When there are no particular requirements on the Drawings, water flow behind the lining shall all be drained into the inner sideditch of the tunnel.
如图纸无特殊要求，衬砌背后之流水应排入隧道内侧排水沟或中央排水管内。
3
The existing highway design criterion only takes setting pavement longitudinal grade, sideditch and drainage ditch into account in order to eliminate surface water.