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The principles of structural reliability are firmly established to provide the basis for structural performance as incorporated in design standards. Reliability-based procedures provide for variabilities and uncertainties that could reasonably be expected during the design service life of the structure. However, not all possible conditions to which all structures are exposed during such an extended service period can be accounted for effectively and economically at the design stage. The assessment of the reliability performance of an existing structure therefore forms an integral part of structural management and engineering practice. Despite the lag between the development and implementation of a basis for design and assessment of structures, the extensive body of information on structural assessment progresses steadily towards standardisation. This paper provides a review of the progress to provide background information towards extending the scope of South African structural standards to include guidance on structural assessment. The focus is on such developments to include provisions for existing structures in Eurocode, together with related investigations. In addition to a general review of background investigations, interrelationships between the basis of design and assessment for Eurocode (potentially also for South Africa) are considered. The main elements of a standardised basis for assessment are defined, and alternative assessment approaches are presented and demonstrated by representative examples. In conclusion, an outline of a possible development path for implementation in South Africa is provided. [ABSTRACT FROM AUTHOR]

Recent advances in cloud-based technology has led to the rapid increase of geospatial web-based applications. The combination of GIS and cloud-based solutions is revolutionizing product development in the geospatial industry and is facilitating accessibility to a wider range of users, planners and decision makers. Accessible through an internet browser, web applications are an effective and convenient method to disseminate information in multiple formats, and they provide an interface offering interactive access to geospatial data, real-time integration and data processing, and application specific analysis tools. An example of such a web application is GeoTerraImage's monthly crop monitoring tool called GeoFarmer. This tool uses climatic data and satellite imagery processed through a complex rule-based algorithms to determine monthly climatic averages and anomalies, and most importantly the field specific crop status (i.e. is the field fallow, or is the crop emerging, or if the field has been harvested). Monthly field verification has formed a part of calibrating the growth classification outputs to further improve the accuracy of its monthly agricultural reporting. The goal of this application is to provide timely data to decision makers to assist them in field-level and regional crop growth monitoring, crop production and management, financial risk assessment and insurance, and food security applications. This web application has the unique advantage of being highly transportable to other regions, since it has been designed so it can easily be adapted to other seasonal growth response patterns, and up-scaled to regional or national coverages for operational use. [ABSTRACT FROM AUTHOR]

The genesis and potential industrial applications of Lwamondo and Zebediela Kaolins in South Africa were determined. Selected physico-chemical characteristics were determined. Mineralogical characteristics were determined using XRD and SEM; and geochemical characteristics were determined using XRF and LA-ICP-MS. Kaolin colours were generally light (Lwamondo) and brown (Zebediela). Both kaolins had low pH (<6.5) and EC (<50 µS/cm). The texture of Lwamondo Kaolin was generally loam and clay loam, whereas that of Zebediela was clayey, silty and loamy. Major mineral phases were kaolinite, smectite and plagioclase in Lwamondo Kaolin, and kaolinite in Zebediela Kaolin. The morphology of the kaolins consisted mainly of stacks of kaolinite flakes. The most dominant major oxides were SiO2, Al2O3 and Fe2O3, and the kaolins were slightly depleted in light rare earth elements. The studied characteristics indicated that the kaolins (i) formed in a supergene environment and (ii) are suitable for hollow bricks. [ABSTRACT FROM AUTHOR]