In this thesis, I contribute to the emerging theoretical knowledge of and policy discourse on sustainable urban infrastructure, as a potential solution to the myriad of ecological and socioeconomic developmental challenges, for middle-income contexts of the global south. To understand this under-studied theme better, this dissertation uses three emblematic case studies of utility departments in the City of Cape Town (CCT) - an in-depth study of the Solid Waste Management Department and supporting studies of the Electricity Services Department, and the Water and Sanitation Department - to determine the prospects and relevance of sustainable infrastructure in such contexts. Through an analysis of urban networked infrastructure, I provide novel insight into the underpinning institutional dynamics that reproduce the service delivery model, and highlight how innovative activities that reflect the principles of sustainable urban infrastructure become embedded within institutional practice. Two conceptual frameworks, developed from the literature, have guided the empirical research and the analysis. The first is a heuristic device that enhances our understanding of sustainable urban infrastructure knowledge and discourse. The second offers a way to understand how it is institutionally mediated. Specifically, these conceptual frameworks are applied to the cases to reveal how the CCT's utility departments respond to an emergent crisis within a sector and how they pursue purposive interventions that reflect the sustainable urban infrastructure theory and discourse. The research was carried out over a period of two years and six months, during which I conducted semi-structured and informal interviews, and extensive document analysis.

The purpose of this research is to investigate the impact of the implementation of the Alexandra Renewal Programme (ARP) on the lives of residents in the Johannesburg township of Alexandra, in South Africa. The urban renewal project was a government initiative in collaboration with the private sector and community-based organisations. The project aimed to improve the physical, social and economic environments of Alexandra, a densely-populated township whose history includes political resistance, poverty, high levels of crime and unemployment, and yet is located adjacent to South Africa's successful commercial capital, Sandton. The impact of urban renewal programmes such as the ARP has not been evaluated along every dimension, nor recently with concerns raised about the pace of government efforts to drive the change required. Hence, the objective of this study was to assess the impact of the Alexandra urban renewal programme on its residents. Alexandra typifies the socio-economic marginalisation of black urban neighbourhoods during the apartheid era. Nearly 500 000 people live in approximately 100 000 households in formal and informal housing; unemployment is estimated at 60%, and most household incomes fall below the extreme poverty line of less than USD1 per person per day. Hence the ARP was designed to boost job creation, promote a healthier environment, through provision of affordable and sustainable services, such as decent housing, roads, water supply, sanitation and other infrastructure, and to reduce crime. The case study was conducted using qualitative research techniques. Focus groups were conducted with 32 residents from formal and informal settlements in the township. Research data was analysed using thematic content analysis. As a former resident of Alexandra with a long family history in the township, the researcher could provide a grounded and corroborative insight into the phenomenon under study. The research findings indicate that the implementation of the ARP programme has been generally consistent with the designed outcomes. The respondents indicated that the programme had some positive impact on improved access to government facilities and services, and on some housing and infrastructure projects. However, the participants also expressed frustration, and indicated that they had not gained significant benefits, especially on job creation and business opportunities. In addition, the residents believed that more could be done on the provision of basic services such as housing, water and sanitation. The effectiveness of government officials responsible for the ARP was also a concern. The study recommends that the three spheres of government (national, provincial and local) should collaborate more to develop relevant policies which drive urgency and effectiveness into the implementation of the urban renewal programme (URP) in Alexandra, and in the Gauteng province in general. The findings of this study contribute to the broader review of URPs in South Africa, and can assist government's developmental structures in evaluating the impact of these and future programmes.

DIGITAL BOUNDARIES explores the notion of how ICTs and mobile devices can influence the social programming, spatial conditions and construction of public architecture. This topic is derived from the study of Urban Informatics which looks at three key actors: people, place and technology. This can be seen in South Africa where many young individuals inhabit public buildings in the urban environment purely to be connected to wireless internet through their mobile devices. This is done so that they are able to do research for studies, look for job opportunities or socialise. This digital infrastructure then becomes an important aspect of the public realm, not only for personal benefit and need, but for attracting people to place. Situated in the Nyanga Junction precinct south of Gugulethu, the architectural proposition looks at adding digital infrastructure to this complex precinct in the informal area of Cape Town through three scales of architecture; small, medium and large. The small scale is that of Wi-Fi hotspots at street level embedded within the informal market at ten strategically located sites. The medium scale interventions are upgrades to four existing trade posts elevated above at first floor level. Lastly the large scale which is of catalytic and institutional architecture at two proposed sites, of which one is the main architectural focus of the design dissertation and explored further. The architectural programme provides spaces for: IT learning and skills development to help individuals seek employment, collaborative hubs for those developing new entrepreneurial ideas, and youth hubs for students to study and socialise. These three scales and their locality have been informed by social thresholds developed through the theory and technology studies that have been influential in the urban strategy of the design dissertation. It has created a framework for digital infrastructure to be implemented that will help enhance the public realm for a safer and more conducive urban environment.

