Kuphatikizika kwa nthaka

Zomwe zili muakatswiri wazakale: Nkhaniyi ikusunga mbiri yakale ya malingaliro a geotechnical, ma formula ndi njira za labotale. Si kafukufuku wa geotechnical, kamangidwe ka mpanda, kafotokozedwe ka zinthu, dongosolo lowongolera bwino, kapena kulowetsa mulingo wapano. Magawo a nthaka, zida, mphamvu zophatikizira, njira zovomerezera ndi njira zotetezeka zogwirira ntchito zimatsimikiziridwa ndi mainjiniya ovomerezeka a geotechnical ndi labotale yovomerezeka yotengera dothi ndi chinthu.

Masiku ano, Savo Kusić amayang’ana kwambiri mazenera amatabwa, mazenera a matabwa a aluminiyamu, mazenera amwambo, khomo ndi zopempha za mawu. Nkhaniyi ikhalabe ngati mbiri yakale yaukadaulo ndipo siyikuyimira kuperekedwa kwa mapangidwe a geotechnical, kuyesa kapena kugwirira ntchito kwa nthaka.

Kumanga kwa dothi lotayirira

Kukhazikika kwa dothi lotayirira kumadalira kukula ndi mawonekedwe a tinthu tating’onoting’ono, komanso kapangidwe kake. Pankhani ya dothi losamangidwa, pali malire ena momwe porosity n ndi porosity coefficient e pazosowa komanso zolimba kwambiri zimasuntha.

Ngati zinthu zosamangidwazo zawuma ndikutsanuliridwa pang’onopang’ono mu beaker kuti zisagwirizane panthawi yothira, rarest structure yake imapezeka. Kapangidwe kameneka kamafanana ndi porosity coefficient emax, yomwe mtengo wake wamchenga m’mawu oyamba uli mkati mwa malire:

max =0,7-1,0.

Ngati zinthu zomwezo zatsanuliridwa mu beaker mu zigawo zoonda ndipo wosanjikiza uliwonse wazunguliridwa ndi mallet mpaka voliyumuyo itakhazikika, i.e. mpaka itasiya kukhazikika pansi, denseest structure yake imapezedwa. Imafanana ndi porosity coefficient emin, yomwe mtengo wake wamchenga ndi:

emin = 0,45–0,65.

Kuphatikizika kwa nthaka yosamangika kumasonyezedwa ndi kukanikizana ID, kagawo kamene kamasonyeza kuchuluka kwa kukanikizika kwa nthaka kutengera kuphatikizika kwapamwamba kwambiri:

kumene e ndi dothi la porosity coefficient mu chikhalidwe cha chilengedwe cha compaction. Makhalidwe omaliza a kachulukidwe wachibale ndi awa:

• pamapangidwe osowa e = emax; ID =0;
• chifukwa cholimba kwambiri e = emin; ID =1.

Muyeso wa kuphatikizika kwa dothi lamchenga malinga ndi Terzaghi m’mawu oyamba akuti:

• mchenga wosakanizidwa pang’ono: ID =0-1/3;
• mchenga wopindika wapakatikati: ID =1/3–2/3;
• mchenga wothinana kwambiri: ID =2/3-1.

Pankhani ya mizati pa misewu ndi mizati, malemba amafuna ID =2/3-1.

M’malo mwa mawonekedwe am’mbuyomu, chiŵerengero cha mavoliyumu chingagwiritsidwe ntchito:

pomwe V ndi kuchuluka kwa dothi losasokonezedwa, Vmax ndi kuchuluka kwa dothi lofanana ndi lomwe silimapindika pang’ono, ndipo Vmin ndi kuchuluka kwa dothi lomwe likamangika kwambiri.

Malire ogwiritsira ntchito: Magulu akale ndi mawu sangatumizidwe mwachindunji ku polojekiti kapena malo omanga. Mtundu wa dothi, njira yotengera zitsanzo, momwe zilili, mulingo woyenera ndi zofunikira za polojekiti zitha kusintha njira ndi njira.

Kumanga kwa dothi lomangidwa

Ndi dothi lomangika, kupondana sikudalira kokha kukula ndi mawonekedwe a zosakaniza zolimba ndi kapangidwe kake, komanso kugwirizanitsa. Chifukwa cha kugwirizana, tinthu tating’onoting’ono timamatira pamodzi, kotero kuti kufinya madzi kuchokera mu pores panthawi yophatikizana kumakhala kovuta kwambiri kusiyana ndi nthaka yosamangika, yomwe tinthu tating’onoting’ono timayenda mosavuta pansi pa katundu.

Pomanga nthaka yomangidwa, kuchuluka kwa madzi kumakhala kofunika kwambiri. Ndi tamping, madzi amakakamizika kutuluka mu pores ndipo makulidwe a filimu yamadzi amachepa; porosity imachepa, ndipo kumeta ubweya wa mphamvu ndi kachulukidwe kochuluka kumawonjezeka. Kuchuluka kwa kachulukidwe, kumakhala kolimba kwambiri ndi ma pores ochepa pa voliyumu ya unit. Chiŵerengerochi chinatengedwa ngati maziko ounikira kaphatikizidwe ka dothi lomangika. Kuwongolera kwapang’onopang’ono pamawu kumachitika pogwiritsa ntchito kulemera kwa volumetric:

γd = Wd / V [N/cm3]

kumene Wd ndi kulemera kwa dothi lowumitsidwa mu N, ndipo V ndi kuchuluka kwa nyemba zomwezo zikaphatikizika musanawume, mu cm3.

