一、什么是復合土工膜
土(tu)(tu)工(gong)膜(mo)以塑料薄膜(mo)作為防滲基材(cai)(cai),與無紡布(bu)復合而成的土(tu)(tu)工(gong)防滲材(cai)(cai)料,復合土(tu)(tu)工(gong)膜(mo)是(shi)(shi)用(yong)(yong)土(tu)(tu)工(gong)織物與土(tu)(tu)工(gong)膜(mo)復合而成的不(bu)透水材(cai)(cai)料,是(shi)(shi)一種常用(yong)(yong)的土(tu)(tu)工(gong)復合材(cai)(cai)料。
二、復合土工膜的施工方法
復合土(tu)工(gong)(gong)(gong)膜適用于水利(li)、化工(gong)(gong)(gong)、建筑、交通(tong)、地鐵、隧道、垃圾處理場等工(gong)(gong)(gong)程,施(shi)工(gong)(gong)(gong)時(shi)需(xu)要按照(zhao)規范的(de)施(shi)工(gong)(gong)(gong)方法進行施(shi)工(gong)(gong)(gong):
1、施工準備
(1)復合土工(gong)(gong)膜(mo)材料(liao)質量(liang)檢測:所用復合土工(gong)(gong)膜(mo)為(wei)兩布一(yi)膜(mo)復合土工(gong)(gong)膜(mo)。
(2)堤坡(po)的清(qing)理、平整場地,清(qing)除一切(qie)尖(jian)角雜物,欠(qian)坡(po)回填(tian)夯實、富坡(po)削坡(po)挖平后經監理驗收(shou)合格,為復合土工膜(mo)鋪設提供工作面。
(3)土工(gong)(gong)(gong)膜(mo)(mo)場內(nei)拼(pin)(pin)接(jie)為了施工(gong)(gong)(gong)方便,保(bao)證拼(pin)(pin)接(jie)質量(liang)(liang)(liang),復合(he)土工(gong)(gong)(gong)膜(mo)(mo)應盡量(liang)(liang)(liang)采用寬幅,減少現場拼(pin)(pin)接(jie)量(liang)(liang)(liang),施工(gong)(gong)(gong)前應根據(ju)復合(he)土工(gong)(gong)(gong)膜(mo)(mo)幅寬、現場長度需要,在單位內(nei)剪裁,并(bing)拼(pin)(pin)接(jie)成合(he)符要求尺寸(cun)的(de)塊體,卷在鋼管上,人(ren)工(gong)(gong)(gong)搬(ban)運到工(gong)(gong)(gong)作面(mian)鋪設。
2、復合土工膜的鋪設
(1)鋪(pu)(pu)設方法:復合土(tu)工膜鋪(pu)(pu)設分渠(qu)底鋪(pu)(pu)設、坡面(mian)(mian)(mian)鋪(pu)(pu)設兩個部分。渠(qu)底鋪(pu)(pu)設:沿渠(qu)道軸線(xian)方向水平滾(gun)鋪(pu)(pu)。坡面(mian)(mian)(mian)鋪(pu)(pu)設:在(zai)坡面(mian)(mian)(mian)驗收(shou)合格后,從順坡面(mian)(mian)(mian)軸線(xian)方向滾(gun)鋪(pu)(pu),與渠(qu)底的復合土(tu)工膜連接采(cai)用丁字形連接。
(2)鋪(pu)(pu)(pu)設技術(shu)要(yao)求:鋪(pu)(pu)(pu)設應(ying)在干(gan)燥和暖(nuan)天(tian)氣進行,為了(le)便(bian)于拼接,防止應(ying)力集中,復(fu)合土(tu)(tu)工(gong)膜(mo)(mo)鋪(pu)(pu)(pu)設采用波(bo)浪形松弛方(fang)式(shi),富余(yu)度約為1.5%,攤開(kai)后及時(shi)拉平(ping),拉開(kai),要(yao)求復(fu)合土(tu)(tu)工(gong)膜(mo)(mo)與坡面(mian)吻合平(ping)整,無突起褶皺,施(shi)工(gong)人員應(ying)穿平(ping)底布(bu)鞋(xie)或軟膠鞋(xie),嚴禁(jin)穿釘鞋(xie),以免踩壞土(tu)(tu)工(gong)膜(mo)(mo),施(shi)工(gong)時(shi)如(ru)發現土(tu)(tu)工(gong)膜(mo)(mo)損壞,應(ying)及時(shi)修補。
3、復合土工膜的拼接
(1)復(fu)(fu)合土工(gong)(gong)膜的(de)拼接(jie)(jie)(jie)包(bao)括土工(gong)(gong)布的(de)縫接(jie)(jie)(jie)、土工(gong)(gong)膜的(de)焊接(jie)(jie)(jie),焊接(jie)(jie)(jie)采用熱(re)熔焊法施(shi)。為(wei)了確保焊接(jie)(jie)(jie)質量,焊接(jie)(jie)(jie)應(ying)盡(jin)量在廠內進行,但為(wei)了施(shi)工(gong)(gong)方便,復(fu)(fu)合土工(gong)(gong)膜幅寬(kuan)又不應(ying)太寬(kuan),必須在施(shi)工(gong)(gong)現場拼接(jie)(jie)(jie)。
