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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

The impact of the current public sector procurement system on the consulting engineering industry

Moos, Moegamat Fatgie January 2018 (has links)
The development of infrastructure in our country is seen as key to eliminating poverty and reducing inequality. This is confirmed by the establishment of the Presidential Infrastructure Coordinating Council who will coordinate the implementation of the 18 Strategic Infrastructure Projects as part of government's programme. For this infrastructure development programme to be successful, competent engineering professionals are needed. The engineering industry is currently in crisis due mainly to the effect the current public sector procurement system has had on it. The procuring of consulting engineering services is currently done primarily by competitive tendering where price is the deciding factor in the award of tenders. Tenders are evaluated solely on the basis of price and Broad Based Black Economic Empowerment requirements (also known as preference requirements). The criteria for expertise, experience and capacity are only used as qualifying criteria after which price and preference are used for the evaluation. This process is irrespective of the scale of the project or the skills required. The processes are governed by legislation such as the Public Finance Management Act, Preferential Procurement Policy Framework Act and the Municipal Finance Management Act. All public sector institutions and public entities are therefore governed by this and must ensure compliance. There has however been an acknowledgement on the part of government that the current system needs to be reviewed. National Treasury published the Public Sector Supply Chain Management Review in February 2015. This frank look at the current Supply Chain Management system highlighted the shortfalls and what is required to be done to improve the system. The important acknowledgement out of this review is that construction procurement is different to normal procurement and different systems should apply. Despite the initiatives launched by government the current procurement system for consulting engineering services remains unchanged and primarily price driven. Respondents in the private and public sectors were surveyed for their views on the current state of procurement. From the research it is clear that respondents both in the private and public sectors indicate that competition based on price should be changed. Due to low fees tendered consultants no longer have the luxury of seconding senior experienced staff to projects for extended periods of time. Training, development and mentoring of graduate staff has also become less and firms have limited ability to reinvest for growth. Public sector clients' perceptions also indicate that consultants' quality of service has deteriorated. In order to arrest the current situation the study recommends that clarity be sought on the relevant sections of the constitution dealing with procurement. Once this is achieved the National Treasury and the National Department of Trade and Industry should be engaged to get the applicable legislation amended to accommodate a quality and cost based selection system and that takes into account the scale and complexity of projects. This will lead to consultants getting paid fees commensurate with the effort required to execute projects thereby allowing consultants to reinvest in their businesses that will ensure its longevity. This will contribute positively to the infrastructure development required to eliminate poverty, reduce inequality and grow the economy.
102

Implementation of the DER rating system within a power generation environment

Gombele, Bokosa January 2018 (has links)
The main purpose of this research study is to test the applicability of the DER (Degree of defect, Extent and Relevancy of defect) rating system, used for road network infrastructures, to the support structures of a dry cooling tower in a power generation environment. The DER is a defect-based rating system developed locally by the Built Environment Division of the Council for Scientific and Industrial Research (CSIR) in Pretoria, South Africa. This study involved a visual inspection and the rating and analysis of defects of reinforced concrete (RC) structures in an Eskom power generation plant located in Grootvlei in Mpumalanga Province. Visual inspection and condition rating systems form part of an Asset Management System (AMS) that is used to ensure a safe operation and the economic benefit of the structure throughout its life cycle. For that reason, various organisations and roads authorities have developed condition-rating systems similar to the DER for visual assessment of their road network structures using a Bridge Management System (BMS) as a vehicle to achieve their operation and maintenance objectives. Other condition-rating systems have been identified and their applicability to structures in a power generation environment as compared to that of the DER was also tested. These condition-rating systems are: 1) The Overall Structural Condition Index (OSCI) - proposed by the Australasian Transport Research Forum (ATRF) for bridge condition assessment and prioritisation of maintenance activities and budget allocation. 2) The National Bridge Inspection Standard (NBIS) which establishes a uniform program for all state departments of transportation in the USA to regulate the minimum requirements for inspection types and procedures, inspection intervals, inspector qualifications, and inventory reporting, and 3) The Ontario Structure Inspection Manual (OSIM) which sets standards and provides uniform approaches for visual and detailed inspections and condition evaluation for all types of bridge structures in Ontario, Canada. Comparative rating analyses of the defects of the same RC structure in a power generation environment was conducted in order to establish the applicability of the DER in comparison with the other rating systems. The use of the DER, amongst other selected condition rating systems, was recommended with the suggestion that further improvement be undertaken so as to extend its usage within a power generation environment.
103

