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The state of the art of cob construction: A comprehensive review of the optimal mixtures and testing methods

Haddad, Kamal, Latif, Eshrar ORCID: and Lannon, Simon ORCID: 2023. The state of the art of cob construction: A comprehensive review of the optimal mixtures and testing methods. Presented at: International Conference of Bio Based Buildings Materials (ICBBM 2023), Vienna, Austria, 21-23 June 2023. Bio-Based Building Materials. , vol.45 Springer, pp. 212-231. 10.1007/978-3-031-33465-8_17

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Earthen construction systems have potential hygrothermal, and environmental benefits over conventional building materials such as concrete. However, such systems are not yet fully optimised to be part of an energy-efficient building. Therefore, to further optimise the material, this review explores peer reviewed research articles that relate to different materials used in cob mixes and the different testing methods used to assess the produced specimen’s hygrothermal performance. For data collection, a systematic keyword search was carried out on ScienceDirect, Scopus, Google scholar search engines and relevant books. The filtering of journal articles was based on studying the abstracts followed by analysing their content within the scope of the review. The results show that the soil’s constituents and the added fibre ratios critically affect the percentages of clay and water added to the mixture. Fibres’ impact on the mix was experimented with by multiple researchers using distinct types of plant aggregates. The percentage of fibre addition ranged between 0.9% and 3% for structural specimens and reached 25% for non-structural specimens with optimised insulation properties. However, there is no consensus and robust collated data available about the ratios of the mixes concerning the hygrothermal performance of the specimens. Therefore, a matrix for mixes and testing methods was developed with the available data to aid the progression of any future optimisation efforts.

Item Type: Conference or Workshop Item (Paper)
Date Type: Publication
Status: Published
Schools: Architecture
Subjects: N Fine Arts > NA Architecture
T Technology > TA Engineering (General). Civil engineering (General)
Uncontrolled Keywords: Earthen Construction, Mixing Ratio, Hygrothermal Testing, Cob
Publisher: Springer
ISBN: 978-3-031-33465-8
Date of First Compliant Deposit: 21 July 2023
Date of Acceptance: 2023
Last Modified: 21 Aug 2023 01:30

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