The observation of the rock movement with voltage and AE after blast excavation

Shizuoka the third tunnel construction on The New Tomei Expressway

Abstract

The movement on the way to make ground arch inside the tunnel after excavation has been regarded as what offers the most appropriate data to grasp the balance of ground and tunnel support of NATM. Generally, we have been surveying the displacement of inside cross-section with a displacement seismograph in the ground and also the stress of tunnel support at a crown or side walls.
Now we have used the rock displacement and the stress of tunnel support to estimate the stability of the structure. At Shizuoka the third tunnel on the New Tomei Expressway, we have used various parameters like change of voltage, temperature and AE after excavation.
We report the result of the field test about the method we have never applied to the tunnel and the possibility of the assessment with this analysis.