市政管網簡述市政給排水工程中的頂管施工技術！

市(shi)政給排水管線施(shi)工(gong)涉(she)及(ji)的因素(su)比較(jiao)復雜,要處理好施(shi)工(gong)和各種城市(shi)生活的和諧進行,管道工(gong)程施(shi)工(gong)要做到(dao)盡量(liang)程度的減少施(shi)工(gong)對居民(min)生活、交通、工(gong)作(zuo)的影響。

一、市政給排水管線(xian)工程施工要點

施(shi)工方(fang)案對(dui)不(bu)同的管線(xian)、管質、管型(xing)和(he)不(bu)同的路段其側重點有所不(bu)同。市政管網針對(dui)不(bu)同路段,不(bu)同的地質和(he)環(huan)境情況,應該制訂不(bu)同的施(shi)工方(fang)案。市政給排水管線(xian)施(shi)工存在以下幾種情形：

（一）開挖(wa)施(shi)工(gong)。市政管道穿越(yue)市政各種建筑物,為避免不必(bi)要的麻煩,大(da)多沿路鋪設(she)。在(zai)非(fei)主(zhu)干道或路邊(bian)不大(da)影響(xiang)交通的情況下可采(cai)用(yong)明挖(wa)施(shi)工(gong)。

（二）頂(ding)管(guan)(guan)施工。市政管(guan)(guan)道在(zai)跨路施工開(kai)挖(wa)存在(zai)影(ying)響交通等各(ge)方面困難時,頂(ding)管(guan)(guan)施工是一(yi)種(zhong)可行的方案(an)選擇。頂(ding)管(guan)(guan)施工從(cong)考慮(lv)人員在(zai)管(guan)(guan)道內施工作業(ye)考慮(lv),管(guan)(guan)徑一(yi)般在(zai)0.8m以(yi)上,有(you)鋼管(guan)(guan)和(he)水泥(ni)管(guan)(guan)兩種(zhong)管(guan)(guan)型,市政排污管(guan)(guan)多用(yong)水泥(ni)管(guan)(guan),自來(lai)水和(he)煤氣管(guan)(guan)道多用(yong)鋼管(guan)(guan)。

二、頂管施工技術

頂(ding)管法施工(gong)(gong)方法經常(chang)用(yong)于城市(shi)(shi)市(shi)(shi)政管道(dao)的(de)(de)建設中,使用(yong)該方法占地面積少,施工(gong)(gong)控制嚴格,可保證(zheng)交通(tong)暢通(tong)；在穿(chuan)越鐵路、公(gong)路、河流、建筑物等障礙物時可減少沿(yan)線的(de)(de)拆遷工(gong)(gong)作(zuo)量,降低工(gong)(gong)程造價。因此,對(dui)頂(ding)管施工(gong)(gong)技術及其引(yin)起的(de)(de)環境效(xiao)應進行深入分析、探求解(jie)決對(dui)策具有(you)重要的(de)(de)實際(ji)意義。