Mayesero a Proctor

Mayeso a Proctor amatsimikizira kugwirizana pakati pa kuchuluka kwa madzi munthaka ndi kuphatikizika kwake. Zimatsimikizira unyezi wabwino kwambiri, mwachitsanzo, chinyezi chomwe dothi lopindika limapereka kulemera kwakukulu kowuma kwa mphamvu yophatikizika.

Adafotokozera kale zida za Proctor (Chith1) imakhala ndi silinda yachitsulo yokhala ndi mainchesi amkati Ø =10 cm, kutalika12 cm(chithunzi1_a_), kupitiriza kwa silinda yofanana kutalika kwake10 cm(chithunzi1_b_) ndi mainchesi achitsulo5 cm, kulemera2,5N, mu kalozera wozungulira wokhala ndi mainchesi okulirapo pang’ono. Chowongoleracho chimatsegulidwa kumapeto chakumunsi ndikutsekedwa chakumtunda, ndikutsegula pang’ono kuti chogwirira cha nkhosa champhongo chidutse (chithunzi.1_c_). Mapeto apansi a silinda amaikidwa pa mbale yayikulu yachitsulo ndikukhazikika panthawi ya tamping.

Chitsanzocho chimawuma molingana ndi ndondomeko yoyamba ndikusefa kudzera mu sieve5 mmkupewa kutengera mbewu zazikulu. Kenako imasakanizidwa ndi kuchuluka kwa madzi omwe sayenera kukhala ochuluka kwambiri kotero kuti chitsanzocho chimakhala mushy, kapena chochepa kwambiri kotero kuti chitsanzocho sichikhoza kukonzedwa. Choyamba, wosanjikiza ndi kutalika kwa pafupifupi8 cmmu chikhalidwe chosaphatikizika ndi rammed ndi25zikwapu wogawana anagawira pamwamba. Mphamvuyi imachitidwa ndi kugwa kwaulere kwa mallet kuchokera pamtunda30 cm. Chigawo chatsopano cha makulidwe chimagwiritsidwa ntchito8 cm, amalipiritsa ndi atsopano25kugunda ndi kubwereza ndondomekoyi ndi gawo lachitatu. Pambuyo pomaliza, kufalikira kumachotsedwa, pamwamba pa chitsanzocho chimagwirizana ndi m’mphepete mwa silinda yapansi, ndipo nthaka yowonjezera imachotsedwa. Chitsanzo cha dothi loumbika chimachotsedwa ndipo kachulukidwe kake kouma γd ndi chinyezi w zimatsimikiziridwa.

Chithunzi1- Kuyesa kwa Proctor.

Kuyesaku kumabwerezedwa 5 mpaka 6 nthawi, nthawi zonse ndi zinthu zatsopano, zosasinthidwa kuchokera ku chitsanzo chomwecho, koma ndi kuchuluka kwa madzi, kuti apeze misinkhu yosiyanasiyana ya γd ndi w. Chinyezi cha dothi w chimayikidwa pa abscissa pa chithunzicho, ndi kulemera kwake kwa volumetric γd pa ndondomeko (chithunzi 2). Mfundo zolumikizidwa zimapereka mpiringidzo wosonyeza kuti kachulukidwe kowuma kowuma kaŵirikaŵiri kumawonjezeka ndi chinyezi mpaka pamlingo waukulu ndiyeno kumachepa. Chinyezi wopt chogwirizana ndi kusachulukira kouma kwambiri max γd kumatchedwa optimal humidity. M’malembawo, amavomereza kuti pa chinyezi ichi, kuphatikizika kwapamwamba kwambiri kumatheka chifukwa cha mphamvu yopatsa mphamvu. Mayeso omwe amachitidwa motere amatchedwa standard Proctor’s test.

Chithunzi 2 - Chithunzi cha Proctor.

Chitetezo cha labotale ndi muyezo: Makulidwe a zida, kulemera ndi kutsika kwa rammer, kuchuluka kwa zigawo ndi zotsatira zake ndi kukonzekera zitsanzo ndi mbiri yakale yofalitsidwa pano, osati malangizo odziyimira okha. Njira yovomerezeka iyenera kufotokozera ndondomeko yoyenera ndi ndondomeko ya labotale. Kuyanika, kusefa ndi kupondaponda kumanyamula zoopsa kuchokera ku fumbi, tinthu tating’onoting’ono towuluka, kukanidwa ndi kuvulala kwamphamvu; zida zoyenera, chitetezo ndi wogwiritsa ntchito wophunzitsidwa amafunikira.

