190 coring is conducted in key abnormal sections to obtain direct parameters for engineering design. Then, multi-borehole detection data are fused to construct a three-dimensional geological model ahead of the working face through data inversion, enabling macroscopic identification of fractured zone distribution, graded prediction, and precise evaluation of water richness, fragmentation degree, and water inrush risk, providing a reliable basis for grouting treatment schemes. 3.3.3 While-Drilling Exploration and Geological Identification Technology Centered on the "two-step" precise grouting process, this technology integrates special equipment and adaptive materials to ensure grouting treatment effects. 1)“Two-Step” Grouting Process When lost circulation or borehole collapse occurs during drilling, forward segmented grouting is implemented to protect and reinforce the borehole wall. Then, a perforated casing is installed, and segmented reinforcement grouting is conducted using slurry stoppers within the casing to form a long-term water-blocking and reinforcement curtain, as shown in Figure 4. Figure 4 – Sectional grouting with perforated pipe schematic diagram 2)Downhole Segmented High-Pressure Grouting Technology Based on the characteristics of different strata, differentiated segmented treatment strategies are implemented. The treatment section length is set to 30–80 m for fractured strata, 20–30 m for broken strata, and 5–10 m for extremely broken strata. One-way perforated casings and specialized high-pressure slurry stoppers with a pressure-bearing capacity of 35 MPa are developed to achieve high-pressure segmented control, ensuring repeatable and reliable sealing at any position within horizontal boreholes. 3)Highly Adaptive Grouting Materials A series of grouting slurries is developed to accommodate complex geological conditions. Modified cement-based materials are suitable for permeation reinforcement in fractured strata. High-solid-content and high-fluidity cement-based materials are applied for splitting and compaction in argillized zones. Clay–cement slurry is utilized for long-distance
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