Research Article

Influence of Arch Foot Defect of Primary Support on Mechanical Behaviors of an Arch Frame in Underground Tunnels

Table 1

Monitoring parameters and instrument installation.

Monitoring itemsPhysical quantityInstrument nameSpecificationQuantity

Bolt axial forceBolt axial force gaugeMSJ5 measuring points
Concrete strainConcrete strain gaugeEM-307 measuring points
Steel rib stressRebar stress gaugeSTG-255 measuring points