xov xwm

Ua tsaug rau koj tuaj xyuas cov khoom siv iav fiber ntau cabron.Koj siv lub browser version nrog kev txhawb nqa CSS tsawg.Rau qhov kev paub zoo tshaj plaws, peb xav kom koj siv qhov browser tshiab (lossis lov tes taw Compatibility Hom hauv Internet Explorer).Tsis tas li ntawd, txhawm rau xyuas kom muaj kev txhawb nqa tsis tu ncua, peb qhia lub vev xaib tsis muaj qauv thiab JavaScript.
Polymer-reinforced qhob (FRP) yog suav tias yog ib txoj kev tshiab thiab kev lag luam ntawm kev kho cov qauv.Hauv txoj kev tshawb no, ob yam khoom siv [carbon fiber reinforced polymer (CFRP) thiab iav fiber reinforced polymer (GFRP)] tau raug xaiv los kawm txog cov txiaj ntsig ntawm kev ua vaj tse nyob rau hauv ib puag ncig hnyav.Qhov kev tiv thaiv ntawm cov pob zeb uas muaj FRP rau sulphate nres thiab cuam tshuam txog lub voj voog khov-thaw tau tham.Electron microscopy los kawm txog qhov chaw thiab sab hauv degradation ntawm pob zeb thaum lub sij hawm kev sib tsoo.Lub degree thiab mechanism ntawm sodium sulfate corrosion tau soj ntsuam los ntawm pH tus nqi, SEM electron microscopy, thiab EMF zog spectrum.Axial compressive zog kuaj tau siv los ntsuas qhov kev txhawb zog ntawm FRP-constrained qhob txhua kab, thiab kev ntxhov siab-kev sib raug zoo tau muab los rau ntau txoj hauv kev ntawm FRP tuav hauv ib puag ncig erosive coupled.Kev soj ntsuam yuam kev tau ua los ntsuas qhov kev sim ntsuas qhov ntsuas uas siv plaub tus qauv ntsuas uas twb muaj lawm.Tag nrho cov kev soj ntsuam qhia tau hais tias cov txheej txheem degradation ntawm FRP-txhim kho pob zeb yog qhov nyuaj thiab muaj zog nyob rau hauv kev sib txuas lus.Sodium sulfate pib nce lub zog ntawm pob zeb hauv nws daim ntawv nyoos.Txawm li cas los xij, tom qab lub voj voog khov-thaw tuaj yeem ua rau pob zeb tawg, thiab sodium sulfate ntxiv txo lub zog ntawm pob zeb los ntawm kev txhawb kev tawg.Tus qauv lej raug raug npaj los simulate kev sib raug zoo ntawm kev ntxhov siab, uas yog qhov tseem ceeb rau kev tsim thiab ntsuas lub neej voj voog ntawm FRP-constrained pob zeb.
Raws li txoj kev tsim kho tshiab uas tau tshawb fawb txij li xyoo 1970s, FRP muaj qhov zoo ntawm lub teeb yuag, siab zog, corrosion kuj, qaug zog tsis kam thiab yooj yim siv 1,2,3.Raws li cov nqi txo, nws tau dhau los ua ntau dua hauv kev siv engineering xws li fiberglass (GFRP), carbon fiber (CFRP), basalt fiber (BFRP), thiab aramid fiber (AFRP), uas yog cov feem ntau siv FRP rau cov qauv kev txhawb zog4, 5. Txoj kev npaj FRP khaws cia tuaj yeem txhim kho kev ua tau zoo thiab tsis txhob tawg ntxov ntxov.Txawm li cas los xij, ntau qhov chaw sab nraud hauv kev tsim kho tshuab feem ntau cuam tshuam rau kev ua haujlwm ntawm FRP-limited pob zeb, ua rau nws lub zog raug cuam tshuam.
Ntau tus kws tshawb fawb tau kawm txog kev ntxhov siab thiab kev hloov pauv hauv cov pob zeb sib txawv nrog cov duab sib txawv thiab qhov ntau thiab tsawg.Yang et al.6 pom tau hais tias qhov kawg ntawm kev ntxhov siab thiab kev nyuaj siab cuam tshuam nrog kev loj hlob ntawm cov ntaub so ntswg tuab.Wu et al.7 tau txais kev ntxhov siab-txheej nkhaus rau FRP-constrained pob zeb siv ntau hom fiber ntau los kwv yees qhov kawg hom kab mob thiab cov khoom thauj.Lin et al.8 pom tias FRP stress-strain qauv rau puag ncig, square, rectangular, thiab elliptical tuav kuj txawv heev, thiab tsim ib tug tshiab tsim-oriented kev nyuaj siab qauv siv qhov ratio ntawm dav thiab kaum vojvoog raws li tsis.Lam et al.9 tau pom tias qhov tsis sib xws ntawm qhov sib tshooj thiab qhov nkhaus ntawm FRP ua rau muaj kev puas tsuaj tsawg thiab kev ntxhov siab hauv FRP ntau dua li cov kev sim slab tensile.Tsis tas li ntawd, cov kws tshawb fawb tau kawm txog qee qhov kev txwv thiab cov kev txwv tshiab raws li kev xav tau ntawm kev tsim lub ntiaj teb sib txawv.Wang et al.[10] tau ua cov kev ntsuam xyuas axial compression ntawm tag nrho, ib nrab thiab tsis txwv cov pob zeb hauv peb hom txwv.Tus qauv "kev ntxhov siab-kev nyuaj siab" tau tsim thiab cov coefficients ntawm kev txwv cov nyhuv rau cov pob zeb kaw ib nrab tau muab.Wu et al.11 tau tsim ib txoj hauv kev los kwv yees qhov kev ntxhov siab-kev vam khom ntawm FRP-constrained pob zeb uas yuav siv rau hauv cov txiaj ntsig loj.Moran et al.12 soj ntsuam cov axial monotonic compression zog ntawm constrained pob zeb nrog FRP helical strips thiab muab tau nws cov kev ntxhov siab-strain curves.Txawm li cas los xij, txoj kev tshawb fawb saum toj no feem ntau tshuaj xyuas qhov sib txawv ntawm ib feem ntawm cov pob zeb thiab cov pob zeb uas muaj tag nrho.Lub luag haujlwm ntawm FRPs qee qhov txwv cov ntu ntu tsis tau kawm kom ntxaws.
