Isakhiwo somhlabathi

Ngokwakheka komhlaba kuqondwa ukuhleleka kwesigaba esiqinile emzimbeni womhlaba. Njengoba kwaziwa, umhlaba wakhiwe izinhlayiya eziqinile kanye nezikhala ezigcwele amanzi, umoya noma umusi wamanzi, ngokuvamile ingxenye umoya ingxenye amanzi. Ngokohlelo lwezinhlayiya eziqinile emhlabathini kunqunywa ukwakheka kwawo. Izakhiwo zomhlaba ongenaboshelwe nowoboshiwe zihluke kakhulu komunye nomunye.

Isakhiwo somhlabathi ongenaboshelwe

Isakhiwo somhlabathi ongaboshiwe senzeka ngaphansi kwesenzo samandla adonsela phansi. Izinhlayiya eziqinile zalo mhlabathi zinkulu futhi ziwa phansi, ziyagqama ngaphansi kwesenzo samandla adonsela phansi, kuyilapho amandla adonselanayo phakathi kwalezi zinhlayiya engekho noma emancane kakhulu futhi anqotshwa amandla adonsela phansi. Ngenxa yalokho, emhlabathini ongaboshiwe izinhlayiya eziqinile zibekwa eceleni kwenye, zigcwalise indawo yamahhala phakathi kwezinhlayiya ezibekiwe (sl. 1_a_). Uma izinhlayiya zomhlabathi ongaboshiwe zicishe zibe yindilinga futhi zilingane ngosayizi, njengoba kungaba njalo esihlabathini esinokwakheka okufanayo, khona-ke isakhiwo singaba esiminyene kakhulu (sl. 1_b_) noma esixegayo kakhulu (sl. 1_c_), kuye ngokuhleleka kwezinhlayiya eziqinile emhlabathini. Isakhiwo esiminyene kakhulu sihambisana nokuminyana okukhulu kakhulu komhlabathi ongaboshiwe kanti i-porosity yawo ingu nmin=26%. Isakhiwo esixegayo kakhulu sihambisana nokuminyana okuncane kakhulu okungenzeka komhlabathi ongaboshiwe kanti i-porosity yawo ingu nmax=48%. Ngakho-ke, isibonelo, isihlabathi esixegayo sezindunduma sine n=47%.

Ukuzinza kwezinhlayiyana zenhlabathi engaboshiwe ngaphansi kwesenzo samandla adonsela phansi

Isakhiwo esiminyene kakhulu nesingaminyene kakhulu senhlabathi engaboshiwe

Sl. 1 Ukwakheka komhlabathi ongahlanganisiwe

Uma inhlabathi engaboshwanga inobukhulu obuhlukahlukene bezinhlayiya, ukuze izinhlayiya ezincane zigcwalise izikhala phakathi kwezinkulu (sl. 2), i-porosity yenhlabathi iba ncane kakhulu (n=20% nangaphansi).

Isakhiwo senhlabathi engenabopho enobukhulu obuhlukahlukene bezinhlamvu

Sl. 2. Isakhiwo somhlabathi ongaboshiwe esinezinhlamvu zobukhulu obuhlukahlukene

Isakhiwo senhlabathi ehlanganisiwe

Enhlabathini ehlanganisiwe isakhiwo sihlukile kunasesingenakubambeka. Enhlabathini ehlanganisiwe kuvela amandla okubambisana, anamandla kunamandla adonsela phansi ezinhlayiyana ezincane futhi azinamathisele ezindaweni zokuthintana. Ngenxa yalokho lezi zinhlayiyana azilandeli ukuwa phansi ngokulandelana, kodwa zihlala zinamathele enye phezu kwenye futhi enye eduze kwenye (sl. 3_a_), ngaleyo ndlela zakhe isakhiwo esifana neketanga nenetha (sl. 3_b_), esifana nofele (sl. 3_c_) njll., okubizwa ngokuthi izakhiwo zohlelo oluphezulu. Lezi zakhiwo zinokungena komoya okukhulu, okungafinyelela ku 60-80% yesisindo sonke, okungeke kube njalo enhlabathini engenakubambeka.

Isakhiwo senhlabathi eboshiwe

Umfanekiso. 3. Isakhiwo senhlabathi ehlanganisiwe

Ubumhuzuko nokulingana kwebumhuzuko

I-porosity yenhlabathi ichazwa njengobudlelwano bevolumu yezimbobo kuya kuvolumu ephelele yenhlabathi (sl. 4).

I-porosity kanye ne-coefficient ye-porosity yomhlabathi

Sl. 4. I-porosity ne-coefficient ye-porosity yenhlabathi

Uma sikhomba ngo

  • Vp = umthamo wezigodi emhlabathini
  • Vm = umthamo wezinhlayiya eziqinile
  • V = umthamo ophelele womhlabathi,

i-porosity yomhlabathi n ngokwencazelo

n = VP / V = VP / (VP + Vm),

okungukuthi ku-% wevolumu iyonke yenhlabathi

n = 100 * VP / (VP + Vm) %.