（一）頂(ding)管施工的(de)基本原理：

頂(ding)管(guan)(guan)(guan)施(shi)工(gong)(gong)(gong)就(jiu)是借助于主頂(ding)油缸以(yi)(yi)及中繼(ji)間(jian)的(de)(de)頂(ding)進(jin)力(li)(li)(li),把(ba)工(gong)(gong)(gong)具管(guan)(guan)(guan)或頂(ding)管(guan)(guan)(guan)掘進(jin)機(ji)從工(gong)(gong)(gong)作(zuo)坑內穿過土(tu)(tu)層一(yi)(yi)直頂(ding)進(jin)到(dao)接收坑內吊起。與此(ci)同時(shi),把(ba)緊隨在(zai)工(gong)(gong)(gong)具管(guan)(guan)(guan)或掘進(jin)機(ji)后(hou)的(de)(de)管(guan)(guan)(guan)道埋設(she)在(zai)兩個工(gong)(gong)(gong)作(zuo)坑之間(jian)。在(zai)頂(ding)管(guan)(guan)(guan)施(shi)工(gong)(gong)(gong)中主要有(you)(you)三種(zhong)工(gong)(gong)(gong)作(zuo)面平(ping)(ping)衡(heng)(heng)理論：氣壓(ya)(ya)、土(tu)(tu)壓(ya)(ya)和(he)泥(ni)(ni)(ni)水(shui)(shui)(shui)平(ping)(ping)衡(heng)(heng)理論。本文(wen)主要介紹(shao)泥(ni)(ni)(ni)水(shui)(shui)(shui)平(ping)(ping)衡(heng)(heng)頂(ding)管(guan)(guan)(guan)工(gong)(gong)(gong)法。泥(ni)(ni)(ni)水(shui)(shui)(shui)平(ping)(ping)衡(heng)(heng)頂(ding)管(guan)(guan)(guan)的(de)(de)工(gong)(gong)(gong)作(zuo)原(yuan)理：通(tong)常把(ba)用(yong)水(shui)(shui)(shui)力(li)(li)(li)切削(xue)(xue)泥(ni)(ni)(ni)土(tu)(tu),采用(yong)機(ji)械切削(xue)(xue)泥(ni)(ni)(ni)土(tu)(tu)而采用(yong)水(shui)(shui)(shui)力(li)(li)(li)輸(shu)送(song)棄(qi)土(tu)(tu),同時(shi)有(you)(you)的(de)(de)利(li)用(yong)泥(ni)(ni)(ni)水(shui)(shui)(shui)壓(ya)(ya)力(li)(li)(li)來平(ping)(ping)衡(heng)(heng)地(di)下水(shui)(shui)(shui)壓(ya)(ya)力(li)(li)(li)和(he)土(tu)(tu)壓(ya)(ya)力(li)(li)(li)的(de)(de)這(zhe)(zhe)一(yi)(yi)類頂(ding)管(guan)(guan)(guan)形式(shi)都稱為(wei)泥(ni)(ni)(ni)水(shui)(shui)(shui)平(ping)(ping)衡(heng)(heng)頂(ding)管(guan)(guan)(guan)施(shi)工(gong)(gong)(gong)。在(zai)泥(ni)(ni)(ni)水(shui)(shui)(shui)平(ping)(ping)衡(heng)(heng)頂(ding)管(guan)(guan)(guan)施(shi)工(gong)(gong)(gong)中,要使挖掘面上保(bao)持穩定(ding)(ding),就(jiu)必須在(zai)泥(ni)(ni)(ni)水(shui)(shui)(shui)倉中充滿一(yi)(yi)定(ding)(ding)壓(ya)(ya)力(li)(li)(li)的(de)(de)泥(ni)(ni)(ni)水(shui)(shui)(shui),泥(ni)(ni)(ni)水(shui)(shui)(shui)在(zai)挖掘面上可(ke)以(yi)(yi)形成(cheng)一(yi)(yi)層不透(tou)水(shui)(shui)(shui)的(de)(de)泥(ni)(ni)(ni)膜(mo),以(yi)(yi)阻止泥(ni)(ni)(ni)水(shui)(shui)(shui)向挖掘面里滲透(tou)。同時(shi),該泥(ni)(ni)(ni)水(shui)(shui)(shui)本身又有(you)(you)一(yi)(yi)定(ding)(ding)的(de)(de)壓(ya)(ya)力(li)(li)(li),因(yin)此(ci)它就(jiu)可(ke)以(yi)(yi)用(yong)來平(ping)(ping)衡(heng)(heng)地(di)下水(shui)(shui)(shui)壓(ya)(ya)力(li)(li)(li)和(he)土(tu)(tu)壓(ya)(ya)力(li)(li)(li),這(zhe)(zhe)就(jiu)是泥(ni)(ni)(ni)水(shui)(shui)(shui)平(ping)(ping)衡(heng)(heng)頂(ding)管(guan)(guan)(guan)最基本的(de)(de)原(yuan)理。

