Study on the sustaining effect of concrete-filled steel tubular supports in deep mining roadways
- PDF / 2,706,045 Bytes
- 14 Pages / 595.276 x 790.866 pts Page_size
- 66 Downloads / 216 Views
ORIGINAL PAPER
Study on the sustaining effect of concrete-filled steel tubular supports in deep mining roadways Xiang-song Kong 1 & Ren-liang Shan 1 & Hong-hu Yuan 1 & Yu-hang Xiao 1 & Xiao-sheng He 1 & Tian-tian Bao 1 Received: 15 July 2019 / Accepted: 6 October 2020 # Saudi Society for Geosciences 2020
Abstract Coal production under deep mining conditions is jeopardized by the stability loss of mining roadways: their adequate support has become an urgent technological and economic problem. In this study, a concrete-filled steel tubular (CFST) support applicable to deep mining roadway was proposed, and the related stress state was theoretically analyzed. For a deep mining roadway, the numerical model based on the commercial FLAC3D software package was developed and used to calculate the deep mining roadway behavior with and without the proposed CFST support. Using the self-developed nested similarity simulation experimental system, the physical similarity model of a deep mining roadway was elaborated. The stability loss process in the unsupported roadway, as well as the sustaining effect of support on stresses, deformation, and collapse behavior of the surrounding rock, was investigated in depth. According to the Mohr-Coulomb criterion, the stability loss mechanism in deep mining roadways and the sustaining effect of the CFST support were explored from the perspective of the Mohr circle evolution. The results obtained strongly indicate that the CFST support exerts a strong radial sustaining force on the surrounding rock surface in a deep roadway, increasing its minimum principal stress and reducing the respective stress concentration. The resulting reduction of the Mohr circle diameter implies that the roadway under study remained under safe conditions below the failure envelope. Finally, the feasibility of the CFST support was validated via the field test, which proved the adequate control of stability of the surrounding rock in a deep mining roadway. Keywords Concrete-filled steel tubular (CFST) support . Deep mining . Surrounding rock deformation . Mining roadway . Model test
Introduction Currently, the average coal mining depth in China is about 700 m, while the maximum one has reached 1500 m (Kang et al. 2010; Mohammad and Ahmad 2016; Xie et al. 2015). Given this mining depth ever-increasing trend, the crustal stress increases steadily, horizontal crustal stress approaches or even exceeds the vertical crustal stress, and the portal pressure coefficient ranges from 0.8 to 1.1(Kang et al. 2015; Xing et al. 2018a). Moreover, deep rocks exhibit more inferior mechanical properties (Antonio and Yu 2016; Zhao et al. 2009). Responsible Editor: Murat Karakus * Ren-liang Shan [email protected] 1
School of Mechanics and Civil Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China
This results in frequently occurring cases of mining roadways’ stability loss (especially, in coal mining), which became a critical safety issue during coal mine production and require a significant amount o
Data Loading...
