Amabhuloho—Besiyokwenzenjani Ngaphandle Kwawo?

“Libonge ibhuloho owele kulo.”—George Colman, umlobi wemidlalo waseNgilandi wekhulu le-19.

WAGCINA nini ukuwela ibhuloho? Ingabe walibona lapho uwela? Izigidi zabantu ziwela amabhuloho nsuku zonke. Aseyinto nje evamile. Siwela kuwo noma sidlule ngaphansi kwawo sihamba ngezinyawo, ngamabhayisekili, noma ngezimoto, singanaki. Kodwa kwakuyoba njani ukuba ayengekho?

Sekuyizinkulungwane zeminyaka abantu nezilwane bewela ngamabhuloho anhlobonhlobo ezindaweni okungadluleki kuzo, kungakhathaliseki ukuthi yimifula, izigodi noma izihosha. Kunzima ukucabanga amanye amadolobha engenawo amabhuloho—iCairo, iLondon, iMoscow, iNew York, iSydney namanye amaningi. Yebo, amabhuloho abelokhu ekhona kusukela endulo.

Amabhuloho Asendulo

Eminyakeni engaphezu kuka-2500 edlule, iNdlovukazi uNitocris yaseBabiloni yakha ibhuloho phezu koMfula i-Ewufrathe. Ngani? Isazi-mlando esingumGreki uHerodotus siyaphendula: “[IBabiloni] lalihlukaniswe umfula laba yizifunda ezimbili. Ngaphansi kwamakhosi angaphambili, uma umuntu efuna ukuwelela kwesinye isifunda, kwakufanele awele ngesikebhe; kimina okubonakala sengathi kwakukhathaza ngempela.” Esebenzisa izingodo, izitini namatshe njengezinto zokwakha kanye nensimbi nomthofu njengokhonkolo, uNitocris wakha ibhuloho eliwela omunye wemifula yasendulo eyayidume kakhulu.

Ngezinye izikhathi amabhuloho aye athonya izenzakalo zomlando. Lapho inkosi yasePheresiya, uDariyu Omkhulu, iyohlasela abantu baseScythia, yayifuna ukusebenzisa indlela enqamulelayo esuka e-Asia iye eYurophu. Lokho kwasho ukuhola ibutho lakhe lamadoda angu-600 000 liwele iBosporus Strait. Kwakuyingozi ukuwela le nsungubezi ngesikebhe ngenxa yenkungu ekhasa phansi nemisinga eyingozi, ngakho uDariyu wabophela izikebhe ndawonye zaze zaba ibhuloho elintantayo elingamamitha angu-900 ubude. Namuhla, asikho isidingo sokuba uhlupheke njengoDariyu ukuze uwele le nsungubezi. Lolu hambo lungakuthatha imizuzu engaphansi kwemibili ngemoto uma usebenzisa amabhuloho aseBosporus e-Istanbul, eTurkey.

Uma ungumfundi weBhayibheli, ungase ukhumbule isikhathi lapho ukungabi bikho kwebhuloho kwathonya khona isenzakalo somlando. Khumbula okwenzeka lapho inkosi yaseBabiloni uNebukhadinesari ihlasela idolobha eliyisiqhingi laseTire. Yazama ukunqoba leli dolobha iminyaka engu-13, kodwa yahluleka, esinye sezizathu ukuthi kwakungenabhuloho phakathi kwalesi siqhingi nezwekazi. (Hezekeli 29:17-20) Kwathatha eminye iminyaka engamakhulu amathathu ngaphambi kokuba leli dolobha eliyisiqhingi linqotshwe, lapho u-Alexander Omkhulu akha umgwaqo onqamula emanzini osuka ezwekazini uye esiqhingini.

Ekhulwini lokuqala leminyaka, ‘zonke izindlela zaziya eRoma,’ kodwa amaRoma ayedinga amabhuloho kanye nezindlela zokuhlanganisa umbuso wawo. Besebenzisa amatshe anesisindo esingaba amathani angu-8 lilinye, onjiniyela baseRoma bakha amabhuloho amise okwekhothamo ayeklanywe ngobunyoninco kangangokuba amanye awo asekhona nakuba sekwadlula iminyaka eyizinkulungwane ezimbili. Izintuba zawo nazo zazingamabhuloho.

ENkathini Ephakathi, ngezinye izikhathi amabhuloho ayeba izinqaba. Ngo-944 C.E., amaSaxon akha ibhuloho phezu koMfula iThames eLondon ukuze avimbele ukuhlasela kwabaseDenmark. Eminyakeni engaba amakhulu amathathu kamuva, leli bhuloho lathathelwa indawo ibhuloho i-Old London Bridge, eladuma kakhulu emlandweni nasezinkondlweni.