（二）頂管掘進機。

頂(ding)(ding)管(guan)(guan)(guan)機(ji)的(de)刀(dao)(dao)(dao)(dao)盤(pan)(pan)前面(mian)(mian)切(qie)割(ge)面(mian)(mian)安裝有合金(jin)滾(gun)(gun)(gun)動(dong)(dong)(dong)(dong)滾(gun)(gun)(gun)刀(dao)(dao)(dao)(dao)及(ji)固定刮(gua)刀(dao)(dao)(dao)(dao),刀(dao)(dao)(dao)(dao)座和(he)(he)刀(dao)(dao)(dao)(dao)盤(pan)(pan)焊接采用耐磨焊條。市政管(guan)(guan)(guan)網滾(gun)(gun)(gun)刀(dao)(dao)(dao)(dao)及(ji)刮(gua)刀(dao)(dao)(dao)(dao)在刀(dao)(dao)(dao)(dao)盤(pan)(pan)的(de)4把刀(dao)(dao)(dao)(dao)桿上的(de)布置是全段面(mian)(mian)切(qie)割(ge)布置,刀(dao)(dao)(dao)(dao)盤(pan)(pan)每轉動(dong)(dong)(dong)(dong)一周,滾(gun)(gun)(gun)刀(dao)(dao)(dao)(dao)和(he)(he)刮(gua)刀(dao)(dao)(dao)(dao)對前面(mian)(mian)土(tu)(tu)(tu)(tu)體(ti)(ti)是全段面(mian)(mian)的(de)滾(gun)(gun)(gun)動(dong)(dong)(dong)(dong)和(he)(he)刮(gua)動(dong)(dong)(dong)(dong)。頂(ding)(ding)管(guan)(guan)(guan)機(ji)在主頂(ding)(ding)裝置的(de)推動(dong)(dong)(dong)(dong)下(xia),刀(dao)(dao)(dao)(dao)盤(pan)(pan)上的(de)滾(gun)(gun)(gun)刀(dao)(dao)(dao)(dao)刀(dao)(dao)(dao)(dao)尖對前面(mian)(mian)堅(jian)硬的(de)土(tu)(tu)(tu)(tu)體(ti)(ti)進(jin)行滾(gun)(gun)(gun)動(dong)(dong)(dong)(dong)擠壓,致使堅(jian)硬的(de)土(tu)(tu)(tu)(tu)體(ti)(ti)破(po)裂；刮(gua)刀(dao)(dao)(dao)(dao)對破(po)裂的(de)土(tu)(tu)(tu)(tu)體(ti)(ti)進(jin)行切(qie)割(ge),掏(tao)空前方(fang)土(tu)(tu)(tu)(tu)體(ti)(ti),使頂(ding)(ding)管(guan)(guan)(guan)機(ji)向前推進(jin)。頂(ding)(ding)管(guan)(guan)(guan)機(ji)的(de)刀(dao)(dao)(dao)(dao)盤(pan)(pan)和(he)(he)泥(ni)土(tu)(tu)(tu)(tu)倉(cang)是個多棱體(ti)(ti),且刀(dao)(dao)(dao)(dao)盤(pan)(pan)是圍繞主軸作偏(pian)心轉動(dong)(dong)(dong)(dong),經過刀(dao)(dao)(dao)(dao)盤(pan)(pan)對前方(fang)土(tu)(tu)(tu)(tu)體(ti)(ti)切(qie)割(ge),當有大(da)塊(kuai)土(tu)(tu)(tu)(tu)體(ti)(ti)或塊(kuai)石進(jin)入頂(ding)(ding)管(guan)(guan)(guan)機(ji)泥(ni)土(tu)(tu)(tu)(tu)倉(cang),經刀(dao)(dao)(dao)(dao)盤(pan)(pan)轉動(dong)(dong)(dong)(dong)時就會被軋碎(sui),碎(sui)塊(kuai)泥(ni)土(tu)(tu)(tu)(tu)小于頂(ding)(ding)管(guan)(guan)(guan)機(ji)的(de)隔柵孔就進(jin)入泥(ni)水倉(cang)被泥(ni)水循環管(guan)(guan)(guan)輸(shu)送走。