Tsis tas li ntawd, txoj kev tshawb fawb tau soj ntsuam qhov kev ua tau zoo ntawm FRP-txhim kho pob zeb nyob rau hauv cov nqe lus ntawm compressive zog, strain hloov, thawj modulus ntawm elasticity, thiab strain-hardening modulus nyob rau hauv ntau yam mob.Tijani et al.13,14 pom tias qhov kev kho ntawm FRP-limited pob zeb txo qis nrog kev puas tsuaj ntxiv hauv FRP kev sim kho ntawm cov pob zeb ua ntej.Ma et al.[15] tau kawm txog cov txiaj ntsig ntawm kev puas tsuaj ntawm FRP-constrained pob zeb txhua kab thiab txiav txim siab tias qhov cuam tshuam ntawm kev puas tsuaj ntawm lub zog tensile yog qhov tsis txaus ntseeg, tab sis muaj kev cuam tshuam loj rau sab nraud thiab ntev deformations.Txawm li cas los xij, Cao et al.16 tau pom qhov kev ntxhov siab-txhim kho qhov nkhaus thiab lub hnab ntawv kev ntxhov siab ntawm FRP-constrained qhob cuam tshuam los ntawm kev puas tsuaj thaum pib.Ntxiv nrog rau cov kev tshawb fawb txog kev ua tsis tiav thawj zaug, qee qhov kev tshawb fawb kuj tau ua tiav ntawm kev ua haujlwm ntawm FRP-limited pob zeb nyob rau hauv ib puag ncig hnyav.Cov kws tshawb fawb no tau kawm txog qhov degradation ntawm FRP-txheej txheem ua vaj tse nyob rau hauv cov xwm txheej hnyav thiab siv cov kev ntsuam xyuas kev puas tsuaj los tsim cov qauv degradation los kwv yees lub neej kev pab cuam.Xie et al.17 muab FRP-constrained pob zeb nyob rau hauv ib puag ncig hydrothermal thiab pom tias hydrothermal tej yam kev mob cuam tshuam rau txhua yam khoom ntawm FRP, uas ua rau nws maj mam txo nws compressive zog.Nyob rau hauv ib puag ncig acid-base, qhov sib cuam tshuam ntawm CFRP thiab pob zeb tsis zoo.Raws li lub sij hawm immersion nce, tus nqi ntawm kev tso tawm ntawm lub zog ntawm kev puas tsuaj ntawm CFRP txheej yuav txo qis, uas thaum kawg ua rau kev puas tsuaj ntawm interfacial qauv 18,19,20.Tsis tas li ntawd, qee cov kws tshawb fawb kuj tau kawm txog qhov cuam tshuam ntawm kev khov thiab thawing ntawm FRP-limited pob zeb.Liu et al.21 tau sau tseg tias CFRP rebar muaj qhov ua tau zoo nyob rau hauv lub voj voog khov-thaw raws li tus txheeb ze dynamic modulus, compressive zog, thiab kev ntxhov siab-strain piv.Tsis tas li ntawd, ib qho qauv yog npaj siab uas cuam tshuam nrog kev ua kom tsis zoo ntawm cov khoom siv dag zog ntawm pob zeb.Txawm li cas los xij, Peng et al.22 suav lub neej ntawm CFRP thiab cov nplaum nplaum uas siv cov ntaub ntawv kub thiab khov-thaw lub voj voog.Guang et al.23 tau ua qhov kev sim khov-thaw sai ntawm cov pob zeb thiab tau npaj ib txoj hauv kev los ntsuas Frost resistance raws li cov thickness ntawm cov txheej puas nyob rau hauv khov-thaw raug.Yazdani et al.24 tau kawm txog cov txiaj ntsig ntawm FRP txheej ntawm kev nkag mus ntawm chloride ions rau hauv pob zeb.Cov txiaj ntsig tau pom tias FRP txheej yog tshuaj tiv thaiv thiab insulates cov pob zeb sab hauv los ntawm cov chloride ions sab nraud.Liu et al.25 simulated tev kuaj tej yam kev mob rau sulfate-corroded FRP pob zeb, tsim ib tug plam qauv, thiab kwv yees degradation ntawm FRP-concrete interface.Wang et al.26 tau tsim cov qauv kev ntxhov siab rau FRP-constrained sulphate-eroded qhob los ntawm kev sim uniaxial compression.Zhou et al.[27] tau kawm txog kev puas tsuaj rau cov pob zeb uas tsis muaj kev sib koom ua ke los ntawm kev sib xyaw kom khov-thaw cycles ntawm ntsev thiab thawj zaug siv lub logistic ua haujlwm los piav qhia txog qhov tsis ua haujlwm.Cov kev tshawb fawb no tau ua tiav qhov tseem ceeb hauv kev ntsuas qhov ua tau ntev ntawm FRP-limited pob zeb.Txawm li cas los xij, feem ntau cov kws tshawb fawb tau tsom mus rau kev ua qauv erosive media nyob rau hauv ib qho xwm txheej tsis zoo.Cov pob zeb feem ntau puas vim yog kev yaig los ntawm ntau yam ib puag ncig.Cov kev sib koom ua ke ib puag ncig no ua rau tsis zoo rau kev ua haujlwm ntawm FRP-txhim kho pob zeb.
Sulfation thiab khov-thaw cycles yog ob qho tseem ceeb tsis zoo uas cuam tshuam rau lub kav ntev ntawm pob zeb.FRP localization technology tuaj yeem txhim kho cov khoom ntawm pob zeb.Nws yog dav siv hauv engineering thiab kev tshawb fawb, tab sis tam sim no muaj nws cov kev txwv.Ntau qhov kev tshawb fawb tau tsom mus rau qhov tsis kam ntawm FRP-txhim kho pob zeb rau sulfate corrosion hauv cov cheeb tsam txias.Cov txheej txheem ntawm erosion ntawm tag nrho cov nyob ib puag ncig, semi-enclosed thiab qhib pob zeb los ntawm sodium sulfate thiab freeze-thaw tsim nyog tau txais kev kawm paub ntau ntxiv, tshwj xeeb tshaj yog cov tshiab semi-enclosed txoj kev piav nyob rau hauv tsab xov xwm no.Qhov kev txhawb zog ntawm cov pob zeb pob zeb kuj tau kawm los ntawm kev sib pauv qhov kev txiav txim ntawm FRP tuav thiab yaig.Microcosmic thiab macroscopic hloov pauv hauv cov qauv tshwm sim los ntawm daim ntawv cog lus yaig tau pom los ntawm electron microscope, pH test, SEM electron microscope, EMF zog spectrum tsom xam thiab uniaxial mechanical test.Tsis tas li ntawd, txoj kev tshawb no tham txog cov cai tswj kev ntxhov siab-kev sib raug zoo uas tshwm sim hauv uniaxial mechanical testing.Qhov kev sim tshuaj ntsuam xyuas qhov kev txwv kev ntxhov siab thiab cov txiaj ntsig zoo tau raug lees paub los ntawm kev txheeb xyuas qhov yuam kev siv plaub tus qauv txwv kev ntxhov siab uas twb muaj lawm.Cov qauv npaj tau tuaj yeem kwv yees qhov kawg ntawm qhov kawg thiab lub zog ntawm cov khoom siv, uas yog qhov tseem ceeb rau yav tom ntej FRP kev siv dag zog.Thaum kawg, nws yog lub hauv paus ntsiab lus rau FRP pob zeb ntsev Frost tsis kam lub tswv yim.