Globally, concrete is the most used construction material. Its embodied energy is relatively low, yet due to the vast quantities that are produced annually, it has substantial greenhouse gas (GHG) emissions associated with it. Of the concrete constituents, the manufacture of clinker - the basis of all conventional cements - contributes the most significant emissions. Therefore, to reduce the emissions associated with concrete manufacture, there has been extensive research into how clinker content can be reduced without compromising desired concrete properties. Existing methods for clinker reduction have, however, only allowed clinker replacement to a limited extent. This research investigated the more efficient use of clinker to minimise clinker content required to achieve desired mechanical and durability properties of concrete. The optimisation of powder (materials < 125 µm) packing, using filler materials with varying fineness, was identified to potentially increase clinker efficiency. The optimisation undertaken was the maximisation of powder packing density but without adversely affecting workability. The investigation entailed the application of analytical particle packing density models as well as experimental investigation. Two particle packing models, the Compaction Interaction Packing Model (CIPM) and the Modified Andreasen and Andersen Curve (MAAC) were applied. Various methods for determining the packing density of powder combinations were investigated which informed the use of the mixing energy test to provide experimental packing density data for the modelling procedures. The CIPM was used to optimise the powder phases of concrete as it incorporated the effect of surface forces on powder packing and the MAAC was used to complete the optimisation of fine and coarse aggregate materials. It was necessary to calibrate the CIPM through the selection of various model constants, based on the minimisation of the average error associated with predicted packing density. Despite the incorporation of surface force effects, the CIPM did not predict the trend in packing density observed for various experimental powder combinations with consistent accuracy. Combinations of cement with limestone of high and low fineness (relative to cement) were most accurately predicted but combinations with limestones of similar fineness to cement were less accurate. It was therefore apparent that the model inadequately accounted for the effects of varying particle size and the corresponding influence of surface forces on these particles. However, for practicality, model constants which minimised overall error were used to determine powder combinations enabling maximum packing density for use in optimised concrete mix design. Concrete mixes were designed in 2 phases. Initially water content was fixed, and limestone content was successively increased to 40 vol. % (Phase 1). Despite the formation of mixtures according to maximum packing density, the results showed that optimisation of packing density with a fixed water content was insufficient to reduce clinker content without adversely affecting compressive strength. However, workability was maintained without excessive superplasticiser (SP) dosage and oxygen permeability, water sorptivity and accelerated drying shrinkage were either improved or not adversely affected. This was attributed to the ability of fine fillers to prevent interconnectivity of the pore structure and the decreased volume of gel hydration products leading to reduced drying shrinkage. Compressive strength was tested for a binary (cement/limestone) and ternary (cement /limestone/fly ash (FA)) binder blend for Phase 2 in conjunction with a substantially reduced water content. Workability was adversely affected and both mixes required high SP doses, however, the FA blend required a relatively lower dose. Compressive strength was again decreased relative to the reference mix but when comparing Phase 1 and 2 mixes with predicted strength for equivalent w/c ratios, compressive strength was relatively unchanged, inferring little benefit of packing optimisation. However, binder efficiency indices (‘bi’) (between 5.3 and 6.9 kg/m3 /MPa) were reduced relative to data from previous investigations with similar strength class (between 10 to 20 kg/m3 /MPa), inferring increased binder performance. Powder packing optimisation thereby has the potential to enable clinker reduction, particularly for lower strength grade concrete, without adversely affecting compressive strength. Furthermore, the relatively unaffected durability indicators portray the beneficial effects of powder packing optimisation on increasing the impenetrability of concrete microstructure and it potential use in applications where durability is of importance. These findings also pointed to further possible reductions in the binder efficiency index below 5 kg/m3 /MPa if water content is further reduced (to maintain low water: cement ratio) and reactive SCMs are incorporated. However, further investigation and understanding of the fundamentals of powder packing is necessary to achieve a fully predictive process of low-clinker concrete mix design that can be universally applicable.

