** Abubuwan da ke cikin ƙwararrun ma’ajiyar kayan tarihi:** labarin yana adana bayyani na tarihi na sharuɗɗan geotechnical, dabaru da hanyoyin gwaje-gwaje. Ba binciken ilimin geotechnical ba ne, ƙirar ƙira, ƙayyadaddun ƙayyadaddun ƙayyadaddun ƙayyadaddun ƙayyadaddun ƙayyadaddun tsari, tsarin kula da inganci, ko musanyawa ga ma’auni na yanzu. Ma’aunin ƙasa, kayan aiki, ƙarfin ƙarfi, sharuɗɗan karɓa da amintattun hanyoyin aiki an ƙaddara ta injiniyan injiniya mai izini da ingantaccen dakin gwaje-gwaje dangane da takamaiman ƙasa da abu.
A yau, Savo Kusić yana mai da hankali kan gilashin katako, itace-aluminum Taga, Taga na al’ada, kofa da buƙatun magana. Wannan labarin ya ci gaba da kasancewa a matsayin tarihin fasaha kuma baya wakiltar tayin ƙirar ƙirar ƙasa, gwaji ko aiwatar da ayyukan ƙasa.
Tattarewar ƙasa maras kyau
Ƙarƙashin ƙasa maras kyau ya dogara da girman da siffar ƙaƙƙarfan barbashi, da kuma tsarinsa. A cikin yanayin ƙasa mara iyaka, akwai ƙayyadaddun iyaka waɗanda ƙimar porosity n da porosity coefficient e don ƙaƙƙarfan tsarin ƙaƙƙarfan motsi.
Idan kayan da ba a daure ya bushe kuma a zuba a hankali a cikin baƙar fata don kada ya ɗanɗana yayin zubawa, ana samun _rarest tsarinsa. Wannan tsarin ya yi daidai da ƙayyadaddun ƙayyadaddun emax, wanda ƙimar yashi a cikin rubutun asali yana cikin iyaka:
max =0,7-1,0.
Idan an zuba irin wannan abu a cikin baƙar fata a cikin siraran sirara kuma kowane Layer ana haɗa shi da mallet ɗin katako har sai ƙaramar ta tsaya tsayin daka, watau har sai ya daina daidaitawa a ƙarƙashin ƙaddamarwa, ana samun denseest structure. Ya yi daidai da emin coefficient na porosity, wanda ƙimar yashi shine:
amin =0,45-0,65.
Ƙarƙashin ƙasa mara ɗaure yana bayyana ta hanyar haɗaɗɗen dangi ID, ƙayyadaddun ƙayyadaddun ƙayyadaddun ƙayyadaddun ƙasƙanci waɗanda ke nuna matakin ƙaddamar da ƙasa dangane da mafi girman ƙaddamarwa:
inda e shine ƙaƙƙarfan porosity coefficient na ƙasa a cikin yanayin ƙaƙƙarfan yanayi. Ƙimar ƙarshe na ƙimar dangi sune:
- don tsarin da ba kasafai ba e = emax; ID =0;
- don mafi girman tsari e = emin; ID =1.
Ma’auni don tattara ƙasa mai yashi bisa ga Terzaghi a cikin rubutun asali yana karanta:
- yashi mai kauri: ID =0-1/3;
- Yashi matsakaita: ID =1/3–2/3;
- yashi mai yawa: ID =2/3-1.
A cikin yanayin ƙugiya a kan hanyoyi da shinge, rubutun yana buƙatar ID =2/3-1.
Maimakon fom ɗin da ya gabata, ana iya amfani da rabon juzu’i:
inda V shine juzu’in samfurin ƙasa wanda ba’a damu ba, Vmax shine adadin adadin ƙasa ɗaya a cikin ƙasa mafi ƙanƙanta, kuma Vmin shine juzu’in adadin ƙasa ɗaya a mafi ƙanƙantar yanayin.
Iyakar aikace-aikace: ƙila ba za a iya jujjuya rabe-raben tarihi da maganganun kai tsaye zuwa wurin aikin ko wurin gini ba. Nau’in ƙasa, hanyar samfur, yanayin samfurin, ma’auni mai dacewa da buƙatun aikin na iya canza hanya da ma’auni.
Tattarewar ƙasa mai ɗaure
A cikin ɗaure ƙanƙara ƙaddamar da ƙasa ya dogara ba kawai ga girman da siffar daskararrun da tsarinsa ba, har ma a kan haɗin kai. Saboda haɗin kai, ƙaƙƙarfan ɓangarorin suna makale tare, don haka matse ruwa daga cikin pores yayin daɗaɗɗen ya fi wuya fiye da ƙasa da ba a ɗaure ba, wanda barbashi ke motsawa cikin sauƙi a ƙarƙashin kaya.
