Multiphase assessment of post-mining effect on railway structures: A case study of Jharia Coalfield

• Published in: Journal of Earth System Science Vol. 132; no. 4; p. 154
• Main Authors: Prakash, Amar, Bharti, Abhay Kumar, Paul, Avinash
• Format: Journal Article
• Language: English
• Published: New Delhi Springer India 15.09.2023; Springer Nature B.V
• Subjects: Coal; Coal mining; Earth and Environmental Science; Earth Sciences; Electrical resistivity; Empirical analysis; Evaluation; Geophysics; Ground motion; Mathematical models; Modelling; Movement; Multiphase; Numerical models; Railway engineering; Railway tracks; Rock properties; Space Exploration and Astronautics; Space Sciences (including Extraterrestrial Physics; Stability; Stability analysis; Strata; Subsidence; Tomography; structures; stress; Subsidence; stability; resistivity
• ISSN: 0973-774X; 0253-4126; 0973-774X
• DOI: 10.1007/s12040-023-02169-z

Subsidence-associated damage to surface structures like railway tracks over old mine workings instigate catastrophic impacts on human lives. The complexity of investigating old mine workings pose challenges owing to unapproachability restricting visual access, incomplete historical plans, limited record information, etc. The crux in studying unapproachable areas circumscribes the ambit of in-depth research. Thus, the framework of the investigational approach has been addressed in three segments (subsidence investigation, geophysical investigation and coal pillar stability analysis) to gather additional records to culminate the safety of the railway track located above old workings. A subsidence investigation has been conducted for a period of 9 months to assess the present status of ground movement along the railway track. Integration of geophysical investigation led to evaluating the impact of old workings on the overlying strata that can lead to subsidence in the future. Electrical resistivity tomography (ERT) technique has been used to assess the status of old underground workings, which resulted in the identification of sub-surface void as well as overlying strata disturbance status. Numerical modeling using FLAC 3D , including the empirical method, has been undertaken to investigate the stability of coal pillars with respect to pillar dimensions and rock properties. The multiphase investigation resulted in arriving at a concrete understanding of the ground condition with respect to stability. Research highlights Stability of ground over old mine working was conducted by segmenting the investigation into three broad orientations i.e. by geophysical investigation to assess the ground movement status in the past, subsidence measurement for present ground status and empirical & numerical modeling for futuristic possibility of ground movement. Geophysical investigation was carried out to assess the ground movement status in the past. Subsidence measurement was conducted to evaluate for present ground movement status. Empirical and numerical modeling was conducted to estimate futuristic possibility of ground movement along railway line.