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A na-ahụta ihe nrụpụta polymer (FRP) dị ka ụzọ ọhụrụ na nke akụ na ụba nke nrụzi nhazi.N'ime ọmụmụ ihe a, ahọpụtara ihe abụọ a na-ahụkarị [carbon fiber enhanced polymer (CFRP) na glass fiber enhanced polymer (GFRP)] iji mụọ mmetụta na-agba ume nke kọnkịtị na gburugburu ebe siri ike.Atụlela nguzogide nke ihe nwere FRP na mwakpo sulfate yana usoro nhịkọ oyi emetụtara.Electron microscope iji mụọ elu na mmebi nke ime ihe n'oge mbuze jikọtara ọnụ.A na-enyocha ogo na usoro nke corrosion sodium sulfate site na uru pH, microscopy electron SEM, na EMF ume spectrum.Ejila ule mkpakọ nke axial iji nyochaa nkwado nke kọlụm kọlụm FRP na-akpachi anya, yana mmekọrịta nrụgide ka ewepụtarala maka ụzọ dị iche iche nke njide FRP na gburugburu ebe jikọtara ọnụ.Emere nyocha mperi iji mezie nsonaazụ nnwale site na iji ụdị amụma anọ dị ugbu a.Nlebanya niile na-egosi na usoro nbibi nke ihe mgbochi FRP dị mgbagwoju anya ma dị ike n'okpuru nrụgide conjugate.Sodium sulfate na mbụ na-abawanye ike nke kọnkịrị n'ụdị ya.Otú ọ dị, okirikiri ifriizi na-esote nwere ike ime ka mgbawa kọnkịrị ka njọ, sodium sulfate na-ebelatakwa ike nke kọnkịtị site n'ịkwalite mgbawa.A na-atụpụta ụdị ọnụọgụgụ ziri ezi iji mee ka mmekọrịta nke nrụgide nrụgide, nke dị oke mkpa maka imepụta na ịtụle usoro ndụ nke ihe mgbochi FRP.
Dị ka ihe ọhụrụ ihe mkwado usoro nke a nyochaworo kemgbe 1970s, FRP nwere uru nke ìhè arọ, elu ike, corrosion iguzogide, ike ọgwụgwụ na-adaba adaba ewu1,2,3.Ka ọnụ ahịa na-ebelata, ọ na-aghọwanye ihe na ngwa injinia dị ka fiberglass (GFRP), carbon fiber (CFRP), basalt fiber (BFRP), na fiber aramid (AFRP), nke bụ FRP a na-ejikarị eme ihe maka nkwado nhazi4, 5 Usoro njigide FRP nke a tụrụ atụ nwere ike melite arụmọrụ nke ọma ma zere ndakpọ oge.Agbanyeghị, mpaghara dị iche iche dị na mpụga na injinia na-emetụtakarị ịdịte aka nke kọmpụta nwere oke FRP, na-eme ka ike ya ghara imebi.
