Source: ngoMashi A. Torre - Izindaba ze-CE zeThe Business Of Civil Engineering
Amashubhu amakhulu agcwaliswe ngezinto ezibunjiwe asetshenziswe kumaphrojekthi ahlukahlukene asogwini nasezweni. Amashubhu, akhiqizwa amandla amakhulu we-polyester noma i-polypropylene geotextile, agcwaliswa ngogesi ngokubabazekayo, njenge-Ellicott® brand Series 370 noma i-Ellicott enkulu® uphawu ”Dragon®”Umsiki dredge. Amashubhu we-geotextile ngokuvamile agcwaliswa ngezinto ezisendaweni; noma kunjalo, ezinye izinto zingangeniswa futhi zisetshenziswe. Izicelo ezijwayelekile zizofaka phakathi: ukubuyiselwa kwesihlabathi sendunduma, ukwakhiwa kwamadike, ukwakhiwa kwezinqa, amadwala okufakelwa, nokutholakala kwemfucuza elula. Amashubhu agcwaliswa endaweni futhi ukufakwa kulula futhi akubizi.
Ukugcwalisa amashubhu we-geotextile ngezinto ezibunjiwe sekuphele iminyaka eminingi kwenziwa; kodwa-ke, ubuchwepheshe busathathwa njengobusencane. Umlando omfushane olandelayo uthathwe ngokwengxenye kusuka ku- "Geotextile Tubes-Case Histories and Lessons Learned" nguSprague, Bradley, Toups, noTrainer.
Umzamo ophindaphindiwe wokukhulisa inzuzo yamandla wokuvikelwa kwenhlabathi we-geotextiles uyabonakala emizameni yokwakha izakhiwo ze-liner kusuka kumashubhu we-geotextile agcwaliswe ngogesi. USprague ukhombise ukuthi leyo mizamo yokugcwalisa womabili amashubhu endwangu angenakugcwaliswa anesihlabathi kusukela ngonyaka we-1967. Kuyaqondakala ukuthi isihlabathi bekuyinto yokugcwalisa engakhethwa kumashubhu we-geotextile agcwaliswe ngogesi ngenxa yekhono lawo lokuzinza kalula ngaphakathi kweshubhu futhi ngokukhululeka ukukhipha amanzi, ngaleyo ndlela kwakheke isakhiwo esizinzile. Ngenxa yalokho, ngokusho kukaSprague, ukusetshenziswa okuningi okubikiwe kwamashubhu agcwaliswe ngogesi kuze kube manje kubandakanya ukufaka isihlabathi. Ukuthuthuka kwamashubhu ambalwa we-geotextile angagqanyiswa njengokubaluleke kakhulu.
Ngasekupheleni kweminyaka yama-1970, ithubhu eligcwele isihlabathi eligcwaliswe ngamanzi lisetshenziswa ngendwangu engangeneki. Uhlelo, oluthengiswe ngaphansi kwegama lokuhweba elithi "Longard Tube," lusetshenziswe ekufakweni kokuhlola okuningana.
Kusetshenziswa izinto ezibunjiwe ukugcwalisa amashubhu we-geotextile kwaqalwa ukuzanywa eBrazil naseFrance kuma-1980 okuqala. EBrazil, imigodi yokugcwalisa eqhubekayo yaakhiwa kusukela kumashubhu wokubuyiselwa komhlaba kabusha. Le ndlela yayisetshenziselwa ukwahlukanisa futhi iqukethe indawo evela endaweni eyonakele eFrance.
USprague uveze ukuthi e1989 ACZ Marine Contractors BV eNetherlands basebenzise amashubhu agcwalisiwe agcwele impahla ekwakhiweni kwezindawo ezingaphansi kwamanzi ukuqeqeshwa komfula. Besebenzisa ibhakede elenziwe ngembobo ku-crane enama-barge, ama-groins akhiwa ngokubeka isikhundla nokubeka amashubhu agcwaliswe ngaphambili. Kwakhiwa ama-groin ayishumi nanye, asebenzisa amashubhu angaphezu kwe-500.
Ukugcwaliswa okuqondile kwamashubhu we-geotextile endaweni esebenzisa ulayini wokudonsela we-dredge kuphumelele ngo-1988 eNorth Sea, ngasogwini lwaseJalimane. Ishubhu liyaqhubeka nokuhlinzeka ngokuqukethwe kokugcwaliswa ohlangothini olubheke phansi nokuvikelwa emisakazweni nasemagagasini ohlangothini lolwandle.
