Lokacin zayyana tsarin ƙunshewar ƙasa, yana da sauƙi a mai da hankali kawai akan ƙayyadaddun ƙirar geomembrane kanta-kaurinsa, kayansa, da ƙarfin kubu. Duk da haka, aikin dogon lokaci na wannan layin yana da tasiri sosai daga yanayin da aka sanya shi. Mahimmanci guda uku, kuma sau da yawa ba a kula da su ba, abubuwa - lissafin rukunin yanar gizon da tushe - suna da mahimmanci kamar kayan da kuka zaɓa. Waɗannan su ne gangaren ƙasa, girman tantanin halitta, da ingancin ƙasa.
Kamar yadda a geosynthetics maroki, Mun ga kai tsaye yadda za a iya lalata tsarin layin layi mai haske ta hanyar ƙarancin ƙirar geometric ko tushe mara ƙarfi. Layin layi ba keɓantacce bane; wani bangare ne na tsarin mu'amala mai sarkakiya. Fahimtar wannan dangantakar shine mabuɗin don ƙirƙira tsarin tsarewa waɗanda ba wai kawai sun dace da ranar ɗaya ba, amma aminci da tasiri na shekaru da yawa. Wannan jagorar yana bincika mahimmancin tasiri na gangara, girman tantanin halitta, da raguwa akan aikin layi, yana ba da ƙa'idodin injiniyan da kuke buƙata don daidaita shi.
Bari mu fara da yin la'akari da yadda kusurwar ƙasa a ƙarƙashin layin layi ke nuna kwanciyar hankali da ingancinta.
1. Muhimman Tasirin Gangamin Fassara akan Ayyukan Liner
Matsakaicin kusurwa shine aikin daidaitawa tsakanin ingantaccen magudanar ruwa da kwanciyar hankali na inji. Bangarorin daban-daban na ƙasƙan ƙasa suna buƙatar gangara daban-daban, kowanne yana da takamaiman aiki.
| Nau'in gangara | Na Musamman Range | Aiki | Mabuɗin Bukata |
|---|---|---|---|
| Tudun Gindi | 2% - 4% | Leachate Magudanar ruwa | ≥1% a tsaye, ≥3% juye zuwa bututu |
| Gefen Gefe | 1V: 3H - 1V: 2.5H | Kwanciyar Sharar Jama'a | Factor na Tsaro (FOS) ≥ 1.5 |
| Murfin Karshe | ≤ 1V: 3H | Hana zaizayar kasa | Taimakawa ciyayi, sarrafa kwararar ruwa |
Lura: 1V: 3H yana nufin mita 1 a tsaye don kowane mita 3 a kwance.
Ingantaccen Magudanar Ruwa da Leachate
Babban manufar gangaren gindin shine a yi amfani da nauyi don karkatar da zubewa zuwa bututun tarawa. Ingancin wannan tsari yana ƙarƙashin Dokar Darcy's, wanda ke gaya mana cewa yawan kwararar ruwa ya yi daidai da na'urar ruwa - a wannan yanayin, gangaren layin.
Matsakaicin gangare yana nufin magudanar ruwa da sauri da kuma ƙananan kan leachate (zurfin ruwa zaune akan layin). Wannan yana da mahimmanci don rage haɗarin yaɗuwa.
- Tudu (misali, 4%): Leachate magudanar ruwa da sauri, ajiye shugaban kasa 100 mm.
- Zuciyar Zuciya (misali, 2%): Magudanar ruwa yana da hankali, kuma kai zai iya tashi zuwa 300 mm, wanda yawanci shine iyakar da aka yarda.
- Lebur Tudu (<1%): Mahimmin haɗaɗɗiya yana faruwa, mai yuwuwar wuce iyakar 300 mm kuma yana ƙaruwa da matsa lamba akan layin layi da rigunan sa.
Ka'idojin ƙasa da ƙasa, gami da na EPA na Amurka, yawanci suna ba da umarni mafi ƙarancin gangara 1% tare da bututun tattara leach da 2% – 4% gangara mai juyewa (a kai tsaye) zuwa gare su don tabbatar da sarrafa kan leached.
Tsallakewa da Kwanciyar Hankali
Yayin da gangare mai tsayi yana da kyau ga magudanar ruwa, yana haifar da babban haɗarin kwanciyar hankali ga gangaren gefen. Nauyin tsarin layin layi, ƙasa mai rufewa, da sharar gida da kanta ta haifar da ƙarfin nauyi ( sojojin tuƙi) waɗanda ke son ja da ƙasa gaba ɗaya. Dakarun masu adawa da juna suna fuskantar wannan a wurare daban-daban a cikin tsarin layin layi.
