ABSTRACT:

Large scaled model tests were carried out to study the short-term deformation behavior of the arch-shaped tunnel which was constructed by cut-and-cover method without compaction effort for backfill material. Earth pressures acting on the tunnel lining and displacements of the lining itself were measured with the backfill being progressed. As a result of the test, it was founded that a narrower backfill-space produced a smaller earth pressure to the tunnel wall and then resulted in the increase of tunnel lining deformation.

INTRODUCTION

The cut-and-cover tunnel method, in which the tunnel lining will be constructed in the excavated trench and covered to the original ground surface, is applied to the subway tunnel, cable tunnel, underground pathway, waterway tunnel etc. Especially for shallow tunnels such as the entrance of the excavated tunnel and the subway tunnel in urban area, cut-and-cover tunneling method is often more economical and safe than the underground tunneling method such as NATM. Nowadays it is often recommended to solve effectively the problems which are derived from environmental, biological, and other reasons. In the cut-and-cover tunneling method, the backfilled soils act to the tunnel lining wall not only as a dead load in the initial construction stage but also as a reaction body against the horizontal passive movement after the crown of the lining will be covered (Kovari et al., 1982). The structural behavior of the cut-and-cover tunnel with arch-shaped slender lining depends not only on the soil-lining interaction but also on the effect of the wall friction on the earth pressure on it (Getzler et al., 1968; Handy, 1985; Kingsley et al., 1989; Kellog, 1993). But their simultaneous effects on the behavior of the tunnel were rarely investigated (Yoo, 1997). Most of the researches concentrate only on the effects by one of them.

This content is only available via PDF.
You can access this article if you purchase or spend a download.