I-coefficient yembotshana yomhlabathi ichazwa ngesilinganiso sevolumu yembobo uma iqhathaniswa nevolumu yezinhlayiya eziqinile:

e = VP / Vm.

Kusukela efomini ye-porosity n sinokuthi:

nVP + nVm = VP, lapho Vm = VP(1-n) / n.

Ngokufaka leli nani kufomula ka e sithola

e = n / (1-n).

Kulesi sibalo sithola

e - ne = n; n = e / (1 + e).

I-coefficient yokuqina kwezimbotshana ikhombisa ukuminyana kwenhlabathi. Uma i-coefficient e inkulu, nakho ukuminyana kwenhlabathi kuba kuncane, futhi ngokuphambene nalokho. Uma inhlabathi ecindezelwayo ihlala phansi ngaphansi komthwalo, ngosizo lwe-coefficient yezimbotshana ngaphambi nangemva kokuhlala phansi kunganqunywa ubukhulu bokuhlala phansi Δ_h_.

Ake sibheke ungqimba lomhlaba ohlanganekayo onogqinsi h (umz. 5_a_). Uma siwulayisha lo ungqimba, uzohlala phansi ngobude obungu Δ_h_, ukuze ugqinsi lwawo lwehle lube h1 ngenxa yomthwalo. Ngakho-ke

Δ_h_ = h – h1.

Njengoba ukuhlala komhlabathi ocomekayo kwenzeka ngenxa yama-pores, ngoba izinhlayiya eziqinile azicindezelwa cishe nhlobo, kanjalo namanzi, uma ama-pores omhlabathi egcwele wona ngokwengxenye noma ngokuphelele, lokhu kuhlala kungamelwa ngokwesikimu ku-sl. 5_b_.

Ukuhlala phansi Δh kwesendlalelo senhlabathi esicindezelayo esinobukhulu h ngaphansi komthwalo

Sl. 5. Ukuhlala Δh kwengqimba yenhlabathi ecindezelwayo enobukhulu h ngaphansi komthwalo

Uma sikhomba ngo-h0 ukuphakama okucatshangelwayo kongqimba lwezinhlayiya eziqinile ngaphandle kwama-pores, okubizwa ngokuthi ukuphakama okwehlisiwe, khona-ke singaveza ukuhlala phansi Δ_h_ maqondana nokuphakama okwehlisiwe h0 ngobudlelwano:

Ubudlelwano bokwehla Δh nokuphakama okuncishisiwe h₀

Uma sibheka ungqimba lomhlabathi olunobubanzi nobude obulingana noyedwa, khona-ke ubude h, h1 no h0 bumelela amavolumu, ngakho-ke

Ubudlelwano bezinga le-porosity ngaphambi nangemva kokuhlala

lapho e kuyinkomba yembobo ngaphambi, e1 ngemva kokuhlala phansi. Kulokhu okungenhla kutholakala ukuhlala phansi

Δ_h_ = h0 (e-e1).

Ukwehla kungavezwa maqondana nokuphakama kwesendlalelo h ngaphambi kokwehla uma sibeka inani lokuphakama okuncishisiwe h0:

h0 = h – nh = h (1-n) = h / (1+e),

njengoba n = VP / V = VP / h_,_ lapho VP = nh.

Ngakho-ke kuyatholakala

kusuka ku-3

Izinhlobo ezithile zenhlabathi zinezilinganiso ezilandelayo ezimaphakathi zeporosity n kanye ne-coefficient ye-porosity e:

Amanani ajwayelekile ombobo nokhako lokuba nezimbobo ngezinhlobo zenhlabathi

Umswakama wenhlabathi

Izinhlobo zamanzi enhlabathini

Amanzi emhlabathini avela ngendlela yamanzi ezikhaleni phakathi kwezinhlayiya eziqinile okuthiwa amanzi e-pore, bese njeng amanzi adsorbed ezinhlayiyeni eziqinile futhi njeng amanzi e-konstituciona.

Amanzi asezimbotsheni akhiwa amanzi amahhala phakathi kwezinhlayiya eziqinile, ukunyakaza kwawo kwenzeka ngokomthetho ka-Darcy, bese kuba amanzi adonswa amandla adonsela phansi, ahamba ngaphansi kwamandla adonsela phansi esuka phezulu ehle ngezindlela zonke, kodwa ukunyakaza kwawo akwenzeki ngokomthetho ka-Darcy, amanzi e-capillary ahamba ngaphansi kwamandla e-capillary kanye namanzi engcindezi ye-surface, abanjwa yingcindezi ye-surface emakhoneni phakathi kwezinhlayiya eziqinile zomhlabathi futhi abizwa nangokuthi amanzi asezimbotsheni angama-engeli. Wonke la manzi angasuswa ngokuphelele ngokomisa umhlabathi ezingeni lokushisa lika-110oC.