（三）主要施工技術措施

1.泥(ni)漿(jiang)(jiang)(jiang)減阻(zu)。用(yong)(yong)(yong)泥(ni)漿(jiang)(jiang)(jiang)減阻(zu)是長距離頂管(guan)(guan)減少(shao)摩阻(zu)力(li)的(de)(de)(de)重要(yao)環(huan)節之一。在(zai)頂管(guan)(guan)施工(gong)前,先用(yong)(yong)(yong)水潤濕混凝土(tu)管(guan)(guan)材(cai),然后(hou)(hou)用(yong)(yong)(yong)黃油或機油外(wai)(wai)涂。在(zai)頂管(guan)(guan)施工(gong)過程中(zhong),如(ru)果(guo)注(zhu)入的(de)(de)(de)潤滑(hua)(hua)泥(ni)漿(jiang)(jiang)(jiang)在(zai)管(guan)(guan)子的(de)(de)(de)外(wai)(wai)圍形成一個比較完整的(de)(de)(de)漿(jiang)(jiang)(jiang)套(tao),則其(qi)減磨(mo)效果(guo)將是十分令人滿意的(de)(de)(de),補漿(jiang)(jiang)(jiang)管(guan)(guan)一般(ban)布置(zhi)(zhi)(zhi)于中(zhong)繼環(huan)后(hou)(hou)面第二(er)節管(guan)(guan)段及(ji)中(zhong)斷環(huan)與(yu)工(gong)具頭及(ji)后(hou)(hou)座中(zhong)間的(de)(de)(de)位(wei)置(zhi)(zhi)(zhi),注(zhu)漿(jiang)(jiang)(jiang)孔(kong)(kong)按120°設置(zhi)(zhi)(zhi)。頂進結束(shu),對已形成的(de)(de)(de)泥(ni)漿(jiang)(jiang)(jiang)套(tao)的(de)(de)(de)漿(jiang)(jiang)(jiang)液進行置(zhi)(zhi)(zhi)換,置(zhi)(zhi)(zhi)換漿(jiang)(jiang)(jiang)液為(wei)水泥(ni)砂(sha)漿(jiang)(jiang)(jiang)并(bing)摻入適量的(de)(de)(de)粉(fen)煤灰,在(zai)管(guan)(guan)內用(yong)(yong)(yong)單螺桿泵壓住(zhu)。壓漿(jiang)(jiang)(jiang)體凝結后(hou)(hou)(一般(ban)為(wei)24h)拆除管(guan)(guan)路換上(shang)封蓋,將孔(kong)(kong)口用(yong)(yong)(yong)環(huan)氧(yang)水泥(ni)封堵抹平。潤滑(hua)(hua)泥(ni)漿(jiang)(jiang)(jiang)用(yong)(yong)(yong)壓漿(jiang)(jiang)(jiang)泵通過總(zong)管(guan)(guan)、支(zhi)管(guan)(guan)、球閥、管(guan)(guan)節上(shang)的(de)(de)(de)預(yu)留注(zhu)漿(jiang)(jiang)(jiang)孔(kong)(kong)壓到管(guan)(guan)子與(yu)外(wai)(wai)管(guan)(guan)土(tu)體之間,包住(zhu)下班(ban)鋼(gang)夾(jia)砂(sha)管(guan)(guan)。

2.偏(pian)心破碎頂(ding)進(jin)技術。施工開始時(shi)頂(ding)進(jin)工具頭(tou)(進(jin)洞),由千斤頂(ding)頂(ding)進(jin),當(dang)頂(ding)進(jin)n節(jie)工具頭(tou)已經穿過火炬(ju)路,工具頭(tou)位(wei)置在公路邊坡擋墻下。頂(ding)進(jin)第n+1節(jie)管(guan)開始,頂(ding)進(jin)系統排(pai)漿出現碎石,有(you)堵管(guan)現象(xiang)發生(sheng),排(pai)漿泵可聽到石子與(yu)葉(xie)片撞擊聲(sheng),清理堵管(guan)管(guan)道和從泥漿沉淀池中撈碴可見碎石(花崗巖),棱角分(fen)明(ming),此(ci)時(shi)千斤頂(ding)油(you)泵油(you)壓表明(ming)顯增(zeng)大。若頂(ding)進(jin)第n+2節(jie)時(shi),排(pai)漿泵被碎石卡住,則不(bu)能正常工作。

