Innovative Silicate–Cement Injection Framework for Seepage Mitigation in Sandy Foundations: Optimized Mix Design, Strategic Application, and Integrated Project Management Perspectives

Abstract

Seepage through sandy foundations remains one of the most persistent and challenging problems in the construction, maintenance, and rehabilitation of hydraulic structures such as dams, barrages, spillways, and canal regulators. Uncontrolled seepage can lead to piping, internal erosion, and progressive structural instability, ultimately compromising the safety and operational efficiency of these critical infrastructures. Conventional cement grouting and sodium silicate injection techniques, while widely applied, often fail to achieve the desired permeability reduction and structural reinforcement in heterogeneous sandy soils due to their limitations in penetration, setting time control, and durability under variable hydraulic gradients. This research proposes an innovative silicate–cement injection framework that addresses these limitations through an optimized grout mix design, strategically oriented field application techniques, and integrated project management methodologies. The grout formulation combines Ordinary Portland Cement (OPC), sodium silicate, and selected chemical additives including accelerators, viscosity modifiers, and anti-washout agents to achieve a balance between low initial viscosity for enhanced penetration and rapid gelation for early strength gain. The mix is fine-tuned using laboratory trials to determine the optimal water-to-cement ratio, silicate concentration, gel time, and target viscosity range, ensuring adaptability to variable field conditions. Experimental investigations include permeability reduction tests, unconfined compressive strength measurements, setting time evaluation, and leachability analysis under simulated seepage conditions. Results show a permeability reduction of over 85% in treated sandy samples, a compressive strength improvement of up to 40% compared to cement-only mixes, and excellent stability against erosion under sustained hydraulic gradients. Additionally, scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses confirm the formation of dense hydration products and a robust interparticle bonding matrix. The application orientation is developed with a focus on systematic grout curtain construction through controlled drilling patterns, staged injection sequencing, and real-time pressure monitoring to prevent blowouts and ensure uniform material distribution. Pressure–flow rate optimization models are applied to maximize penetration depth while minimizing grout wastage. The project management component incorporates detailed planning and scheduling frameworks, quality assurance protocols, and risk mitigation strategies, including contingency plans for variable soil permeability and unforeseen field constraints. Cost–benefit analysis demonstrates that the proposed methodology offers significant savings in material and labor costs compared to conventional approaches, while also improving overall operational timelines. Field implementation on a pilot-scale hydraulic structure confirms that the integrated silicate–cement injection approach not only achieves substantial seepage control but also enhances the structural integrity and long-term durability of sandy foundations. The study concludes that the proposed framework offers a scalable, sustainable, and field-validated solution for seepage management, with strong potential for adoption in large-scale hydraulic infrastructure projects worldwide.