1.前言 日本八户市3、4、11街道隧道,是根据城市规划联结市中心与渔港地区主要干线而新开的城市公路隧道。内设双车道,由于行人多、自行车流量大,两侧又设置了人行道。隧道位于低矮的丘陵高地之下,覆盖层仅6m,开挖断面达152m~2(净空断面86.2m~2)。隧道上方地表民房密集,尤其是两洞口处在陡峻的崩坍性危险区内,施工条件十分严峻。为此,必须把 1. Introduction Hachinohe City, Japan 3, 4, 11 street tunnel, is based on urban planning and municipalities and fishing ports to connect the main artery of the newly opened urban road tunnel. Built-in two-lane, due to the large number of pedestrians, bicycle traffic, and set up sidewalks on both sides. The tunnel is located below the low hills and highlands with a cover of only 6m and an excavated section of 152m ~ 2 (86.2m ~ 2 clearance section). The surface of the tunnel above the densely populated houses, especially the two openings in the steep collapse danger zone, the construction conditions are very serious. To this end, we must put