Ọtụtụ ndị na-eme nchọpụta amụwo mgbakasị ahụ na mgbanwe nhụsianya na kọmpụta nwere ụdị na nha nke akụkụ dị iche iche.Yang et al.6 chọpụtara na nrụgide ikpeazụ na nsogbu jikọtara nke ọma na uto na ọkpụrụkpụ anụ ahụ fibrous.Wu et al.7 nwetara mgbakasị mgbakasị ahụ maka ihe mgbochi FRP na-eji ụdị eriri dị iche iche na-ebu amụma oke na ibu.Lin et al.8 chọpụtara na ụdị nrụgide FRP maka gburugburu, square, rectangular, and elliptical bar dịkwa iche nke ukwuu, wee mepụta ụdị nrụgide nrụgide nrụgide ọhụrụ na-eji oke nke obosara na radius nkuku dị ka paramita.Lam et al.9 kwuru na nkwekọ na-adịghị n'ụdị na mwepu nke FRP butere obere mgbaji mgbaji na nrụgide na FRP karịa n'ule slab tensile.Na mgbakwunye, ndị ọkà mmụta sayensị amụwo ihe mgbochi akụkụ na ụzọ mgbochi ọhụrụ dịka mkpa dị iche iche dị n'ezie nke ụwa si dị.Wang et al.[10] mere ule mkpakọ axial n'ụzọ zuru oke, akụkụ na enweghị mgbochi n'ụdị atọ nwere oke.Emepụtala ụdị “nrụgide-nrụgide” ma nyekwa ọnụọgụ nke mmetụta mmachi maka kọmpụta mechiri emechi.Wu et al.11 mepụtara usoro maka ịkọ nhụsianya-ntụkwasị obi nke ihe mgbochi FRP na-eburu n'uche mmetụta nha.Moran et al.12 tụlere njirimara mkpakọ axial monotonic nke constrained constrained na FRP helical strips wee wepụta usoro mgbakasị ahụ.Otú ọ dị, ọmụmụ ihe a dị n'elu na-enyocha ihe dị iche n'etiti kọnkịta nke ekpuchiri ekpuchi na akụkụ nke ọma.Amụbeghị nke ọma ọrụ FRPs na-amachi akụkụ kọmpụta nke ọma.
Tụkwasị na nke ahụ, ọmụmụ ihe ahụ tụlere arụmọrụ nke ihe mgbochi FRP na-arụ ọrụ n'ihe gbasara ike mkpakọ, mgbanwe mgbanwe, modul mbụ nke elasticity, na mgbagwoju anya n'okpuru ọnọdụ dị iche iche.Tijani et al.13,14 chọpụtara na nrụzi nke ihe nwere oke FRP na-ebelata site na mmebi na-abawanye na nnwale nrụzi FRP na kọmpụta mbụ mebiri emebi.Ma et al.[15] mụrụ mmetụta nke mmebi mbụ na kọlụm kọmpụta FRP na-amachibido ma tụlee na mmetụta nke ogo mmebi na ike nkwụsị bụ ihe na-adịghị mma, ma nwee mmetụta dị ukwuu na nrụrụ mpụta na ogologo oge.Agbanyeghị, Cao et al.16 hụrụ akụkụ mgbakasị ahụ na mgbakasị nhụsianya envelopu nke ihe mgbochi FRP na-emetụta mmebi mbụ.Na mgbakwunye na ọmụmụ banyere ọdịda nke mbụ, e mekwara ụfọdụ ọmụmụ banyere ịdịte aka nke ihe FRP nwere oke n'okpuru ọnọdụ gburugburu ebe obibi siri ike.Ndị ọkà mmụta sayensị a mụọla nbibi nke ihe mgbochi FRP n'okpuru ọnọdụ ọjọọ ma jiri usoro nleba anya nhụsianya mepụta ụdị mmebi iwu iji buru amụma ndụ ọrụ.Xie et al.17 debere ihe mgbochi FRP na gburugburu hydrothermal wee chọpụta na ọnọdụ hydrothermal na-emetụta nke ọma akụrụngwa nke FRP, na-ebute mbelata nke nta nke nta na ike mkpakọ ya.Na gburugburu acid-base, interface dị n'etiti CFRP na ihe na-akawanye njọ.Ka oge imikpu na-abawanye, ọnụ ọgụgụ nke ntọhapụ nke ike nke mbibi nke oyi akwa CFRP na-ebelata nke ukwuu, nke na-eduga ná mbibi nke ihe atụ interfacial18,19,20.Tụkwasị na nke ahụ, ụfọdụ ndị