Thesis (MEng)--Stellenbosch University, 2013. / Please see accompanying Errata document to be viewed with original document. / ENGLISH ABSTRACT: The current housing backlog facing the informal residents of South Africa is daunting. With current research showing that the backlog is not shrinking fast enough, the stakeholders of the formal and informal housing sector are facing an immense challenge. Most houses constructed after 1994 utilised conventional brick and mortar construction, with alternative means of building homes taking up a negligible share in the total housing supply. The purpose of this study is to test the feasibility of container-based homes as an alternative to brick and mortar homes in South Africa’s low-cost housing supply according to the triple constraints of project management i.e. cost, time and quality. Social acceptance and environmental sustainability are also analysed as two secondary parameters that will influence container-based projects. These parameters form the basis of the three pillars of sustainability, i.e. economic, societal and environmental parameters, which indicates the feasibility of a new design implementation. Two test cases for the feasibility study were designed. The first case considers a modular single-storey residential home, equivalent to standard “Breaking New Ground” housing solutions. The second test case considers a multi-storey, medium-density residential building, capable of housing multiple families .The test cases represent possible container-based solutions, with traditional brick and mortar construction (single and multi-storey) acting as the control solution. The three sustainability parameters act as benchmarks of each solutions’ feasibility, with the control solution acting as the counter-performance example. The comparison of the economic parameter relies on the cost of each design case, its construction time and the quality of the end-product. The bills of quantities were measured against a conventional building type, and it was found that a single-storey solution will prove more costly than a small brick and mortar home. However, the multi-storey solution proves to be feasible when compared to a concrete three-storey structure. Regarding time, the construction of an Intermodal Steel Building Unit (ISBU) home is up to 3 times faster compared to a conventional house. The end-product quality will depend on the quality system used by the contractor and its correct implementation; thus it is not an important dividing factor when comparing conventional versus Alternative Building Technology (ABT) systems. The societal parameter of an ISBU solution rests on its acceptance by the beneficiaries. Traditionally, resistance has met ABT home implementation, as stakeholders consider them as inferior products. A comprehensive survey was carried out in an informal settlement to test this statement. The results show that the majority of beneficiaries prefer conventional homes, unless the ABT home resembles its conventional counterpart. The environmental sustainability of a new product relies primarily on the carbon footprint of the materials and methods used. This was tested by comparing the impact of an ISBU solution with a conventional solution. The “upcycling” (as opposed to recycling) of used containers provides a large environmental benefit when comparing it to newly constructed brick for conventional homes, and thus the impact is lower. The findings of the study show that a single-storey solution utilising containers proves ineffective, as it is more expensive per square meter than a conventional home. However, a multi-storey container solution is feasible, as it is lower in cost (than comparative conventional solutions), faster to construct, allows for higher density expansion of settlements and is more environmentally friendly. / AFRIKAANSE