Nhasi, Savo Kusić inotarisa pa mahwindo emapuranga, wood-aluminium Mahwindo, mahwindo etsika, gonhi uye zvikumbiro zvekotesheni Ichi chinyorwa chinoramba chiri chegeotechnical archive uye hachisi chekupihwa chekuyedza marabhoritari, geotechnical dhizaini kana pasi.
Pane nzira dzakati wandei dzekuona zvinhu zvekuramba ivhu remukati, kubatana uye kona yekukweshana kwemukati uchishandisa bvunzo dzemurabhoritari, pakati peiyo direct shear test uye triaxial compression bvunzo ndiyo inonyanya kuzivikanwa.
Yakananga kugera ruzivo
Muedzo unoitwa pamudziyo une rectangular chikamu chemhando A. Casagrandea kana pachishandiswa denderedzwa cherudzi rwe Hvorsleva. Tichatsanangura kuedza nemudziyo wechikamu chekona, iyo ndiyo inonyanya kushandiswa. Muzviitiko zvose izvi, muedzo unoitwa nemuenzaniso usina kukanganiswa, kana nemuenzaniso wakakanganisika pane imwe nzvimbo yegoho, iyo iyo muedzo une chiyero chekuenzanisa.
Zvishandiso zvekuveura zvakananga kwechikamu cherectangular (fig. 1)
Fig. 1_Cross chikamu cheCasagrande’s direct shear apparatus_
Mudziyo une zvikamu zviviri, chepamusoro nechepazasi, apo chezasi chakamira, nepo chepamusoro chichifambiswa uye chinogona kufambiswa pane chepasi pasi pesimba reiyo horizontal force Z, iyo inoshanda panhandare yekubata kwepamusoro nepasi furemu.
Sampu yevhu inoiswa mumhete yesimbi rectangular, kazhinji yehukuru 100 × 100 × 30 mm, kana zviyero izvo kana zvakweshwa nemazvo. Sefa matombo anoiswa pamusoro nepasi pemuenzaniso, uyezve zvese zvinoiswa mumhete yemidziyo, iyo inozozadzwa nemvura. Mudziyo wekutakura wakatwasuka unoiswa pamuenzaniso. Ibwe repamusoro resefa rinosanganiswa nehurongwa hwekuisa vertical loading yemuenzaniso, asi iyo yakaderera yakabatanidzwa kune nzira dzemvura, nenzira iyo sampu inogona kuchengetwa mumamiriro ezvinhu akazara panguva yekuedzwa, kuitira kuti usabvisa kubatana kunooneka.
Kuitira kuti usasanganise kukweshana panzvimbo yekubatana pakati pepamusoro nepasi, pane midziyo ine furemu yepamusoro yakamonwa, nenzira iyo furemu yekumusoro inofamba pasi pesimba rekugera rakachinjika. Mukuwedzera, nzvimbo dzekubatana dzepamusoro nepamusoro pefuremu dzakaputirwa ne petroleum jelly. Imwe 2 muenzanisi wekunyoresa yakatwasuka uye yakachinjika deformation inosanganisirwa muchishandiso.
Kuita bvunzo dzakananga dzekugera
Pane zvakawanda2mhando dzeyedzo yakananga shear: fast uye slow bvunzo. Iyo quick bvunzo inosanganisira kurodha sampu ine imwe vertical pressure, iyo inowanzoita0,50;1,0;2,0;3,0uye4,0kp/cm2, kumirira kubatanidzwa, iyo inofungidzirwa kuti yakawanikwa kana kuderera panguva yenguva.24maawa Δh ≤0,02 mm, uye ipapo simba rekugera rakachinjika Z, rehukuru, rinoiswa1/20kana1/40chikamu chesimba rakamira P, iro rinowedzera miniti yega yega neukoshi hwakafanana kusvika pasi ratsemuka. Munguva yekushandiswa kwesimba rekuveura rakachinjika, mafambiro emufuremu wepamusoro anogara achitariswa nekuverenga pane inofananidzira uye yakachinjika deformation inonyorwa murogi pakarepo pamberi pemutoro mutsva wega wega. Iyo nguva, iyo iyo muenzanisi anoratidza kufamba kamwe kamwe, inogamuchirwa sekuputsa pasi.
Muedzo wekukurumidza unoshandiswa kune ivhu revhu, iro kubatanidzwa kwechisikigo pasi pemutoro mutsva kunononoka uye kunoenderana nenzira iyi yekuita bvunzo.
