Research on key construction technologies of frozen shaft in ultra deep and thick alluvium

Zang Peigang; Wang Wei; Ma Hongqiang; Li Haipeng

doi:10.13199/j.cnki.cst.2017.08.016

Abstract：According to frozen drilling and support construction technology problem of main shaft in Wanfu Mine with 754.8 m ultra deep and thick alluvium,this paper studied and practiced the key techniques of excavation and support in Wanfu Mine freezing sinking engineering,including frozen wall stability,frozen soil tunneling technology,high performance concrete wall support.We used two methods to determine the time of excavation by calculating the pace of frozen soil development and measuring temperature of temperature-measuring hole.According to the design thickness and average temperature of frozen wall,we analyzed the frozen wall deformation.Based on the results,the safe height of section and exposure time were determined for excavation alluvium.The umbrella drilling rig with bolt head,twist drill rod and Y shaped drill were used to drill borehole in froz en soil.Inorder to solve the frozen soil drilling and blasting construction problems,This paper select the low temperature and water gel explosives,and preserved heat for explosive.A series of high performance concrete production and transport techniques were adopted to guarantee the quality of high performance concrete lining,such as gravel wash screen means,underground mine concrete transport system and underground mine concrete fixed points ash,especially steel fiber reinforced concrete lining in the deep freeze alluvium shaft support.