Beshukunyiswa i-US Army Corps of Engineers, inzalo evuselelekile kumashubhu e-geotextile yaqala ukubonakala kuma-1990s ekuqaleni lapho uhulumeni wase-US eqala ukusebenzisa ubuchwepheshe obusha. Izilingo eziningi eziphumelelayo zasebenzisa amashubhu we-geotextile agcwele isihlabathi njengama-groins futhi agcwele amasilika, ama-organic clays okwandiswa kokuqukethwe kwe-dike. Lezi zivivinyo bezanele ukukholisa onjiniyela abaningi basogwini ukuthi bacwaninge ngamathuba okusebenzisa amashubhu we-geotextile.
Kuqalisiwe
Njengoba ubuchwepheshe beshubhu le-geotextile seludonse ukunakekelwa okwengeziwe, isidingo sokwakha indinganiso yezimboni ukusungula ukwethembeka nokudonsa ukunakekelwa okuqhubekayo sagcwaliseka. Ngesikhathi sika-1999, amalungu amafemu akhiqiza ithubhu ye-geotextile ajoyine ne-Geosynthetic Research Institute (GRI) ukuthuthukisa izinga lomkhakha wezinqubo zokukhiqiza kanye nokufaka amashubhu we-geotextile. Lo mbhalo omusha we-GRI ubizwa ngokuthi "Izindlela Zokuhlola, Izakhiwo, kanye Nemvamisa Yamashubhu Amandla Aphakeme weGeotextile asetshenziswa njengezakhiwo zaseCoastal kanye neMifula." Lo mbhalo uyisilinganiso esijwayelekile sama-geotextiles asetshenziswa ekwenziweni kwamashubhu, kanye namanani wezobuchwepheshe wama-geotextiles. Futhi, izindlela zokuklama nokufaka amashubhu neziqu ezidingwa ngusonkontileka wokufaka ziyacaciswa. Yize lo mbhalo uyisiqondiso esihle sokucacisa amashubhu we-geotextile, awusizo usizo lokuklama.
Idizayini Yephrojekthi
Njengoba kukhonjisiwe nguSprague, Goodrum, noBradley, ababhali be- "Dredged Material-Filled Geotextile Tubes: Design and Construction," imiqondo yokuklama izinto ezinkulu, ezibunjiwe ezigcwalise amashubhu we-geotextile neziqukathi akubhaliwe kahle. Ngokwengeziwe, izidingo zepropathi ye-geotextile aziqondakali kahle futhi imininingwane embalwa ibikiwe ekusebenzeni kwemishini yokudonsa noma ukusebenza kwezinhlobo ezahlukahlukene zezinto ezibunjiwe. Noma kunjalo, ukufaka okususelwe kumasu okuklama "abonisiwe" kukhombisile ukuthi kuphumelele impela. Ngakho-ke, lezi zindlela ziyisiqalo sokuthuthukisa izindlela zokucwaninga ezicwaningisisiwe.
Gcwalisa ukugcinwa kanye nobuhle bokumiswa kwesibalo se-geotextile esigcwalisiwe esinikeziwe emvilophini ye-geotextile. Ukukhethwa kwendwangu kususelwa kuzo zombili izici zokuvula, okufanele zihambisane nosayizi wokugcwalisa kwezinhlayiya nokuqina, namandla, okwanele ukumelana nengcindezi yokugcwalisa. Igobolondo lendwangu eliyinhlanganisela elifaka zombili indwangu engasasebenziyo kanye nendwangu elukiwe yokuhlunga namandla, ngokulandelana, kwesinye isikhathi liyasetshenziswa.
Amashubhu we-geotextile agcwalisiwe agcwalisiwe angagcwaliswa nganoma iyiphi into ekwazi ukuhanjiswa ngogesi. Kusetshenziswe izinto ezibunjiwe ezibunjiwe nezisansimbi kuzinhlelo zokusebenza ze-dike, kepha okwenzeka ngokwemvelo olwandle noma ngesihlabathi somfula kuyisinqumo esingcono kakhulu. Umklami kufanele ahlole izici zokulungiswa kwento yokugcwalisa ukusiza ukunquma isikhala esifanele nobuningi bomjovo namachweba okusiza kuthubhu ye-geotextile.
Isigaba sesiphambano se-geotextile tube esigcwele siyisiyingi emaphethelweni bese sicabalele ngaphezulu. Okuhlangenwe nakho kwensimu kukhombisa ukuthi kungenzeka ukugcwalisa amashubhu amaphesenti angama-70 kuye kwangama-80 wobubanzi obuyindilinga obuningi bemibono, yize amaphesenti angama-50 kuye kwangama-60 enziwa kakhulu.
