Hydraulic sand stowing is considered as an effective means of strata control and is widely practised in underground coal mines across the globe following coal extraction. In hydraulic sand stowing, barricades are used to contain the flow of sand after it is filled in the mined out site to be stowed in the form of sand-water slurry. Most commonly, these barricades are made of bamboo mats supported by a row of wooden props. As per the current practice, the timber props are left as such in the goaf and lost forever in the stowed area. Considering the prevailing environment and economic concerns with such high consumption of timber, the need to replace the conventional wooden support system with an alternate support system in this field has been felt by the mining industry. This paper illustrates the development of a reusable support system utilizing retrievable telescopic iron props as an alternative support for barricades used in hydraulic sand stowing operation. The salient features of the newly developed telescopic prop and a case study depicting its trial use in hydraulic stowing at Digwadih collieiy, Jharia Division of Tata Steel Ltd. are also elucidated in this paper. In addition, the paper describes the method of use, material requirement and cost analysis of the newly developed alternate support system for hydraulic stowing barricades. This study suggests that the use of telescopic iron props reduces timber consumption by 71.4% and the cost of barricading can be cut by 53.6% and hence if adopted it will definitely be beneficial for the coal mining industry and the environment.
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