## 1 Introduction  
The global production of cement in 2018 exceeded 4000 million metric tonnes and is responsible for a considerable portion of the world's CO\({}_{2}\) emissions, i.e., 0.8 tonnes of CO\({}_{2}\) per tonne of cement [1]. Given the considerable amount of cement used to produce conventional concrete and the even greater amount for self-compacting concrete (SCC), necessary to reach its highly flowable state, there is considerable scope to reduce its content. With this in mind, along with the need to reduce the exploitation of the raw materials for clinker production, there have been several studies on the development of supplementary cementitious materials (SCM) [2; 3; 4; 5], which are typically by-products that re-enter the supply chain instead of landfill disposal thus preventing environmental issues such as the contamination of soil and groundwater.  
One of the characteristics that a product must exhibit to be considered as SCM is its pozzolanicity [3], wherein the aluminosilicates phases present must react with the hydrated cement's calcium hydroxide (Ca(OH)\({}_{2}\)) to form different phases including calcium silicate hydrates (C-S-H), which is responsible for most of the cementitious composites' mechanical performance. Examples of waste used as cement replacement in self-compacting concrete are: Rice ash [6]; sugarcane bagasse ash [7]; blast furnace slag [8]; and bottom ash from municipal solid waste (MSW) incineration [9; 10].  
Fly ash (FA), being a by-product of coal combustion in thermoelectric plants and traditionally used in SCC production, amounted to well over 350 \(\times\) 10\({}^{6}\) tonnes worldwide [11]. It is known that the replacement of part of cement by FA in the manufacture of self-compacting concrete improves the mechanical characteristics and durability of SCC [12; 13; 14; 15; 16; 17]. On the other hand, municipal solid waste (MSW) incinerator bottom ash (MIBA) corresponded roughly to 16 metric tonnes per year in the 28 State Members of the European Union [10]. Naturally, due to the high quantities generated and its direct relationship with population growth, there is a noteworthy challenge concerning the adequate management of the waste. Replacement of cement with this by-product in the manufacture of mortars and concrete has revealed the problem concerning the content of metallic aluminium in MIBA, which releases hydrogen upon reaction with water in an alkaline medium [18; 19]. The research developed by [PERSON] et al. [10], which presents a detailed review of the development of the compressive strength of concrete using MIBA up to a maximum replacement of 30%, demonstrated that there is no evident trend in the early ages of mechanical behaviour (<30 days). Some authors witnessed higher compressive strength when compared to the reference concrete (10% higher) and others with significant reductions (less than 50%).  
There are no studies in the literature wherein MIBA was used in the production of SCC, which is of particular interest to the industry given the phasing out of conventional FA due to the decommissioning of coal power plants. Therefore, this study intends to provide a way of disposal of MIBA, through its incorporation into ternary mixes of SCC as a cement substitute, by means of a laboratory campaign with several mixes in which the specimens are characterized in terms of their mechanical behaviour and durability. This research corresponds to a study of the CERIS R&D unit at Instituto Superior Tecnico, University of Lisbon, of a series of trials for the valorisation of MIBA.