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Flexural behaviour of unreinforced alternative masonry walls
Thesis (MEng)--Stellenbosch University, 2020.
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| Format: | Thesis |
| Language: | en_ZA |
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Stellenbosch : Stellenbosch University
2020
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| _version_ | 1867613901952122880 |
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| access_status_str | Open Access |
| author | Jooste, Jean-Pierre Daniel |
| author2 | De Villiers, Wibke Irmtraut |
| author_browse | De Villiers, Wibke Irmtraut Jooste, Jean-Pierre Daniel |
| author_facet | De Villiers, Wibke Irmtraut Jooste, Jean-Pierre Daniel |
| author_sort | Jooste, Jean-Pierre Daniel |
| collection | Thesis |
| dc_rights_str_mv | Stellenbosch University |
| description | Thesis (MEng)--Stellenbosch University, 2020. |
| format | Thesis |
| id | oai:scholar.sun.ac.za:10019.1/109392 |
| institution | Stellenbosch University (South Africa) |
| language | en_ZA |
| last_indexed | 2026-06-10T12:43:30.888Z |
| license_str | Other — see source repository |
| provenance_str_mv | Harvested via OAI-PMH from SUNScholar — Stellenbosch University Repository |
| publishDate | 2020 |
| publishDateRange | 2020 |
| publishDateSort | 2020 |
| publisher | Stellenbosch : Stellenbosch University |
| publisherStr | Stellenbosch : Stellenbosch University |
| record_format | dspace |
| source_str | SUNScholar — Stellenbosch University Repository |
| spelling | oai:scholar.sun.ac.za:10019.1/109392 Flexural behaviour of unreinforced alternative masonry walls Jooste, Jean-Pierre Daniel De Villiers, Wibke Irmtraut Stellenbosch University. Faculty of Engineering. Dept. of Civil Engineering. Squatter settlements Low-income housing -- South Africa Flexural strength Compressed-stabilised earth Thesis (MEng)--Stellenbosch University, 2020. ENGLISH ABSTRACT: Over two million households in South Africa reside in informal housing. In an e ort to provide adequate formal housing to these citizens, government subsidised 40m2 houses are being constructed, referred to collectively as low-income housing (LIH). The walling systems of these structures are predominantly unreinforced masonry (URM) constructed out of conventional masonry units (CMUs). In South Africa, red clay brick and concrete blocks are the CMUs of choice. The environmental performance of these materials is poor due to the high temperatures required to manufacture red clay brick and cement. Furthermore, the chemical reaction that produces cement clinker releases CO2 regardless of the source used to heat it. To reduce the environmental impact of providing LIH, it has been proposed that these structures could be built using alternative masonry units (AMUs) with lower embodied carbon values and improved thermal performance. The ongoing adoption of the performance-based European masonry building code (Eurocode 6) provides an avenue for AMUs to gain access into the local housing market. However, to facilitate the development of AMU-speci c performance based regulations, the minimum mechanical requirements of AMUs need to be determined. According to the South African loading code (SANS 10160 - Parts 1, 3 and 4) buildings must be able to withstand wind and, in certain areas, seismic loads. The walls of LIH must be able to withstand the out-of-plane (OOP) application of these loads through exure. This thesis is an experimental investigation into the exural behaviour of URM walls constructed out of AMUs. It forms part of an e ort by a research group at Stellenbosch University to determine the minimum mechanical requirements of a broad spectrum of AMUs. This spectrum is represented by units composed of geopolymer (GEO), compressed stabilised earth (CSE) and adobe (ADB). One CMU, composed of concrete (CON) acts as a benchmark across all of the studies. To determine the exural behaviour of walls constructed from these materials, a large quantity of the aforementioned units were manufactured in such a way as to closely match those produced by other members of the research group. Two cement-sand mortars with target strengths of 7MPa and 20MPa were developed for the construction of masonry specimens. Thereafter, a exural strength test setup was developed and used to conduct tests on small walls constructed out of these units and mortars. To supplement the exural wall strength results, the compressive strength and modulus of elasticity of the masonry, units and mortar was also tested. Further tests were also conducted on the unit dry density and on the mortar consistency and exural strength. The developed test setup successfully tested walls constructed out of 20MPa and 7MPa mortar for each unit-type investigated. The exural strengths of the CON, GEO and CSE walls were equivalent to or greater than design exural strengths proposed by local design standards for equivalent CMUs. This implies