Txoj kev tshawb no ntsuas qhov tsis zoo ntawm FRP-limited pob zeb siv sulfate tov corrosion ua ke nrog khov-thaw mus.Microscopic thiab macroscopic hloov pauv tshwm sim los ntawm cov pob zeb yaig tau tshwm sim los ntawm kev siv tshuaj ntsuam xyuas electron microscopy, pH kuaj, EDS zog spectroscopy, thiab uniaxial mechanical testing.Tsis tas li ntawd, cov khoom siv kho tshuab thiab kev ntxhov siab hloov pauv ntawm FRP-constrained pob zeb raug kev sib raug zoo nrog kev yaig tau tshawb xyuas siv cov kev sim axial compression.
FRP Confined Concrete muaj cov pob zeb nyoos, FRP txheej qhwv thiab epoxy nplaum.Ob qho khoom siv rwb thaiv tsev sab nraud raug xaiv: CFRP thiab GRP, cov khoom ntawm cov ntaub ntawv tau qhia hauv Table 1. Epoxy resins A thiab B tau siv los ua cov nplaum (sib piv 2: 1 los ntawm ntim).Rice.1 piav qhia cov ntsiab lus ntawm kev tsim cov khoom sib xyaw ua ke.Hauv daim duab 1a, Swan PO 42.5 Portland cement tau siv.Coarse aggregates yog crushed pob zeb basalt nrog ib txoj kab uas hla ntawm 5-10 thiab 10-19 mm, ntsig txog, raws li qhia hauv daim duab.1 ib c.Raws li ib tug zoo muab tub lim nyob rau hauv daim duab. 1g siv ntuj dej xuab zeb nrog ib tug fineness modulus ntawm 2.3.Npaj ib qho kev daws ntawm sodium sulfate los ntawm granules ntawm anhydrous sodium sulfate thiab ib tug npaum li cas ntawm cov dej.
Qhov sib xyaw ntawm cov pob zeb sib xyaw: a - cement, b - aggregate 5-10 mm, c - aggregate 10-19 mm, d - dej xuab zeb.
Lub zog tsim ntawm pob zeb yog 30 MPa, uas ua rau cov cement pob zeb tshiab ntawm 40 mus rau 100 hli.Qhov sib xyaw ua ke yog qhia nyob rau hauv Table 2, thiab qhov sib piv ntawm ntxhib aggregate 5-10 mm thiab 10-20 mm yog 3: 7.Cov txiaj ntsig ntawm kev sib cuam tshuam nrog ib puag ncig tau ua qauv los ntawm thawj zaug npaj cov tshuaj 10% NaSO4 thiab tom qab ntawd nchuav cov tshuaj mus rau hauv chav dej khov-thaw lub voj voog.
Kev sib xyaw ua ke tau npaj rau hauv 0.5 m3 yuam kev sib tov thiab tag nrho cov pob zeb ua tau siv los tso cov qauv xav tau.Ua ntej tshaj plaws, cov khoom xyaw pob zeb tau npaj raws li Table 2, thiab cov cement, xuab zeb thiab coarse aggregate yog premixed rau peb feeb.Tom qab ntawd tusyees faib cov dej thiab do rau 5 feeb.Tom ntej no, cov qauv pob zeb tau muab pov rau hauv cov pwm cylindrical thiab compacted ntawm lub rooj vibrating (pwm txoj kab uas hla 10 cm, qhov siab 20 cm).
Tom qab kho rau 28 hnub, cov qauv tau muab qhwv nrog cov khoom FRP.Txoj kev tshawb no tham txog peb txoj hauv kev rau cov pob zeb uas muaj zog ntxiv, suav nrog kev kaw tag nrho, ib nrab txwv, thiab tsis txwv.Ob hom, CFRP thiab GFRP, yog siv rau cov khoom siv tsawg.FRP Tag Nrho FRP pob zeb plhaub, 20 cm siab thiab 39 cm ntev.Sab saum toj thiab hauv qab ntawm FRP-bound pob zeb tsis tau ntim nrog epoxy.Cov txheej txheem kuaj ib nrab-hermetic raws li qhov tsis ntev los no tau pom zoo airtight technology tau piav qhia hauv qab no.
(2) Siv tus pas ntsuas, kos ib kab ntawm lub pob zeb cylindrical nto los txiav txim siab txoj hauj lwm ntawm FRP strips, qhov kev ncua deb ntawm cov strips yog 2.5 cm.Tom qab ntawd qhwv daim kab xev nyob ib ncig ntawm thaj chaw pob zeb uas tsis xav tau FRP.
(3) Lub pob zeb nto yog polished du nrog cov ntawv xuab zeb, so nrog cawv wool, thiab coated nrog epoxy.Tom qab ntawd manually lo cov fiberglass strips mus rau lub pob zeb nto thiab nias tawm qhov khoob kom lub fiberglass tag nrho adherent rau lub pob zeb nto thiab tsis txhob muaj cua npuas.Thaum kawg, muab cov FRP strips rau ntawm cov pob zeb saum npoo ntawm sab saum toj mus rau hauv qab, raws li cov cim ua nrog tus pas ntsuas.
(4) Tom qab ib nrab teev, xyuas seb lub pob zeb puas tau sib cais los ntawm FRP.Yog tias FRP plam lossis tawm, nws yuav tsum tau kho tam sim ntawd.Cov pwm pwm yuav tsum tau kho rau 7 hnub kom kho tau lub zog.
(5) Tom qab kho, siv cov riam siv hluav taws xob tshem tawm cov kab xev los ntawm cov pob zeb ua pob zeb, thiab thaum kawg tau txais ib kab ntawv semi-hermetic FRP pob zeb.
Cov txiaj ntsig nyob rau hauv ntau yam kev txwv yog qhia hauv daim duab.2. Daim duab 2a qhia txog lub pob zeb uas muaj CFRP tag nrho, Daim duab 2b qhia tau hais tias ib qho kev sib koom ua ke ntawm CFRP pob zeb, Daim duab 2c qhia tau hais tias muaj ib qho GFRP cov pob zeb uas muaj tag nrho, thiab daim duab 2d qhia tau hais tias ib qho CFRP pob zeb ib nrab.
Cov qauv uas nyob ib puag ncig: (a) tag nrho CFRP;(b) semi-kaw carbon fiber ntau;(c) tag nrho nyob rau hauv fiberglass;(d) semi-enclosed fiberglass.
Muaj plaub qhov tsis tseem ceeb uas tau tsim los tshawb xyuas qhov cuam tshuam ntawm FRP txwv thiab kev yaig ib ntus ntawm kev yaig tswj kev ua haujlwm ntawm lub tog raj kheej.Table 3 qhia cov naj npawb ntawm cov qauv kab ke.Cov qauv rau txhua pawg muaj peb qhov qauv zoo tib yam kom cov ntaub ntawv sib xws.Qhov nruab nrab ntawm peb cov qauv tau txheeb xyuas rau txhua qhov kev sim ua tiav hauv kab lus no.
