The traditional new Austrian tunneling method (NATM) is introduced. From the NATM we know that maintaining the stability of surrounding rockmass must fully utilize and mobilize the strength of surrounding rockmass and its carrying capacity

and depend on co-action mechanism of the surrounding rockmass and support. We study the mechanism of bolt-netting

and setup the mechanic model of high strength and prestressed bolt. We find that the anchor strength of high strength and stressed bolt is related to property of surrounding rockmass

the anchor mode

staff of bolt and the stress of surrounding rockmass

etc. Meanwhile we analyse the co-action mechanism of bolt-netting support and surrounding rockmass

and apply FLAC to study the mechanism of bolt-netting support

and find that the bolt-netting support and surrounding rockmass come into the compressing arch. The roadway depends on the compressing arch resisting the surrounding stress

and maintains the stability of the surrounding rockmass. The deformation and destruction of surrounding rockmass is very serious. By scene test at 41 connecting roadway in the Xiaoguanzhuang Iron Mine

the deformation of roadway is small; the bolt-neting support can maintain the stability of high-stress and fragmented rockmass. The bolt-netting support has the extending and applying value at the similar metal mines.