Lokacin ƙaddamar da ƙasa mai ɗaure, adadin ruwa yana da mahimmanci. Ta hanyar tamping, ana fitar da ruwa daga cikin pores kuma kauri na fim din yana raguwa; porosity yana raguwa, kuma ƙarfin ƙarfi da yawa yana ƙaruwa. Mafi girma da yawa, da ƙarin daskararru da ƙananan pores kowace juzu’in naúrar. An karɓi wannan rabo a matsayin ginshiƙi don kimanta ƙaƙƙarfan ƙasa mai ɗaure. Ana aiwatar da sarrafa takurawa a cikin rubutu ta hanyar busassun nauyin girma:
γd = Wd / V [N/cm3]
inda Wd shine nauyin busasshen samfurin ƙasa gaba ɗaya a cikin N, kuma V shine juzu’in samfurin guda ɗaya a cikin tataccen yanayi kafin bushewa, a cikin cm3.
Gwajin Proctor
Gwajin Proctor yana aiki don tantance alakar da ke tsakanin adadin ruwan da ke cikin ƙasa da kuma taurin sa. Yana ƙayyade mafi kyawun zafi, watau yanayin zafi wanda ƙasa mai ƙanƙara ke ba da matsakaicin busasshiyar nauyin juzu’i don wani kuzarin da aka bayar.
Tarihi da aka kwatanta na’urorin Proctor (Fig1) ya ƙunshi silinda karfe tare da diamita na ciki Ø =10 cm, tsawo12 cm(hoto1_a_), ci gaban silinda mai tsayi iri ɗaya10 cm(hoto1_b_) da diamita na rammer karfe5 cm, nauyi2,5N, a cikin jagorar silinda tare da diamita mafi girma kaɗan. Jagoran yana buɗewa a ƙananan ƙarshen, kuma an rufe shi a ƙarshen babba, tare da buɗe ɗan faɗi kaɗan don hannun ragon ya wuce (hoto).1_c_ ku). Ƙarshen ƙarshen silinda an sanya shi a kan farantin karfe mafi girma kuma an gyara shi yayin tamping.
Samfurin yana bushe bisa ga tsarin asali kuma an yi shi ta hanyar sieve5 mmdon kauce wa tasirin manyan hatsi. Sa’an nan kuma a haxa shi da ruwa mai yawa wanda ba dole ba ne ya kasance mai yawa har samfurin ya zama laka, kuma ba kadan ba don ba za a iya sarrafa samfurin ba. Na farko, Layer tare da tsawo na kimanin8 cmcikin yanayin da ba’a santa ba kuma ya rame25bugun jini a ko’ina aka rarraba a saman. Ana yin tasirin ta hanyar faɗuwar mallet kyauta daga tsayi30 cm. Ana amfani da sabon Layer na kauri8 cm, zargin da sababbi25buga kuma maimaita tsari tare da Layer na uku. Bayan kammalawa, an cire tsawaitawa, saman samfurin yana daidaitawa tare da gefen ƙananan silinda, kuma an cire ƙasa mai yawa. Ana cire samfurin ƙasa mai ƙanƙara sannan a tantance busasshen yawan γd da ɗanshi w.
Hoto1- Gwajin Proctor.
An maimaita gwaninta5ku6sau, koyaushe tare da sabo, kayan da ba a kula da su ba daga samfurin iri ɗaya, amma tare da ruwa daban-daban, don samun ƙima daban-daban don γd da w. An tsara danshin ƙasa w akan abscissa na zanen, kuma an shirya nauyin busassun girma γd akan ordinate (Fig.2). Abubuwan da aka haɗa suna ba da lanƙwasa yana nuna cewa busassun busassun busassun busassun busassun busassun farko yana ƙaruwa tare da danshi zuwa matsakaicin sannan kuma yana raguwa. Yanayin zafi wopt daidai da matsakaicin busasshen girma mai girma max γd ana kiransa mafi kyawun zafi_. A cikin rubutun, an yarda da cewa a wannan zafi, ana samun mafi girman ƙaddamarwa don ƙaddamar da makamashin da aka ba. Gwajin da aka yi ta wannan hanya ana kiransa standard Proctor’s experiment.
Hoto2- Hoton Proctor.
** Tsaron Labour da Ma’auni:** Girman kayan aiki, yawan rammer da faɗuwa, adadin yadudduka da tasiri, da shirye-shiryen samfur ana watsa bayanai ta tarihi a nan, ba jagora mai zaman kanta ba. Dole ne ingantacciyar hanya ta ayyana ma’auni mai dacewa da shirin dakin gwaje-gwaje. bushewa, siffa da tamping suna ɗaukar haɗari daga ƙura, barbashi masu tashi, tsutsawa da rauni mai tasiri; Ana buƙatar kayan aiki masu dacewa, kariya da ma’aikaci mai horarwa.