A critical review of the housing policy and the State's intervention in mining towns in South Africa

Manenzhe, Thiathu Darriyl 11 February 2019 (has links)
Since 2012, there has been increasing government interest in mining towns. This interest was occasioned by the Marikana shooting. This interest, led by the presidency through Inter-ministerial Committee on the Revitalisation of Distressed Mining Towns and Communities has had impact on human settlements. This dissertation provides an overview of the Mining Towns Programme and its evolution, identify some of the major pitfalls and assumptions of the programme, and propose an alternative. It also provides and reflects a sustained critique of the approach of the state in the creation of human settlements and the provision of housing in mining towns. Furthermore, the dissertation attempts to assess the efficacy of human settlements approach to mining towns. In doing this, I argue that despite the increased interest, the approach adopted has fundamental weaknesses. These weaknesses range from the fundamental departure from the original intention and focus of the programme, the over-reliance on the existing but inappropriate human settlements delivery instruments and the ignorance of and the weakened role of local government in the programme. In its reliance on the existing human settlements delivery instruments, the implementation and delivery of houses has not addressed the problems faced by mineworkers. Moreover, the state has also overlooked the deep historical challenges of mining towns, both in terms of context and practice and this has undermined the effective implementation of the programme. There are also other institutional and socioeconomic problems associated with mining towns and this has not been properly assessed. The dissertation critically evaluates the approach and the shortcomings of the Mining Towns Programme against these challenges and posits some alternatives.
104

Assessment of local water distribution infrastructure management and maintenance challenges

Mothetho, Motlatsi 01 February 2019 (has links)
Central to the South African government’s vision of providing services to all is on-going maintenance of public infrastructure. Since 1994 the government focused on addressing backlogs in the provision of water services through new infrastructure investment; however it failed to make sufficient investment in the maintenance and renewal of this infrastructure (SAICE, 2006). Older infrastructure is not being renewed or refurbished as required and planned preventative maintenance on new infrastructure is inadequate (SAICE, 2006). This has been generally attributed to poor management strategies that are exacerbated by lack of skills in water services utilities and low levels of funding provisions (Mescht & Jaarsveld, 2012; FFC, 2013). The continuing poor maintenance of water distribution networks has contributed to high leakage rates in South Africa (FFC, 2013; DBSA, 2012). To address challenges of maintenance of water distribution infrastructure a regulatory framework to guide municipalities is critical. The government approved the National Infrastructure Management Strategy (NIMS) in 2006 to support simultaneous infrastructure investment and maintenance (CIDB, 2008). One of the key thrusts of the strategy is the strengthening of the regulatory framework that governs planning and budgeting for maintenance. The literature survey of this study found that initiatives associated with the NIMS were very slow in gaining traction. The study reviews water services infrastructure management frameworks that are based on present legislative instruments and standards for two study areas; City of Capetown and City of Johannesburg. Challenges associated with effective management of water distribution infrastructure are assessed based on established infrastructure management policies, strategies and asset management plans for each entity. For each study area leakage control strategies are the key maintenance strategy outputs associated with the implementation of the management frameworks; therefore the study reviewed sector plans and annual reports to assess challenges associated with carrying out effective maintenance. The findings of the study show a correlation between the adoption of maintenance management strategies and the improvement of the performance of water distribution networks for both Cape Town and Johannesburg. The strategies are driven at the highest level of decision making in the municipalities as budgeting requirements are supported by the Integrated Development Plans of each study area. The maintenance allocations however remain below the international benchmark to enable the municipal entities to carry out satisfactory maintenance of their distribution infrastructure.
105