OPSOMMING: Die enorme behuisingsagterstand van informele nedersetters in Suid-Afrika skep 'n geweldige uitdaging vir die rolspelers in die formele behuisingsektor. Huidige navorsing toon dat hierdie agterstand nie vinnig genoeg verminder nie, en baie mense verkeer in nood. Die meerderheid van huise wat opgerig is sedert 1994 maak gebruik van konvensionele baksteen en sement konstruksie, terwyl alternatiewe maniere van konstruksie 'n nietige aandeel het. Die doel van hierdie studie is om die bruikbaarheid van skeepshouer-gebaseerde huise te bepaal in teenstelling met konvensionele baksteen en sement huise, spesifiek vir die lae-koste behuisingsgeval in Suid-Afrika. Dit word uitgevoer volgens die "drietallige beperking" beginsel van projekbestuur, naamlik koste, tyd en kwaliteit parameters. Addisioneel word die sosiale aanvaarbaarheid sowel as die omgewingsvriendelikheid van die konsep getoets teen konvensionele maniere van konstruksie. Hierdie parameters vorm saam die “drie pilare van volhoubaarheid”, wat betrekking het tot ekonomiese-, sosiale- en omgewings-aspekte. Twee toetsgevalle is ontwerp volgens argitektoniese en tegniese standaarde sowel as gemeenskap benodigdhede. Die eerste geval is ontwerp as 'n enkel-verdieping huis, met behulp van modulêre skeepshouers. Die tweede geval is 'n meertallige-verdieping, medium-digtheid residensiële gebou wat verskeie families kan huisves. Die toetsgevalle modelleer verskeie skeepshouer oplossings, terwyl konvensionele konstruksie oplossings dien as beheer gevalle. Elke geval word volgens die drie volhoubaarheids beginsels getoets, met die beheer gevalle wat dien as die teen-prestasie voorbeelde. Die vergelyking van die ekonomiese parameter berus op die koste van elke ontwerp, sy konstruksietyd en die eindproduk kwaliteit. Die lys van hoeveelhede is gemeet teen dié van ʼn konvensionele huis, en daar is bevind dat die enkelverdieping skeepshouer-geval veel duurder sal wees. Die meertallige-verdieping geval aan die ander kant, maak gebruik van baie kostebesparings metodes, en lyk uitvoerbaar. Die tyd-aspek wys dat die konstruksie m.b.v. “Intermodal Steel Building Units” (ISBUs) tot en met 3 keer vinniger te wees teenoor ʼn konvensionele huis. Die eindproduk kwaliteit hang af van die tipe kwaliteit stelsel wat die kontrakteur gebruik, sowel as die korrekte toepassing van hierdie stelsel; dus is dit nie ʼn skeidende faktor tussen alternatiewe en konvensionele boumetodes nie. Die gemeenskaplike aspek van die gebruik van alternatiewe konstruksie berus op die aanvaarding van die huisbewoners. Gemeenskappe het tradisioneel nie ʼn hoë dunk van Alternatiewe Bou-Tegnologie (ABT) behuising nie, aangesien hulle dit as swak kwaliteit bestempel. Om hierdie stelling te toets is ʼn opname uitgevoer in ʼn informele nedersetting. Die resultate wys dat die meerderheid inwoners die konvensionele opsie verkies. Daar is wel bevind dat die inwoners ʼn ISBU huis sal oorweeg indien dit ʼn visuele ooreenkoms toon met ʼn konvensionele huis. Die omgewingsvolhoubaarheid van ʼn nuwe produk berus hoofsaaklik op die koolstof-voetspoor van die materiale en boumetodes wat gebruik is. Hierdie aspek is getoets deur ʼn ISBU oplossing se omgewings-impak te meet teen dié van ʼn konvensionele huis. Die “upcycling” voordeel wat skeepshouers gebruik gee ʼn groot voordeel teenoor die konstruksie van konvensionele huise, siende dat min nuwe materiale gebruik word. Dus is die totale omgewings impak laer as die van ʼn konvensionele huis. Die bevindinge van die navorsing wys dat ʼn enkelverdieping ISBU oplossing onprakties is in terme van koste per vierkante meter, aangesien dit veel duurder as ʼn konvensionele metode is. Die meertallige-verdieping geval is wel uitvoerbaar, aangesien dit ʼn laer koste tot gevolg het, vinniger gebou word, hoër-digtheid behuising bevorder en meer omgewings-vriendelik is.