Slow bvunzo inoitwa nenzira yakafanana neyakare nemusiyano wega wekuti yakachinjika simba rekugera rinowedzera munguva yakareba, inogona kuva 2, 5 uye 15 mmaminetsi kana kusvika kubatanidzwa, i. Nzira yekubatanidza pasi pekuita kwesimba rakadzika rinotariswa pakuenzanisa 9 (fig. 1).
Muedzo unononoka unoshandiswa kune ivhu rejecha kana rine guruva, apo kana paine kuwedzera kwesimba rekugera rakachinjika munguva pfupi, kuveura kwemuenzaniso mumidziyo kuchakurumidza kukurumidza nekuda kwekuita kwemvura yakamanikidzwa mumapores, isingaenderane nemaitiro echisikigo. Nokudaro, nguva yenguva inowedzera nekunaka kwezvimedu zvevhu zvisina kuvharwa, kuitira kuti zvikwanise kuenzana kwemvura inodzvinyirira mumatope evhu nekunze kwemvura. Uku kuenzana kunowanikwa nekusiya nguva yakakwana pasi pekuita kwemwero wega wega wemutoro wakachinjika, kuitira kuti yakawandisa mvura mumapores inosvinwa kunze kuburikidza nedombo resefa.
Kuwedzera kune bvunzo dzakataurwa, mune dzimwe nguva bvunzo yekukurumidza pasina kubatanidzwa pasi peyakamira kuremerwa inoitwa, i.e. yakachinjika shear simba inoiswa pakarepo mushure mekuisa sampu mumudziyo nekuiisa nemutoro wakatwasuka. Zvisineyi, nzira iyi yekuuraya inoshandiswa pasi pemamiriro ezvinhu akakosha, akadai seyemupendero uchangobva kuiswa wakagadzirwa nevhu revhu, unotakurwa pakarepo mushure mekumisikidzwa pasina kusungirirwa.
Kutsunga kwekona yekukwesha kwemukati uye kubatana
Zvichienderana nemhedzisiro yebvunzo, iyo shear stress
τ=Z/A mu kp/cm²,
inowanikwa kubva kusimba rekugera Z mu kp panguva yekutadza uye nechikamu chechikamu chemuenzaniso A mucm². Muedzo unoitwa ne 3 kusvika 4 dhizaini yakatakura zvakasiyana siyana zvakajairika σ=P/A mu kp/cm² apo P iriyo yakatwasuka mutoro wesample mu kp. Iwo anotevera maitiro ekumanikidza akajairwa anowanzo kutorwa: 1,0; 2,0; 3,0 uye 4,0 kp/cm².
Fig. 2. Dhiagiramu yezvakachinjika deformation
Kubva padhayagiramu yezvinhu zvekukweshana kwemukati, mhando mbiri dzedhayagiramu 1 uye dhayagiramu yehorizontal deformations (fig. 2) inowanikwa.
Diagiramu yekukanganisa kwakatwasuka kunowanikwa nekushandisa iyo yakatwasuka ΔL mu mm yekumusoro furemu yechishandiso kune yakaderera pane abscissa axis, inowanikwa nekuverenga muenzanisi 9, uye pane iyo ordinate axis / ² shear inoenderana _ 2).
Zvichienderana nekutsikirirwa kwevhu, dhayagiramu 1 yeyakasungirirwa uye dhayagiramu 2 yezvakakurasika inowanikwa.
