Hauv txoj kev hauv nroog, cov kav dej hauv tsev, thiab cov chaw ua si, cov kav dej ntawm cov kav dej thiab cov kav dej, txawm tias zoo li tsis tseem ceeb, yog cov khoom siv tseem ceeb rau kev thauj khoom -kev nyab xeeb thiab cov dej ntws zoo. Ntau qhov chaw tsim kho tau ntsib qhov xwm txheej uas grate deform, tawg, tawg, lossis txawm tawg hauv lub tsheb siab sai tom qab kev teeb tsa. Txawm hais tias qhov no yuav tshwm sim vim qhov tsis zoo ntawm grating, qhov teeb meem feem ntau nyob hauv ntau qhov yooj yim saib tsis tau.
Ua ntej thiab foremost, qhov teeb meem ncaj qha tshaj plaws yog cov khoom siv tsis zoo.
Cov kua dej uas tsim nyog tiag tiag yuav tsum siv cov hlau nplaum QT500-7 lossis qib siab dua. Cov graphite yog spherical, ua rau muaj zog siab, zoo toughness, thiab tsis kam mus rau siab thiab cuam tshuam. Txawm li cas los xij, ntau yam khoom siv qis- tus nqi qis hauv khw, txhawm rau txo cov nqi, siv cov hlau cam grey, cov khoom siv rov ua dua tshiab, lossis cov khoom siv sib xyaw nrog lwm cov impurities. Cov ntaub ntawv no yog nkig thiab tsis txaus elongation; Txawm hais tias lawv yuav zoo li tuab txaus, lawv tawg nyob rau hauv kev ntxhov siab thiab ua tsis tau raws li qhov xav tau ntawm kev tsim khoom.
Qhov thib ob, muaj qhov tsis xws luag hauv cov qauv tsim thiab cov txheej txheem casting.
Qee cov gratings tuaj yeem ua tau raws li cov qauv sab nraud, tab sis lawv cov rib sab hauv yog tsis tsim nyog, rib dav tsis txaus, cov ntsiab lus kev ntxhov siab tsis muaj zog, los yog qhov sib txawv ntawm cov grate loj dhau, ua rau tsis txaus tag nrho cov rigidity. Nyob rau hauv kev ntxhov siab, lawv nquag mus rau hauv zos deformation thiab sagging.
Shrinkage kab noj hniav, porosity, cua hnab ris, thiab txias kaw uas tshwm sim thaum lub sij hawm casting txheej txheem ncaj qha ua rau cov khoom ncaj ncees. Cov teeb meem sab hauv no yog qhov nyuaj rau kev kuaj pom ntawm qhov muag liab qab, tab sis ib zaug raug rau lub tsheb thauj khoom, lawv yuav tawg ntawm cov ntsiab lus tsis muaj zog, ua rau tag nrho tsis ua haujlwm.
Thib peb, cov lus qhia tshwj xeeb uas tau xaiv tsis phim qhov kev siv tiag tiag.
Qhov no yog ib qho kev xav tsis zoo heev. Ntau tus neeg tsuas yog xav txog "yog tias nws ua haujlwm," yam tsis tau xaiv raws li kev thauj khoom -cov kabmob muaj peev xwm:
Rau kev taug kev thiab txoj siv tawv ntsuab, lub teeb yuag lossis zoo tib yam gratings txaus;
Rau txoj kev nyob hauv tsev thiab txoj kab qeeb, nruab nrab load- yuav tsum muaj peev xwm;
Rau txoj kev loj hauv nroog, txoj kab hluav taws xob, thiab hnyav- thaj chaw ua haujlwm, hnyav-lub luag haujlwm lossis super- hnyav- cov khoom siv yuav tsum raug xaiv.
Siv lub teeb yuag gratings ntawm txoj kev tsav tsheb, txawm tias cov khoom nws tus kheej tsim nyog, yuav ua tsis tau sai vim yog ntau tshaj qhov tsim qauv.
Plaub, lub hauv paus kev teeb tsa tsis ruaj ntseg, thiab kev saib xyuas tom ntej yog tsis muaj.
Lub load-cov kabmob muaj peev xwm ntawm geogrid tsis yog nyob ntawm cov khoom nws tus kheej nkaus xwb tab sis kuj nyob ntawm nws qhov kev teeb tsa thiab kev txhawb nqa.
Yog hais tias lub manhole npog los yog lub hauv paus mortar tsis puv, qhov chaw txhawb nqa tsis sib xws, lub thav duab raug kev ntxhov siab tsis sib xws, los yog ib puag ncig ntawm txoj kev yog xoob lossis muaj kev sib haum xeeb tsis sib xws, geogrid yuav raug tshem tawm thiab raug eccentric kev nyuaj siab thaum lub tsheb tsav dhau nws. Qhov kev ntxhov siab tam sim ntawd hauv qee qhov chaw yuav nyob deb tshaj tus nqi tsim, yooj yim ua rau deformation thiab kev puas tsuaj.
Tsis tas li ntawd,ntev -ntev raug cov dej phwj tuaj, roj, kua qaub, thiab alkalis, ua ke nrog lub caij ntuj no khov -thaw cycles thiab lub caij ntuj sov kub kub, yuav ua rau lub geogrid maj mam muaj hnub nyoog, corrode, thiab nyias, ua rau ib tug txo nyob rau hauv load- bearing muaj peev xwm txhua xyoo. Kev tshuaj xyuas thiab hloov tsis tau raws sijhawm yuav ua rau kev thauj khoom -cov kabmob tsis ua haujlwm.
Thaum kawg, hloov tus nqi qis rau cov qauv thiab tsis quav ntsej txog kev xeem yog ib qho teeb meem tshwm sim.
Ntau qhov haujlwm tsuas yog sib piv cov nqi, tsis quav ntsej saib cov ntawv xeem thiab txheeb xyuas cov cim tseem ceeb xws li thauj khoom- bearing lub zog, cov khoom muaj pes tsawg leeg, thiab cov khoom siv tshuab. Yog tias tsis muaj kev tshuaj xyuas lub Hoobkas, qhov thib peb- kev sim thib peb, cov khoom lag luam pom tseeb, thiab daim ntawv pov thawj ntawm kev ua raws, kev siv cov geogrid hauv cov haujlwm yuav ua rau muaj kev cuam tshuam tsis zoo ntawm cov khoom thauj -cov kabmob muaj peev xwm thiab kev nyab xeeb.
Hauv kev xaus,qhov tsis ua haujlwm ntawm cov ntxaij lim dej kom ua tau raws li cov qauv thauj khoom- cov qauv kabmob tsis yog ib qho teeb meem xwb, tab sis qhov tshwm sim ntawm kev sib xyaw ua ke nrog rau cov khoom siv, kev tsim khoom, kev xaiv, kev teeb tsa, thiab kev tswj hwm. Tsuas yog los ntawm kev siv cov khoom siv hlau hlau, xaiv qhov raug load- cov kabmob muaj peev xwm rau qhov xwm txheej tshwj xeeb, txhim kho lawv raws li cov lus qhia tshwj xeeb, thiab kev ua haujlwm tsis tu ncua tuaj yeem ua tiav kev nyab xeeb, ruaj khov, thiab ntev - lub sijhawm ruaj khov, zam cov nqi ntau dua cuam tshuam nrog kev kho dua thiab hloov tom qab.