Le logement est l’un des besoins fondamentaux de l’homme, comme la nourriture et le vêtement. Or, les régions métropolitaines de Jakarta et de Surabaya font face à une crise du logement. La pénurie de logements a atteint 1, 02 million dans le « Grand Jakarta » et 46 058 dans le « Grand Surabaya » en 2015. Cette étude décrit le déséquilibre entre la demande et l’offre de logements dans ces deux régions métropolitaines, et les efforts des différents acteurs (publics et privés) à trois époques différentes : « l’Ordre Ancien », « l’Ordre Nouveau », et « la Réforme/ Démocratie décentralisée » pour résoudre ce problème. Cette étude cherche en outre à lister les difficultés rencontrées par tous les acteurs dans la construction de logements décents et abordables depuis l’ère de « la démocratie décentralisée ». Enfin, cette étude examine la stratégie de coopération multi-acteurs qui a été adoptée pour réduire la pénurie de logements depuis « la Réforme ». Cette stratégie semble prometteuse car les acteurs partagent leurs rôles de sorte que la mise en œuvre des projets de construction de logements bon marché devient plus réalisable, notamment dans les grandes régions urbaines. / Housing is one of the basic needs, like food and clothing. However, the metropolitan areas of Jakarta (Jabodetabek) and Surabaya (Gerbangkertosusila) are dealing with a huge housing shortage. In 2015, the number of housing needs has reached 1, 02 million in the "Greater Jakarta" and 46.058 in the "Greater Surabaya". Due to this issue, the study firstly describes the imbalance between supply and demand of low-cost housing in these two metropolitan areas, and then the attempts of the various actors involved (public and private) to solve this problem since the nation’s independence era until the presents days (“Old Order”, “New Order”, and the “Reform/ Democratic decentralisation”). Secondly, this study explores different factors that interfere the supply of affordable housing during the era of "democratic decentralisation”. Finally, this study examines several multi-actors cooperation strategies that were adopted lately to reduce the housing shortage. These strategies seem promising because each actor are capable of sharing their roles so that the implementation of low-cost housing development projects can become more feasible, especially if they will be implemented in the large urban areas.

ABSTRACT The purpose of the study is to evaluate the housing process of Witzenberg Local Municipality and determine the involvement of the community and their perception regarding the whole process. The researcher is using a qualitative method to obtain the views, perspectives and feelings of the participants. For the purpose of the study is data collection limited to the sample population of people on the waiting list and those already in possession of low-cost house of the seven townships in the Witzenberg Local Municipality to. The researcher made use of questionnaires and interviews to collect data to make a profound finding and recommendation. In Witzenberg, 41% of households earn less than R30000 per annum (Witzenberg Local Municipality 2012: Online) which indicate that the Witzenberg Local Municipality has a high need for subsidized housing. The waiting list for low-cost housing in the Witzenberg Local Municipality currently stands at 6278 of which 1478 are a blocked housing project and a backlog of 4800 houses. The inhabitants of the Municipality received low-cost housing 8 years ago (Witzenberg Local Municipality 2012: Online). Witzenberg Local Municipality does has a housing problem, which stems from finance, affordability, insufficient land to erect housing projects, overcrowding, and quality of housing, staff shortage, unemployment, uncontrolled farm evictions and community involvement (Witzenberg Local Municipality 2007a:Online). Low-cost housing is in demand to address the challenges. Farm evictions, influx into the Witzenberg Local Municipality and forming of informal dwellings and increasing of squatter camps hold a serious threat to build sustainable, quality low-cost housing in the Witzenberg Local Municipality and with limit staff is in-flux control very hard to manage. Although the homeowners of the Witzenberg Local Municipality are happy to have received houses, they expressed much concern about the poor construction work, overall quality of the materials used as well as the housing process adopted by the Witzenberg Local Municipality. / Public Administration / M. Admin.

