文章來源：中(zhong)國鐵路工程(cheng)總(zong)公(gong)司 發布時(shi)間：2008-12-04
中鐵(tie)一局2006年(nian)提出的(de)“隧道仰拱(gong)施作(zuo)距(ju)離(li)掌(zhang)子面30米(mi)，二次襯(chen)砌距(ju)離(li)仰拱(gong)30米(mi)，這兩個30米(mi)‘步長’的(de)間距(ju)控制(zhi)規(gui)范(fan)(fan)，經過長達一年(nian)多時間安(an)全(quan)均衡(heng)掘進(jin)的(de)驗(yan)證，并由(you)業主邀(yao)請國(guo)內一流專家(jia)嚴格論證，已經成(cheng)為(wei)國(guo)內大斷(duan)面黃土隧道施工的(de)新(xin)規(gui)范(fan)(fan)。
中(zhong)(zhong)鐵一局施(shi)(shi)(shi)工(gong)(gong)(gong)的(de)(de)鄭西客(ke)運專線秦(qin)東(dong)隧(sui)(sui)(sui)道(dao)(dao)全(quan)長7684米(mi)，隧(sui)(sui)(sui)道(dao)(dao)開(kai)挖斷面(mian)(mian)比國(guo)際標準排(pai)球場還大(da)(da)，是國(guo)內首座大(da)(da)斷面(mian)(mian)濕(shi)陷性(xing)黃(huang)土地(di)質隧(sui)(sui)(sui)道(dao)(dao)。濕(shi)陷性(xing)黃(huang)土承(cheng)載力非常低，遇水(shui)就要(yao)沉落。秦(qin)東(dong)隧(sui)(sui)(sui)道(dao)(dao)掘進(jin)中(zhong)(zhong)黃(huang)土含水(shui)率達到(dao)20％以上(shang)，安(an)全(quan)風險(xian)非常，隧(sui)(sui)(sui)道(dao)(dao)在(zai)施(shi)(shi)(shi)工(gong)(gong)(gong)中(zhong)(zhong)隨時可(ke)能(neng)發生變(bian)形坍(tan)(tan)塌(ta)，成(cheng)為(wei)國(guo)內外隧(sui)(sui)(sui)道(dao)(dao)施(shi)(shi)(shi)工(gong)(gong)(gong)的(de)(de)先例(li)。中(zhong)(zhong)鐵一局在(zai)秦(qin)東(dong)隧(sui)(sui)(sui)道(dao)(dao)施(shi)(shi)(shi)工(gong)(gong)(gong)中(zhong)(zhong)“及時給隧(sui)(sui)(sui)道(dao)(dao)穿上(shang)結實的(de)(de)棉襖”，用(yong)可(ke)靠的(de)(de)后部(bu)工(gong)(gong)(gong)序(xu)確(que)保前部(bu)工(gong)(gong)(gong)序(xu)的(de)(de)安(an)全(quan)推(tui)(tui)進(jin)，針對軟(ruan)弱(ruo)圍(wei)巖自穩能(neng)力極差的(de)(de)特點，二(er)次襯(chen)砌緊(jin)跟仰(yang)拱，仰(yang)拱緊(jin)跟掌(zhang)子面(mian)(mian)，用(yong)二(er)次襯(chen)砌穩固推(tui)(tui)進(jin)仰(yang)拱施(shi)(shi)(shi)工(gong)(gong)(gong)，用(yong)仰(yang)拱快速成(cheng)環穩固推(tui)(tui)進(jin)掌(zhang)子面(mian)(mian)向(xiang)前掘進(jin)，創造了“步(bu)長控制”施(shi)(shi)(shi)工(gong)(gong)(gong)理(li)論。從最(zui)后一道(dao)(dao)工(gong)(gong)(gong)序(xu)通過(guo)信息流向(xiang)上(shang)一道(dao)(dao)工(gong)(gong)(gong)序(xu)傳遞(di)信息，后部(bu)工(gong)(gong)(gong)序(xu)按時按量(liang)向(xiang)前部(bu)工(gong)(gong)(gong)序(xu)發出生產指(zhi)令。“步(bu)長控制”施(shi)(shi)(shi)工(gong)(gong)(gong)理(li)論的(de)(de)革命性(xing)意義在(zai)于徹底改變(bian)了以往(wang)隧(sui)(sui)(sui)道(dao)(dao)施(shi)(shi)(shi)工(gong)(gong)(gong)中(zhong)(zhong)前部(bu)開(kai)挖野(ye)馬長韁(jiang)，后部(bu)仰(yang)拱施(shi)(shi)(shi)作、二(er)次襯(chen)砌距(ju)離掌(zhang)子面(mian)(mian)過(guo)長，經(jing)常導致隧(sui)(sui)(sui)道(dao)(dao)失穩坍(tan)(tan)塌(ta)的(de)(de)陳舊的(de)(de)隧(sui)(sui)(sui)道(dao)(dao)施(shi)(shi)(shi)工(gong)(gong)(gong)惡習(xi)，用(yong)兩個(ge)30米(mi)嚴(yan)格的(de)(de)“步(bu)長”間距(ju)有效保證(zheng)了軟(ruan)弱(ruo)圍(wei)巖地(di)質條件下隧(sui)(sui)(sui)道(dao)(dao)的(de)(de)安(an)全(quan)施(shi)(shi)(shi)工(gong)(gong)(gong)。“步(bu)長控制”施(shi)(shi)(shi)工(gong)(gong)(gong)理(li)論把廣義的(de)(de)“新奧法概念”具體化，操(cao)作簡便，經(jing)濟效益、社(she)會(hui)效益明顯，隧(sui)(sui)(sui)道(dao)(dao)已順利(li)掘進(jin)7016米(mi)。