## 1 Introduction  
Soil stabilization is a key practice in geotechnical engineering to enhance the mechanical performance of problematic soils like clays with low bearing capacity, high plasticity, and sensitivity to moisture changes [1]. Portland cement (PC) and lime are commonly used binders due to their effectiveness; however, their production entails high energy use and substantial greenhouse gas emissions. Producing one ton of cement emits about one ton of CO\({}_{2}\), contributing to nearly 8% of global CO\({}_{2}\) emissions [2]. Moreover, impacts such as groundwater pH alteration have prompted the pursuit of more sustainable alternatives [3]. In this context, various alternative materials have gained prominence, coming from industrial by-products or solid waste, such as fly ash, slag, residual limes, marble dust, and recycled construction materials, including glass powder, gypsum residues, and limestone waste [4]. These materials not only reduce the use of cement and associated costs but also promote the circular economy by reusing waste that would otherwise end up in landfills [5; 6]. Among these by-products, limestone powder waste (CLW) and other stone industry-related residues--such as marble dust--generated by the crushing, polishing, or cutting of natural stone blocks, have shown promising results in soil improvement. Various laboratory studies have demonstrated that their incorporation significantly enhances unconfined compressive strength (UCS) and reduces soil deformability, with increases of up to 88% in strength and reductions of 32% in deformation [7; 8; 9]. When combined with lime, strength can increase by up to 59% [10]. Moreover, their use has proven effective in reducing plasticity, improving dry density, and optimizing the volumetric behavior of clayey or silty soils [11]. [PERSON] et al. [12] demonstrated that the porosity/volumetric cement content ratio (n/Civ) can predict both UCS and small-strain stiffness (G\({}_{0}\)) in CLW-stabilized mixtures, providing a rational tool for the design of stabilized soils. On the other hand, recycled glass powder (GG) has been proposed as a sustainable solution due to its pozzolanic reactivity, which facilitates the formation of cementitious gels in alkaline environments. The use in expansive soil reduced plasticity by up to 80% and significantly improved compaction and strength. An increase of up to 240% in pre-consolidation pressure and a six-fold improvement in CBR was observed with 16% SLGP. The formation of C-S-H and C-A-H compounds strengthened the soil structure. The optimal dosage was 16%, achieving enhanced geotechnical properties and environmental sustainability [13; 14]. Studies have shown that mixtures including between 5% and 30% of GG can significantly reduce porosity and increase UCS and indirect tensile strength, with improvements of up to 56.8% and porosity reductions of over 50% [15; 16]. Furthermore, the porosity/binder ratio (\(\eta/B_{iv}\)) has been used to model mechanical behavior and mass loss during wet-dry cycles, providing an effective method to estimate the durability and strength of GG-stabilized mixtures [17]. Fine GG particles have also been shown to double the UCS of expansive clays and reduce the required thickness of subgrade layers in road structures by up to 63% [18]. Recycled gypsum (GY), derived from plasterboards, phosphogypsum, or flue gas desulfurization gypsum, has also been used as a stabilizing additive. Its calcium sulfate content facilitates cementation reactions in the presence of activators such as lime [19]. Although its use entails technical challenges--such as moderate solubility or the formation of expansive products under certain conditions--several studies have demonstrated its effectiveness in improving clayey soils by increasing UCS, reducing swelling, and enhancing volumetric behavior. For example, mixtures containing 30% GY and 4% lime have reached UCS values above 1.5 MPa, meeting the requirements for use as pavement subbase [19].