[ES] El descubrimiento del cemento Portland ha cambiado nuestra forma de construir, pero también es el responsable de grandes emisiones de CO2 a la atmósfera durante su fabricación (~1450 ᴼC), agravando la crisis actual que está sufriendo nuestro planeta debido al cambio climático y sus consecuencias en todo el medio ambiente. Por lo tanto, una alternativa más sostenible en la construcción es la utilización de la cal que necesita menor temperatura para su fabricación (~900 ᴼC). Si bien la introducción de puzolanas naturales o artificiales en morteros de cal han mejorado sus propiedades mecánicas y de durabilidad, estas aún tienen el inconveniente de ganar resistencias a edades largas de curado. Es por esta razón que en la presente tesis se pretende eliminar este inconveniente técnico, buscando la asociación de la cal con nuevos conglomerantes más sostenibles a partir de residuos para obtener morteros mixtos denominados cal/puzolana-geopolímero. Los residuos estudiados fueron: el catalizador gastado de craqueo catalítico, la ceniza de cascara de arroz, la tierra diatomea de origen residual y la ceniza de lodo de depuradora. También se estudia una puzolana natural proveniente de la República de Guatemala. En los morteros cal/puzolana (cal/FCC, cal/CCA, cal/CLD) se ha realizado sustituciones en peso hasta un 50 % de la mezcla cal/puzolana por geopolímero. El geopolímero se obtiene por una combinación del FCC como precursor y diferentes activadores alcalinos siendo estos la mezcla de: NaOH/Na2SiO3, NaOH/CCA, NaOH/TDN y NaOH/TDR. Los últimos tres sustituyen al silicato comercial como fuente de sílice alternativa. Asimismo, se realizaron estudios a nivel mecánico y microestructural. Para los estudios microestructurales, tanto de muestras endurecidas como de materiales de partida, se emplearon como técnicas: FRX, ADL, TG, DRX y FESEM. Los resultados han demostrado con éxito que añadir pequeñas cantidades de geopolímero sobre el sistema cal/puzolana fue notable, debido a que este potenció la formación de los nuevos productos de reacción, lo que mejoró la resistencia mecánica de los morteros desde las primeras horas de curado, llegando a obtener 7 veces más de resistencia que un mortero control cal/puzolana en 1 día de curado. El reemplazo del silicato de sodio comercial por CCA, TDN, TDR, como fuente de sílice, condujo a mejores desempeños del mortero en términos de resistencia a la compresión. Además, redujo el coeficiente de absorción de agua por capilaridad y aumento el tiempo de exposición a los ciclos hielo-deshielo frente a los morteros activados con activadores comerciales. Finalmente, los conglomerantes desarrollados en este estudio podría beneficiar tanto a la gestión de residuos como al desarrollo de materiales de construcción más sostenibles, aportando a los objetivos propuestos en la agenda 2030. / [CA] El descobriment del ciment Portland ha canviat la nostra manera de construir, però també és el responsable de grans emissions de CO¿ a l'atmosfera durant la seva fabricació (~1450 ᴼC), agreujant la crisi actual que està patint el nostre planeta degut al canvi climàtic i les seves conseqüències en tot el medi ambient. Per tant, una alternativa més sostenible en la construcció és la utilització de la calç que necessita menor temperatura per a la seva fabricació (~900 ᴼC). Si bé la introducció de putzolanes naturals o artificials en morters de calç han millorat les seves propietats mecàniques i de durabilitat, aquestes encara tenen l'inconvenient de guanyar resistències a edats llargues de curat. És per aquesta raó que en la present tesi es pretén eliminar aquest inconvenient tècnic, buscant l'associació de la calç amb nous conglomerants més sostenibles a partir de residus per a obtenir morters mixtos denominats calç/putzolana-geopolímer. Els residus estudiats van ser: el catalitzador gastat del craqueig catalític, la cendra de closca d'arròs, la terra diatomea d'origen residual i la cendra de llot de depuradora. També es va estudiar una putzolana natural provinent de la República de Guatemala. En els morters calç/putzolana (calç/FCC, calç/CCA, calç/CLD) s'ha realitzat substitucions en pes fins a un 50 % de la barreja calç/putzolana per geopolímer. El geopolímer s'obté per una combinació del FCC com a precursor i diferents activadors alcalins, sent aquests la mescla de: