A temporary arrangement in which traffic in both directions shares one tunnel tube during regular maintenance or cleansing, with the speed limit generally lowered to 50 km/h.
隧道為進行例行維修或清潔工作，安排雙向車輛使用同一條管道的臨時交通安排，車速限制一般降至每小時 50 公里。
A temporary arrangement in which traffic in both directions shares one tunnel tube during regular maintenance or cleansing, with the speed limit generally lowered to 50 km/h.
隧道為進行例行維修或清潔工作，安排雙向車輛使用同一條管道的臨時交通安排，車速限制一般降至每小時 50 公里。