An Investigation on the Influences of Construction Schemes on Backfilling the River-Crossing Section of a Utility Tunnel

Table 1

Designed backfill construction scheme of the utility tunnel.

Scheme	Below the roof	1 m above the roof
1	Unilateral backfill	Left-to-right	Case I
2			Case II
3		Middle-to-side	Case I
4			Case II
5	Bilateral backfill	Left-to-right	Case I
6			Case II
7		Middle-to-side	Case I
8			Case II