Kune chinhu chakabatanidzwa, shear stress τ inowedzera pakutanga zvakanyanya zvakanyanya maererano nekuchinjika kusimuka ΔL kusvika kumuganhu we proportionality P, uye zvishoma nezvishoma, nepo curve yedhiyagiramu.1inowedzera uye inosvika pahupamhi hwepamusoro B, mushure meiyo dhayagiramu inodzikira kune imwe urefu, kuti isvike pakuyerera kwakatwasuka. Iyo zone yekukwira-mutsetse wakatwasuka weiyo horizontal deformation dhizaini, umo kuwedzera kweshear kushushikana kwakaenzana nekuwedzera kwe deformation, inofungidzirwa kuti inzvimbo yeelastic deformation. Kupfuura muganhu P, kuwedzera kwekuveura kuderera kunoderera maererano nekuwedzera kwe deformations ΔL kusvika pakakwirira B yemufananidzo. Munharaunda iyi, zvinhu zvinotanga “kuyerera” uye zvinogamuchirwa senzvimbo yepurasitiki deformation. Nzvimbo yepamusoro yedhayagiramu B1inomiririra iyo yakanyanya shear stress max τ, uye inofungidzirwa kuti kutsemuka kwevhu kunoitika panguva ino, i.e. iyo point B ndiyo inoputsika. Beyond point B, zvinhu zviri mumvura, simba rekugera rinodzikira, uye inofungidzirwa kuti munzvimbo iyi, uko kubatana pakati pezvikamu zvakaputsika, pane chete kutsvedza kupikisa kunopesana neiyo yakatwasuka shear simba. Pongedza G pane dhayagiramu1inopfuura munzira yakachinjika inogamuchirwa semuganho wekutsvedza.
Kugera kusimba pamuganhu wekukundikana B kunodaidzwa kunzi simba rekugera kana pure shear simba τf, ukuwo kugera kusimba pamuganhu wegoho G kunonzi simba rekutsvedza τg.
Nezvezvinhu zvakasununguka, dhayagiramu yakachinjika yekuchinjisa inewo nharaunda elastic ine proportionality muganhu P, asi kudzika inzvimbo yepurasitiki inosvika painotsvedza muganhu G, i.e. iyo yakanyanya shear stress yakaenzana nemuganhu simba, kutsvedza (τ=τg), kupfuura iyo yemvura mamiriro ezvinhu.
Sl.3. Dhear diagram, a) yevhu rakabatana, b) yevhu risingawirirane
Iyo shear dhizaini inowanikwa kana yakajairika kudzvanywa σ mu kp/cm ichiiswa kune abscissa axis.2, uye paakisi yakarongeka simba rekugera rinoenderana τf mu kp/cm2, uko ese ari maviri hunhu akaiswa muchiyero chimwe (Fig.3) Sezvo simba rekugera τf yevhu richiwedzera nedzvinyiriro yakajairwa σ, zvinozoita kune dzakasiyana siyana σ1 tora mapoinzi A, B, C, uye D, ayo anomiririra anoenderana kugera simba.
Kuti uwane mapoinzi ega A, B, C uye D padhayagiramu3kune ivhu rakabatana (fig.3a), simba rekutsvedza _τ_g rinogamuchirwa. Zvisinei, kana iri ivhu revhu, zvinhu zvinotanga kuyerera nguva refu isati yasvika muganhu wekutsvedza G, uye pane tsika yekutora simba rekugera pamuganho wekuenzanisa P kuti uone kubatana c uye kona yekukwesha kwemukati kwevhu, asi sezvo ishoma, simba rekugera iro deformation ΔL inowanzotora dhizaini.2kaviri yakakura kupfuura deformation padanho rekare rekurodha mumidziyo. Iri simba riri pakati pemuganhu weP naB, kureva, G (fig.2)
Kubatanidza mapoinzi A, B, C uye D padhayagiramu 76a inopa shear diagram, inova mutsara wakatwasuka mumiedzo yakabudirira. Nekuwedzera dhayagiramu kumharadzano neakisi yakarongeka, ye σ = 0, inowanikwa zvichienderana neCoulomb pateni τf = c+σ tgϕ kuti τf = c = kubatana kwevhu, nepo kutsetseka kwedhayagiramu yakananga kune yakachinjika yemukati inopa kona. Nekuwedzera dhayagiramu yeshear kune rumwe rutivi rweakisi yakarongeka, kushushikana nekuda kwekubatana pk kunowanikwa pane abscissa axis, apo ukuru hwekubatana c hunoratidzwa seyakaenzana nekupokana:
c = pk tgϕ, kubva pk = c/tgϕ
Kune ivhu risingawirirane, sejecha, dhayagiramu yemuonde. 3b, inopfuura nepakati pemabviro akarongeka, sezvo ye σ = 0 tinowana τ = 0. Zvisinei, kana jecha rakanyatsogadzirwa uye rakanyorova, dhayagiramu yakafanana neyomuonde. 3a, ine kubatana kudiki c, inomiririra kubatana kunooneka. Pakadaro, kushushikana pk pane yakatambanudzwa abscissa axis kune rimwe divi recoordinate mavambo inomiririra capillary stress.
