無砂管管材進出

首先(xian)鋼(gang)筋混凝(ning)土頂管(guan)小(xiao)覆(fu)土：一(yi)般要求管(guan)頂覆(fu)土大于2.5倍的(de)管道(dao)外直徑(jing)，其小不得小于1.5倍(bei)的(de)(de)(de)(de)管(guan)道外直徑。 其(qi)次 鋼筋混凝土頂管(guan)施工(gong)需防止地面的(de)(de)(de)(de)沉(chen)降(jiang)或隆起：在頂管(guan)施工(gong)沿線按(an)一定間距布設沉(chen)降(jiang)觀測(ce)點，監測(ce)頂管(guan)頂進施工(gong)期間的(de)(de)(de)(de)地面沉(chen)降(jiang)量(liang)。開挖端(duan)面的(de)(de)(de)(de)取土過(guo)(guo)多或過(guo)(guo)少，會造成地面的(de)(de)(de)(de)沉(chen)降(jiang)或隆起。為避(bi)免這種影響，可采取以(yi)下措施：在壓漿(jiang)時要(yao)控(kong)制好(hao)(hao)壓力，恰好(hao)(hao)能平衡“泥(ni)漿套”以上(shang)土(tu)體(ti)的壓力。嚴格控制管(guan)道 接口的密封質(zhi)量，防止滲漏。在某些(xie)管(guan)節埋(mai)藏較(jiao)淺，離地面(mian)不足1.5米(mi)的位(wei)置(zhi)，可采用(yong)沿管線局部壓鋼板，上(shang)堆(dui)砂(sha)包加載(zai)的形式，防止管節頂進時觸變泥漿上(shang)浮使到泥漿套失效。

無砂管質量控(kong)制

在施工階段(duan)，控制的要(yao)點就是嚴格按照審批通(tong)過的“施工組(zu)織設計”和“施(shi)工(gong)方案”進(jin)行(xing)(xing)施工(gong)(gong)(gong)控制，并做好關鍵工(gong)(gong)(gong)序工(gong)(gong)(gong)程(cheng)(cheng)、隱蔽(bi)工(gong)(gong)(gong)程(cheng)(cheng)驗收(shou)，閉(bi)水試(shi)驗及(ji)涂(tu)裝施工(gong)(gong)(gong)的(de)(de)質量檢(jian)驗工(gong)(gong)(gong)作(zuo)。由于頂(ding)管(guan)(guan)(guan)(guan)工(gong)(gong)(gong)藝的(de)(de)特殊性，在(zai)施工(gong)(gong)(gong)過程(cheng)(cheng)中(zhong)(zhong)(zhong)，重點(dian)做好以下(xia)內(nei)容的(de)(de)控制；工(gong)(gong)(gong)作(zuo)井(jing)(jing)(jing)(jing)作(zuo)為頂(ding)管(guan)(guan)(guan)(guan)機的(de)(de)工(gong)(gong)(gong)作(zuo)場地(di)(di)(di)，須滿足頂(ding)管(guan)(guan)(guan)(guan)過程(cheng)(cheng)中(zhong)(zhong)(zhong)結構的(de)(de)穩定，且(qie)截面(mian)設計須滿足頂(ding)管(guan)(guan)(guan)(guan)千斤(jin)頂(ding)、后背尺寸(cun)要求。在(zai)沉井(jing)(jing)(jing)(jing)施工(gong)(gong)(gong)過程(cheng)(cheng)中(zhong)(zhong)(zhong)，重點(dian)監控沉井(jing)(jing)(jing)(jing)的(de)(de)終沉階段，尤(you)其是在(zai)地(di)(di)(di)質條件不好的(de)(de)情況(kuang)下(xia)。對(dui)施工(gong)(gong)(gong)過程(cheng)(cheng)出現(xian)的(de)(de)問題，應(ying)及(ji)時進(jin)行(xing)(xing)分析和(he)糾偏，保(bao)證沉井(jing)(jing)(jing)(jing)下(xia)沉和(he)干封底的(de)(de)質量。在(zai)頂(ding)管(guan)(guan)(guan)(guan)施工(gong)(gong)(gong)前(qian)，要作(zuo)好扎(zha)扎(zha)實實的(de)(de)技術交底和(he)交底工(gong)(gong)(gong)作(zuo)。讓所(suo)有施工(gong)(gong)(gong)人員(yuan)除了掌握頂(ding)管(guan)(guan)(guan)(guan)操作(zuo)技能和(he)注(zhu)意事項外(wai)，還應(ying)掌握處置涌水、流(liu)砂等突發事的(de)(de)方法。必須按照設定的(de)(de)管(guan)(guan)(guan)(guan)道中(zhong)(zhong)(zhong)心線與頂(ding)管(guan)(guan)(guan)(guan)工(gong)(gong)(gong)作(zuo)井(jing)(jing)(jing)(jing)、接收(shou)井(jing)(jing)(jing)(jing)建立地(di)(di)(di)面(mian)與地(di)(di)(di)下(xia)測量控制系(xi)統(tong)。當頂(ding)管(guan)(guan)(guan)(guan)頂(ding)進(jin)長度較長時，必須保(bao)證通風機械的(de)(de)正常運轉，以確(que)保(bao)管(guan)(guan)(guan)(guan)內(nei)通風良好，避免。接口(kou)頂(ding)合時，應(ying)保(bao)證平(ping)整對(dui)中(zhong)(zhong)(zhong)頂(ding)入，橡膠止水圈應(ying)均(jun)勻擠壓到位，接口(kou)鋼套環或承插口(kou)管(guan)(guan)(guan)(guan)壁密貼(tie)，木墊板無松動脫落(luo)，接口(kou)間隙均(jun)勻一致(zhi)。頂(ding)管(guan)(guan)(guan)(guan)出洞(dong)前(qian)，必須進(jin)行(xing)(xing)以下(xia)的(de)(de)控制，確(que)保(bao)頂(ding)管(guan)(guan)(guan)(guan)順利出洞(dong)。A對頂管整個(ge)系統(tong)的安裝，單機調(diao)試進(jin)行檢查，并進(jin)行設備聯運(yun)調(diao)試。B檢(jian)查(cha)洞(dong)口(kou)(kou)橡(xiang)膠止水(shui)圈(quan)的安(an)裝是否牢(lao)固，尺寸是否準確，是否能完全封(feng)堵機頭(tou)與洞(dong)口(kou)(kou)空隙。C檢查洞(dong)口前方(fang)的土體是否(fou)正采取了加固措施(shi)，洞(dong)口前方(fang)是否(fou)建立了沉降監測。機頭出(chu)洞(dong)時，頂進操(cao)作應謹慎平(ping)穩勻速推進，首節管出(chu)洞(dong)口后應立即開始(shi)均勻壓注觸變泥漿。在(zai)管節出(chu)洞(dong)10～20m范圍(wei)內，檢查并督促施工員將切土、出(chu)泥、頂速、土壓、軸線、標高等(deng)施工參數逐漸(jian)調整(zheng)至正常(chang)狀(zhuang)態。