Abstract: The 80 m level north-middle transport roadway in Xishimen Iron Mine is the only way to transport rock from the north mining area to the main system of the mine.The transport roadway is located in the pillar section of Mahe Mine.Due to the influence of mining damage,the deformation of the roadway is serious.Therefore,the mine has to reconstruct a bypass,but it needs to pass through the extremely unstable zone of surrounding rock such as broken and soft rock mass.Based on the support theory of loosening ring,this paper adopts the construction scheme of five combined excavation and support technologies,i.e.guniting reinforcement loosening ring,advanced inserting rod manufacturing artificial roof,artificial micro-vibration excavation,closely following metal arch support and hanging net shotcrete support,to improve the timeliness of surrounding rock support,control the deformation of roadway,ensure smooth passage of bypass,and at the same time,under similar surrounding rock conditions.Tunneling provides a new construction method.

Key words: Broken and loose soft strata, Loose ring support, Integration of excavation and support, Construction technique