Izindlela Zokukala Umswakama Womhlabathi

Ngenhloso Yokuhlela Ukunisela

©Louise Brodie
Tensiometer dial.
Kubalulekile ukwazi isimo somswakama somhlabathi ukuze umlimi anganisela isitshalo ngesikhathi esifanele ukuqinisekisa ukuthi kukhona umswakama odingekayo emhlabathini ukuze izimpande zitshalo zisuke.
Ukulinganisa inhlabathi nokuqinisekisa ukuthi isivuno asibheki ukucindezeleka okungadingekile nokulahlekelwa kwemikhiqizo ngenxa yokungabi khona kwamanzi okutholakala enhlabathini ukukhula okusimeme kwezitshalo, izindlela ezahlukene kanye nezinsimbi zisetshenziswa ukuqapha inhlabathi kanye nokujwayelekile okusetshenziselwa ukunisela Izinhloso zokuhlela yizi:
I-Neutron Probe Meter
I-Gypsum block
I-Tensiometer noma i-irrometer
Zizwa futhi indlela yokubukeka
I-Time Domain Reflectometry (TDR) Probe

I-Neutron Probe Meter

I-Neutron Probe Meter yenza inhlabathi umswakama ngokusabalalisa i-neutron enhlabathini eyungezile. Insimbi iqukethe iphenyo ekugcineni kwekhebula eliholela ebhokisini lemitha. Le probe iqukethe umthombo we-neutron okusheshayo, okungaba yinhlanganisela ye-radium ne-beryllium noma i-Americium ne-beryllium.

I-aluminium ukufinyelela amashubhu ka-500 mm kuya ku-1 000 mm ubude futhi ububanzi buka-32 mm ububanzi bubekwa ensimini lapho kuzothathwa khona ukufundwa komswakama. Ngezimpande ezingenalutho kanye nezikhathi, ama-tubes amancane angasetshenziswa kunalawo asetshenziselwa izitshalo ezijulile ezigxile noma ezihlala isikhathi eside.

Iphenyo ye-neutron iyancipha ngaphakathi kwe-tube yokufinyelela kuya ejulile edingekayo kanye ne-neutron esheshayo ikhishwa ku-probe. Ama-neutron ayesehlakazeka emhlabathini. Lapho lezi zithwathwa zihlangana ne-athomu ye-hydrogen, ijubane le-neutron liyancishiswa futhi isilinganiso semitha siyalinganisa inani le-neutron elincane. Inani le-neutron elinciphile lilingana namakhemikhali amanzi emhlabathini ozungezile. Ngokufaka lolu lwazi kwisofthiwe okuqukethwe komswakama kwenhlabathi kuyaziwa kusukela kwendwangu yokulinganisa okubonisa ukuthi izibalo ze-neutron ezithambile.
Izinzuzo
Izindlela ziyashesha futhi ziqhubekayo. Ukusebenzisa i-Neutron probe akudingi ukuba inhlabathi iphazamiseke futhi ingakala indawo enkulu (200 mm kuya ku-400 mm ezungeze amashubhu we-probe) kunezinye izindlela.
Izindleko
Ukusebenzisa i-Probe ye-Neutron kuyabiza, isebenzisa umthombo omsakazo futhi udinga ukugcinwa njalo ngabasebenzi abakhethekile. Ukufunda okunembile kokuqukethwe komswakama kusuka emhlabathini ongajulile kuyinkinga ngoba i-neutron esheshayo ingancipha ngamanye ama-athomu e-hydrogen ezidalwa eziphilayo kanye nama-athomu okulandelwayo okuvamile okukhona emhlabathini ophezulu we-200 mm. Lokhu kubangela ukucubungula kokuqukethwe kwenhlab

