Civil Engineering October 2022 | Vol 30 No 9

36 October 2022 Civil Engineering T he well-being of heritage structures is the priority of the Department of Sports, Arts and Culture, which is represented by the South African Heritage Resources Agency (SAHRA). This agency performs tasks including permitting heritage alterations such as conservation and restoration. SAHRA oversees the health monitoring and protection of her- itage sites, structures and archaeological objects, among many others. However, SAHRA and many other heritage authorities face a challenge when restoration must take place on structures of historical significance (Loke et al., 2021a, b). The main concern is the inap- propriate conservation and restoration of these structures. It originates from a lack of a systematic methodological approach for carrying out original material charac- terisation (Loke et al., 2020). Additionally, the use of incompatible restoration materials (such as Portland cement in most cases), techniques, and practices have led to disappointments in many restoration projects (Arizzi, 2012). Most repairs need to be revised after a few years of service due to sudden failures caused by inappropriate identification of the cause of failures and the application of materials portraying different properties to the original (Arito, 2018). A NEW APPROACH With this being the case, the Department of Civil Engineering and Geomatics at the Cape Peninsula University of Technology (CPUT), represented by the office of the Research Technology Innovation and Partnerships (RTIP), and SAHRA have formed a collaboration to work on the sus- tainable restoration of heritage structures. The research around heritage restora- tion in South Africa started in 2018 with a master’s project executed by Maphole Loke, a PhD (civil engineering) candidate and student coordinator at CPUT, and a can- didate engineering technologist. The work was centred around initiating the concept of original materials characterisation before carrying out restoration work on heritage buildings and developing a guideline for characterising heritage mortar. This research provides heritage practitioners and the heritage society with a more appropriate approach to heritage restoration as well as an understanding of the need for a multidisciplinary approach that involves civil engineers, geologists, historians, archaeologists, and chemists, among others. The project has received attention from abroad, mainly because Europe has advanced further than Africa on the topic of heritage restoration. A research collaboration has since been developed between the Department of Mineralogy and Petrology at the University of Granada, Spain and the Department of Civil Engineering and Geomatics at CPUT for designing and developing compatible restoration mor- tars for the Castle of Good Hope and the buildings on Robben Island, located in Cape Town, South Africa. In addition to the milestones for the ongoing project, the research is gaining international recognition. It was the only one of its kind from the African continent to be presented at the 12th International Conference on Structural Analysis of Historical Constructions in 2021. The research was initiated in 2018 by Professor Kumar Pallav and Adjunct Professor Rainer Haldenwang and has gained traction and seen great developments since collaboration began with Professor Giuseppe Cultrone, an expert in historic brick and mortar from the University of Granada. These collaborations have added significant value to this project and thus civil engineering contribution to heritage restoration. Additionally, the African World Heritage Fund supports the need to design and develop sustainable restoration mortars, funding this project through the Moses Mapesa Research Grant. The procedure for compatible restora- tion of historic mortars in this research involves the aesthetic analysis (colour description) of originally extracted mortar samples using a colorimeter, physical analysis through mercury intrusion H i story and her i tage Sustainable restoration of local heritage structures: an engineering approach Maphole Loke PhD candidate Cape Peninsula University of Technology lokemaphole@gmail.com The heritage history of the South African construction industry lies in the survival of heritage structures. Many of these monuments represent South African political history, religion and architecture throughout the centuries. But, with the changes in global behaviour, natural and human factors mean these structures face deterioration which threatens their existence. The Castle of Good Hope, Cape Town (Source: Leo za1 , CC BY-SA 3.0)