Lapho iNdlovukazi u-Elizabeth I iqala ukubusa eNgilandi, ibhuloho i-Old London Bridge lalingaseyona nje inqaba eyakhiwe ngamatshe. Kwase kunezakhiwo phezu kwebhuloho. Kwakunezitolo esitezi sokuqala. Kuthiwani ngezitezi eziphezulu? Zaziyizindawo zokuhlala abathengisi abacebile ngisho namalungu esigodlo. ILondon Bridge yayisiyindawo abantu baseLondon ababeziphilela kuyo. Izintela ezaziqongelelwa ezitolo nasezakhiweni zokuhlala zazikhokhela izindleko zokunakekelwa kwebhuloho, kanti-ke umuntu wayekhokha lapho edlula eLondon Bridge!

Nakuba abeLungu babematasa bakha amabhuloho ngezingodo nangamatshe, ama-Inca aseNingizimu Melika ayewenza ngezindophi. Isibonelo esidumile ibhuloho laseSan Luis Rey, elalinqamula uMfula i-Apurímac ePeru. Ama-Inca ayethatha imicu yesitshalo ayiphothe ukuze enze izintambo ezinkulu ezilingana nomzimba womuntu. Abophela lezi zintambo ezinsikeni zamatshe abe esezidonsela ngaphesheya komfula. Ngemva kokubopha lezi zintambo nhlangothi zombili, ayebeka amapulangwe ukuze enze indawo yokuwela. Amaqembu abanakekeli ayevuselela lezi zintambo njalo ngemva kweminyaka emibili. Leli bhuloho lalakhiwe kahle futhi linakekelwa kahle kangangokuba lahlala iminyaka engamakhulu amahlanu!

Amabhuloho Nezidingo Zethu Ezishintshayo

Amabhuloho kumelwe akwazi ukumelana nokuzamazama komhlaba, umoya onamandla nokushintsha kwesimo sezulu. Njengoba sesibonile, onjiniyela bebesebenzisa izingodo, izitini, noma amatshe ekwakheni amabhuloho kwaze kwaba muva nje. Lapho abantu beqala ukusebenzisa izimoto ekupheleni kwekhulu le-19 leminyaka, kwadingeka ukuba amabhuloho ayekhona athuthukiswe futhi andiswe ukuze kuhambe izimoto eziningana.

Ukusungulwa kwezitimela zamalahle nakho kwakhuthaza ukwakhiwa nokuklanywa kwamabhuloho. Imizila kajantshi engcono kakhulu ngokuvamile yayinqamula ezintubeni ezibanzi noma ezigodini ezijulile. Ingabe lalingakhiwa yini ibhuloho elalingavala leso sikhala futhi lithwale izinto ezisindayo njengoba zazanda izinqola ezithwala izimpahla? Amabhuloho akhiwe ngensimbi exutshiwe asanelisa isidingo okwesikhashana. Elinye lamabhuloho adumile akhiwa ekuqaleni kwekhulu le-19 leminyaka ibhuloho elingenazinsika elinqamula iMenai Strait eNyakatho Wales, elaklanywa unjiniyela waseScotland uThomas Telford futhi laqedwa ngo-1826. Lingamamitha angu-176 ubude futhi lisasetshenziswa nanamuhla! Kodwa-ke insimbi exutshiwe yayivame ukuqhekeka, futhi ayemaningi amabhuloho ayewa. Ekugcineni, ekupheleni kwawo-1800, kwaqala ukwenziwa kwensimbi engaxutshiwe. Le nsimbi yayingasetshenziselwa ukwakha amabhuloho amade naphephile.

Izinhlobo Zamabhuloho Akhiwayo

Kunezinhlobo zamabhuloho ezingu-7 eziyisisekelo. (Bheka ibhokisi elingenhla.) Kulesi sihloko, sizothi fahla-fahla ngezimbili zazo.

Amabhuloho e-“cantilever” anemibhoshongo emibili emikhulu, nhlangothi zombili zomfula. Imishayo yensimbi ifakwa embhoshongweni ngamunye, njengoba nje kwenziwa ngebhodi lokugxumela echibini lokubhukuda. Ukuze kuqedelwe ibhuloho, le mishayo yensimbi ixhunywa phakathi nendawo ngensika eqinile.

Ezindaweni ezinomfula ogola izintethe noma ezindaweni ezithambe kakhulu, ngokuvamile kukhethwa ama-cantilever ngoba akudingeki ukuba kufakwe izinsika phakathi emfuleni. Ngenxa yokuqina kwawo, amabhuloho e-cantilever akulungele kahle ukuthwala izinto ezisindayo njengezitimela.

Mhlawumbe wake wambona umdlali esekisini ehamba phezu kwendophi. Ingabe waqaphela ukuthi eqinisweni wayewela ibhuloho—ibhuloho elingenazinsika? Amanye amabhuloho angenazinsika asetshenziswa namuhla ayafana nendophi eqinisiwe. Angase abe nentambo eboshelwe nhlangothi zombili okulengiswe kuyo ubhasikidi. Umgibeli ungena kubhasikidi abese eshwibeka aze ayofika ngalé kolunye uhlangothi. Abantu emhlabeni wonke basebenzisa amabhuloho ezintambo avamile ngaso sonke isikhathi.