Sakamakon girman hatsi ya wuce5 mm
A cikin rubutun asali an bayyana cewa hatsi masu girman gaske sun wuce5 mmba su da wani tasiri mai mahimmanci idan sun gyara25%jimlar taro. Idan akwai fiye da haka25%, Ya kamata a yi la’akari da tasirin su ta hanyar ƙididdige nauyin busassun busassun cakuda ta amfani da hanyar daidaitawa ko gwajin Proctor da aka gyara.
Lissafi ta hanyar daidaitawa
Dangane da wannan hanyar, ana ƙididdige busassun nauyin busassun kayan ƙasa na cakuda kayan ƙasa γdm bisa ma’auni na sama da ƙarƙashin girman hatsi.5 mm:
ina:
- γd - busassun nauyin nauyin kayan da ya wuce ta wurin buɗewar sieve5 mm;
- γsc - nauyin juzu’i na ƙaƙƙarfan barbashi da suka rage akan buɗewar sieve5 mm;
- m - kashi ta nauyi na kayan da suka rage akan buɗewar sieve5 mmdangane da dukan taro.
Gwajin Proctor Modified
Dangane da abubuwan da Ofishin Reclamation na Amurka ya ambata a cikin ainihin rubutu, idan hatsi ya fi girma5 mmgyara1/3ku2/3na jimlar yawan ƙasa, yakamata a yi gwajin tare da jimlar taro. Tun da ba zai yiwu a yi wannan nasara a cikin silinda na diamita ba10 cm, Ana amfani da silinda mafi girma a cikin abin da ake kira modified Proctor test. Rubutun ya bayyana silinda na diamita15,2 cmda tsawo23,2 cm, a cikin abin da samfurin yawa5,5kp ya cika kusan guda uku daidai gwargwado tare da po50ya buga da guduma mai nauyi4,53kp da sauke tsayi45,7 cm. Idan samfurin ya ƙunshi hatsi har zuwa20 mm, Ana yin gwajin tare da kayan da ba su da damuwa. Idan ya ƙunshi hatsi ya fi girma20 mm, adadin5,5kp na samfurin ana siffata ta sieve na20 mm, kuma ya maye gurbin sauran akan sieve tare da kayan girman girman5-20 mm.
Baya ga hanyar da aka bayyana ta wannan hanyar, a cikin rubutu duk wata hanyar yin aiki da ta bambanta da ma’auni kuma ana kiranta gwajin Proctor modified.
Ƙarfin ƙarfi
Za’a iya bayyana ƙarfin ƙarfin ƙarfin samfurin a cikin Silinda Proctor ta hanyar ma’auni, inda N shine adadin busa guduma, h shine tsayin digon guduma a cikin m, W shine nauyin guduma a cikin Mp (megapond), kuma V shine girman samfurin a cikin m.3.
Tare da karuwa a cikin makamashi mai ƙarfi, ana samun mafi girman ƙaddamar da samfurin, ƙarfinsa, watau adadin ruwa a cikin ƙasa, yana raguwa, kuma nauyin bushewa yana ƙaruwa. Don haɓaka makamashi E1, E2, E3kuma E4Ana samun madaidaicin ma’anar Proctor a cikin adadi3. Duk zane-zane suna farawa a asymptotically da zane mai jikewa, wanda kuma ake kira zane0%na pores na iska lokacin da dukkan pores suka cika da ruwa, watau5%na iska pores lokacin da yake95%pores cike da ruwa.
Hoto3- Zane-zane na kayan aiki don nau’ikan kuzari daban-daban.
Za a iya gina zane mai ma’ana ta hanyar yin ƙira akan abscissa w = wz = n / γs(1-n), kuma akan daidaitawa γd = γs(1-n), inda n shine porosity na ƙasa, kuma γs shine girman nauyin ƙaƙƙarfan barbashi na ƙasan da aka bayar. Yana biye da cewa za’a iya daidaita ƙarfin ƙarfin ƙarfin don samun abin da ake so. Don sarrafa ƙanƙara na ƙasa na halitta ko ƙaƙƙarfan ƙaƙƙarfan ƙaƙƙarfan, ana ɗaukar ma’anar Iz sau da yawa a cikin rubutu, rabon busassun nauyi na ƙasan da aka bayar ko embankment γd zuwa nauyin volumetric da aka samu ta hanyar Proctor γp:
Iz = γd / γp.
** Zane da sarrafawa a cikin filin: ** lanƙwan dakin gwaje-gwaje kadai ba ya tabbatar da ingancin Layer ɗin da aka samu. Samfura, kauri mai kauri, nau’in da adadin wucewar inji, zafi, ma’aunin filin, ƙarfin ɗaukar nauyi, magudanar ruwa, tsarin da ke kusa da shigarwar ƙasa dole ne a haɗa su cikin ƙira da tsarin sarrafawa. Kada ku kusanci wurin aiki na abin nadi ko wasu injuna ba tare da shirya sigina da ikon shiga ba.