Scholarlink

<p>Deep underground coal mining in China faces significant challenges from geostress-induced hazards, including rockbursts and gas outbursts. The Pingdingshan mining area, characterized by complex fault-fold structures and depths exceeding 1000&#xa0;m, exhibits highly heterogeneous stress distributions, leading to frequent roadway instability. This study aims to quantify in-situ stress characteristics in the eastern Pingdingshan mines and establish engineering guidelines for optimizing roadway layouts to mitigate geostress-related risks. We analyzed 25 sets of in-situ stress data (440–1123&#xa0;m depth) from four mines (No.1, No.8, No.10, No.12) obtained via the stress relief method. Stress field types were classified using Anderson’s fault theory; regression models were developed to correlate principal stresses (σ₁, σ₂, σ₃) with depth; and lateral pressure coefficients (kₕ, kₐᵥ) were evaluated. FLAC3D simulations modeled stress evolution under varying angles (0–75°) between roadway excavation and maximum principal stress (σ₁) direction. Key findings reveal that: (1) 96% of measurements showed horizontally dominant stresses (tectonic field); 72% exhibited strike-slip fault regimes (σ₁ &gt; σ₂ &gt; σ₃), while 24% were reverse-fault-type (σ₁ &gt; σ₃ &gt; σ₂). (2) σ₁ and σ₃ increased with depth (σ₁ = 0.0418&#xa0;h + 2.936; σ₃ = 0.0193&#xa0;h + 3.3793) but displayed high variability (e.g., σ₁ = 43.56–65.46&#xa0;MPa at ~ 1100&#xa0;m). (3) kₕ ranged 1.48–2.8, confirming tectonic stress dominance; High-J₂ zones (&gt; 150&#xa0;MPa<sup>2</sup>) exhibit strong spatial correlation with reverse fault stress regimes and documented coal–gas outburst incidents. (4) σ₁ orientations vary regionally: SEE-trending in Pingdingshan No.1 Mine versus NEE-trending in No.8, No.10, and No.12 Mines, attributed to the influence of the Likou Syncline and Guozhuang Anticline. The regional tectonic stress direction is NE-trending, which was similar to the principal stress directions of the No. 8, No. 10, and No. 12 Mines. (5) Simulations revealed minimal stress concentration when roadways aligned with σ₁; The study present the first experimental validation demonstrating that when the intersection angle between roadways and σ₁ exceeds 60°, vertical stress concentration experienced a sharp increase of 15–20%, establishing a critical threshold for engineering optimization. Furthermore, a differentiated roadway layout strategy based on localized geostress orientations (SEE-trending for Mine No.1 and NEE-trending for other mines) is proposed, achieving integrated optimization of geological structures, stress fields, and engineering design.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Geostress Characteristics and Roadway Stability in the East Pingdingshan Mining Area

  • 期刊论文

  • 发表日期：

    2025年9月19日

查看全文
  • Weidong Gong,
  • Kunyun Tian,
  • Liuqun Du,
  • Ruilin Zhang,
  • Yinbo Zhou,
  • Yuanzhe Meng

摘要

Deep underground coal mining in China faces significant challenges from geostress-induced hazards, including rockbursts and gas outbursts. The Pingdingshan mining area, characterized by complex fault-fold structures and depths exceeding 1000 m, exhibits highly heterogeneous stress distributions, leading to frequent roadway instability. This study aims to quantify in-situ stress characteristics in the eastern Pingdingshan mines and establish engineering guidelines for optimizing roadway layouts to mitigate geostress-related risks. We analyzed 25 sets of in-situ stress data (440–1123 m depth) from four mines (No.1, No.8, No.10, No.12) obtained via the stress relief method. Stress field types were classified using Anderson’s fault theory; regression models were developed to correlate principal stresses (σ₁, σ₂, σ₃) with depth; and lateral pressure coefficients (kₕ, kₐᵥ) were evaluated. FLAC3D simulations modeled stress evolution under varying angles (0–75°) between roadway excavation and maximum principal stress (σ₁) direction. Key findings reveal that: (1) 96% of measurements showed horizontally dominant stresses (tectonic field); 72% exhibited strike-slip fault regimes (σ₁ > σ₂ > σ₃), while 24% were reverse-fault-type (σ₁ > σ₃ > σ₂). (2) σ₁ and σ₃ increased with depth (σ₁ = 0.0418 h + 2.936; σ₃ = 0.0193 h + 3.3793) but displayed high variability (e.g., σ₁ = 43.56–65.46 MPa at ~ 1100 m). (3) kₕ ranged 1.48–2.8, confirming tectonic stress dominance; High-J₂ zones (> 150 MPa2) exhibit strong spatial correlation with reverse fault stress regimes and documented coal–gas outburst incidents. (4) σ₁ orientations vary regionally: SEE-trending in Pingdingshan No.1 Mine versus NEE-trending in No.8, No.10, and No.12 Mines, attributed to the influence of the Likou Syncline and Guozhuang Anticline. The regional tectonic stress direction is NE-trending, which was similar to the principal stress directions of the No. 8, No. 10, and No. 12 Mines. (5) Simulations revealed minimal stress concentration when roadways aligned with σ₁; The study present the first experimental validation demonstrating that when the intersection angle between roadways and σ₁ exceeds 60°, vertical stress concentration experienced a sharp increase of 15–20%, establishing a critical threshold for engineering optimization. Furthermore, a differentiated roadway layout strategy based on localized geostress orientations (SEE-trending for Mine No.1 and NEE-trending for other mines) is proposed, achieving integrated optimization of geological structures, stress fields, and engineering design.