Housing for the poor: A case study of the Johannesburg inner city

Robb, Carla 19 February 2019 (has links)
This research focuses on the Johannesburg inner city, which is located in the Johannesburg Metropolitan Municipality, Gauteng Province, South Africa. Johannesburg inner city has had a tumultuous history, from being the most economically powerful urban centres in Sub-Saharan Africa in the early 1900s, to falling into a state of disrepair from the 1980s, the inner city is now home to more than 300 000 households. The public sector and private sector both play a critical role in the delivery of affordable accommodation opportunities in the Johannesburg inner city, but the lack of formal supply of housing for the urban poor, specifically the “poorest of the poor” is stark. It is with this knowledge that this dissertation explores the commitment, from both public and private sector, to delivering accommodation options for the poorest of the poor in the inner city. The Johannesburg inner city has seen increased involvement from the private sector in the delivery of housing since 1994. Significantly, housing delivered by the private sector is accessible to the households in the income group referred to as the gap market. The lowest income group is left to resort to the informal sector to seek shelter. The lack of adequate housing supply for this group has given rise to illegal occupation of buildings, often run by slumlords with appalling living conditions. The public sector has many plans and strategies in place with identified mechanisms to assist in increasing the delivery of accommodation for this income group. However, there is still a massive gap in the delivery. Many plans and strategies have been put in place with the intention of addressing the housing demand in the inner city. Although many of these policies and strategies, created by the government, were intended to increase the delivery of affordable rental accommodation, what is obvious is the lack of delivery. This dissertation, therefore, intends to determine why there has been no formal provision made for the lowest income group in the Johannesburg inner city and, if there are plans or mechanisms in place to rectify this, why they have not come to fruition. The City of Johannesburg Metropolitan Municipality has been criticised for not responding to the emergency accommodation cases seriously and creating realistic strategies to deal with the poorest income group or destitute. There is a lack of a programmatic approach to meet the housing demand, which is evident from the number of bad buildings in the Johannesburg inner city. Without a realistic strategy to assist this income bracket, a domino effect of failure seems to plague housing delivery in the inner city. A lack of opportunities for this income group gives rise to bad buildings, which in turn affects the livelihood of the people in the inner city, across all sectors.
106

A comparative study on the structural behavior of concrete arch dams subjected to swelling due to aggregate sllica reactions

Stehle, Hermann Theodor 31 January 2019 (has links)
South Africa is considered a water-scarce country and this fact alone stresses the absolute need to preserve its water resources. As time goes by, the ageing of dams in South Africa is becoming an increasingly important factor to consider from a dam safety perspective. When considering concrete dams, Alkali Aggregate Reactions (AAR) which is the collective term referring to the potential chemical reactions between the cement and the coarse aggregate in the concrete, are a major cause of ageing. AAR causes internal swelling of concrete leading to stresses that eventually manifest on a macroscopic level as inter alia cracks, deformation and opening of horizontal construction joints. Although the effect of AAR expansion on arch dams is complex, certain behavioural phenomena have been identified as typical indicators of swelling concrete. These are well covered by literature. This thesis aims to compare the structural behaviour of concrete arch dams in South Africa that are subjected to swelling due to AAR. Three arch dams, namely Hartebeeskuil Dam, Poortjieskloof Dam and Thabina Dam (all located in different climatic regions), were identified and their behavioural patterns were investigated by using visual techniques along with the interpretation of instrumentation results. The typical instrumentation results that were used for interpretation purposes included geodetic surveying results, crack width gauge results, in situ stress measurement results and trivec measurement results. Poortjieskloof Dam, the oldest of the three dams, showed permanent upstream displacement trends of both flanks, but the centre of the arch showed a downstream displacement trend. Both flanks show swelling towards the abutments and rising crest levels are evident throughout the length of the dam wall. The dam wall was cracked quite severely on the downstream face and the horizontal joints showed clear separation. The most recent displacement trends suggest that the rate of AAR is decreasing. Hartebeeskuil Dam, the second oldest of the three dams, showed permanent upstream displacement trends throughout the length of the dam wall. Both flanks show swelling towards the abutments and crest levels at both flanks show some settlement. The central section of the arch show rising crest levels. The results of in situ stress measurements carried out in 1999 showed that the downstream section of the arch is experiencing tensile stresses while the upstream section of the arch is mostly experiencing compressive stresses. The cracking patterns on both the upstream and downstream faces seem to agree with these findings. The results generally seem to suggest that the AAR mainly occurs on the upstream side of the arch and that the effective arch has become thinner due to the tension zone on the downstream side. The most recent displacement trends suggest that the rate of AAR is not showing any signs of decreasing. Thabina Dam, the youngest of the three dams, showed permanent upstream trends of the right flank while the central region and left flank of the arch showed downstream trends. The flanks have moved permanently towards each other and the crest levels have increased throughout the length of the arch section. The most recent trends show increasing rates of strain especially in the vertical (z) and tangential (y) directions. More recently the entire arch has started showing upstream displacement trends. These may indicate the onset of a swelling mechanism in the concrete, most likely AAR, but extensive testing is required to prove this.
107

