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Abstract Determination of the reasonable width of pillars between roadways is the key for ensuring safety production of large mining height face with double roadways layout. Taking the double tunneling pillar between haulage gate and gas drainage roadway of 204 large mining height face in the second panel of Tingnan Coal Mine as the engineering background，firstly，the failure regularity of pillar between roadways under the effect of double tunneling and two times mining was systematically studied by using the method of field stress monitoring. A 3 m wide of fractured zone near the gob was found，and a 18 m wide low stress zone was realized. The distribution curve of stress in pillar between roadways after the first mining was asymmetric. After the second mining，distribution curve of stress in pillar between roadways was like a asymmetric “saddle”and the cumulative broken at the edge of pillar was more than 9 m. at the same time，the division of pillar between roadways was given after the two times mining，and the reasonable width of pillar between roadways was determined preliminarily to be 5.2—13.0 m. Secondly，the stress evolution law，the elastic-plastic region variation，and the roadways deformation law of 5 different coal pillar that width of 4 m，6 m，8 m，10 m and 12 m were studied by numerical simulation. Various elements such as safety production and resources recovery were considered comprehensively. The reasonable width of double tunneling pillar between roadways in large mining height face was 10m. Finally，the reasonableness of the pillar width was verified by engineering practice. The results can provide a reference for the setting of pillar between roadways with similar mining conditions.
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2015, Vol. 34 