South Africa is undergoing a sustainability transition (ST) in its energy sector as part of its broader move towards a lowcarbon future. Past studies of the nascent ST using a multi-level approach have already proven obsolete after strong resistance from the incumbent energy regime almost derailed the fledgling renewable energy (RE) industry. After initially going to ground and contracting, the industry re-emerged strongly in South Africa’s cities, mostly in the form of rooftop solar photovoltaic (PV) systems. This study applies an integrated approach utilizing the Multi-level Perspective (MLP) to trace the current ST trajectory, whilst employing the Technology Innovation Systems (TIS) framework as a focal lens, recently adapted to the follower country context, to empirically investigate system development in the solar PV TIS. A survey was conducted to assess the drivers and challenges facing consumers of solar PV technology in cities, the results indicating that the rapid growth in distributed embedded generation (EG) was sparked by recent tax incentives and not the introduction of Feed-in Tariffs (FIT) offered by city municipalities. Whilst the RE sector and solar PV market have grown through consumer demand for EG, they still face resistance from the existing energy regime, needing further development in policy and regulation in order for South Africa’s ST to support a more complex web of distributed and embedded generation, mostly underpinned by RE technologies.

This research stems from reports of the interaction between the growing informal communities such as Makoko, the coastal plains of the degenerating Lagos contexts and their limited access to central infrastructure. The effects of climate change on the low-lying coastal plains further exacerbate the degeneration experienced in these contexts. Therefore this research examines how people live independently of central infrastructure in informal contexts such as Makoko and whether this autonomy can be embedded into interventions that are integrated within the socio-economic networks of these contexts in a bid to shift from defective central infrastructures to social infrastructures that transform the blighted Lagos contexts in a manner that builds resilience at a local level. By using Makoko as a site for exploration and communicating with the locals of the context, Lagos professionals and non-governmental organizations, it emerged that there is currently an unhealthy relationship between the state, its local governments and its informal communities such as Makoko, in that the city of Lagos is managed principally from the office of the governor. This central management results in infrastructures that are implemented without critical acknowledgement of the problems faced by individuals who live in the many informal contexts of Lagos thereby resulting in little or no observable transformation in its (Lagos) degenerating contexts. It was also observed that Makoko has a unique urbanity of soft infrastructures that lend themselves to different scales of functions in the context and diverge from the typical hard infrastructures employed by the Lagos state government. The observations and findings point to the fact that the relationship between the state and its people must be strengthened for delivered infrastructures to be of any consequence in realizing any positive social change and transform Lagos and settlements like Makoko from their states of human and environmental degeneration by acknowledging that these contexts have unique problems and urbanisms that must be fused into any interventions within their precincts in a sustainable, ecological and economical way. This move will go a long way in transforming and legitimizing Lagos's degenerating contexts as important facets of the city.

I den här rapporten kommer jag undersöka ifall den nya vägen 818 mellan Kilvo och Mukkavaara byggts enligt Trafikverkets standard gällande avvattning. Att inte säkerställa en god avvattning av vägen och på så sätt riskera att få vatten i vägkroppen kan vara helt avgörande för vägens livslängd. I de här arbetet så har jag sammanställt information om vägen och den tekniska beskrivningen som Trafikverket har skrivit och ifall Tyréns ritningar följer deras dokument. Enligt de kontrollberäkningar jag har gjort och kontrollerat dokumenten så följer alla diken och trummor de givna dimensioner som Trafikverket har satt och säkerställer att vägen ska klara den dimensionerade livslängden.