Ukufeza ukuzinza ngaphansi kwezimo ezinzima zokubacindezela njengokuhudula, ukuphakamisa, kanye ne-inertia, ukuthola isisindo seyunithi ephakeme kakhulu yunithi eligcwalisiwe kubalulekile. Amandla wamanje nawamaza kufanele alinganiselwe ukuhlola ukuzinza kwethumbu eligcwele le-geotextile. USprague uqaphele ukuthi yize kungakasungulwa inqubo yokuhlaziya ecacile, kuphakanyisiwe ukuthi indlela kaMiniken eguquliwe njengoba ichaziwe e-US Army Corps of Engineers; “I-Shoreline Protection Manual” inganikeza indlela enengqondo yokuhlola ukuqina kwamayunithi agcwalisiwe ngaphansi kokulayishwa kwegagasi. Ukuhlolwa kwemodeli kukhombisa ukuthi iphesenti leshubhu le-geotextile eligcwaliswe ngezinto ezibunjiwe liyipharamitha ebalulekile ephathelene nokuzinza. Okunye ukucatshangelwa okubalulekile komklamo ukuzinza kwangaphakathi kwesakhiwo seshubhu "embondelene".
Ngenxa yesenzo samanje nesamagagasi, isakhiwo esakhiwe ngoyedwa noma ngaphezulu amashubhu singashukumisa imbobo yokuqhamuka esondele ngqo kuyo, mhlawumbe okungaholela ekungazinzini kwe-geotechnical. Ngakho-ke, amadizayini kufanele afake iphrononi yendwangu yokuhlunga ukuvikela umqhele. Iphinifa lendwangu yokuhlunga, eyaziwa nangokuthi i-apron scour, imvamisa iba neshubhu elincane, elibizwa ngokuthi ishubhu lesikhonkwane, elenzelwe onqenqemeni lwasolwandle lwe-apron noma kuyo yonke indawo. Ishubhu lesikhonkwane ligcwele okokusebenza okwenziwe ngomdlandla ukusimamisa iphinifa lesikhafu. Kumele ibe nezici zokuhlunga ezifanele inhlabathi eyisisekelo kanye nenhlabathi yokugcwalisa ithubhu yesikebhe. Iphinifa le-scour kufanele linwebe ibanga elanele ngaphambi nangemuva kwesakhiwo sebhubhu le-geotextile ukuvikela isisekelo sesisekelo.
Ukufakwa kwe-Geotextile Tube 
Ukucatshangelwa okuhlukahlukene kufanele kubhekelwe ukufakwa kweshubhu le-geotextile. Iningi lalawa kufanele kubhekwane nalo ekuchazweni kwephrojekthi. Njengoba la mashubhu enziwe nge-geotextile, imihlahlandlela ejwayelekile ye-ASTM kufanele ilandelwe maqondana nokugcinwa nokuphathwa. Imihlahlandlela ye-ASTM maqondana nokwakheka kwama-geotextiles kufanele futhi ilandelwe endaweni yokubopha.
Ngaphambi kokuba amashubhu e-geotextile nama-aprons aqediwe asatshalaliswa endaweni, indawo ivame ukulungiswa kusetshenziswa imishini ejwayelekile yokuhlela. Indawo lapho kubekwa khona amashubhu we-geotextile kuvame ukumakwa ngezigaba zebanga. Izitebhisi ezinkulu noma amahange angabuye asetshenziswe ekuhlukaniseni kusengaphambili ukuze ishubhu legeotextile linamathelwe kubo ngemichilo ukuze kuqinisekiswe ukuqondaniswa okufanele ngesikhathi sokugcwalisa.
Ukuhanjiswa zombili i-apron yesikhafu ne-geotextile tube kuvame ukwenziwa ngokuzikhipha kusisekelo (noma ipayipi), kuhlinzekwa nge-tube kanye ne-apron ngumenzi. I-apron yesigcawu ihanjiswa ngaphambi kwepayipi le-geotextile, kodwa kwezinye izikhathi i-apron yesikhafu ingaxhunywa phansi kwephayiphu ye-geotextile esikhungweni sokugcwala. Lapho nje i-apron ye-scap seyisuswe ngokuphelele, yabekwa endaweni ethile, futhi yaqinisekiswa, ishubhu le-geotextile alibhalisiwe. Kufanele ibhaliswe esikhundleni somjovo kanye namachweba wokusiza abheke phezulu eceleni kwesizinda esikhulu. Lapho isisetshenzisiwe, ingavikeleka ezigxotsheni zokuvumelanisa noma amahange ngaphambili afakwe ngaphambili.