Amanzi adsorbed yilawo azungeza izinhlayiya eziqinile, axhunywe kuzo ngamandla ama-molecule. Lokhu okubizwa nge filimu yamanzi, ubukhulu bayo busuka ku 6-80 µµ (1µµ=10-6 mm, milimikron). Umthelela wamanzi adsorbed ezinhlayiyeni ezinkulu awubalulekile, kodwa uma izinhlayiya zincane kakhulu umthelela wawo uba mkhulu, ngoba indawo yonke yezinhlayiya iyanda futhi ngalokho kukhula nesilinganiso samanzi adsorbed maqondana nezinhlayiya eziqinile kuyunithi yevolumu yomhlabathi. Lawa manzi angasuswa kancane kuphela ngokomisa ku 110oC.

Amanzi e-konstituciona ahlangene ngokwamakhemikhali kumakristalu ezimbiwa ezizinhlayiya eziqinile zomhlabathi. Lamanzi mancane kakhulu futhi awakwazi ukukhishwa ngokomisa umhlabathi. Ngakho-ke la manzi angabhekwa njengengxenye ehlanganisayo yenhlayiya eqinile.

Inani lamanzi enhlabathini

Ngokwencazelo, inani lamanzi enhlabathini noma umswakama wenhlabathi liyisilinganiso sesisindo samanzi aqukethwe enhlabathini uma siqhathaniswa nesisindo sezinto zayo eziqinile. Ngokwenani lamanzi enhlabathini kuhlukaniswa izimo ezintathu: inhlabathi egcwele ngokuphelele ngamanzi, inhlabathi egcwele ngokwengxenye ngamanzi kanye nenhlabathi eyomile ngokuphelele.

Inhlabathi egcwele ngokuphelele ngamanzi

Uma sichaza ngo n ukubola kwenhlabathi, ngo γs isisindo somthamo wazo zonke izinhlayiyana, ngo γw isisindo somthamo wamanzi, khona-ke umswakama wenhlabathi egcwele wZ ungavezwa ngesibalo esilandelayo

Isibalo somswakama womhlaba ogcwele ngokuphelele

Umhlabathi ugcwele amanzi ngokwengxenye

Uma sikhomba ngo Ww isisindo samanzi akhona enhlabathini, ngo Wd  isisindo sezinhlayiya eziqinile noma isisindo esomile senhlabathi, khona-ke umswakama wenhlabathi w

w = Ww / Wd , noma ngamaphesenti esisindo esomile somhlabathi: w = 100 Ww / Wd.

Kulesi simo umswakama wenhlabathi ungavezwa ngesigaba somswakama Sr esimele isilinganiso sesisindo sangempela samanzi enhlabathini uma siqhathaniswa nesisindo samanzi enhlabathini efanayo obekungaba naso uma zonke izimbotshana zigcwele amanzi, noma uma kuqhathaniswa nesisindo samanzi senhlabathi egcwele ngamanzi:

Isibalo sezinga lokuswakama kwenhlabathi engagcwele ngokugcwele

ngokwez. ku-_γ_w = 1,00  Sr = w*γs / e.

Imikhawulo yokuswakama imi kanje:

  1. enhlabathini eyomile ngokuphelele w = 0; Sr = 0
  2. enhlabathini egcwele ngokuphelele w = e/γs; Sr = e/γs * γs / e = 1,0.

Isampula yomhlabathi egcwaliswe ngokwengxenye ngamanzi

Sl. 6. Isampula yomhlabathi egcwele amanzi ngokwengxenye

Izinga lokugcwala (elivame futhi ukubizwa ngokuthi ukugcwala noma izinga lokumswakama) livezwa nangobudlelwano bomthamo wama-pores agcwele amanzi uma kuqhathaniswa nomthamo ophelele wama-pores (sl. 6):

Sr = V2 / V1

lapho V2 kuyivolumu yezimbotshana ezigcwele amanzi, V1 kuyivolumu iyonke yezimbotshana ezigcwele amanzi, umoya namagesi. Uma w kungumswakama womhlabathi ngo-% wesisindo esomile somhlabathi Wd, khona-ke sinakho

V2 * γW = w Wd, lapho V2 = w Wd / γw.

Ngakolunye uhlangothi, sinakho ukuthi V1 = V – Vd, ngakho njengoba Vd * γs = Wd, khona-ke

Vd = Wd / γs futhi V1 = V – Wd / γs.

Ngakho-ke, izinga lokusuthiswa komhlabathi Sr lizoba

Isibalo sezinga lokugcwala kwenhlabathi Sr

okungukuthi ngamaphesenti esisindo esomile somhlabathi

Izinga lokugcwala komhlabathi Sr ngamaphesenti esisindo esomile somhlabathi

Umhlabathi womile ngokuphelele

Kulesi simo w = 0. Wonke amanzi asezimbotsheni asusiwe, kuyilapho amanzi anamathelisiwe esusiwe kancane kuphela, okusho ukuthi ifilimu lamanzi lisekhona, kodwa ukujiya kwalo sehlile.