I-Gypsum, i-Clay noma i-Plaster yeParis Blocks

Lezi zingxenye zokuvimbela ama-rectangular noma amabhuloki cishe angaba ngu-550 mm ubude, 375 mm ububanzi no-20 mm ubukhulu. I-Gypsum, ubumba noma i-plaster yamabhuloki aseParis asetshenziselwa ukulinganisa umswakama wenhlabathi ngokubeka amabhlogo endaweni ngqo emhlabathini okudingeka ukuba kulinganiswe futhi kuhlolwe. I-pair of electrodes yakhiwe ngamamitha angu-20 emabhuloki.
Le ndlela yokulinganisa isebenza ekuqhubeni ugesi. Uma umbane kagesi udluliselwa phakathi kwama-electrode amabili ukumelana nokugeleza kukagesi kufana nokuqukethwe komswakama ebhodini. Uma ibhulogi limanzi, ukuqhutshwa kwekhono kuphakeme futhi ngakho-ke ukumelana kuphansi. Ngokuvamile, ama-electrode afunde cishe ukuma okungamakhulu angu-400 kuya ku-600 ohms emkhakheni wamandla futhi cishe ama-50 000 endaweni ephikisayo, lapho lapho isitshalo singasakwazi ukudweba amanzi adingekayo enhlabathini ukuze azinakekele. Ukufundwa kuthathwa ngesibhuloho samanzi iWheatstone Bridge eBycos ngamaseli owomile.
Faka i-block gypsum enhlabathini engaphazamiseki.
Izindleko
Amabhlogo we-gypsum ayethembekile kakhulu enhlabathini emanzi.

I-Tensiometer/I-Irrometer

©Louise Brodie
Entire Tensiometer.
I-tensiometer iyithuluzi elilinganisa ukungezwani lapho amanzi agcinwe khona enhlabathini. Iqukethe, esitsheni sayo, indebe ye-porous ensimbi engu-8 cm noma ubumba obunamathele ensimbi yesikhumba esivimbayo noma yeglasi ephethe i-gauge ye-vacuum phezulu. Isistimu igcwele amanzi kusukela ekuvukeni phezulu kwebhubhisi futhi izogcwalisa isifuba sobumba esibucayi. I-ke ikhiqizwa yi-gauge ye-vacuum uma ihlelwa enhlabathini.
Faka i-tensiometer ngokufaka umgodi obanzi kakhulu futhi ujulile ngokwanele ukuze uvumelane ne-tube endaweni egcweleyo yesitshalo. Akufanele kube khona izikhala zomoya ezizungeze leli phuzu noma ithubhu. Kumele kube ukulingana okuqinile. Umswakama ovela ekomishini uzokhishwa ngokumiswa kwenhlabathi ezungezile. Lokhu kudala umfutho ngaphakathi kwiphubhu elilinganiselwe yi-gauge. Lapho ukufiphazwa okufunayo kufinyelelwa, inhlabathi kumele ivinjiswe. I-gauge ye-vacuum ibonisa ukulingana kwamanani kuze kube semkhathini owodwa kodwa ifundela kuphela kufika ku-0.85 emoyeni.
Izinzuzo
I-tensiometer ilula futhi kulula ukuyifaka nokufunda umswakama wenhlabathi in situ. Kuwusizo ekuhleleni ukuchelela kwezitshalo ezidinga izicelo ezivame ukungezwani kwenhlabathi ephansi.
Izindleko
Ukuzwela kwe-tensiometer kufike ku-0.85 atmospheres kuphela ngenkathi inhlabathi yomswakama etholakalayo isendaweni eyodwa. I-tensiometer nayo inembile kunomhlabathi onesihlabathi kunomhlabathi obunzima obunzima.

Indlela Yokuzwa Nokubona

Uma kungekho zindlela ezibalwe ngenhla ezitholakala, lokhu kulinganiseka kokuqukethwe komswakama kungasetshenziswa njengesisetshenziswa sokugcina samasampula omhlabathi asithathwe ezijulile ezifunayo. Isampula yomhlabathi ifakwe esandleni futhi ukuzwa kwayo nokubukeka kuthathwa. Ngokusebenzisa le ndlela, okuqukethwe okunembile kwenhlabathi umswakama akukwazi ukunqunywa.

Izinqubo ze-Time Domain Reflectometry (TDR)

©Louise Brodie
TDR moisture probe head.
I-TDR probes yindlela entsha esetshenziselwa ukuhlela ukuchelela. Le ndlela ilinganisa isikhathi esithathayo ukuze umshini kagesi uhambe ubude bezinduku zensimbi ezingenasici ezifakwe enhlabathini.
I-TDR probes isetshenziswa ngokujwayelekile ezindlini zokugcina izithombo futhi inembile kakhulu. Kodwa-ke, kuyindlela ebiza kakhulu yokusebenzisa ngesilinganiso esikhulu.

Translated by Nsika Khoza