Are we ready? : Swedish road operators readiness for automated vehicles

Larsson, Alva January 2021 (has links)
The European Union as well as Governments all around the world,including the Swedish Government, are putting a lot of time, money andeffort into facilitating the implementation of Automated Vehicles (AVs).The majority of these efforts tend to focus on either the technicalaspects, action plans or the legal scope. However, little attention isbeing drawn to the practical implications of these efforts. Hence, this thesis investigates the road operators’ willingness to act and their readiness in regards to data and information provision for AVs, as well as how the readiness can be improved. In particular, focus is geared towards the three largest road operators in Sweden: the city of Stockholm, the city of Gothenburg and the Swedish Transport Administration. The primary segments of data consists of information gathered through semi-structured in-depth interviews and benchmarking against international road operators. The results show a gap between the official visions of being at the forefront in automated mobility, and the actual practical implementations of these visions in the road operator organisation's. The author assigns this gap to a lack of incitements, decision-making,and monetary assets. Moreover, the findings suggest a correlationbetween the approach towards automated mobility within the organisationsand the actual level of readiness. This correlation is intensifiedduring the second data collection, when benchmarking international road operators against the Swedish. Further, the author underlines theimportance of managing this gap in order to achieve the strong coordination needed to reach the set up goals. The paper conclusively suggests, by comparing how road operators work with such matters in theNetherlands, Norway and Finland, how to overcome such obstacles.
108

Klimatkalkyl, en konceptstudie

Stark, Elsa January 2020 (has links)
Klimatkalkylmodellen används i infrastrukturprojekt för både väg- och järnväg och tillhandahålls av Trafikverket. Verktyget är online baserat och uppdateras en gång per år. Hur vida en klimatkalkyl ska genomföras eller inte i projekten förhandlas fram i avtalen som skrivs mellan Trafikverket och AFRY. Klimatkalkylen resulterar i en sammanställning av samtliga typåtgärder och byggdelar som används och deras utsläpp beräknat i koldioxidekvivalenter. Utöver detta summeras även den totala användningen av bland annat asfalt med bitumen och diesel. Den totala sammanställningen presenteras i både koldioxidekvivalenter och energiförbrukning som presenteras i gigajoule. Med hjälp av denna sammanställning önskas ett verktyg tas fram för att underlätta uträkningar i klimatprojekt för att minska klimatutsläppen. Verktyget ska underlätta för konsulterna i sitt arbete att ta fram exempelåtgärder för att minska utsläppen ifrån projektet. Rapporten tar upp den konceptstudie som gjorts och tar fram exempel på hur framtagandet hur ett sådant verktyg kan se ut och rekommenderar AFRY att fortsätta med arbetet att ta fram detta.
109

