Installation of Bored Piles with a Protective Silicate Shell of a New Design in Saline Sility-Clayey Soils  
[PERSON]  
1 Department of Building Materials and Technologies, Karaganda State Technical University, Karaganda 100028, Kazakhstann, [EMAIL_ADDRESS]  
[PERSON]  
2 Department of Civil Engineering, K. Satyaev Ekbastuz Engineering and Technical Institute, Ekbastuz 141206, Kazakhstann; 91 [EMAIL_ADDRESS]  
[PERSON]  
3 Department of Civil Engineering, L.N. Gumilyov Eurasian National University, Nur-Sultan 010008, Kazakhstann; [EMAIL_ADDRESS]  
[PERSON]  
3 Correspondence: [EMAIL_ADDRESS]il.ru; Tel.: +7-707-850-3035  
strengthening with clay soils for noncohesive soils [3]. However, corrosion and, consequently, a gradual decrease in the bearing capacity of concrete structures in a chemically aggressive soil environment also have great impacts on subsequent operation.  
Corrosion-resistant materials for the surface protection of concrete structures, according to review studies of [PERSON] et al., 2017 [4] and [PERSON], 2021 [5], in terms of the mechanism of action, can be divided into four groups: surface coating, surface treatments, pore-blocking surface treatment, and hydrophobic impregnation. In terms of corrosion-resistant materials, they are subdivided to organic and inorganic based. The organic protection of a concrete pile by oil-bituminous rocks or natural bitumen is an efficient but labor-intensive and a short-service-life method [6; 7]. A number of scientists have presented surface coatings with inorganic materials: acrylic [8], polyurethane [9], polymer nanocomposite as a polymer-clay [10], polymer-silica [11], and epoxy resins [12].  
Hydrophobic impregnation, preventing the penetration of aggressive liquid through the pores of concrete, was implemented by incorporating nanoparticles [13; 14], micro silica [15], or stearic acid emulsion [16]. Increased hydrophobic coatings were also achieved by including ammonium polyphosphate [17], calcium carbonate nanoparticles [18], candle soot [19; 20], cyanoacrylates [21], and rise husk ash [22].  
The strategies of pore-blocking concrete surface treatment with fluosilicate [23], sodium silicate [24], and calcium silicate-based solutions [25] are some of the types of surface treatment of reinforced concrete structures. However, it should be noted that the high friction of soil particles increases the risk of surface abrasion, and the inability to control the integrity of the protective coating during the operation of the foundations complicate the technology of their application in deep foundations.  
As for the ground improvement, the samples treated with silicate cement [26], geopolymers [27], and fly ash and slag [28] have shown reliable results in terms of collapsible deformations under loading in wetting conditions and soil stabilization in general. Thus, based on the experience of previous research, including personal contributions of the authors in this area [29], it was required to develop a progressive corrosion protection method that meets the design requirements of an aggressive saline soil environment satisfying SP RK 2.01-101-2013 [30] and, at the same time, increasing the bearing capacity and durability of bored pile foundations:  
* Formation of a protective corrosion-resistant \"shell\" around the pile;  
Figure 1: Map of saline soils of Kazakhstan according to NTP RK 07-01.1-2011 [2]: (**1**) chloride and sulfate-chloride; (**2**) sulfate; (**3**) sulfate and chloride-sulfate; (**4**) gypsum salimization; (**5**) insignificant salinity soils.  
Formation of a compacted or ground-improved soil layer around the pile by increasing its strength and deformation properties, structural and suffusion resistance, and water resistance and waterproofness;
* Increasing the strength and corrosion resistance of the concrete of the structure by using modifiers, etc.