Inofanira kucherechedzwa kuti kutsunga kwekubatana kwevhu uye kukweshana nekukasira kuyedzwa kweshear kune zvipingamupinyi zvakati wandei, izvo zvakanyanya kukosha ndezvekuti kutadza kwevhu kunoitika pane yakatemerwa shear pamusoro uye kwete pamusoro peiyo kushoma kushora kuramba, kuti panguva yekuveura sampuli mumidziyo, iyo shear yekumusoro inoderedzwa nekuda kweiyo sampuli yekufamba kweiyo dhizaini. kugera kunogona kungotariswa kwenguva pfupi, kuitira kuti kutsvedza kwekudzivirira kudarika muganhu hakugone kudzora kuputsika kusvika pamwero wakakwana, kunyanya munyaya yevhu rakapfava kana deformations panguva yekuveura yakakura, nezvimwewo.
Triaxial compression test
Muedzo unoitwa pane triaxial apparatus, ine zvivakwa zvakasiyana, asi zvese zvakavakirwa pamusimboti mumwechete, unotevera. Sampuli isina kukanganiswa muchimiro che roller inoiswa vertically pachigadziko uye inotaridzirwa kune lateral kumanikidzwa kwemvura yakawanda kubva kumativi ose uyezve kune vertical pressure, iyo inowedzera zvishoma nezvishoma, kusvikira kuputsika kwemuenzaniso kunokonzerwa pamusoro pepamusoro pekushongedzwa kweshear. Zvichienderana nesimba rekugera panguva yekuzorora, kubatana uye kona yekukwesha kwemukati kwevhu kunoverengerwa.
Tsanangudzo yeiyo triaxial mudziyo
Fig. 4. Triaxial apparatus
Iyo triaxial apparatus (fig. 4) ine chikamu chezasi cheplate yekamuri, iyo iyo sampu inomira, uye nechepamusoro pepiston yekusimudza yakatwasuka yemuenzaniso uye ndiro yepamusoro inovhara kamuri. Zviyero zvinonyanya kuzivikanwa ndezvekuti ϕ=36 mm, kureba h=2,2-2,5_ϕ_. Kureba kwekamuri iyi D=135mm, kureba H = 180 mm. Ichubhu yakatetepa K1 yekudhonza sampuli kubva pasi inotangira kubva pakati pechigadziko chemuenzaniso, iyo inogamuchira mvura kubva mumuenzaniso kuburikidza nendiro ine porous uye inoibudisa kunze kwekamuri muchubhu yegirazi yakatwasuka C1. Kana bvunzo ikaitwa pasina kudonhedza sampuli, chiteshi ichi chinoshanda kuyera kudzvanywa kwemvura mumapores. Muchigadziko chebhuronzi chekamuri pane chiteshi K2 chekugovera huwandu hwemvura kuitira kuti uzadze mukamuri uye uwane lateral kudzvanywa mukamuri pane sampuli.
Kuburikidza neplate yepamusoro yekamuri inopfuudza mubato wepiston wekurodha sampuli. Muenzaniso uri mukamuri yakakomberedzwa nerubber membrane, iyo inotambanudzwa kumativi ose maviri uye yakabatanidzwa nepiston uye chigadziko nenzira yerubha zvindori. Pakati pepiston pane chiteshi K3 chekudhonza sampuli kubva kumusoro.
Mativi ekamuri akavharwa zvine mutsindo nePlexiglas cylinder inonamirwa kumapuleti ekumusoro neazasi ekamuri kuburikidza nemaring erabha.
Kamuri inoiswa pahwaro hwakasimba. Iyo yakajairika kurodha sampuli inoitwa kuburikidza nerevheti ine huremu, chiyero cheiyo inowanzo 1: 10. Iyo sisitimu yekuwana lateral kudzvanywa pamuenzaniso mukamuri ine bhodhoro rine mvura yakawanda B, iyo inounzwa mukamuri kuburikidza nechubhu, manometer yekuyera mhepo uye bhodhoro rine mweya wakamanikidzwa. Muenzanisi unoiswa pamusoro pepiston kuti uise sampuli kuyera kugadziriswa kwemuenzaniso pasi pemutoro.