ọkà mmụta sayensị amụwokwa ihe dị n'ịtụ oyi na thawing na kọmpụta nwere oke FRP.Liu et al.21 kwuru na CFRP rebar nwere ezigbo ịdịte aka n'okpuru usoro mgbaze na-ekpo ọkụ dabere na modulus ike dị ike, ike mkpakọ, na oke nrụgide.Tụkwasị na nke ahụ, a na-atụ aro ihe nlereanya nke jikọtara ya na mmebi nke ihe eji arụ ọrụ nke ihe.Otú ọ dị, Peng et al.22 gbakọrọ ndụ nke CFRP na ihe adhesives iji okpomọkụ na ifriizi-thaw data okirikiri.Guang et al.23 duziri ule ngwa ngwa ifriizi-mgbaza nke ihe ma tụpụta usoro maka nyocha nguzogide ntu oyi dabere na ọkpụrụkpụ oyi akwa mebiri emebi n'okpuru mkpughe na friza.Yazdani et al.24 mụrụ mmetụta FRP n'ígwé na ntinye nke ion chloride n'ime ihe.Nsonaazụ gosiri na oyi akwa FRP na-eguzogide ọgwụ na-egbochi ihe dị n'ime site na ion chloride mpụta.Liu et al.25 simulated bee ule ọnọdụ maka sulfate-corroded FRP ihe, kere a slips nlereanya, na buru amụma mbibi nke FRP-concrete interface.Wang et al.26 hibere ụdị nrụgide nrụgide maka ihe mgbochi sulfate-eroded nke FRP site na ule mkpakọ uniaxial.Zhou et al.[27] mụọ mmebi nke kọmpat na-enweghị mgbochi kpatara site na ngwakọta friza-thaw cycles nke nnu na nke mbụ jiri ọrụ mgbagha kọwaa usoro ọdịda.Ọmụmụ ihe ndị a enweela ọganihu dị ukwuu n'ịtụle ịdịte aka nke ihe nwere oke FRP.Agbanyeghị, ọtụtụ ndị nyocha etinyela uche na ịmegharị mgbasa ozi erosive n'okpuru otu ọnọdụ adịghị mma.Concrete na-emebikarị n'ihi mbuze jikọtara ya na ọnọdụ gburugburu ebe obibi dị iche iche kpatara.Ọnọdụ gburugburu ebe obibi ndị a jikọtara ọnụ na-eweda arụmọrụ nke ihe mgbochi FRP.
Sulfation na ifriizi-mkpụrụkpụ cycles bụ ihe abụọ ahụkarị dị mkpa paramita na-emetụta anwụ ngwa ngwa nke ihe.Teknụzụ mpaghara mpaghara FRP nwere ike melite njirimara nke kọnkịtị.A na-eji ya eme ihe na injinia na nyocha, mana ugbu a nwere oke ya.Ọtụtụ ọmụmụ lekwasịrị anya na nguzogide nke ihe mgbochi FRP na-egbochi sulfate corrosion na mpaghara oyi.Usoro nke mbuze nke n'ụzọ zuru ezu gbachitere, ọkara-gbachikwara na-emeghe ihe site sodium sulfate na ifriizi-thaw kwesịrị ọzọ zuru ezu ọmụmụ, karịsịa ọhụrụ ọkara agbachikwara usoro akọwara n'isiokwu a.Amụkwara mmetụta nkwado na kọlụm kọmpụta site n'ịgbanwe usoro njide FRP na mbuze.Mgbanwe microcosmic na macroscopic dị na nlele nke ihe nbibi kpatara bụ nke e ji microscope eletrọn, ule pH, microscope eletrọn SEM, EMF energy spectrum analysis na uniaxial mechanical test.Tụkwasị na nke a, ọmụmụ ihe a na-atụle iwu na-achịkwa mmekọrịta nrụgide-mmetụta nke na-eme na ule uniaxial mechanical.A kwadoro oke nrụgide na ụkpụrụ nhụsianya nke nnwale ahụ site na nyocha njehie site na iji ụdị nrụgide nrụgide anọ dị adị.Ihe nlereanya a tụrụ aro nwere ike ịkọ n'ụzọ zuru ezu oke kachasị na ike nke ihe ahụ, nke bara uru maka omume nkwado FRP n'ọdịnihu.N'ikpeazụ, ọ na-eje ozi dị ka ihe ndabere echiche maka FRP kpọmkwem ntu oyi ntu oyi echiche.
