## 1 Introduction  
Recently, researchers have been increasingly concentrating on utilizing paving blocks in infrastructure applications, thanks to their substantial benefits. Paving blocks are structural materials applied on hard surfaces, including driveways, pedestrian sidewalks, garden patios, and pool terraces [1, 2]. These blocks are formulated to withstand severe environmental conditions, including temperature variations, heavy rainfall, and freeze-thaw cycles, which can drastically shorten their lifespan or that of the concrete [3]. However, the large-scale use of cement in the production of paving blocks contributes to CO\({}_{2}\) emissions, as cement is recognized as the second largest industrial emitter and is projected to account for up to 23% of total emissions by 2050 [4]. This ecological impact has motivated researchers to find suitable solutions by appropriately opting for sustainable alternatives to traditional cement [5]. Among these alternatives, a broad range of ashes such as municipal solid waste incineration bottom ash (MSWI-BA) [6; 7], corncob ash [8], bamboo leaf ash [9; 10], date palm ash [11], and rice husk ash [12] have been explored thanks to their pozzolanic features and environmental effectiveness. Previous attempts to integrate rice straw ash into pavement systems--specifically payer blocks--have convincingly demonstrated the potential of agricultural ashes in such applications [3]. Rice straw ash's capacity to preserve structural integrity and stability reinforces its suitability for these purposes [3]. Olive waste ash (OWA), produced from the combustion of olive pomace, has attracted interest as a locally available agricultural byproduct in Mediterranean areas [13; 14; 15; 16]. The annual quantity of waste generated from olive crops is estimated at approximately three tons per hectare of olive orchards, resulting in biomass production of about 3.3 \(\times\) 10\({}^{7}\) tons [17]. Compared to cement production, the combustion of pomace used as a biofuel for energy purposes results in lower CO\({}_{2}\) emissions [18]. According to a study conducted in an olive pomace plant in Greece, the combustion of pomace used as biofuel instead of traditional fossil fuels can save about 9100 tons of carbon emissions [19]. Additionally, there are a variety of types of olive waste, including olive stones used for thermal insulation in a mortar [20], olive kernel shells implemented for self-compacted lightweight mortar [21], and olive wood waste applied in masonry blocks [22]. Similarly, OWA has been potentially applied in several sectors, including concrete, geopolymers, soil stabilization, embankments, and brick manufacturing, to limit the detrimental effects of cement and dispose of unused residues. The results of a prior study highlight that employing OWA reduces the compressive and flexural strength of cement paste [23]. For instance, the addition of OWA tends to decrease the 28-day compressive strength from 27.44 to 16.41 MPa and the 28-day flexural strength from 8.89 to 4.81 MPa, with varying OWA content from 0% to 15%, respectively [23]. On the other hand, replacing cement with 10% OWA substantially boosts the durability of the cement paste [24]. This improvement is associated with a reduction in all length change parameters--whether shrinkage or expansion--thereby strengthening its resistance to cracking [24]. The widespread accumulation of waste has brought massive pressure on the ecosystem. Nonetheless, a significant portion of the unused waste is considered pozzolanic resources, which are frequently applied in construction activities. Partially replacing traditional cement with pozzolanic materials helps to reduce the tremendous amount of residue and its ecological impact. As known, pozzolanic materials are natural or industrial resources essentially consisting of high amounts of silicon dioxide or silica (SiO\({}_{2}\)) and aluminum oxide or alumina (Al\({}_{2}\)O\({}_{3}\)) [23].