Yiqiniso, ubungeke ukucabange ukuwela ngemoto ebhulohweni elenziwe ngendophi. Ngemva kokuba sekusungulwe amaketanga ensimbi namakhebula enziwe ngocingo, kwakhiwa amabhuloho angenazinsika ayengathwala izinto ezisindayo. Amabhuloho angenazinsika esimanje angase abe nomshayo wensimbi onobude obungamamitha angu-1200 noma ngaphezulu. Ngokuvamile ibhuloho elingenazinsika liba nezinsika ezimbili zensimbi, ngayinye esekele umbhoshongo. Amakhebula ensimbi, enziwe ngezinkulungwane zezingcingo, aboshelwa emibhoshongweni nasemgwaqweni ongaphansi. La makhebula yiwona ngempela athwala izimoto nomgwaqo osindayo. Uma lakhiwe kahle, ibhuloho elingenazinsika lingelinye lamabhuloho aphephe kakhulu emhlabeni.

Esikhathini esidlule, kungenzeka wawungawashayi mkhuba amabhuloho. Nokho, ngokuzayo lapho uwela ibhuloho olijwayele, zibuze: ‘Yini engiyaziyo ngaleli bhuloho? Lakhiwa nini?’ Libhekisise. Ingabe liyi-cantilever, alinazinsika, noma olunye uhlobo lwebhuloho? Kungani kwakhethwa ukuba liklanywe ngale ndlela ngokukhethekile?

Khona-ke, njengoba uwela, bheka phansi futhi uzibuze, ‘Bengiyokwenzenjani ngaphandle kwalo?’

[Ibhokisi/Isithombe ekhasini 12]

IMIKLAMO YAMABHULOHO

1. AMABHULOHO ANEMISHAYO YENSIMBI ngokuvamile akhiwa emigwaqweni emikhulu. Le mishayo ibekwe phezu kwezinsika. La mabhuloho angaba ngamamitha angu-300 ubude.

2. AMABHULOHO APHASWE NGEZINSIMBI asekelwe yizinsimbi ezinjengonxantathu. La mabhuloho, ngokuvamile asetshenziselwa uloliwe, aklanyelwe ukuba awele izigodi, imifula nezinye izithiyo.

3. EMABHULOHWENI ANEZINSIKA EZISAKHOTHAMO umshayo wensimbi ngamunye unjengekhothamo. Lolu ngolunye lwezinhlobo zamabhuloho akudala. AmaRoma ayakha amakhothamo anjalo ezintubeni futhi asebenzise itshe ukuze avale ikhothamo. Amaningi asekhona nanamuhla.

4. AMABHULOHO APHASWE NGAMAKHEBULA ENSIMBI afana namabhuloho angenazinsika kodwa amakhebula aboshelwe ngokuqondile emibhoshongweni yebhuloho.

5. AMABHULOHO ASUSWAYO angaphakanyiswa noma ajikiswe ukuze imikhumbi ikwazi ukudlula. Isibonelo esihle iTower Bridge yaseLondon.

6. AMABHULOHO E-CANTILEVER achazwe endabeni esihlokweni.

7. AMABHULOHO ANGENAZINSIKA achazwe endabeni esihlokweni.—World Book Encyclopedia, 1994.

[Ishadi ekhasini 13]

AMANYE AMABHULOHO ADUMILE

ANGENAZINSIKA

Storebaelt Denmark 1 624 m

Brooklyn U.S.A. 486 m

Golden Gate U.S.A. 1 280 m

Jiangyin Yangtze China 1 385 m

AWE-CANTILEVER

Quebec Canada 549 m

Mississippi River U.S.A. 480 m

AWEZINSIMBI EZISAKHOTHAMO

Sydney Harbour Australia 500 m

Birchenough Zimbabwe 329 m

APHASWE NGAMAKHEBULA ENSIMBI

Pont de Normandie France 856 m

Skarnsundet Norway 530 m

[Isithombe ekhasini 10]

Ibhuloho lesimanje elinemishayo yensimbi elakhiwe ngaphezu kwebhuloho elinezinsika ezisakhothamo e-Almería, eSpain

[Isithombe ekhasini 13]

IBrooklyn Bridge, eNew York, e-U.S.A. (elingenazinsika)

[Isithombe ekhasini 13]

ITower Bridge, eLondon, eNgilandi (elisuswayo)

[Isithombe ekhasini 13]

ISydney Harbour Bridge, e-Australia (elisakhothamo)

[Isithombe ekhasini 13]

ISeto Ohashi, eJapane (eliphaswe ngamakhebula ensimbi)