A Dynamic Evaluation of the Tunnel with Structural Defects in Lining and its Countermeasures


Toshihiro ASAKURA,@Yoshiyuki KOJIMA,@Yutaka SATO,
Kazuhide YASHIRO,@Toyohiro ANDO

@Most tunnels have structural defects, like lack in thickness of a lining at a crown and presence of an opening behind the lining because of the construction technique applied. Model tests and frame analyses are carried out to know effects of defects on the lining and the countermeasures such as backfill grouting on the tunnel lining and an inner reinforcement with following conclusions drawn. 1)The strength of the tunnel with defective lining is much smaller than that without defect. 2)The strength of the tunnel recovers with execution of countermeasures.