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Fire Dynamics in Informal Settlements

dc.contributor.advisorWalls, Richard Shaunen_ZA
dc.contributor.authorCicione, Antonioen_ZA
dc.contributor.otherStellenbosch University. Faculty of Engineering. Dept. of Civil Engineering.en_ZA
dc.date.accessioned2019-11-19T19:05:03Z
dc.date.accessioned2019-12-11T06:46:56Z
dc.date.available2019-11-19T19:05:03Z
dc.date.available2019-12-11T06:46:56Z
dc.date.issued2019-12
dc.identifier.urihttp://hdl.handle.net/10019.1/107092
dc.descriptionThesis (DEng)--Stellenbosch University, 2019.en_ZA
dc.description.abstractENGLISH ABSTRACT: In poor and densely populated countries, the rapid growth in population leads to an increase in landlessness. As a result, the number of people residing in informal settlements is increasing on a daily basis. It is estimated that there are currently one billion people living in informal settlements and this number is expected to increase in the coming years. Currently, informal settlements are being ravaged by large fires every day across the globe. Over the past decades, fire related disasters have decreased in the global north, while they have increased in the global south. Since the number of people that reside in informal settlements are expected to increase, it is a cause for serious concern to see how little is done in terms of fire safety in these communities. It is with this in mind that this dissertation focusses on developing an in-depth understanding of fire dynamics in informal settlements, with the hope that it can form the basis for future research and fire safety innovations. In this dissertation four full-scale fire experiments have been carried out: (a) a single steel sheeting clad experiment, (b) a single timber plank clad experiment, (c) a triple dwelling steel sheeting clad experiment and (d) a triple dwelling timber plank clad experiment. The single dwelling experiments are analysed using two numerical models (i.e. two-zone modelling and Fire Dynamic Simulation (FDS) modelling) to obtain an understanding of the enclosure fire dynamics and heat fluxes emitted from these dwellings. A comparison between the model and experimental results are shown. The effect of different cladding materials (i.e. timber versus steel cladding) on the enclosure fire dynamics and heat fluxes experienced is also presented, where it was found that timber dwellings are more prone to fire spread, with heat fluxes exceeding 200 kW/m2 at the openings. It was found that the FDS models captured the behaviour of the single dwelling experimental fires well, but that the material properties of the cardboard lining have a substantial effect on how the fire develops, as a result of how the fire spreads across the surface of the cardboard. This was also the most difficult aspect to capture with the numerical models. The FDS models’ predictive capabilities were further utilised to determine a preliminary critical separation distance, where it was found to be approximately 3 m between dwellings (i.e. the distance needed for fire spread between dwellings not to occur under wind free conditions). The dissertation continues by presenting the results of the multi-dwelling experiments, where the basic understandings and findings drawn from the single dwelling experiments were used to examine the effect of different cladding materials on fire spread between dwellings. The multi-dwelling experimental results concurred that the timber dwellings are more prone to fire spread. These results highlighted the dangers of these closely spaced dwellings. For the timber clad dwellings, the overall spread time (i.e. from the start of flashover in the first dwelling to the end of flashover in the last dwelling) was approximately 4 minutes. Simplified FDS models are developed to predict fire spread between multiple dwellings, with the hope that these models can be improved over time so that they can be used to study housing configurations and fire spread interventions.en_ZA
dc.description.abstractAFRIKAANSE OPSOMMING: In arm en digbevolkte lande, lei die vinnige groei in bevolking tot 'n toename in grondloosheid. As ‘n gevolg veroorsaak dit ‘n daaglikse toename in die aantal mense wat in informele nedersettings woon. Daar word beraam dat daar tans een biljoen mense in informele nedersettings woon en dit sal na verwagting in die komende jare toeneem. Tans word informele nedersettings op ‘n dagliks basis wêreldwyd deur groot brande verwoes. Gedurende die afgelope dekades het brandverwante rampe in die noordelike halfrond afgeneem, terwyl dit toegeneem het in die suidelike halfrond. Aangesien die aantal mense wat in informele nedersettings woon na verwagting gaan toeneem, is dit rede vir ernstige kommer om te sien hoe min daar gedoen word in terme van brandveiligheid in hierdie gemeenskappe. Dit is met die bogenoemde in gedagte dat hierdie tesis fokus op die ontwikkeling van 'n indiepte begrip van vuurdinamika in informele nedersettings met die hoop dat dit die basis kan vorm vir toekomstige navorsing en brandveiligheidsinnovasies. In hierdie tesis was vier volskaalse vuur eksperimente uitgevoer: (a) 'n enkelwoning staalplaat-geklede eksperiment, (b) 'n enkelwoning houtplank-geklede eksperiment, (c) 'n drie woning staalplaat-geklede eksperiment, en (d) 'n drie woning houtplank-geklede eksperiment. Die enkelwoning eksperimente word ontleed met behulp van twee numeriese modelle (namelik tweesone-modellering en Fire Dynamic Simulation (FDS) modellering) om ‘n beter begrip te kry van die kompartement-vuurdinamika en hittevloei wat uit hierdie huise uitgestraal word. 'n Vergelyking tussen die model en eksperimentele resultate word getoon. Die effek van verskillende bekledingsmateriale (d.w.s. hout-bekleding teenoor staal-bekleding) op die kompartement-vuurdinamika en hittevloei wat ervaar was word ook getoon, en daar was gevind dat houthuise meer geneig is tot brandverspreidings met ‘n hittevloei van meer as 200 kW/m2 by die openinge. Daar is bevind dat die FDS-modelle die gedrag van die enkele woonbrande goed nageboots het, maar dat die materiaal eienskappe van die karton 'n wesenlike effek het op hoe die vuur ontwikkel. Dit is as gevolg van hoe die vuur oor die oppervlak van die karton versprei en dit was ook die moeilikste aspek om na te boots met die numeriese modelle. Die FDS-modelle se voorspellende vermoëns was verder gebruik om 'n voorlopige kritiese skeidingsafstand te bepaal, waar dit gevind was dat daar ongeveer 3 m tussen woonhuise moet wees (d.w.s. die afstand wat nodig is om brandverspreiding tussen wonings te verhoed onder windstil omstandighede). Die tesis gaan voort deur die resultate van die meervoudige-woning eksperimente aan te bied, waar die basiese begrippe en bevindings wat uit die enkelwoning-eksperimente getrek was, gebruik word om die effek van verskillende bekledingsmateriale op brandverspreidings tussen huise te ondersoek. Die meervoudige-woning eksperimentele resultate het bevestig dat die houthuise meer geneig is tot brandverspreidings en hierdie resultate het die gevaar van hierdie naby gespasieerde wonings beklemtoon. Vir die houtkledewonings ekperiment was die algehele verspreidingstyd ongeveer 4 minute gewees. Vereenvoudigde FDS-modelle was ontwikkel om die verspreiding tussen meervoudige wonings te voorspel, met die hoop dat hierdie modelle oortyd verbeter kan word sodat dit gebruik kan word om behuisingskonfigurasies en brandverspreidingsintervensies te bestudeer.af_ZA
dc.format.extent133 pages : illustrationen_ZA
dc.language.isoen_ZAen_ZA
dc.publisherStellenbosch : Stellenbosch Universityen_ZA
dc.subjectFires and fire preventionen_ZA
dc.subjectUCTDen_ZA
dc.subjectInformal settlements (Squatter settlements) -- Firesen_ZA
dc.titleFire Dynamics in Informal Settlementsen_ZA
dc.typeThesisen_ZA
dc.description.versionDoctoralen_ZA
dc.rights.holderStellenbosch Universityen_ZA


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