(1) Cov khoom siv airtight yog cais raws li carbon fiber lossis fiberglass.Ib qho kev sib piv tau ua los ntawm cov nyhuv ntawm ob hom fibers ntawm lub zog ntawm cov pob zeb.
(2) Txoj kev ntim cov pob zeb yog muab faib ua peb hom: tag nrho txwv, ib nrab txwv thiab tsis txwv.Kev yaig tsis kam ntawm cov pob zeb semi-cuam tshuam tau muab piv nrog rau ob qho lwm yam.
(3) Cov txheej txheem yaig yog lub voj voog khov-thaw ntxiv ntxiv rau cov tshuaj sulfate, thiab cov voj voog khov-thaw yog 0, 50 thiab 100 zaug, feem.Cov txiaj ntsig ntawm kev sib txuas ua ke ntawm FRP-constrained pob zeb kem tau kawm.
(4) Cov ntawv xeem tau muab faib ua peb pawg.Thawj pab pawg yog FRP wrapping thiab tom qab ntawd corrosion, pawg thib ob yog corrosion ua ntej thiab tom qab ntawd qhwv, thiab peb pawg yog corrosion ua ntej thiab tom qab ntawd qhwv thiab tom qab ntawd corrosion.
Cov txheej txheem kev sim siv lub tshuab ntsuas thoob ntiaj teb, lub tshuab ntsuas tensile, lub voj voog khov-thaw (CDR-Z hom), lub tshuab ntsuas hluav taws xob, lub ntsuas pH, lub ntsuas ntsuas, lub tshuab xa tawm, SEM electron microscope, thiab ib qho EDS lub zog spectrum analyzer hauv txoj kev tshawb no.Cov qauv yog ib qho pob zeb 10 cm siab thiab 20 cm inch.Cov pob zeb tau kho tsis pub dhau 28 hnub tom qab pouring thiab compaction, raws li qhia hauv daim duab 3a.Tag nrho cov qauv raug demoulded tom qab casting thiab khaws cia rau 28 hnub ntawm 18-22 ° C thiab 95% txheeb ze av noo, thiab tom qab ntawd qee cov qauv tau qhwv nrog fiberglass.
Cov txheej txheem xeem: (a) cov cuab yeej siv los tswj qhov kub thiab txias tsis tu ncua;(b) lub tshuab khov-thaw lub voj voog;(c) universal kuaj tshuab;(d) pH tester;(e) Kev soj ntsuam microscopic.
Kev sim khov-thaw siv lub flash freeze txoj kev raws li qhia hauv daim duab 3b.Raws li GB / T 50082-2009 "Durability Standards for Conventional Concrete", cov qauv pob zeb tau muab tso rau hauv 10% sodium sulfate tov ntawm 15-20 ° C rau 4 hnub ua ntej khov thiab thawing.Tom qab ntawd, sulfate nres pib thiab xaus ib txhij nrog lub voj voog khov-thaw.Lub sij hawm khov-thaw lub sij hawm yog 2 mus rau 4 teev, thiab lub sij hawm defrosting yuav tsum tsis txhob tsawg tshaj li 1/4 ntawm lub sij hawm voj voog.Cov qauv ntsuas kub yuav tsum tau khaws cia nyob rau hauv thaj tsam ntawm (-18 ± 2) txog (5 ± 2) ° C.Kev hloov ntawm khov mus rau defrosting yuav tsum tsis pub ntau tshaj kaum feeb.Peb cov qauv cylindrical zoo ib yam ntawm txhua pawg tau siv los kawm txog qhov poob phaus thiab hloov pH ntawm cov tshuaj tshaj 25 lub voj voog khov-thaw, raws li qhia hauv daim duab 3d.Tom qab txhua 25 lub voj voog khov-thaw, cov qauv raug tshem tawm thiab cov chaw ntxuav ua ntej txiav txim siab lawv qhov hnyav (Wd).Txhua qhov kev sim tau ua tiav hauv triplicate ntawm cov qauv, thiab qhov nruab nrab qhov tseem ceeb tau siv los tham txog cov txiaj ntsig kev xeem.Cov qauv rau kev poob ntawm qhov hnyav thiab lub zog ntawm cov qauv yog txiav txim raws li hauv qab no:
Hauv cov qauv, ΔWd yog qhov hnyav poob (%) ntawm cov qauv tom qab txhua txhua 25 lub voj voog khov-thaw, W0 yog qhov nruab nrab qhov hnyav ntawm cov qauv pob zeb ua ntej lub voj voog khov-thaw (kg), Wd yog qhov hnyav nruab nrab.Qhov hnyav ntawm cov qauv tom qab 25 lub voj voog khov-thaw (kg).
Lub zog degradation coefficient ntawm tus qauv yog tus cwj pwm los ntawm Kd, thiab cov qauv kev suav yog raws li hauv qab no:
Hauv cov qauv, ΔKd yog tus nqi ntawm lub zog poob (%) ntawm tus qauv tom qab txhua 50 lub voj voog khov-thaw, f0 yog qhov nruab nrab lub zog ntawm cov qauv ua ntej lub voj voog khov-thaw (MPa), fd yog qhov nruab nrab lub zog ntawm cov qauv ua qauv rau 50 lub voj voog khov-thaw (MPa).
Ntawm daim duab.3c qhia lub tshuab ntsuas compressive rau cov qauv ua vaj tse.Raws li "Standard for Test Methods for the Physical and Mechanical Properties of Concrete" (GBT50081-2019), ib txoj hauv kev rau kev sim cov pob zeb ua kom muaj zog compressive yog txhais.Tus nqi thauj khoom hauv kev ntsuas compression yog 0.5 MPa / s, thiab kev thauj khoom tas mus li thiab ua ntu zus yog siv thoob plaws qhov kev xeem.Cov kev sib raug zoo ntawm kev thauj mus los rau txhua tus qauv raug kaw thaum lub sij hawm ntsuas tshuab.Cov ntsuas ntsuas tau txuas mus rau sab nrauv ntawm cov pob zeb thiab FRP txheej ntawm cov qauv ntsuas axial thiab kab rov tav.Lub xovtooj ntawm tes yog siv rau hauv kev ntsuas tshuab los sau cov kev hloov pauv hauv cov qauv kuaj thaum lub sijhawm ntsuas compression.