Laboratory Seismic Testing of Asphalt Concrete

Gudmarsson, Anders January 2012 (has links)
Nondestructive laboratory seismic testing to characterize the complex modulus and Poisson’s ratio of asphalt concrete is presented in this thesis. These material properties are directly related to pavement quality and the dynamic Young’s modulus is used in thickness design of pavements. Existing standard laboratory methods to measure the complex modulus are expensive, time consuming, not truly nondestructive and cannot be directly linked to nondestructive field measurements. This link is important to enable future quality control and quality assurance of pavements based on the dynamic modulus.Therefore, there is a need for a more detailed and accurate laboratory test method that is faster, more economic and can increase the understanding and knowledge of the behavior of asphalt concrete. Furthermore, it should be able to be linked to nondestructive field measurements for improved quality control and quality assurance of pavements. Seismic testing can be performed by using ultrasonic measurements, where the speed of sound propagating through a material with known dimensions is measured. Seismic testing can also be used to measure the resonance frequencies of an object. Due to any excitation, a solid resonates when the frequency of the applied force matches the natural frequencies of the object. In this thesis, resonance frequency measurements have been performed at several different temperatures by applying a load impulse to a specimen while measuring its dynamic response. The measured resonance frequencies and the measured frequency response functions have been used to evaluate the complex modulus and Poisson’s ratio of asphalt concrete specimens. Master curves describing the complex modulus as a function of temperature and loading frequency have been determined through these measurements.The proposed seismic method includes measurements that are significantly faster, easier to perform, less expensive and more repeatable than the conventional test methods. However, the material properties are characterized at a higher frequency range compared to the standard laboratory methods, and for lower strain levels (~10-7) compared to the strain levels caused by the traffic in the pavement materials. Importantly, the laboratory seismic test method can be linked together with nondestructive field measurements of pavements due to that the material is subjected to approximately the same loading frequency and strain level in both the field and laboratory measurements. This allows for a future nondestructive quality control and quality assurance of new and old pavement constructions. / <p>QC 20121120</p>
110

On investigation of stripping propensity of bituminous mixtures

Bagampadde, Umaru January 2004 (has links)
In this study, an experimental programme was designed toestablish a relationship between bituminous mixture constituentmaterial properties and their propensity to moisture induceddamage in form of stripping. Six bitumen types (3 from Ugandaand 3 from Sweden) with presumably varying characteristics wereevaluated basing on rheology and chemistry. Eleven aggregateswere used in this study. Seven were sourced from activequarries in Uganda and four were from Sweden. Bitumen rheology was established basing on penetration,softening point, viscosity, ductility and visco-elasticparameters obtained from dynamic mechanical analysis. Bitumenchemistry was studied using Fourier Transform InfraredSpectroscopy, Gel Permeation Chromatography (GPC) and ThinLayer Chromatography (TLC). Bituminous mixtures were reconstituted from the bitumen andaggregate combinations basing on the Swedish mix designprocedure ROAD 94 using dense graded mixtures with 16mm maximumaggregate size (AG16). Mixture sensitivity to moisture wasevaluated basing on Swedish FAS 446-98 specifications closelyrelated to the modified Lottman procedure. The investigation was done in two phases namely, (a) theeffect of aggregate properties on mixture moisture sensitivityand (b) the of cross effects of bitumen and aggregates onmixture moisture sensitivity. The results reveal chemical compositional differences inbitumens that would be considered similar basing on classicalrheological properties like penetration and viscosity. Resultsof dynamic mechanical analysis show that binders have similarvisco-elastic response around 0oC. This could be a potentialphenomenon to serve as a grading scheme for bitumen as is thecase with penetration and viscosity grading systems. The results from phase I of the study show that presence ofCa-feldspars and ferromagnesian minerals in aggregates largelyrelates to improved resistance of mixtures to moisture damage.In addition, mixtures from aggregates with high concentrationsof acid insolubles (SiO2 and Al2O3) are sensitive to moisturedamage. The results of phase II of this study show that the choiceof aggregate type is the dominant factor affecting moisturesensitivity of the resulting mixtures. Bitumen type seems notto be an important factor in determining moisture sensitivityof bituminous mixtures. Aggregates with Ca-feldspars andferromagnesian minerals seemed to be the most resistant tomoisture damage irrespective of the bitumen type. Assessment of moisture sensitivity basing on absolutestiffness values of water treated mixtures seems not to bereliable. Results from this study show that mixtures withsimilar wet resilient moduli had varying tensile strengthratios, hence varying moisture sensitivity tendencies. Modulusof resilience ratio (MRR) and tensile strength ratio (TSR)parameters show similar trends in comparing moisturesensitivity of different mixtures. However, MRR values aregenerally lower than TSR values for the same mixtures.

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