Injiniyoyin suna nazarin wannan ta amfani da a Iyakance Hanyar Daidaituwa don lissafin Factor of Safety (FOS):
FOS = Resisting Forces / Driving Forces
FOS na 1.0 yana nufin tsarin yana gab da gazawa. Tsarin aminci yana buƙatar FOS ≥ 1.5. Sojojin da ke juriya sun dogara sosai akan kusurwoyin da ke tsakanin yadudduka (misali, geomembrane-zuwa-GCL, GCL-zuwa-subgrade). Matsakaicin kusurwa mai gangare yana ƙara ƙarfin tuƙi, yana sanya tsarin cikin haɗarin gazawar. Saboda wannan dalili, gangaren gefen da wuya ba a tsara su sama da 1V: 2.5H (kimanin. 22°) ba tare da cikakken nazarin ilimin geotechnical da yuwuwar ƙarfafawa ba.
2. Yadda Girman Tantanin Halitta ke Tasirin Matsalar Liner da Ingantaccen Tsarin
A landfill is typically constructed in discrete phases, or "cells." Tantanin halitta yanki ne mai cikakkar ƙunshe da nasa layin leachate tarin tsarin. Girman waɗannan ƙwayoyin suna da tasiri mai mahimmanci akan gini, ayyuka, da aiki.
| Girman Tantanin halitta | Matsakaicin Girma (m³) | Aikace-aikacen gama gari |
|---|---|---|
| Karami | 50,000 - 200,000 | Tsarin tsari; mai kyau don keɓantawar zubewa |
| Matsakaici | 200,000 - 1,000,000 | Mafi yawan girman gama gari, daidaita dacewa da gudanarwa |
| Babba | > 1,000,000 | Manyan kayan aiki; mafi hadaddun leachate management |
Girman Tantanin halitta da Tarin Leachate
Girma da siffar tantanin halitta kai tsaye suna tsara shimfidar hanyar sadarwar bututun leachate. Dokoki galibi suna buƙatar tazarar bututun da bai wuce mita 25-50 ba don kiyaye kan leach ɗin ƙasa da iyakar 300 mm.
Wannan yana nufin babban tantanin halitta baya buƙatar dogon bututu kawai; yana bukata Kara daga cikinsu, yana haifar da tsari mai rikitarwa. Faɗin ƙasan tantanin halitta yana ƙara iyakar nisan tafiya don lechate, wanda zai iya haifar da matakan kai mafi girma tsakanin bututun magudanar ruwa.
Girman Tantanin halitta da Shigarwa na Liner
- Manyan Kwayoyin: A gefe guda, manyan, wuraren buɗewa suna ba da izinin tura fa'idodi masu inganci na geosynthetic, tare da ƙarancin tsayawa da farawa. A gefe guda kuma, sun fi dacewa da ƙalubale daga faɗaɗa zafin zafi da raguwa. A rana mai zafi, rana, babban ɓangaren geomembrane da aka fallasa zai iya haɓaka manyan wrinkles. Idan ba a sarrafa waɗannan wrinkles kuma an rufe su, za su iya zama wuraren babban damuwa da rashin gazawa.
- Ƙananan Kwayoyin: Ƙananan ƙwayoyin sel suna sauƙaƙe sarrafa wrinkles amma suna ƙara yawan yawan ɗinku dangane da yankin. Wannan yana nufin ƙarin walda, ƙarin gwajin QA/QC, da ƙari mafi girma na yuwuwar maki masu rauni idan ba a shigar da su daidai ba.
Don waɗannan dalilai, galibin wuraren shara na zamani an ƙirƙira su ne ta hanyar amfani da tsarin lokaci, tsarin sel da yawa. Wannan yana ba da sassaucin aiki, yana ba da damar keɓancewa cikin sauri, kuma yana sa sarrafa leachate da iskar gas mafi inganci.
3. Matsayin Tushen Nagartar Rarraba Ƙarfafa don Mutuncin Liner
Ƙarƙashin ƙasa—tushen ƙasa da aka shirya akansa wanda aka gina tsarin layin-shine mafi ƙarancin ƙimar tsarin tsarin. Rashin ƙarancin ƙasa na iya haifar da gazawar layi ba tare da la'akari da ingancin geosynthetics ba.