Amashubhu okusetshenzwa okusetshenziswa izindla atholakala e-ephronini lokukhwabanisa avame ukugcwaliswa kuqala ukuhlinzeka nge-ballast ye-apron yesikhwama. Ishubhu lehange kwesinye isikhathi ligcwaliswa ngemishini efanayo yokwehlisa ezosetshenziselwa ukugcwalisa ishubhu le-geotextile; kodwa-ke, ipompo elincane lingasetshenziswa njengoba amashubhu okubambelela ngokuvamile emincane (ububanzi obungamamitha amabili noma ngaphansi). Umbhobho wompompi wesikhonkwane ufinyelelwa ngokuqhekeka okulula ku-geotextile noma ngamachweba we-inlet asele enziwe.
Ngemuva kokuthi i-apron yesithonga ivikelwe ngokugcwalisa amashubhu we-anchor, ishubhu le-geotextile liyagcwaliswa. Le nqubo izothatha isikhathi eside futhi iyinkimbinkimbi kakhulu kunokumane ugcwalise amashubhu wehange. Umbhobho wokukhipha (noma umjovo wokuzalisa) we-dredge kufanele ubekwe ngaphakathi kwesiteshi esifanele somjovo we-geotextile tube. Amachweba omjovo enziwe nge-geotextile efanayo eyenza i-tube uqobo. Amachweba ajwayele ukuba ngamamitha ayi-5 (1.5 m) amayintshi angu-18 (457 mm) ububanzi, noma kunjalo, ipayipi le-dredge akufanele libe likhulu kangako; imvamisa ipayipi le-dredge dredge isetshenziselwa isisetshenziswa se-8 kuya ku-12-inch (305 mm). Ipayipi kufanele lifakwe cishe i-2 / 3 yendlela echwebeni ngomjovo futhi ivikelwe ngomshini wokuxabana. I -zzzle yomchilo kanye nembobo yomjovo futhi ivikelwe ngukudonswa kwemivimbo. Ukuxhumeka kwe-nozzle ne-injection port port kufanele kukhushulelwe endaweni ethe nkqo nge-backhoe noma nge-rigging.
Amashubhu amaningi we-geotextile azoqukatha emachwebeni amaningi okujova kulo lonke ubude bethhubhu. Amachweba ahlala atholakala endaweni ephambili endaweni eyisikhala engekho ngaphezu kwezinyawo ze-50 (15 m). Lezi zikhumulo zisetshenziselwa ukugcwalisa kanye nokusiza amanzi amaningi. Ukunqunywa kwesikhala sesibuko kufanele kwenziwe ngusonkontileka kanye / noma unjiniyela ngaphambi kokuqanjwa kwe-geotextile tube. Izici eziningana zizoba nomthelela ekuhlukaniseni kwesikhala esifanele, njengosayizi ophelele we-geotextile tube, usayizi wepayipi le-dredge, umthamo wokukhulula we-dredge, uhlobo lwento yokugcwalisa, kanye nenani lamanzi elizosetshenziswa njengemoto yokuhambisa ama-solids.
Ngokuya ngezikhala zamachweba wokujova, ukwakheka kwezinto ezibunjiwe, kanye namandla we-dredge, amanye amachweba wokujova ngeke asetshenziswe nakancane. Isibonelo, ishubhu le-geotextile le-200-foot (61 m) ubude lingaqukatha amachweba wokujova amahlanu. Uma izimo zihamba kahle futhi i-dredge inamandla, kungenzeka ukuthi yonke i-200-foot (61 m) tube ende ye-geotextile ingagcwaliswa kusuka echwebeni elilodwa lomjovo eliseduzane nomkhawulo we-tube. Imbobo yomjovo etholakala kude kakhulu izoshiywa ivulekile ukuze kuvunyelwe ukuxoshwa kwamanzi ngokweqile, kube yindawo echazayo. Onke amachweba aphakathi nendawo ayezohlanganiswa futhi ashiywe engasetshenziswa. Uma izimo zingakulungelanga ukugcwaliswa kusuka echwebeni elilodwa, khona-ke izikhathi ezinqunyelwe lapho kuthuthelwa khona ipayipi le-dredge ukuqhubeka nokugcwalisa ishubhu kufanele kunqunywe. Ukugcwaliswa kwemisebenzi kwenziwa ngokulandelana ngokusebenzisa imbobo eyodwa yokujova kanye (noma) imbobo (eyodwa) yokukhululeka. Njengoba umsebenzi uqhubeka, wonke amachweba ezingxenyeni eziphelele ze -hubhu kufanele avale ukuvimbela ukulahleka kwezinto ezivela ngaphakathi kubhahubhu.