Kukula kwambewu kupitilira 5 mm

M’mawu oyamba, akuti njere zazikulu kuposa 5 mm sizikhala ndi vuto lalikulu ngati zipanga 25% pa kuchuluka kwake. Ngati pali zoposa 25%, mphamvu zawo ziyenera kuganiziridwa powerengera kulemera kwake kwa volumetric wa osakaniza pogwiritsa ntchito njira yofananira kapena kuyesa kwa Proctor kosinthidwa.

Kuwerengera molingana ndi njira

Malinga ndi njirayi, kulemera kwa voliyumu yowuma ya dothi losakanizika γdm kumawerengeredwa potengera kuchuluka kwa mbewu zopitirira ndi pansi.5 mm:

kuti:

• γd - kulemera kwa volumetric kwazinthu zomwe zidadutsa pazenera5 mm;
• γsc - kulemera kwa voliyumu ya tinthu zolimba zotsalira pazenera lotsegulira5 mm;
• m - peresenti ndi kulemera kwa zinthu zomwe zatsala pa sieve kutsegula5 mmmogwirizana ndi misa yonse.

Mayeso osinthidwa a Proctor

Malinga ndi zochitika za US Bureau of Reclamation zotchulidwa m’mawu oyambirira, ngati mbewu zazikulu kuposa5 mmsinthani1/3ku2/3pa kuchuluka kwa nthaka, kuyesedwa kuyenera kuchitidwa ndi misa yonse. Popeza sizingatheke kuchita izi bwinobwino mu silinda ya m’mimba mwake10 cm, silinda yokulirapo imagwiritsidwa ntchito muzomwe zimatchedwa modified Proctor test. Mawuwa akufotokoza silinda ya diameter15,2 cmndi kutalika23,2 cm, momwe kuchuluka kwachitsanzo5,5kp imadzaza magawo atatu pafupifupi ofanana ndi po50amagunda ndi nyundo yolemera4,53kp ndi kutalika kwake45,7 cm. Ngati chitsanzocho chili ndi mbewu mpaka20 mm, mayesowa amachitidwa ndi zinthu zosasokoneza. Ngati muli mbewu zazikulu kuposa20 mm, kuchuluka kwa5,5kp wa chitsanzo amasefa mu sieve wa20 mm, ndikusintha zina zonse pa sieve ndi zinthu zofanana5-20 mm.

Kuphatikiza pa ndondomeko yomwe yafotokozedwa motere, m’malembawo njira iliyonse yogwirira ntchito yomwe imasiyana ndi muyezo imatchedwanso mayeso osinthidwa a Proctor.

Mphamvu yamagetsi

Mphamvu yophatikizika yachitsanzo mu silinda ya Proctor imatha kuwonetsedwa ndi equation, pomwe N ndi kuchuluka kwa nyundo, h ndi kutalika kwa nyundo mu m, W ndi kulemera kwa nyundo ku Mp (megapond), ndipo V ndi kuchuluka kwa zitsanzo mu m.3.

Ndi kuwonjezeka kwa mphamvu ya compaction, kusakanikirana kwakukulu kwa chitsanzo kumatheka, porosity yake, mwachitsanzo, kuchuluka kwa madzi m’nthaka, kumachepa, ndipo kulemera kwa voliyumu youma kumawonjezeka. Kwa compaction mphamvu E1, E2, E3ndi E4ziwembu zofananira za Proctor pachithunzichi zimapezedwa3. Zithunzi zonse zimayamba mosagwirizana ndi machulukitsidwe, omwe amatchedwanso chithunzi0%pores mpweya pamene pores onse amadzazidwa ndi madzi, mwachitsanzo5%wa pores mpweya pamene izo95%pores wodzazidwa ndi madzi.

Chithunzi3- Zithunzi za Proctor zamphamvu zosiyanasiyana zophatikizira.

Chithunzi cha machulukitsidwe chikhoza kupangidwa pojambula pa abscissa w = wz = n / γs(1-n), ndi pa gulu γd = γs(1-n), pamene n ndi porosity ya nthaka, ndipo γs ndi kulemera kwa volumetric kwa tinthu tating’ono ta nthaka yomwe wapatsidwa. Izi zikutsatira kuti mphamvu ya compaction ingasinthidwe kuti ipeze compaction yomwe mukufuna. Kuwongolera kuphatikizika kwa dothi lachilengedwe kapena mpanda wopindika, index compaction Iz nthawi zambiri imatengedwa m’mawu, chiŵerengero cha kulemera kwa voliyumu ya dothi lomwe mwapatsidwa kapena phula γd ku kulemera kwa volumetric komwe Proctor γp:

Iz = γd / γp.

** Kupanga ndi kulamulira m’munda: ** ma curve a labotale okha samatsimikizira ubwino wa gawo lochokera. Zitsanzo, makulidwe osanjikiza, mtundu ndi kuchuluka kwa makina odutsa, chinyezi, miyeso yamunda, mphamvu yonyamula, ngalande, nyumba zoyandikana ndi kuyika mobisa ziyenera kuphatikizidwa pakupanga ndi kuwongolera dongosolo. Musayandikire malo ogwirira ntchito a roller kapena makina ena popanda kusaina ndi kuwongolera njira.