Ƙarfafa Ƙarfafawa da Ƙarfin Ƙarfafawa
Ƙarƙashin darajar dole ne ya samar da tsayayye, dandali mara jurewa. Rashin cikawa shine babban dalilin matsalolin gaba.
| Matsayin Matsayi | Mafi Karancin Ƙarfafawa (Proctor) | Manufar |
|---|---|---|
| Tushen | ≥95% MDD | Yi tsayayya da matsa lamba mafi girma daga yawan sharar gida |
| Gefen gangara | 90% MDD | Hana sloughing da tabbatar da kwanciyar hankali |
Idan subgrade ba shi da kyau sosai, zai daidaita ba daidai ba a ƙarƙashin babban nauyin sharar gida (wanda zai iya wuce 600 kPa). Wannan bambancin sulhu yana shimfiɗa geomembrane a kan wuraren da aka nutse, yana haifar da matsanancin damuwa wanda zai iya haifar da tsagewa da gazawa.
Shirye-shiryen Subgrade Surface
Dole ne mai layi ya kasance yana da kusancin hulɗa tare da ƙaramin ƙima. Dole ne saman ya kasance:
- Mai Santsi Kuma Babu tarkace: Duk duwatsun da suka fi milimita 12, saiwoyin, da abubuwa masu kaifi dole ne a cire su.
- Ko da: The surface should be graded to a tolerance of about +/- 25 mm to prevent the liner from "bridging" a kan banza.
- Ƙarfafawa da kyau: Ƙaƙƙarfan wuri yana hana kayan aikin gine-gine ƙirƙirar ruts mai zurfi wanda zai iya jaddada layin layi.
Layer matashin matashin geotextile wanda aka sanya kai tsaye a kan matakin ƙasa yana da mahimmanci don kare geomembrane daga duk wani lahani.
Ƙarfin Ƙarfin Ƙarfin Ƙarfafawa
The friction between the liner system and the subgrade is a key component of slope stability. This "interface shear strength" ana auna a cikin dakin gwaje-gwaje kuma yana da mahimmanci ga Factor of Safety lissafin. Ƙaƙwalwar yumbu mai santsi, rigar ƙasa za ta sami ƙaramin kusurwar juzu'i tare da geomembrane idan aka kwatanta da granular, ƙanƙarar ƙanƙara, yana mai da shi ƙasa da dacewa da gangaren tudu.
4. Tasirin Haɗin kai: Gudanar da gangara, Girman Tantanin halitta, da Ragewa
Wadannan abubuwa guda uku ba sa aiki a ware. Haɗin tasirin su yana ƙayyade aikin gaba ɗaya da amincin tsarin.
| Halin yanayi | gangara | Leachate Head | Ƙarfafa Ƙarfafawa | Sakamako (Dalili na Tsaro) |
|---|---|---|---|---|
| Mafi kyawu | Tsaki (4%) | Ƙananan (<100 mm) | Madalla (≥95% Compaction) | FOS > 2.0 (Mai Aminci) |
| Na gefe | Matsakaici (2%) | Babban (300 mm) | Yana da kyau (90%) | FOS ≈ 1.5 (Kallon a hankali) |
| Mai haɗari | Shallow (1%) | Mafi Girma (>300 mm) | Talakawa (<90% Ƙarfafawa) | FOS < 1.5 (Babban Haɗarin gazawa) |
Kyakkyawan ƙira tsari ne na maimaitawa:
- An gabatar da tsarin gangare na farko da tsarin tantanin halitta.
- An tsara tsarin sarrafa leachate don kiyaye kai ƙasa da 300 mm.
- An ƙayyadadden buƙatun ƙasa.
- Ana yin nazarin kwanciyar hankali (FOS).
- Idan FOS ya yi ƙasa da ƙasa, dole ne mai zane ya yi canji: rage kusurwar gangara, inganta matakin ƙasa, ko ƙara ƙarfafawa. Ana maimaita wannan tsari har sai an cika duk ƙa'idodin aminci da aiki.
Ƙarshe
An gina ingantaccen tsarin shimfidar ƙasa a kan ginshiƙi na ƙirar geotechnical mai sauti da ƙirar geometric. Ta hanyar yin la'akari da hankali a kan mu'amala tsakanin kusurwar gangare, daidaitawar tantanin halitta, da ingancin ƙasa, za ku wuce zaɓin abu kawai. Kai injiniya ne cikakke, tsarin haɗin kai wanda aka tsara don kwanciyar hankali na dogon lokaci da kare muhalli. Kula da waɗannan abubuwan tushe tun daga farko ita ce hanya mafi inganci don tabbatar da mutunci da dawwama na gabaɗayan rumbun ƙasa.