Ngaphambi kokugcwalisa noma yikuphi okuqinile, amashubhu agcwaliswa ekuphakameni kwawo okufisayo ngamanzi kuphela. Lapho ukuphakama okudingayo sekutholakele, opharetha we-dredge bangafaka ama-solids kwi-geotextile tube. Ngokugcwalisa kuqala ishubhu ngamanzi, izinto eziqinile zivunyelwe ukusatshalaliswa ngaphakathi kwethubhu ngokulinganayo. Amamoya amasha asanda kwethulwa futhi amanzi emoto azomane akhiphe amanzi akhona.
Amaphrojekthi amaningi aqukethe amashubhu amaningi we-geotextile okumele agcwaliswe ngokulandelana okunqunyelwe kusengaphambili. Ishubhu ngalinye livame ukugcwaliswa ngokuphelele ngaphambi kokufakwa kwamashubhu alandelayo we-geotextile. Amashubhu alandelayo angabekwa aqhathaniswe neshubhu ekhona futhi agcwaliswe. Le ndlela yokufaka izokwakha indawo ephansi phakathi kwamashubhu ngenxa yemikhawulo yawo eyindilinga. Uma kungafuneki izindawo eziphansi, kungasetshenziswa ezinye izindlela zokuxhuma. Umkhuba wokufaka ovame kakhulu ukuqeda, noma okungenani ukunciphisa, inani lokudangala kungukusebenzisa ukugqagqana. Ngalolu hlobo lokuxhuma, ithubhu ngayinye elandelayo ye-geotextile (futhi imvamisa iphrononi yesikhunta) kufanele ibekwe ngaphansi komsila womhubhu obusetshenziswe phambilini. Ishubhu "elidwetshiwe" alisetshenziswanga ngokugcwele ngalesi sikhathi. Ngokusobala, le nqubo yokugqagqana kufanele ifezwe ngaphambi kokugcwalisa ithubhu ye-geotextile ngamanzi noma ngezinto eziqinile. Lapho nje ukuxhumeka sekwenziwe, ithubhu “yokuqala” ye-geotextile igcwaliswa njengoba kuchaziwe ngaphambili. Ishubhu ngayinye elandelayo nayo igcwaliswa ngendlela efanayo, noma kunjalo, isigaba sebhubhu esibekwe ngaphansi ngeke sigcwaliswe futhi ukuxhumana okuqinile (kanye "nokuphakama okugcwele") kufanele kuvele.
Lapho usuqedile ukufakwa, amachweba omjovo kufanele avikeleke kahle ukuze aqinisekise ukuthi awadabuki ngesikhathi semicimbi yamagagasi. Inqubo efanele yokuthola amachweba wokujova izonikezwa ngumakhi we-geotextile tube. Kodwa-ke, indlela ejwayele ukwenziwa ukwesula imbobo yomjovo, ngenkathi ivumela indwangu eyanele ukuba ikhiphe (noma igoqe) ifulathele ngaphezulu kwephayiphu. Indwangu egoqiwe bese iboshelwa engxenyeni ye -hubhu ngokusebenzisa amasongo wokuvimba ukumelana nokugqwala noma ukufakelwa kohlobo lokufiphaza.
Amashubhu we-geotextile agcwalisiwe futhi avaliwe azoqhubeka abe manzi futhi okukhona kuzohlanganiswa kuze kube isikhathi esithile. Isikhathi sokukhipha amanzi kanye nesikhathi sokuhlanganisa siyohluka ngokuya ngohlobo lwe-geotextile nokugcwaliswa kokuqukethwe. Imvamisa, izinto ezihlanganayo zizokhula ngokushesha okukhulu kunokwakha okufana nobumba lwesilika. Lapho inani elilindelekile lokususa amanzi selwenzekile, amashubhu we-geotextile angangcwatshwa, agcwaliswe kabusha, njll.
Isifinyezo
Yize ubuchwepheshe be-geotextile tube obugcwele dredge buye busetshenziselwa iminyaka eminingi, amaphrojekthi wakamuva aphezulu aveze imboni. Ngokusebenzisana ne-GRI ukubhala imininingwane esezingeni lomkhakha, indlela iye yathola ukuthembeka okwengeziwe. Ubuchwepheshe kanye nemboni zisencane, kepha izimiso ezintsha nezingcono ziyafinyeleleka nsuku zonke. Ngokuqinisekile ikusasa libukeka likhanyayo ngamashubhu agcwelegcwele we-geotextile.
(UGeotube® wuphawu lokuthengisa olubhalisiwe lwe-Ten Cate Nicolon)
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