Iyo lateral pressure yemvura yakawanda mukamuri inogona kugadziriswa pakuda uchishandisa mweya wemhepo mubhodhoro B, kuburikidza nemavharuvhu V1 uye V2. Kudzvinyirirwa uku kunokonzeresa kusagadzikana mumuenzaniso σ2 uye σ3, izvo nekuda kwechikamu chedenderedzwa chemuenzaniso zvinoenzana σ2 = σ3.
Iyo mvura yakawanda inogona kuve yakasvibiswa mvura kana mafuta, iyo inosarudzwa kuti ivhare zviri nani, nokuti mvura inogona kupfuura nepakati. Pasi pesimba rekumanikidzwa kwemhepo mubhodhoro B, iyo mvura yakawanda inozadza mukamuri kusvika kuvharuvhu V6, iyo inobva yavhara. Kuremerwa kwakatwasuka kwesample P, iyo inofambiswa zvisingaite kukweshana kumuenzaniso kuburikidza nemubato wepiston, wakakamurwa nechikamu chechikamu chemuenzaniso A inopa kusimba kwakamira σ1 = P/A
Kuita triaxial compression test
Kumuenzaniso wekuedza, inogadziriswa mune imwe yakasiyana, kuitira kuti roller ine dhayamita ye 36 mm, kureba kwe 78 mm kana 90 mm inowanikwa, painoiswa matombo efirita kubva kumusoro uye pasi uye membrane yerubha yakaiswa. Zvadaro sampuli pamwe chete nematombo ekusefa inoiswa pachigadziko mukamuri, magumo, marabhu membranes anodhonzwa pamusoro pechigadziko uye pisitoni yekurodha uye yakachengetedzwa nerabha zvindori. Zvinoenderana nemaitiro emamwe marabhoritari, akadai saProf Skempton muLondon, kudonhedza kwemuenzaniso mukamuri panguva yekuedzwa kunokurumidzirwa nekuisa mativi emuenzaniso nepepa resefa, iro rinoiswa pamberi perubber membrane yadhonzwa. Kana sampu yakaunzwa mumidziyo uye Plexiglas cylinder yakamisikidzwa mumaplateti epamusoro nepasi, zvinokwanisika kuita bvunzo, dzinogona kuitwa nenzira dzakati wandei, senge dzinotevera:
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Undrained tests. Muzviedzo izvi, kupera kwemuenzaniso hakubvumirwi panguva yekushandiswa kwe lateral uye vertical test, nepo mavhavha V4 uye V5 akavharwa.
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Miedzo isina kunyorwa ine consolidation. Munguva yekushandiswa kwe lateral pressure, sampuli inodonhedzwa (mavhavha V4 uye V5 yakazaruka), asi panguva yekushandiswa kwemhepo yakadzika, mvura haibvumirwi (V4 uye V5 yakavharwa).
3_) Drained samples_. Muenzaniso unodonhedzwa kwenguva yose yekuedzwa (mavharuvhu V4 uye V5 akazaruka), kuitira kuti kubatanidzwa kwakakwana kuitike uye hapana mvura yakasimbiswa inogadzirwa mumapores panguva yekushandiswa kwe vertical pressure σ1. Muedzo uyu unotora nguva yakareba, kunyanya nevhu risingapindike zvakanaka, nekuti kurodha kwakamira σ1 kunofanirwa kuitwa muhuwandu hwematanho madiki uye kubatanidzwa kunofanirwa kumirira padanho rega rega. Pamusoro pezvo, bvunzo dzataurwa dzinogona kuitwa ne saturated uye partially saturated samples_._
Tichifunga nezvezvambotaurwa zvinogoneka, triaxial compression bvunzo inogona kuitwa mumhando dzakasiyana uye kugadziridzwa zvichienderana nerudzi rwevhu pasi pekuremerwa.
Midziyo, maitirwo, mayuniti, kukosha uye mapatani anotsanangurwa anotamiswa kubva kunhoroondo kunobva. Chinyorwa hachisi chidzidzo che geotechnical, laboratory protocol, nheyo yeprojekti, humbowo hwekudzikama kwemateru kana chirongwa chekuchera. Sarudzo yemuenzaniso uye nzira yekuyedza, mamiriro emvura nekubatanidzwa, mvura yepasi, kutonga kwemutoro, kudengenyeka kwenyika uye kuchengetedza kwekuchera kunofanirwa kutariswa kune chaiyo ivhu uye chivakwa, zvinoenderana nemirairo iripo, nerabhoritari yakakodzera uye nemvumo ye geotechnical nyanzvi.