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Abstract Deformation characteristics of surrounding rock and stress distribution of deep gob-side entry retaining，which was located in the first coal mine of Xiejiaji，the Huainan coal mining area，were analyzed by means of numerical simulation. The underground test for the deep gob-side entry retaining was introduced in detail，including the designs for primary supporting in the entry，additional enhanced supporting，and supporting beside the entry，and the monitoring data during various stages from driving，retaining to reusing. The supporting effects were evaluated through the analysis of the data of surrounding rock and backfilling body displacements and the loads along bolts and cables. The underground practice points out that the severe surrounding rock deformation in the deep gob-side entry retaining can be effectively controlled；and its stability can be kept by means of the synthetic supporting system，which consists of the high pretension and intensive bolts and cables as the primary supporting in the entry，individual props with articulated roof beam as the enhanced supporting，and paste backfilling as supporting beside the entry. On the basis of the research achievements obtained from numerical simulation and field test，the relationship between the primary supporting in the entry，additional enhanced supporting and supporting beside the entry were discussed；the great differences between deep and shallow entries on the breaking position of main roof，its rotation，and long-term creep of surrounding rock were indicated；and the supporting design criteria for the deep gob-side entry retaining were put forward. The improvement suggestions were also made in accordance with the existing problems in underground test.
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Received: 12 May 2010
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2010, Vol. 29 
