###### Abstract  
The application of new materials for soil stabilisation is a growing field of study in recent years. In this work, the effect of two types of silica-based nanomaterials combined with binders (quicklime and cement) are studied to stabilise soils and form structural layers for rural and low volume roads. The physical and chemical properties of the materials have been determined, as well as the mechanical behaviour of the stabilised soil. Three hybrid stabilised soil sections have been designed using a multilayer elastic model, executed at full scale and measuring the evolution of their properties in the medium to short term. The results show that the application of silica-based nanomaterials and two types of binders on the tread layers provide high structural stability and good behaviour of the sections. hybrid stabilisation; mechanical behaviour; real scale application; nanomaterials Article  
Facilities: No: MDPI stays neutral  
Soil Solution in Rural and Low-Volume Roads  
J.R.G.M., J.R., J.R., J.J., F.R., J.  
use in civil engineering applications, soil stabilisation for application in road layers has become widespread in recent years [6; 7]. Soil stabilisation is defined as the improvement of the shear strength, durability stiffness and reduction of the plasticity and swelling potential of soils achieved by mechanical means or the addition of stabilising products, such as a hydraulic binder, fly and rice husk ash, chemical stabilisation, recycled waste and by-products, etc. [8]. Among all the stabilising products, stabilisation with binders (commonly lime and cement) have been widely used by numerous authors in recent decades [9; 10; 11; 12]. Nevertheless, the production of these traditional materials generates a negative environmental impact due to the use of raw material resources and the high CO\({}_{2}\) emissions involved in their production [13]. For the reason mentioned above, in recent years, several studies that analyse the possible stabilisation of soils with industrial by-products or recycled materials, such as biomass fly and bottom ash [14; 15; 16; 17], phosphogypsum [18; 19], steel slag [20; 21] and magnesia oxides [22; 23], among many others, have been increased. In addition, in recent years, an alternative to conventional stabilising products and wastes and by-products has emerged: nanomaterials. Nanomaterials are particles with a typical size of between 1 and 100 nm, with a very high specific surface area, which implies a very high reactivity [24], achieving soil improvements with very low dosages. Nanomaterials commonly used in soil stabilisation are composed of simple oxides, such as SiO\({}_{2}\), TiO\({}_{2}\) or CaCO\({}_{3}\), or carbon nanotubes [25; 26]. Although a large number of nanoparticles has been developed, the pozzolanic capacity of Nano-SiO2 and its reactivity with lime and cement to form calcium silicate hydrate (CSH) compounds have led most studies to focus on it [27; 28; 29; 30; 31]. [PERSON] et al. [27] studied the effect of using synthesised Nano-SiO\({}_{2}\) by a sol-gel process together with cement to stabilise clay soil, concluding that a 7% addition of nano-SiO\({}_{2}\) improves the unconfined compressive strength in a ratio of 5:24 and reduces the permeability in the range of 0.01976 cm/s-0.01198 cm/s of the soil, which is consistent with previous studies [28]. [PERSON] et al. [30] and [PERSON] et al. [31] studied soil stabilisation with cements and nanosilane with dosages lower than 1% by weight of Nano-SiO\({}_{2}\), observing an increase in the unconfined compressive strength in all the mixtures with nanoparticulate additives and a high formation rate of calcium silicate hydrate (CSH), which implies an improvement in the soil properties. The present study shows new structural solutions for rural and low-volume roads based on soil stabilised with organosilanes and small amounts of lime and cement.