Txhua 25 lub voj voog khov-thaw, ib qho piv txwv ntawm cov tshuaj khov-thaw tau muab tshem tawm thiab muab tso rau hauv ib lub thawv.Ntawm daim duab.3d qhia txog kev ntsuas pH ntawm cov qauv tshuaj hauv ib lub thawv.Kev tshuaj xyuas microscopic ntawm qhov chaw thiab ntu ntu ntawm cov qauv hauv qab khov-thaw yog qhia hauv daim duab 3d.Lub xeev ntawm qhov chaw ntawm ntau cov qauv tom qab 50 thiab 100 lub voj voog khov-thaw hauv sulfate tov tau pom nyob rau hauv lub tshuab tsom.Lub microscope siv 400x magnification.Thaum soj ntsuam qhov saum npoo ntawm cov qauv, qhov yaig ntawm FRP txheej thiab txheej txheej ntawm cov pob zeb feem ntau yog pom.Kev soj ntsuam ntawm tus ntoo khaub lig ntawm tus qauv yeej xaiv qhov kev yaig ntawm qhov deb ntawm 5, 10 thiab 15 mm los ntawm txheej txheej.Kev tsim cov khoom siv sulfate thiab lub voj voog khov-thaw yuav tsum tau kuaj ntxiv.Yog li, qhov hloov pauv ntawm cov qauv xaiv tau raug tshuaj xyuas siv lub tshuab ntsuas hluav taws xob ntsuas hluav taws xob (SEM) nruab nrog lub zog dispersive spectrometer (EDS).
Saib xyuas cov qauv saum npoo nrog lub tshuab ntsuas hluav taws xob thiab xaiv 400X magnification.Qhov kev puas tsuaj ntawm qhov chaw nyob rau hauv ib nrab thiab tsis sib koom ua ke GRP pob zeb nyob rau hauv lub voj voog khov-thaw thiab raug sulfates yog siab heev, thaum nyob rau hauv tag nrho cov pob zeb nws yog negligible.Thawj qeb yog hais txog qhov tshwm sim ntawm kev yaig ntawm cov pob zeb dawb ntws los ntawm sodium sulfate thiab los ntawm 0 txog 100 lub voj voog khov-thaw, raws li qhia hauv daim duab 4a.Cov qauv pob zeb uas tsis muaj Frost raug cuam tshuam nrog lub ntsej muag du yam tsis pom cov yam ntxwv.Tom qab 50 erosions, lub pulp thaiv ntawm qhov chaw ib nrab tev tawm, nthuav tawm lub plhaub dawb ntawm lub pulp.Tom qab 100 erosions, lub plhaub ntawm cov kev daws teeb meem kiag li poob tawm thaum lub sij hawm saib xyuas ntawm lub pob zeb nto.Kev soj ntsuam ntawm microscopic pom tias qhov chaw ntawm 0 khov-thaw eroded pob zeb yog du thiab qhov sib sau ua ke thiab mortar nyob hauv tib lub dav hlau.Ib qho tsis sib xws, ntxhib saum npoo tau pom ntawm lub pob zeb ua kom tawg los ntawm 50 lub voj voog khov-thaw.Qhov no tuaj yeem piav qhia los ntawm qhov tseeb tias qee qhov mortar raug rhuav tshem thiab ib qho me me ntawm cov dawb granular crystals adhere rau saum npoo, uas yog tsim los ntawm aggregate, mortar thiab dawb crystals.Tom qab 100 lub voj voog khov-thaw, thaj tsam loj ntawm cov pob zeb dawb tau tshwm sim rau saum npoo ntawm cov pob zeb, thaum tsaus nti coarse aggregate raug rau sab nraud ib puag ncig.Tam sim no, lub pob zeb nto yog feem ntau raug aggregate thiab dawb crystals.
Morphology ntawm erosive freeze-thaw qhob kem: (a) unrestricted pob zeb kem;(b) semi-enclosed carbon fiber reinforced qhob;(c) GRP semi-enclosed pob zeb;(d) tag nrho CFRP pob zeb;(e) GRP pob zeb semi-enclosed pob zeb.
Qhov thib ob yog qhov corrosion ntawm semi-hermetic CFRP thiab GRP pob zeb txhua kab nyob rau hauv khov-thaw cycles thiab raug rau sulfates, raws li qhia nyob rau hauv daim duab 4b, c.Kev soj ntsuam pom (1x magnification) pom tau tias cov hmoov dawb maj mam tsim nyob rau saum npoo ntawm cov txheej fibrous, uas sai sai poob tawm nrog ib qho kev nce hauv cov voj voog khov-thaw.Qhov tsis muaj kev txwv tsis pub yaig ntawm semi-hermetic FRP pob zeb tau dhau los ua kom pom ntau dua vim tias cov voj voog khov-thaw tau nce.Qhov tshwm sim pom ntawm "bloating" (qhov qhib ntawm qhov kev daws teeb meem ntawm cov pob zeb pob zeb yog nyob rau ntawm lub verge ntawm lub cev qhuav dej).Txawm li cas los xij, qhov tshwm sim ntawm tev tawm yog ib feem cuam tshuam los ntawm cov txheej txheem carbon fiber uas nyob ib sab).Nyob rau hauv lub microscope, hluavtaws carbon fibers tshwm li cov xov dawb ntawm keeb kwm dub ntawm 400x magnification.Vim lub puag ncig ntawm cov fibers thiab raug rau lub teeb tsis sib xws, lawv tshwm dawb, tab sis cov carbon fiber bundles lawv tus kheej yog dub.Fiberglass yog pib dawb xov zoo li, tab sis thaum sib cuag nrog cov nplaum nws ua pob tshab thiab lub xeev ntawm cov pob zeb hauv lub fiberglass yog pom meej.Lub fiberglass yog ci dawb thiab lub binder yog yellowish.Ob leeg yog xim xim heev, yog li cov xim ntawm cov kua nplaum yuav nkaum cov fiberglass strands, muab tag nrho cov xim daj.Cov pa roj carbon thiab iav fibers yog tiv thaiv los ntawm kev puas tsuaj los ntawm lwm yam epoxy resin.Raws li tus naj npawb ntawm khov-thaw tawm tsam tau nce, ntau qhov khoob thiab ob peb lub ntsej muag dawb tau pom ntawm qhov chaw.Raws li lub voj voog ntawm sulfate freezing nce, cov binder maj mam ua nyias, cov xim daj ploj thiab cov fibers pom.
Qhov thib peb qeb yog qhov corrosion ntawm tag nrho cov CFRP thiab GRP pob zeb nyob rau hauv lub freeze-thaw cycles thiab raug rau sulfates, raws li qhia nyob rau hauv daim duab 4d, e.Ntxiv dua thiab, cov txiaj ntsig tau pom zoo ib yam li cov rau hom thib ob ntawm ntu ntu ntawm cov pob zeb pob zeb.
