Umbrella Arch Nomenclature and Selection Methodology for Temporary Support Systems for the Design and Construction of Tunnels

摘要: This paper argues that there is a requirement for standardized nomenclature and selection methodology particular class of temporary support. The authors have chosen the term Umbrella Arch (UA) to define method support acts as pre-support installed during first pass excavation around above crown tunnel face. UA supports rock mass face predominately by transferring loading longitudinally through interaction surrounding ground condition. There are three categories UA. Categorization depends on type element used. These elements include: (1) Spiles; (2) Forepoles; (3) Grouted. can be further divided into 11 sub-categories quantified amount grout utilized in installation. justified employment each sub-category within an UA; this was created based experience comprehensive literature search included published papers well design reports. collection publications has resulted 141 permutations different varying weak difficult geological aid designers these conditions with basic concepts appropriate process Furthermore, other pre-existing charts empirical evidence create new tool, chart. Overall, hopes achieve creation international standard respect better understanding sub-category.