NaOH/Na2SiO3, NaOH/CCA, NaOH/TDN i NaOH/TDR. Els últims tres substitueixen al silicat comercial com a font de sílice alternativa. Així mateix, es van realitzar estudis a nivell mecànic i microestructural. Per als estudis microestructurals, tant de mostres endurides com de materia primera, es van emprar tècniques com: FRX, ADL, TG, DRX i FESEM. Els resultats han demostrat amb èxit que afegir petites quantitats de geopolímer sobre el sistema calç/putzolana va ser notable, pel fet que aquest va potenciar la formació dels nous productes de reacció, la qual cosa va millorar la resistència mecànica dels morters des de les primeres hores de curat, arribant a obtenir 7 vegades més de resistència que un morter control calç/putzolana en 1 dia de curat. El reemplaçament del silicat de sodi comercial per CCA, TDN, TDR, com a font de sílice, va conduir a millors acompliments del morter en termes de resistència a la compressió. A més, va reduir el coeficient d'absorció d'aigua per capil·laritat i va augmentar el temps d'exposició als cicles gel-desgel enfront dels morters activats amb activadors comercials. Finalment, els conglomerants desenvolupats en aquest estudi podrien beneficiar tant a la gestió de residus com al desenvolupament de materials de construcció més sostenibles, aportant als objectius proposats en l'Agenda 2030. / [EN] The discovery of Portland cement has changed the way we build; however, it is also responsible for large CO2 emissions into the atmosphere during its manufacturing (~ 1450 ᴼC), thereby aggravating the current crisis that our planet is suffering due to climate change and its consequences in the environment. Thus, a more sustainable alternative in construction is the use of lime that requires a lower temperature for its manufacturing (~ 900 ᴼC). The introduction of natural or artificial pozzolans in lime mortars has improved their mechanical properties and durability. Nevertheless, they present some technical disadvantages, as the low compressive strength, especially at early curing time. This thesis aims to eliminate this technical disadvantage by mixing lime with new more sustainable binders derived from waste, obtaining mixed mortars called lime/pozzolan-geopolymer The waste materials studied included fluid catalytic cracking residue (FCC), rice husk ash (CCA), residual diatomite (TDR) and sewage sludge ash (CLD). A natural pozzolan from the Republic of Guatemala was also studied. In the experimental procedure, in lime/pozzolan mortar mixtures (lime/FCC, lime/CCA, lime/CLD), up to 50% of their weight was substituted by geopolymer. The geopolymer is obtained by combining FCC as a precursor, and different alkaline activator mixtures including NaOH/Na2SiO3 (commercial waterglass), NaOH/CCA, NaOH/TDN, and NaOH/TDR, with the last three being an alternative silica source to commercial waterglass. In the same way, both mechanical and microstructural studies were carried out. The following techniques were used: XRF, ADL, TG, XRD and FESEM to assess the microstructural properties of both the raw materials and the hardened samples. The results have demonstrated that adding small amounts of geopolymer to the lime/pozzolan system was remarkable; it enhanced the formation of new reaction products, which improved the mechanical strength of the mortar from the first hours of curing, obtaining 7 times more strength than the lime/pozzolan control mortar in 1 day of curing. The replacement of commercial waterglass by CCA, TDN, TDR, as a source of silica, led to better performance of the mortar in terms of compressive strength. In addition, the coefficient of water absorption by capillarity was reduced and the exposure time during freezing-thawing cycles was increased compared to mortars activated with commercial activators. Finally, the binders developed in this study could benefit both waste management and the development of more sustainable construction materials, contributing to the objectives proposed in the 2030 Agenda. / Gracias al programa ADSIDEO-COOPERACIÓN de la Universitat Politècnica de València, que me ha brindado financiación para la presente investigación. / Villca Pozo, AR. (2021). Utilización de geopolímero para la mejora de las propiedades en morteros cal-puzolana y su empleo en países en desarrollo [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/172663