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Abstract Support selection is the key to application of advanced support technology with hydraulic support in gateways of coal face. Taking the selection of advanced hydraulic support in gob-side entry of working face 1302 in Xinjulong Mine as engineering background，the difference between the side strata structure of gob-side face and that of primary face is discussed；and the relationship between support and surrounding rock in gob-side entry of fully mechanized caving face is studied. Based on the moment equilibrium relations，mechanical model for determination of advance support strength in gob-side entry is established；and the viewpoint that strata rotary angle is the control object is proposed. Prediction of surrounding rock deformation of the gob-side entry is constructed by using displacement state equation of basic roof. Bearing capacities of coal pillar and solid side of the gob-side entry are calculated using the elastic mechanical theory. With the principle of squeeze nonoccurrence，the conclusions that the critical rotary angle of basic roof is 2.7°and the critical strength of advance support in the gob-side entry is 0.50 MPa are obtained. The advanced hydraulic support of ZTC30000/25/50 type is selected according to the results. Finally，the reasonableness of the support is verified by using observation result of surface displacement of the gob-side entry. The results can provide a reference for determination of reasonable strength of advanced support and support selection.
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Received: 17 May 2012
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2012, Vol. 31 
