Deployment of Continuous Miner (CM)-based mass production technology is gradually increasing in Indian coalfields for enhancing production and productivity from underground coal mines. Strata control is one of the major challenges during underground winning of coal. Generally, width and height of roadways/galleries in the CM based mechanised working is more (around 6 m) than those stipulated in the Coal Mines Regulations 2017 for conventional BPMM. The width and height significantly influence on stability of the surroundings a roadway. Further, underground mining in India is gradually shifting towards higher depth of cover where induced stresses driven shearing/fracturing of surrounding rock mass also influences on the stability of roadways. Instability of roadways encounter during formation of widened and heightened gallery. A number of injuries including fatal and loss of the natural resources reported in CM-based mechanised workings in Indian mines due to roof/side falls. The design of the support system in gallery and junction in mechanised workings is mainly done by available indigenous empirical approach which is based on gallery width and height up to 4.8 m and 3 m respectively with maximum depth of cover of 250 m. Further, an empirical approach developed considering diagonal line of extraction, whereas CM based working generally practice straight line of extraction which involved different strata mechanics near the line of extraction. The available indigenous approaches having various limitations and difficult to implement directly in CM based mechanised workings.

A fields study considering actual geo-mining details, laboratory, and numerical simulation is required for suitable design of applied support system for extraction of coal using the mass production technology. Field study is carried out during development workings in twenty-two CM panels in different geo-mining conditions in Indian coalfields and observed the performance of surroundings of gallery, applied support system, which was designed on the basis of numerical modelling study. The designed support system is found to be efficient to stabilize the gallery during the development working. Parametric numerical modelling is carried out considering the rock mass properties/reinforcement support details of the selected panels and variation of depth of cover, width of excavation, rock mass rating to estimate the rock load height at gallery and junction for development working. A multi-variable regression analysis is done and developed formulations for gallery and junction. It is verified with available empirical approaches and found to be a good resolution of its limitation.  Further, detailed comprehensive study is required for development of a suitable support design norms for development and the mechanised workings for safe and efficient recovery of coal using the mass production technology under different geo-mining conditions.