, determined that disinfection of rain tanks through chlorination was the most feasible and community acceptable option to address the contamination. A model was then developed to assess: (1) the likelihood that a typical household rainwater tank could adequately supply water throughout the wet and dry seasons and (2) the likely free chlorine residual that would result from a program of periodic dosing with 12.5% sodium hypochlorite. In a pilot trial in Mua-Ira village, chlorination of rainwater tanks proved successful in removing E. coli and community rollout was initiated. Periodic chlorination paired with tank and gutter maintenance were recommended to community and a local partner organization, and a training package was developed to assist this. The project holds potential to minimize pathogenic bacterial contamination in the studied drinking water sources and serve as a model to address water contamination through simple, low-cost, community-accepted solutions in the wider region.

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