In Namibia, the design and construction specification of concrete (for durability) follows the traditional method of prescribing parameters which over time are believed to produce durable concrete. These parameters include concrete exposure definition, cover, concrete strength, concreting materials and concreting methods. International research has shown that some of these parameters do not have a direct relationship with the durability of “As-built” concrete structures; rather that concrete structures can be designed and constructed to meet specific performance levels of the environment they are built in. In this case, testing of the concrete during design, construction and post-construction (to set acceptable limits and confirm adherence to the limits) becomes part of the process. This project was undertaken to look at how concrete practices (design and construction specification) followed in Namibia have impacted on the durability of concrete structures. To achieve the objective, the approach followed included; first assessing the prevailing concrete conditions (in different areas across Namibia), reviewing current concrete design and construction specifications used in the industry and finally assessing practitioner knowledge on performance-based concrete design and construction specification. Concrete infrastructure in four towns (Walvis Bay, Swakopmund, Arandis and Usakos) were inspected and deteriorations recorded. From these inspections, an evaluation of the causes of the deterioration was undertaken. A comparison was undertaken on the prevalence of different deterioration mechanisms in the four areas. Design standards, for durability, followed by structural engineers in Namibia were reviewed including specifications demanded by different infrastructure developing agencies. The limitations of these were highlighted. Interviews and observations were undertaken with structural engineering practitioners on knowledge of design for concrete durability. From the information collected, the comparison and assessment it was concluded that there is a need to revise the concrete design and construction specification to ensure concrete performs better against the most significant risk to concrete service life; damage due to reinforcement corrosion. Concrete specifications need to have measurable durability parameters which can be used for acceptance of concrete works besides compressive strength. The Namibia Port Authority (NAMPORT) has taken a step in this direction with the development of concrete construction specifications which have adopted the South African Durability Index method as part of the concrete acceptance criteria. Challenges encountered (by NAMPORT) include lack of testing equipment and a lack of knowledge by material testing engineers. With Namibia having the challenge of not having a national concrete construction standard, it is further recommended that major infrastructure developers (Namibia Water Authority, NAMWATER, and Roads Authority, RA) should lead in adoption of similar specifications to the NAMPORT ones. As most engineers in Namibia undertake works for either NAMWATER or RA, the industry will be more willing to undertake the training of engineers on the South African durability index method as it will make economic sense. The training is recommended to include training of laboratories offering material testing services in Namibia.

Public participation has the potential to either enhance urban development outcomes or entrench disagreement and frustration. A major challenge for policy-makers is how to understand and then respond to the narratives, metaphors and arguments contributed by stakeholders. In analysing the public participation process for the Two Rivers Urban Park (TRUP) in Cape Town, this research applies argumentative discourse analysis to capture and analyse multiple dimensions of stakeholder contributions. Arguments, and other linguistic features, were linked to themes distilled from the data. Associating and matching these themes to stakeholder groups identified discourse coalitions. The analysis supports the claim that the development of TRUP involves more than merely a technical discussion. The metaphors, stories and arguments used by participants to discuss the development of TRUP refer to it as an emblematic issue for the development of the city, its history, the history of South Africa and globalisation across the world. The discourse coalitions identified illuminate diverging ideas of how cities ought to respond to the environment, the private sector and residents. Without this knowledge government cannot hope to respond to stakeholders in a manner they will find satisfactory.

Since 1994 the post-apartheid South African Government has recognized the importance of housing in improving the quality of life of its citizens. Following 10 years of a housing delivery model that saw the provision of nearly 1.6 million houses, the National Government introduced a new policy that sought to shift away from an emphasis on housing and rather a holistic focus on the quality of the settlement established. This new policy, Breaking New Ground (BNG) promoted the establishment of well-managed, liveable and equitable settlements incorporating social and economic infrastructure. The quality of the urban environment and the quality of public spaces within urban developments has been identified as contributing towards improving quality of life within these settlements. In mixedincome, integrated settlements - like those BNG claims to produce - the importance of public space is further emphasised because it compensates for limited space of the private home. However, these spaces are often considered as "nice-to-haves" and neglected in favour of basic services or housing. Despite the importance of public space and its contribution to the creation of sustainable human settlements, these spaces, although planned for in the initial phases of a development, still remain largely undeveloped. This research therefore questions whether public spaces within integrated housing developments are being used as intended. It also questions to what extent the necessity for increased urban densification has affected the provision of public space in integrated housing developments. This research attempts to answer the question from the perspective of professionals involved in the planning and implementation of integrated housing developments and not from the perspective of residents. A qualitative research approach has been adopted. Three settlements each representing an integrated housing development implemented in line with BNG principles and incorporating public spaces were selected as case studies and in-depth interviews with professionals involved in the planning and implementation of these developments were conducted. The research found that while public spaces are considered as beneficial and are included in the planning stages of a development, in reality the lived experience often differs. While the objectives of housing policies are to create sustainable human settlements, professionals still struggle to translate these objectives into practical guidelines and standards. Finally, it was observed that while public spaces do play a role in the shift from housing to human settlements, the process is one that occurs incrementally and over a period of time.