In the rapidly evolving landscape of today's world, the importance of efficient waste management and minimising waste may not be overstated for the effort of sustainable development [1], [2], [3]. The environmental problem resulting from limestone mining waste poses a serious threat to both ecological harmony and societal well-being. Quarrying, a critical economic driver in numerous countries, including Palestine [4], generates an extensive volume of waste through stone production, which leads to pressing environmental consequences necessitating immediate action. The demand to find solutions that maintain environmental preservation while fostering sustainable growth is essential [5]. The waste that results from stone shaping processes is especially alarming [6], but there is a bright side: this waste is creatively recycled to be used in construction projects. This process produces environmentally friendly building materials while also paving the way for sustainable practices [7], [8]. Due to the sector's rapid expansion and the limited supply of natural river sand, a crucial ingredient in building activities, the construction industry has recently faced significant challenges [9]. River sand, predominantly silica (SiO2) with a distinct grain shape and texture, is now in very limited supply, raising various environmental alarms [10]. The limited availability of river sand resources has triggered a quest for alternative materials capable of substituting natural sand in construction to some degree or entirely [11]. In response, the industry has examined numerous substitutes for natural sand in building applications [12]. One innovative alternative is utilising limestone, a residue of quarrying activities, as a practical substitute for river sand [13]. The environmental advantages of replacing traditional river sand with quarry waste are comprehensive, spanning from reducing landfill needs to protecting ecosystems and the health of surrounding communities [14].
The increasing concerns for environmental preservation and the necessity for sustainability underscore the importance of recycling solid waste without delay [15]. The study in [16], delves into exploring groundbreaking materials that could serve as alternatives to the traditional sand employed in construction, aiming to reduce the environmental impact. The cement-concrete composite stands as the dominant material in engineering worldwide, favoured for its superior qualities and cost efficiency [17], [18]. Despite its intricate multi-component nature, various processes, and detailed specifications, the production methodology for concrete is relatively straightforward, as documented in several references [19], [20], [21], [22], [23]. In concrete, aggregates—both fine and coarse—occupy a significant volume, ranging from 60–75%, playing a pivotal role in defining its physical and mechanical properties [24]. In particular, fine aggregates, which make up about 35–45% of the total aggregate volume, are needed to fill in the voids between coarse aggregate grains, making the bond in standard concrete denser and stronger [25].
Numerous studies have delved into the viability of utilising quarry waste materials in construction without affecting the integrity of the cement mixture [26]. Humayun et al. [27] found that incorporating quarry waste as a partial replacement for fine aggregate in concrete significantly enhances its compressive strength. Research consistently demonstrates that quarry waste, when used as a fine aggregate in concrete, can markedly improve various critical concrete properties [28], [29], [30], [31], [32], [33], [34], [35]. Such findings are crucial for the construction sector, offering a path towards environmental sustainability by recycling waste materials to enhance the strength, durability, and performance of concrete structures.
The construction industry's recent growth has encouraged extensive research into the development of sand concrete (SC), spotlighting it as a vital material for incorporating quarry waste [36], [37]. Its composition benefits greatly from the inclusion of fine aggregates, facilitating the use of waste materials. Gadri and Guettala. [38] observed that sand concrete, when made with crushed limestone sand instead of traditional river sand, satisfies the necessary physical and mechanical standards. Furthermore, substituting limestone sand in sand concrete significantly improves its mechanical properties [39], [40]. Jaradat et al. [36] analysed the microstructure of sand concrete with limestone sand and discovered enhanced compactness in its composition, marking a pioneering step in sustainable construction practices within the sector by promoting the recycling of quarry waste.
The mechanical properties of concrete, such as tensile strength, compressive strength, flexural strength, and modulus of elasticity, are essential metrics for evaluating its behaviour under various loads and environmental conditions [41], [42], [43], [44]. Tensile strength determines the concrete's capacity to resist tensile (stretching or pulling) forces, whereas compressive strength measures its ability to withstand compression. Flexural strength evaluates the concrete's resistance to bending or flexing stresses, playing a critical role in determining the material's overall structural performance.
In addition, the modulus of elasticity, indicative of concrete's stiffness or flexibility, offers insights into its deformation response under stress and its ability to revert to its initial form upon stress removal. These mechanical characteristics are foundational in the architectural and analytical processes of concrete structures, aiding engineers and scholars in making well-informed choices about material utilisation, structural configuration, and performance evaluation. The physical attributes of aggregates, such as their form, size, and pre-mix treatments, are instrumental in defining the ultimate properties and efficacy of the concrete mix. Drawing from a considerable volume of research [45], [46], [47], [48], [49]. it is evident that aggregates significantly impact the concrete mix by imparting crucial qualities. The dimension and shape of aggregates critically affect the concrete's workability, durability, and reliability, underscoring their importance in the mix's composition and performance outcomes.
This study aims to explore the reuse of quarry waste, specifically in the form of limestone sand, to enhance the attributes of sand concrete, thereby mitigating the environmental impact associated with quarry waste disposal. Through an extensive series of evaluations, this research will investigate the physical and mechanical behaviours of sand concrete as the limestone sand content varies from 0–70%. The assessments will encompass a variety of tests, such as density, compressive strength, flexural strength, ultrasonic pulse velocity (UPV), dynamic elastic modulus, and microstructure examination, to comprehensively understand the implications of incorporating limestone sand into sand concrete.