that these materials are strong enough to withstand relevant OOP loading in standard design con gurations. The data produced from this test and the supplementary tests are suitable for use in numerical modelling and contributes to the existing body of literature on AMUs. This further contributes to the cause of developing performancebased standards for AMUs. AFRIKAANSE OPSOMMING: Meer as twee miljoen huishoudings in Suid-Afrika maak gebruik van informele behuising. In 'n poging om voldoende formele behuising aan hierdie burgers te verskaf, word regeringsgesubsidieerde 40 m2 -huise gebou wat gesamentlik as lae-inkomstebehuising (LIH) bekendstaan. Die muursisteme van hierdie strukture is hoofsaaklik onbewapende messelwerk (URM) wat uit konvensionele messelwerkeenhede (CMU's) bestaan. In Suid-Afrika word gebrande kleibakstene en betonblokke die algemeenste as CMU's gekies. Die omgewingsimpak van hierdie materiale is hoog as gevolg van die hoë temperature wat vereis word om kleibakstene en sement te vervaardig. Verder stel die chemiese reaksie wat sementklinker produseer ook CO2 vry, ongeag die bron wat gebruik is om dit te verhit. Om die omgewingsimpak van LIH te verminder, is daar voorgestel dat hierdie strukture gebou kan word met behulp van alternatiewe messelwerkeenhede (AMU's) met laer koolstof inhoud en verbeterde termiese gedrag. Die voortdurende gebruik van die prestasiegebaseerde Europese messelwerkboukode (Eurocode 6) bied 'n weg vir AMU's om toegang tot die plaaslike huismark te kry. Om die ontwikkeling van AMU-spesi eke prestasiegebaseerde regulasies te vergemaklik, moet die minimum meganiese vereistes van AMU's egter bepaal word. Volgens die Suid-Afrikaanse laskode moet geboue wind en, in sekere gebiede, seimiese lasgevalle kan weerstaan. Die mure van LIH moet die uit-vlak (OOP) aanwending van hierdie laste deur middel van buiging kan weerstaan. Hierdie tesis is 'n eksperimentele ondersoek na die buiggedrag van URM-mure wat uit AMU's bestaan. Dit vorm deel van 'n poging deur 'n navorsingsgroep aan die Universiteit Stellenbosch ten doel om die minimum meganiese vereistes van 'n wye spektrum AMU's te bepaal. Hierdie spektrum word voorgestel deur eenhede wat uit geopolymer (GEO), saamgeperste gestabiliseerde grond (CSE) en adobe (ADB) bestaan. Een CMU, saamgestel uit beton (CON), dien as die maatstaf vir al die studies/eksperimente. Om die buiggedrag van mure wat uit hierdie materiale bestaan te bepaal, is 'n groot hoeveelheid van die bogenoemde eenhede op so 'n manier vervaardig dat dit goed ooreenstem met dié wat deur ander lede van die navorsingsgroep vervaardig word. Twee sement-sandmortels met teikensterktes van 7MPa en 20MPa is ontwikkel vir die konstruksie van messelwerkmonsters. Daarna is 'n opstelling vir buigsterkte-toetsing ontwikkel en gebruik om toetse op klein mure uit te voer wat uit hierdie eenhede en mortels bestaan. Om die buigsterkte-resultate aan te vul, is die druksterkte en elastisiteitsmodulus van die messelwerk, eenhede en mortel getoets. Verdere toetse is ook uitgevoer op die droë digtheid van die eenheid en op die mortel se bestendigheid en buigsterkte. Die ontwikkelde toetsopstelling het mure wat uit 20M en 7M mortel gebou is, suksesvol getoets vir elke eenheidstipe wat ondersoek is. Die buigsterkte van die CON-, GEO- en CSE-mure was dieselfde of beter as die buigsterkte wat deur plaaslike ontwerpstandaarde vir ekwivalente CMU's voorgestel is. Dit impliseer dat hierdie materiale sterk genoeg is om relevante OOP-laste in standaard ontwerpkon gurasies te weerstaan. Die data van hierdie toets en die aanvullende toetse is geskik vir gebruik in numeriese modellering en dra by tot die bestaande literatuur oor AMU's. Dit dra ook verder by tot die ontwikkeling van prestasiegebaseerde standaarde vir AMU's. Masters 2020-11-30T18:42:36Z 2021-01-31T19:48:05Z 2020-11-30T18:42:36Z 2021-01-31T19:48:05Z 2020-12 Thesis http://hdl.handle.net/10019.1/109392 en_ZA Stellenbosch University 165 pages application/pdf Stellenbosch : Stellenbosch University |
| spellingShingle | Squatter settlements Low-income housing -- South Africa Flexural strength Compressed-stabilised earth Jooste, Jean-Pierre Daniel Flexural behaviour of unreinforced alternative masonry walls |
| title | Flexural behaviour of unreinforced alternative masonry walls |
| title_full | Flexural behaviour of unreinforced alternative masonry walls |
| title_fullStr | Flexural behaviour of unreinforced alternative masonry walls |
| title_full_unstemmed | Flexural behaviour of unreinforced alternative masonry walls |
| title_short | Flexural behaviour of unreinforced alternative masonry walls |
| title_sort | flexural behaviour of unreinforced alternative masonry walls |
| topic | Squatter settlements Low-income housing -- South Africa Flexural strength Compressed-stabilised earth |
| url | http://hdl.handle.net/10019.1/109392 |
| work_keys_str_mv | AT joostejeanpierredaniel flexuralbehaviourofunreinforcedalternativemasonrywalls |