(2)復(fu)合(he)土(tu)工(gong)(gong)膜焊接(jie)質(zhi)量的(de)(de)好壞是(shi)復(fu)合(he)土(tu)工(gong)(gong)膜防滲性能成敗(bai)的(de)(de)關(guan)鍵,所以務必做好土(tu)工(gong)(gong)膜的(de)(de)焊接(jie),確(que)保焊接(jie)質(zhi)量,因此,土(tu)工(gong)(gong)膜焊接(jie)應由生產廠家派專業(ye)技術人員到現場(chang)操作,指導,培訓,采(cai)用土(tu)工(gong)(gong)膜專用焊接(jie)設備進行。
(3)焊接(jie)(jie)(jie)工藝:第(di)一幅(fu)(fu)土(tu)工膜(mo)(mo)鋪好后(hou),將(jiang)需焊接(jie)(jie)(jie)的邊翻(fan)疊(約60cm寬),第(di)二幅(fu)(fu)反(fan)向鋪在(zai)第(di)一幅(fu)(fu)膜(mo)(mo)上,調整兩幅(fu)(fu)膜(mo)(mo)焊接(jie)(jie)(jie)邊緣走向,使之(zhi)搭接(jie)(jie)(jie)10cm。
(4)焊(han)(han)(han)(han)(han)接(jie)(jie)前(qian)用(yong)電吹風吹去膜面(mian)上的砂子、泥土等臟物,保證膜面(mian)干凈,在焊(han)(han)(han)(han)(han)接(jie)(jie)部分的底下(xia)墊一(yi)條(tiao)長木板,以便焊(han)(han)(han)(han)(han)機在平整的基(ji)面(mian)上行走,保證焊(han)(han)(han)(han)(han)接(jie)(jie)質(zhi)量(liang),正式(shi)焊(han)(han)(han)(han)(han)接(jie)(jie)前(qian),根據施工氣溫進行試焊(han)(han)(han)(han)(han),確定(ding)行走速(su)度(du)(du)和施焊(han)(han)(han)(han)(han)溫度(du)(du),一(yi)般掌握行走速(su)度(du)(du)1.5~2.5m/s,施焊(han)(han)(han)(han)(han)溫度(du)(du)為220~300 0C。拼(pin)接(jie)(jie)焊(han)(han)(han)(han)(han)縫兩條(tiao),每條(tiao)寬(kuan)10mm,兩條(tiao)焊(han)(han)(han)(han)(han)縫間留有10mm的空腔(qiang),用(yong)此(ci)空腔(qiang)檢查(cha)其(qi)焊(han)(han)(han)(han)(han)縫質(zhi)量(liang)。
4、復合土工膜的錨固
復合土工(gong)膜上部錨(mao)固采用在堤(di)頂處嵌固足夠長度的(de)復合土工(gong)膜。
5、墊層及砼護砌
復(fu)合(he)土工(gong)膜(mo)(mo)的(de)上(shang)面均勻鋪(pu)(pu)設10cm砂墊(dian)層,找平拍(pai)實后鋪(pu)(pu)設10cm砼(tong)。坡面復(fu)合(he)土工(gong)膜(mo)(mo)鋪(pu)(pu)設合(he)格后應及時鋪(pu)(pu)上(shang)墊(dian)層壓蓋(gai),防止風吹(chui)及復(fu)合(he)土工(gong)膜(mo)(mo)暴曬老化,同時做好砼(tong)護(hu)砌,加(jia)強復(fu)合(he)土工(gong)膜(mo)(mo)的(de)保護(hu)。
三、復合土工膜施工注意事項有哪些
1、使用(yong)須(xu)采用(yong)埋入式:覆(fu)蓋厚度不宜小于30cm。
2、整修防滲系統應有:墊層、防滲層、過渡層、保護層組成。
3、土體要堅實,避免不均勻沉陷,裂紋,防滲范圍內的草皮、樹根要清除。與土工膜接觸面應(ying)鋪(pu)設粒徑(jing)小的沙(sha)土或粘土作防(fang)護層(ceng)。
4、鋪設時土工(gong)膜不要拉得太緊,兩端埋入土體部(bu)分成波紋狀較(jiao)好,特別是與剛性材(cai)料錨固時,應(ying)留有一定的伸(shen)縮量。
5、施(shi)工時,應避免(mian)石塊,重物(wu)直接砸(za)在土(tu)工膜(mo)上,最好邊(bian)施(shi)工,邊(bian)鋪設膜(mo),邊(bian)覆蓋保護(hu)層。