The design and construction of gravel tunnel and rock tunnel are different. Rock classifications, such as CSIR-RMR method and Barton-Q system, are not suitable for the gravel tunnel.

• ?石隧道之??施工?岩石隧道有著明?的不同,如在岩?分?方面?o法使用岩石隧道常用的南非CSIR-RMR及挪威Barton-Q值之定量?估方法。