為了防止繼(ji)續(xu)發生(sheng)碎(sui)(sui)石(shi)堵(du)(du)(du)管(guan)(guan)、堵(du)(du)(du)泵而損(sun)壞(huai)設備(bei),可制作兩個“碎(sui)(sui)石(shi)攔(lan)截箱”,分(fen)別安(an)裝(zhuang)在工(gong)具頭(tou)后和(he)排漿(jiang)(jiang)泵前,利用它攔(lan)截排漿(jiang)(jiang)管(guan)(guan)排出的(de)(de)碎(sui)(sui)石(shi),同時采用膨(peng)潤土造漿(jiang)(jiang)、循環泥漿(jiang)(jiang)出碴和(he)減緩(huan)頂(ding)(ding)(ding)速的(de)(de)方法,防止堵(du)(du)(du)管(guan)(guan)和(he)損(sun)壞(huai)設備(bei)。從頂(ding)(ding)(ding)進第n+3節開始,時有(you)堵(du)(du)(du)管(guan)(guan)、堵(du)(du)(du)泵現象發生(sheng),油泵油壓明顯增大,工(gong)具頭(tou)內(nei)的(de)(de)排漿(jiang)(jiang)管(guan)(guan)路(lu)被堵(du)(du)(du)塞,通過(guo)正反轉(zhuan)、加(jia)大泥漿(jiang)(jiang)比重、循環泥漿(jiang)(jiang)等方法,工(gong)具頭(tou)才(cai)重新啟動、工(gong)作。碎(sui)(sui)石(shi)對(dui)工(gong)具頭(tou)格(ge)(ge)柵磨損(sun)嚴重,導致(zhi)格(ge)(ge)柵脫落,必須(xu)對(dui)其(qi)維修、加(jia)固(gu)(gu)。對(dui)工(gong)具頭(tou)脫落的(de)(de)格(ge)(ge)柵重新制作安(an)裝(zhuang)后,對(dui)其(qi)余(yu)格(ge)(ge)柵進行加(jia)固(gu)(gu),由于加(jia)固(gu)(gu)后的(de)(de)格(ge)(ge)柵能夠很好(hao)地(di)解決碎(sui)(sui)石(shi)問題,保持頂(ding)(ding)(ding)力頂(ding)(ding)(ding)進,頂(ding)(ding)(ding)管(guan)(guan)施工(gong)最終順利完成施工(gong)任務。

（四(si)）為了確保該(gai)工(gong)程施工(gong),頂管作業(ye)必須(xu)做到如下幾點：

1.市政(zheng)管網核算最大頂(ding)力,設計足(zu)夠強(qiang)度和(he)穩定的后(hou)座,預先(xian)做好(hao)通過障礙物的各種可靠措施,保證開頂(ding)后(hou)連續作業(ye),以(yi)減(jian)少對列(lie)車的干擾。做好(hao)扣(kou)軌、扣(kou)梁工作。

2.管道頂(ding)入路基前(qian),如(ru)需挖(wa)去(qu)部分邊坡,只能(neng)(neng)與線路架(jia)空工作同時進(jin)行,不能(neng)(neng)提前(qian)開挖(wa)。開挖(wa)后要有防護措施,如(ru)發(fa)生路基坍塌,應及時堆碼沙(sha)包、草袋和回填。涵洞頂(ding)進(jin)到位后,立即砌筑(zhu)端翼(yi)墻及護錐,防止路基塌方。

3.頂(ding)進(jin)(jin)中嚴格控制超(chao)挖。頂(ding)管作業一般超(chao)挖不得超(chao)過(guo)30 cm,管下部135°范圍內及(ji)管底部不得超(chao)挖,以保(bao)持原狀土的路基,并按規定(ding)保(bao)持安全(quan)開挖坡度(du),防止(zhi)塌方(fang)。如發(fa)生(sheng)塌方(fang)危及(ji)列車安全(quan),應立即停止(zhi)頂(ding)進(jin)(jin),根據線(xian)路變(bian)化(hua)情(qing)況降速或(huo)封(feng)鎖(suo)線(xian)路。

4.要及(ji)時測量頂進(jin)方向及(ji)高程,隨時進(jin)行糾偏(pian)。對頂進(jin)過程中(zhong)的(de)偏(pian)差,必(bi)須及(ji)時發現并及(ji)時糾正,也是(shi)頂管成功的(de)關鍵。

三、市政給水(shui)管線(xian)工程質量監理

進一(yi)步(bu)理順質量(liang)(liang)管理體系,提高企業內部(bu)素質,引人社會監(jian)(jian)理,加強和完善政(zheng)府監(jian)(jian)督機制(zhi),加大質量(liang)(liang)監(jian)(jian)督的(de)力度；市(shi)政(zheng)管網(wang)進一(yi)步(bu)規范(fan)建設行為引人競爭機制(zhi)實行設計(ji)、施工(gong)(gong)(gong)、監(jian)(jian)理招標投標制(zhi),從制(zhi)度上(shang)保(bao)證工(gong)(gong)(gong)程(cheng)質量(liang)(liang)的(de)穩步(bu)提高；加強對工(gong)(gong)(gong)程(cheng)實施過程(cheng)中的(de)監(jian)(jian)督管理,抓住關鍵問(wen)題(ti)和重要工(gong)(gong)(gong)序,嚴(yan)格遵守設計(ji)及施工(gong)(gong)(gong)規范(fan)技術(shu)標準控制(zhi)質量(liang)(liang)問(wen)題(ti)的(de)出現。