Sib piv cov phenomena pom tom qab siv peb txoj kev tuav pov hwm tau piav qhia saum toj no.Cov ntaub so ntswg nyob rau hauv tag nrho insulated FRP pob zeb nyob ruaj khov raws li tus naj npawb ntawm khov-thaw cycles nce.Ntawm qhov tod tes, cov nplaum nplaum txheej txheej yog thinner rau ntawm qhov chaw.Epoxy resins feem ntau hnov ​​​​mob nrog active hydrogen ions nyob rau hauv qhib-ring sulfuric acid thiab tsis tshua muaj tshwm sim nrog sulfates28.Yog li, nws tuaj yeem txiav txim siab tias kev yaig feem ntau hloov cov khoom ntawm cov nplaum nplaum raws li qhov tshwm sim ntawm cov voj voog khov-thaw, yog li hloov cov nyhuv ntawm FRP.Lub pob zeb nto ntawm FRP semi-hermetic pob zeb muaj qhov tshwm sim zoo ib yam li cov pob zeb tsis muaj kev txwv.Nws FRP txheej sib raug rau FRP txheej ntawm tag nrho cov pob zeb, thiab qhov kev puas tsuaj tsis pom tseeb.Txawm li cas los xij, nyob rau hauv semi-sealed GRP pob zeb, qhov tawg loj heev tshwm sim qhov twg cov fiber ntau cuam tshuam nrog cov pob zeb tawg.Kev yaig ntawm cov pob zeb uas raug pom ua rau hnyav dua vim tias cov voj voog khov-thaw nce ntxiv.
Lub sab hauv ntawm tag nrho ntim, ib nrab-pob zeb, thiab tsis muaj kev txwv FRP pob zeb pom qhov sib txawv tseem ceeb thaum raug rau lub voj voog khov-thaw thiab raug cov tshuaj sulfate.Cov qauv raug txiav transversely thiab hla ntu tau pom siv lub tshuab ntsuas hluav taws xob ntawm 400x magnification.Ntawm daim duab.5 qhia cov duab microscopic ntawm qhov deb ntawm 5 mm, 10 mm thiab 15 mm los ntawm ciam teb ntawm pob zeb thiab mortar, feem.Nws tau raug pom tias thaum cov tshuaj sodium sulfate ua ke nrog khov-thaw, kev puas tsuaj ua pob zeb tau tawg zuj zus los ntawm qhov chaw mus rau sab hauv.Vim tias qhov kev yaig sab hauv ntawm CFRP thiab GFRP-constrained pob zeb yog tib yam, ntu no tsis sib piv ob cov khoom ntim khoom.
Kev soj ntsuam me me ntawm sab hauv ntawm cov pob zeb ntawm cov kab ke: (a) txwv tag nrho los ntawm fiberglass;(b) semi-pob nrog fiberglass;(c) unlimited.
Internal erosion ntawm FRP tag nrho cov pob zeb uas muaj nyob rau hauv daim duab.5 ib a.Cov kab nrib pleb yog pom ntawm 5 hli, qhov saum npoo yog du, tsis muaj crystallization.Qhov saum npoo yog du, tsis muaj crystal, 10 mus rau 15 mm tuab.Internal yaig ntawm FRP semi-hermetic pob zeb yog qhia nyob rau hauv daim duab.5 B. Cov kab nrib pleb thiab cov pob zeb dawb pom ntawm 5 hli thiab 10 hli, thiab qhov saum npoo yog du ntawm 15 hli.Daim duab 5c qhia txog ntu ntawm pob zeb FRP kab uas muaj kab nrib pleb ntawm 5, 10 thiab 15 hli.Ob peb lub pob zeb dawb hauv cov kab nrib pleb tau dhau los ua qhov tsis tshua muaj vim cov kab nrib pleb txav ntawm sab nraud ntawm cov pob zeb mus rau sab hauv.Cov pob zeb uas tsis muaj qhov kawg tau pom tias muaj kev yaig ntau tshaj plaws, ua raws li cov pob zeb semi-constrained FRP.Sodium sulfate muaj qhov cuam tshuam me ntsis rau sab hauv ntawm tag nrho cov FRP pob zeb ua piv txwv tshaj 100 lub voj voog khov-thaw.Qhov no qhia tau hais tias lub ntsiab ua rau yaig ntawm tag nrho constrained FRP pob zeb yog txuam nrog khov-thaw erosion nyob rau ib lub sij hawm.Kev soj ntsuam ntawm ntu ntu ntu tau pom tias ntu tam sim ua ntej khov thiab thawing yog du thiab tsis muaj cov khoom sib xyaw.Raws li cov pob zeb khov thiab thaws, cov kab nrib pleb pom, tib yam yog qhov tseeb rau kev sib sau ua ke, thiab cov pob zeb dawb granular yog ntom ntom nrog cov kab nrib pleb.Studies27 tau pom tias thaum cov pob zeb muab tso rau hauv cov tshuaj sodium sulfate, sodium sulfate yuav nkag mus rau hauv cov pob zeb, qee qhov yuav los nag ua cov pob zeb sodium sulfate, thiab qee qhov yuav ua rau cov cement.Sodium sulfate crystals thiab cov khoom siv tshuaj tiv thaiv zoo li cov granules dawb.
FRP txwv tag nrho cov pob zeb tawg nyob rau hauv conjugated yaig, tab sis cov seem yog du yam tsis muaj crystallization.Ntawm qhov tod tes, FRP ib nrab kaw thiab tsis txwv cov pob zeb ua ke tau tsim cov kab nrib pleb thiab crystallization nyob rau hauv conjugated yaig.Raws li cov lus piav qhia ntawm daim duab thiab cov kev tshawb fawb yav dhau los29, kev sib koom ua ke ntawm cov txheej txheem ntawm kev tsis muaj kev txwv thiab ib nrab txwv FRP pob zeb tau muab faib ua ob theem.Thawj theem ntawm pob zeb tawg yog txuam nrog kev nthuav dav thiab kev cog lus thaum khov-thaw.Thaum cov sulphate nkag mus rau hauv cov pob zeb thiab pom, cov sulphate sib xyaw ua ke cov kab nrib pleb tsim los ntawm kev shrinkage los ntawm khov-thaw thiab dej tshuaj tiv thaiv.Yog li ntawd, sulfate muaj kev tiv thaiv tshwj xeeb ntawm cov pob zeb thaum ntxov thiab tuaj yeem txhim kho cov khoom ntawm pob zeb rau qee yam.Qhov thib ob theem ntawm sulfate nres txuas ntxiv mus, nkag mus rau cov kab nrib pleb lossis voids thiab reacting nrog cov cement los tsim alum.Yog li ntawd, cov kab nrib pleb loj hlob tuaj thiab ua rau kev puas tsuaj.Nyob rau lub sijhawm no, kev nthuav dav thiab kev cog lus cuam tshuam nrog kev khov thiab thawing yuav ua rau muaj kev puas tsuaj sab hauv rau cov pob zeb, uas ua rau txo qis ntawm cov kabmob.
