Technology of bolt-shotcreting-grouting combined support to mine large cross section chamber

in order to solve a high tificult suppot and seriaus deformation problems of the large c1oss section winch chamber,based on a winch chamber in the three levelrail roadiway of Zhnongta ine as a studly objecta FLAC3 Dsotiware wa appied to analjze the surounding rock stability of the winch chanber under the bot and anchor combined support and the bofi-shotcreting-grouting combined suppor and a ite est was conducted on the bol.-shotcreting-grouting conmbined sup.ortechoology;.The stuty results showed that under the condition of thebot and anchor combined support.the two foor angles of the chanier woul be sufered ith high horzontal tresse.,the verial tress would concentrated on the foo of the chanmber and tus those were the causes of the J type steelfalre and the foor heave under thecondition of the previous supportWih the bofi- shotcreting-grouting combined support technolgyeach direcion stress of the surounding rock inthe chamber was reative homogeneous.the convergence of the two sidewal s in the chanmber was 43 m,the convergence of the roof and foor was 2 1 m and the surounding rock deformation of the chamber was effectively controlled.