秦岭特长隧道长达18456m,是目前我国最长的铁路隧道,设计为两座基本平行的单线隧道,线间距30m,最大埋深1600m。两线隧道纵坡基本相同,进洞后约14.7km范围内为11‰的上坡,然后以3‰的下坡出洞,长度约3.2km,隧道进口高程约870m,出口高程约1025m,线隧道较线隧道高0.24～0.56m。隧 Qinling special long tunnel up to 18456m, is the longest railway tunnel in our country, designed as two basically parallel single-lane tunnel spacing of 30m, the maximum depth of 1600m. Longitudinal slopes of the two tunnels are basically the same. After the hole is opened, the slope is about 11 ‰ in an area of ​​about 14.7km. Then a hole of 3 ‰ downhill is provided with a length of about 3.2km. The tunnel entrance elevation is about 870m and the exit elevation is about 1025m. The tunnel is 0.24 ~ 0.56m higher than the line tunnel. tunnel