Ntawm daim duab.6 qhia txog kev hloov pauv pH ntawm cov kev daws teeb meem ntawm cov pob zeb impregnation rau peb txoj kev txwv kev soj ntsuam tom qab 0, 25, 50, 75, thiab 100 lub voj voog khov-thaw.Unrestricted thiab semi-kaw FRP pob zeb mortars pom qhov ceev tshaj pH nce ntawm 0 mus rau 25 lub voj voog khov-thaw.Lawv pH qhov tseem ceeb tau nce los ntawm 7.5 mus rau 11.5 thiab 11.4, feem.Raws li tus naj npawb ntawm cov voj voog khov-thaw tau nce, pH nce maj mam qeeb tom qab 25-100 lub voj voog khov-thaw.Lawv pH qhov tseem ceeb tau nce los ntawm 11.5 thiab 11.4 mus rau 12.4 thiab 11.84, feem.Vim tias qhov sib koom ua ke FRP tag nrho npog FRP txheej, nws nyuaj rau kev daws cov tshuaj sodium sulfate kom nkag mus.Nyob rau tib lub sijhawm, nws yog qhov nyuaj rau cov cement muaj pes tsawg leeg nkag mus rau hauv cov kev daws teeb meem sab nraud.Yog li, pH maj mam nce ntawm 7.5 mus rau 8.0 ntawm 0 thiab 100 lub voj voog khov-thaw.Yog vim li cas rau qhov hloov ntawm pH yog soj ntsuam raws li hauv qab no.Cov silicate hauv pob zeb ua ke nrog hydrogen ions hauv dej los ua silicic acid, thiab cov OH uas tseem tshuav - nce pH ntawm cov tshuaj saturated.Qhov kev hloov pauv hauv pH tau tshaj tawm ntawm 0-25 lub voj voog khov-thaw thiab qis dua ntawm 25-100 lub voj voog khov-thaw 30.Txawm li cas los xij, nws tau pom ntawm no tias pH txuas ntxiv nce tom qab 25-100 lub voj voog khov-thaw.Qhov no tuaj yeem piav qhia los ntawm qhov tseeb tias sodium sulfate reacts chemically nrog rau sab hauv ntawm cov pob zeb, hloov pH ntawm cov tshuaj.Kev tshuaj xyuas ntawm cov tshuaj muaj pes tsawg leeg qhia tau hais tias cov pob zeb ua haujlwm nrog sodium sulfate raws li hauv qab no.
Formulas (3) thiab (4) qhia tau hais tias sodium sulfate thiab calcium hydroxide nyob rau hauv cement daim ntawv gypsum (calcium sulfate), thiab calcium sulfate ntxiv reacts nrog calcium metaaluminate nyob rau hauv cement los tsim alum crystals.Cov tshuaj tiv thaiv (4) yog nrog los ntawm kev tsim ntawm OH-, uas ua rau nce pH.Tsis tas li ntawd, txij li cov tshuaj tiv thaiv no thim rov qab, pH nce ntawm ib lub sijhawm thiab hloov maj mam.
Ntawm daim duab.7a qhia tau hais tias qhov poob phaus ntawm tag nrho cov nyob rau hauv, ib nrab-cuam tshuam, thiab interlocked GRP pob zeb thaum lub sij hawm khov-thaw cycles nyob rau hauv sulfate tov.Qhov pom tseeb tshaj plaws kev hloov pauv hauv huab hwm coj poob yog qhov tsis muaj kev txwv tsis pub muaj.Cov pob zeb tsis txwv tsis pub poob txog 3.2% ntawm nws qhov loj tom qab 50 qhov kev tawm tsam khov-thaw thiab txog 3.85% tom qab 100 khov-thaw tawm tsam.Cov txiaj ntsig tau pom tias cov txiaj ntsig ntawm kev sib xyaw ua kom yaig ntawm qhov zoo ntawm cov pob zeb dawb-kho tau txo qis thaum lub voj voog khov-thaw nce.Txawm li cas los xij, thaum soj ntsuam qhov saum npoo ntawm cov qauv, nws tau pom tias qhov poob ntawm mortar tom qab 100 lub voj voog khov-thaw yog ntau dua tom qab 50 lub voj voog khov-thaw.Ua ke nrog cov kev tshawb fawb hauv ntu yav dhau los, nws tuaj yeem xav tias kev nkag mus ntawm sulfates rau hauv pob zeb ua rau muaj kev poob qis hauv kev poob qis.Lub caij no, sab hauv tsim cov alum thiab gypsum kuj ua rau poob qis, raws li kev kwv yees los ntawm kev sib npaug tshuaj (3) thiab (4).
Qhov hnyav hloov pauv: (a) kev sib raug zoo ntawm qhov hnyav hloov pauv thiab cov voj voog khov-thaw;(b) kev sib raug zoo ntawm huab hwm coj hloov pauv thiab tus nqi pH.
Kev hloov pauv hauv qhov hnyav ntawm FRP semi-hermetic pob zeb ua ntej txo qis thiab tom qab ntawd nce.Tom qab 50 lub voj voog khov-thaw, qhov poob ntawm ib nrab-hermetic fiberglass pob zeb yog li 1.3%.Qhov hnyav poob tom qab 100 lub voj voog yog 0.8%.Yog li ntawd, nws tuaj yeem txiav txim siab tias sodium sulfate nkag mus rau hauv cov pob zeb dawb ntws.Tsis tas li ntawd, kev soj ntsuam ntawm qhov saum npoo ntawm daim ntawv xeem kuj pom tau tias cov fiber ntau strips tuaj yeem tiv taus mortar tev nyob rau hauv qhov chaw qhib, yog li txo qhov hnyav.
Kev hloov pauv hauv huab hwm coj poob ntawm tag nrho FRP pob zeb sib txawv ntawm thawj ob.Pawg tsis poob, tab sis ntxiv.Tom qab 50 Frost-thaw erosions, qhov loj tau nce li ntawm 0.08%.Tom qab 100 lub sij hawm, nws qhov hnyav nce li ntawm 0.428%.Txij li thaum lub pob zeb tau nchuav tag lawm, cov mortar ntawm lub pob zeb yuav tsis tawm thiab tsis zoo li yuav ua rau poob zoo.Ntawm qhov tod tes, kev nkag mus ntawm cov dej thiab sulfates los ntawm cov ntsiab lus siab saum npoo mus rau sab hauv ntawm cov ntsiab lus qis kuj tseem txhim kho qhov zoo ntawm cov pob zeb.
