In tunnels, large deformation behaviour after excavation sometimes occurs without any warning except for inner deformation measurements such as convergence and crown settlement. Then countermeasures against the abnormal phenomena are obliged to adopt, which are selected based on engineers judgment without any detailed investigation. Judging from the site conditions, it is a matter of course that urgent countermeasures should be selected and the selected countermeasures are often proven to be effective. This is one of the reasons why experienced engineers are always necessary to difficult tunnel sites. On the other hand, important data such as inner deformation measurement results obtained with considerable efforts are often not available at tunnel site, because an estimation approach of field measurement results has not been established yet, which can offer easy understanding and useful information for the tunnel engineer. This paper demonstrates an example of estimation and feed back to design of the results of deformation measurement for a tunnel in squeezing rock by combined back analysis with ordinary design analysis.
In tunnels, larg …
AUTORI: Chikahisa H., Tsutsui M., Kumagai K., Sakurai S. RIG ANNO: 1999 NUMERO: 1 Numero di pagina: 78