## 1 Introduction  
Monotonic loading of loose, saturated sand deposits may lead to the abrupt loss of shear strength and, as such, continues to be one of the most challenging problems in ground engineering [1, 2]. The sudden strength loss that occurs for undrained conditions is also known as static flow or softening [3, 4] and takes place before the effective stress path reaches the failure line. Static flow can have catastrophic consequences in natural and engineered earth systems, such as debris flow in sandy hillslopes. Fine particles in the sand can influence the likelihood and extent of softening, and has received extensive attention; seminal 20 th century contributions, include [5, 6, 7, 8]. Nevertheless, the role and implications of fines in loose sands remain somewhat disputed. For instance, [PERSON] et al. [9]reported on the formation of fresh collapsible structures in the sand upon the addition of non-plastic fines. [PERSON] and [PERSON] [10] had reported similar observations, but limited these unwelcomed skeletal structures to certain fines/sand ratio. Contractive response and flow in composite geomaterials were described in earlier works, including [8]. These tied in with reported cases of diminished strength in silty sands [6]. The unwelcomed impacts of the fines content were debated in [11], where the addition of up to 40 wt.% of silica silt to Ottawa Sand was found to reduce the rapid shearing-induced collapsibility. [PERSON] [12] subsequently reported a substantial reduction in brittleness for sands with 2.5 wt.% fines provided that the fines content was non-plastic. A series of more recent investigations have followed, which demonstrate the dependency of stiffness, yield, and the post-yield response of composite granular soils on fines content [13], packing state, as well as the fines' physicochemical properties [14; 15; 16]. In making provision for establishing or extending the built settings on loose sands, research into binary geomaterials (saturated sand with various fines contents for the present investigation) led to the development of a diverse range of chemical stabilization techniques. These techniques share uncertainties inherited from the contradictory views on the impacting role of the fines content in sand. Chemical stabilization often causes significant disturbances that include altering the soil structural composition and/or physical properties, changing groundwater flow pathways, modifying the thermal properties of the ground, changing the soil mineralogical composition, and altering geochemical conditions. Furthermore, chemical stabilization invariably disrupts the soil biogeochemical cycles that emerge from the exchange and transport of matter and energy, which are driven by the interaction of the living organisms in the soils, a perspective currently often overlooked by the engineering profession. Among the plethora of chemical agents, siliceous-based grouts have minimal detrimental effects on ground functions. Hydrated sodium silicate (Na\({}_{2}\)O\({}_{n}\)SiO\({}_{2}\), 0.06-0.203 g/cm\({}^{3}\) density) was employed by [PERSON] and [PERSON] [17] for stabilization of five sands of diverse gradations, with emphasis on the role of sand relative density (\(D_{\mathrm{r}}\)--that is, a packing proxy parameter) on strength of the composites. In examining the reduction in erodibility of standard-Proctor compacted medium silica sand for treatment using 1-4 wt.% NS additive of 11-13 nm particle size, [PERSON] et al. [18] reported a six-fold improvement in hydraulic erosion resistance for the optimum performing concentration of 1.5 wt.% NS achieved after a remarkably short one-day curing. [PERSON] et al. [19] used a low-viscose solution of colloidal silica (4 wt.% silica), with mean particle size, \(D_{50}\), of 10 nm, to stabilize poorly-graded Toyoura sand (\(D_{50}=0.2\) mm) for demonstration of the remarkable role of nano-particles in eliminating liquefaction and collapsibility potentials investigated under cyclic torsional stress conditions. [PERSON] et al.