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@article{203694,
        author = {Er. Gouri A. Mhetar and Tejas Sanjay Kadam and Aditya Narayan Velhal and Prem Baban Pandhare and Rohan Suresh Kadam and Aryan Sagar Jadhav and Omkar Anandrav Khot},
        title = {Soil Property Assessment For Drilling Fluid In Trenchless Technique HDD In Black Cotton Soil},
        journal = {International Journal of Innovative Research in Technology},
        year = {2026},
        volume = {13},
        number = {1},
        pages = {88-93},
        issn = {2349-6002},
        url = {https://ijirt.org/article?manuscript=203694},
        abstract = {The rapid acceleration of urban infrastructure development in India has significantly driven the demand for underground utility networks, including water distribution grids, sewage systems, gas pipelines, and telecommunication lines. Traditional open-cut excavation methodologies present severe socio-economic and engineering challenges, such as heavy traffic disruptions, environmental hazards, noise pollution, and exorbitant pavement restoration expenses. To mitigate these surface disruptions, trenchless technologies, specifically Horizontal Directional Drilling (HDD), have emerged as an efficient and sustainable paradigm shift in subsurface engineering. However, the mechanical safety and long-term success of HDD operations are highly dependent on the complex geotechnical characteristics of the subsurface strata encountered along the arched drilling catenary path. This project, titled "Soil Property Assessment for Trenchless Horizontal Drilling in Black Cotton Soil," focuses on executing a rigorous geotechnical evaluation of highly challenging, moisture-sensitive formations. The empirical framework of this research contrasts two distinct geological environments in Maharashtra: an inland expansive zone at Sangli-Madhavnagar dominated by deep weathered basaltic Black Cotton Soil (BCS), and a highly dynamic coastal-marine interfacial zone at Mumbai-Uran (Pirwadi Beach) characterized by shifting sand-clay stratification. During active field monitoring of tractor mounted HDD rig operations, cutting discharge spoils were manually extracted from slurry containment pits using traditional shovels (Khor) and transport basins (Pati) into high-density polymer sacks (Potya) to preserve structural particle distribution and moisture frames for laboratory transition. Advanced laboratory characterization was carried out at the Geotechnical Engineering Laboratory of D.Y. Patil College of Engineering and Technology (DYPCET), Kasaba Bawada, Kolhapur, strictly conforming to IS: 2720 (Part 5) standards. The experimental program systematically evaluated the consistency limits— Liquid Limit (LL) and Plastic Limit (PL)—of the retrieved soil samples across four separate water-based sodium bentonite drilling fluid concentrations: 0% (Only Water), 5%, 7%, and 10% by weight. The experimental results revealed that progressive bentonite slurry contamination systematically expands the moisture storage framework, driving the index boundaries upward for both soils. The inland Sangli Black Cotton Soil exhibited classic high-plasticity clay (CH) milestones, with its native Liquid Limit of 82.50% and Plasticity Index (PI) of 43.35% jumping aggressively to an extreme threshold of 111.25% (LL) and 68.40% (PI) at the 10% bentonite limit. Conversely, the Mumbai coastal interface displayed poor native binding capacity and lower initial parameters (LL = 31.40%, PI = 9.18%) due to the high dominance of fine intertidal beach sand fractions. However, high-percentage bentonite contact introduced a noticeable cohesive effect, nearly doubling its liquid limit to 61.14% at the 10% concentration milestone. From a process engineering standpoint, these distinct behaviors reveal separate operational risk thresholds for trenchless project design. The highly cohesive, heavy clay matrix of the Sangli formation provides structural support to open borehole walls but poses heavy downhole risks of micro-fissure squeezing, bitballing on reamers, and intense rotational torque spikes as cuttings accumulate in the slurry. In contrast, the Mumbai coastal soil loses cohesion rapidly upon drying and remains loose and sandy, making it highly vulnerable to borehole washouts, fluid loss, and tunnel collapses under shallow intertidal water tables. To mitigate these site-specific challenges, this research highlights that a minimum drilling slurry concentration of 7% to 10% sodium bentonite modified with Carboxymethylcellulose (CMC) polymers is essential to control fluid loss, deposit a low-permeability stabilizing filter cake, and optimize axial pullback loads. Ultimately, the quantitative trends derived from this comparative case study provide a data-driven geotechnical framework to optimize cost-efficiency and operational safety for trenchless infrastructure deployments across expansive clay and variable coastal domains.},
        keywords = {},
        month = {June},
        }