Ntau qhov kev tshawb fawb yav dhau los tau ua los ntawm kev sib raug zoo ntawm pH thiab kev poob loj hauv FRP-txhim kho pob zeb nyob rau hauv erosive tej yam kev mob.Feem ntau ntawm kev tshawb fawb feem ntau tham txog kev sib raug zoo ntawm huab hwm coj poob, elastic modulus thiab lub zog poob.Ntawm daim duab.7b qhia txog kev sib raug zoo ntawm cov pob zeb pH thiab qhov poob loj hauv peb qhov kev txwv.Tus qauv kev kwv yees tau npaj los kwv yees qhov kev poob qis uas siv peb txoj hauv kev khaws cia ntawm qhov sib txawv pH.Raws li tuaj yeem pom hauv daim duab 7b, Pearson tus coefficient yog siab, qhia tias muaj tseeb muaj kev sib raug zoo ntawm pH thiab huab hwm coj poob.r-squared qhov tseem ceeb rau unrestricted, semi-restricted, thiab tag nrho txwv cov pob zeb yog 0.86, 0.75, thiab 0.96, feem.Qhov no qhia tau hais tias pH hloov thiab poob phaus ntawm tag nrho cov insulated qhob yog cov linear nyob rau hauv ob qho tib si sulfate thiab khov-thaw tej yam kev mob.Hauv cov pob zeb uas tsis muaj kev txwv thiab semi-hermetic FRP pob zeb, pH maj mam nce ntxiv thaum cov cement reacts nrog cov tshuaj aqueous.Yog li ntawd, lub pob zeb nto yog maj mam rhuav tshem, uas ua rau muaj qhov hnyav.Ntawm qhov tod tes, pH ntawm tag nrho cov pob zeb ua kom hloov pauv me ntsis vim tias FRP txheej qeeb cov tshuaj tiv thaiv ntawm cov cement nrog cov dej tov.Yog li, rau lub pob zeb uas muaj tag nrho, tsis muaj qhov pom ntawm qhov yaig, tab sis nws yuav nce qhov hnyav vim qhov saturation vim kev nqus ntawm sulfate daws.
Ntawm daim duab.8 qhia cov txiaj ntsig ntawm SEM scan ntawm cov qauv etched nrog sodium sulfate khov-thaw.Electron microscopy soj ntsuam cov qauv sau los ntawm cov blocks coj los ntawm txheej txheej ntawm pob zeb.Daim duab 8a yog ib qho scanning electron microscope duab ntawm unenclosed pob zeb ua ntej yaig.Nws tau raug sau tseg tias muaj ntau qhov nyob rau saum npoo ntawm cov qauv, uas cuam tshuam rau lub zog ntawm cov pob zeb pob zeb nws tus kheej ua ntej Frost-thawing.Ntawm daim duab.8b qhia txog cov duab hluav taws xob hauv tshuab hluav taws xob ntawm cov khoom siv hluav taws xob tag nrho FRP cov qauv tom qab 100 lub voj voog khov-thaw.Cov kab nrib pleb hauv cov qauv vim yog khov thiab thawing tuaj yeem kuaj pom.Txawm li cas los xij, qhov saum npoo yog tus du thiab tsis muaj cov muaju ntawm nws.Yog li ntawd, cov kab nrib pleb uas tsis tau ntim tau pom ntau dua.Ntawm daim duab.8c qhia tau hais tias ib qho piv txwv ntawm semi-hermetic GRP pob zeb tom qab 100 Frost erosion cycles.Nws yog qhov tseeb tias cov kab nrib pleb nthuav dav thiab cov nplej tsim ntawm cov kab nrib pleb.Qee qhov ntawm cov khoom no txuas lawv tus kheej rau cov kab nrib pleb.Ib qho SEM scan ntawm ib qho piv txwv ntawm cov pob zeb tsis muaj kev txwv tsis pub muaj nyob hauv daim duab 8d, qhov tshwm sim zoo ib yam nrog kev txwv ib nrab.Txhawm rau kom paub meej qhov sib xyaw ntawm cov khoom, cov khoom hauv cov kab nrib pleb tau nthuav dav ntxiv thiab tshuaj xyuas siv EDS spectroscopy.Particles yeej tuaj hauv peb qhov sib txawv.Raws li lub zog spectrum tsom xam, thawj hom, raws li qhia nyob rau hauv daim duab 9a, yog ib tug niaj hnub block siv lead ua, feem ntau yog tsim los ntawm O, S, Ca thiab lwm yam.Los ntawm kev sib txuas cov qauv yav dhau los (3) thiab (4), nws tuaj yeem txiav txim siab tias lub ntsiab ntawm cov khoom yog gypsum (calcium sulfate).Qhov thib ob yog qhia hauv daim duab 9b;Raws li lub zog spectrum tsom xam, nws yog ib qho acicular non-directional khoom, thiab nws lub ntsiab Cheebtsam yog O, Al, S thiab Ca.Cov zaub mov sib xyaw ua ke qhia tias cov khoom siv feem ntau yog alum.Qhov thib peb block qhia nyob rau hauv daim duab 9c, yog ib tug irregular block, txiav txim siab los ntawm lub zog spectrum tsom xam, feem ntau muaj cov Cheebtsam O, Na thiab S. Nws muab tawm hais tias cov no mas yog sodium sulfate crystals.Kev soj ntsuam electron microscopy pom tias feem ntau ntawm cov voids tau ntim nrog sodium sulfate crystals, raws li qhia hauv daim duab 9c, nrog rau me me ntawm gypsum thiab alum.
Electron microscopic dluab ntawm cov qauv ua ntej thiab tom qab corrosion: (a) qhib pob zeb ua ntej corrosion;(b) tom qab corrosion, lub fiberglass yog kaw tag;(c) tom qab corrosion ntawm GRP semi-enclosed qhob;(d) tom qab corrosion ntawm qhib pob zeb.
Kev tshuaj ntsuam tso cai rau peb kos cov lus xaus hauv qab no.Cov duab electron microscope ntawm peb cov qauv yog tag nrho 1k × thiab cov khoom tawg thiab yaig tau pom thiab pom hauv cov duab.Cov pob zeb uas tsis muaj kev txwv muaj cov kab nrib pleb loj tshaj plaws thiab muaj ntau cov nplej.FRP semi-pressure qhob yog qhov qis dua rau cov pob zeb uas tsis muaj zog nyob rau hauv cov nqe lus ntawm tawg dav thiab particle suav.Tag Nrho FRP pob zeb muaj qhov tsawg tshaj plaws tawg dav thiab tsis muaj cov khoom tom qab khov-thaw yaig.Tag nrho cov no qhia tau hais tias tag nrho FRP pob zeb yog qhov tsawg tshaj plaws rau kev yaig los ntawm khov thiab thaw.Cov txheej txheem tshuaj nyob rau hauv ib nrab-pob thiab qhib FRP pob zeb txhua kab ua rau tsim cov alum thiab gypsum, thiab sulfate nkag mus rau porosity.Thaum lub voj voog khov-thaw yog lub ntsiab ua rau pob zeb tawg, sulfates thiab lawv cov khoom ua rau qee qhov kab nrib pleb thiab qhov hws hauv thawj qhov chaw.Txawm li cas los xij, raws li tus nqi thiab lub sijhawm yaig nce ntxiv, cov kab nrib pleb txuas ntxiv nthuav dav thiab qhov ntim ntawm alum tsim nce, uas ua rau extrusion tawg.Thaum kawg, khov-thaw thiab sulfate raug yuav txo tau lub zog ntawm kem.