Ọmụmụ ihe a na-enyocha mmebi nke ihe nwere oke FRP na-eji sulfate ngwọta corrosion yana ngwakọta na okirikiri friza-thaw.Egosiputala mgbanwe a na-ahụ anya na macroscopic site na mbuze kọnkịtị site na iji nyocha eletrọnịkị eletrọnịkị, nnwale pH, spectroscopy ume EDS, na nnwale uniaxial.Tụkwasị na nke ahụ, a na-enyocha ihe eji arụ ọrụ na mgbanwe nrụgide-mgbanwe nke ihe FRP na-egbochi mbuze nke jikọtara ya site na iji nnwale mkpakọ axial.
FRP Confined Concrete nwere ihe eji eme ihe, ihe mkpuchi elu FRP na nrapado epoxy.A na-ahọrọ ihe mkpuchi ihe abụọ dị n'èzí: CFRP na GRP, a na-egosipụta njirimara nke ihe ndị ahụ na Tebụl 1. A na-eji resin Epoxy A na B mee ihe dị ka nrapado (nchịkọta ngwakọta 2: 1 site na olu).Osikapa.1 na-akọwa nkọwa nke iwu nke ihe ngwakọta ihe.Na eserese 1a, ejiri simenti Swan PO 42.5 Portland mee ihe.A na-egweri mkpokọta nkume basalt na dayameta nke 5-10 na 10-19 mm n'otu n'otu, dị ka egosiri na fig.1b na c.Dị ka mma ndochi na fig. 1g ji eke osimiri ájá na a fineness modulus nke 2.3.Kwadebe ngwọta nke sodium sulfate site na granules nke anhydrous sodium sulfate na mmiri ụfọdụ.
Ngwakọta nke ngwakọta ihe: a - ciment, b - nchịkọta 5-10 mm, c - nchịkọta 10-19 mm, d - ájá osimiri.
Ike imewe nke ihe bụ 30 MPa, nke na-ebute nrụpụta ciment ọhụrụ nke 40 ruo 100 mm.E gosipụtara nha ngwakọta ihe dị na tebụl 2, yana nha nke mkpokọta 5-10 mm na 10-20 mm bụ 3: 7.E gosipụtara mmetụta nke mmekọrịta na gburugburu ebe obibi site na mbụ ịkwadebe ngwọta 10% NaSO4 wee wụsa ngwọta ahụ n'ime ụlọ ikuku na-ekpo ọkụ.
A na-akwadebe ngwakọta concrete na 0,5 m3 na-amanye mixer na ihe niile nke ihe eji eme ihe iji tinye ihe nlele achọrọ.Nke mbụ, a na-akwadebe ihe ndị a na-emepụta ihe dị ka Tebụl 2 si dị, na ciment, ájá na mkpokọta na-edozi ahụ maka nkeji atọ.Mgbe ahụ, kesaa mmiri ahụ nke ọma ma kpalie maka nkeji 5.Na-esote, a na-atụba ihe nlele n'ụdị cylindrical na kọmpat na tebụl na-ama jijiji (dayameta nke 10 cm, ịdị elu 20 cm).
Mgbe ọgwụgwọ maka ụbọchị 28, a na-ekechi ihe nlele ahụ na ihe FRP.Ọmụmụ ihe a na-atụle ụzọ atọ maka kọlụm kọmpụta agbasiri ike, gụnyere nke agbachichara nke ọma, nke nwere obere mgbochi na enweghị mmachi.A na-eji ụdị abụọ, CFRP na GFRP, maka ihe ndị nwere oke.FRP kpuchiri shei kọmpụta FRP zuru oke, 20 cm dị elu yana ogologo 39 cm.E jighị epoxy mechie elu na ala nke konkịtị FRP.Usoro nyocha nke ọkara-hermetic dị ka teknụzụ ikuku ikuku echere na nso nso a ka akọwara dị ka ndị a.
(2) Iji onye na-achị achị, dọpụta ahịrị n'elu cylindrical kọmpụta iji chọpụta ọnọdụ nke ibe FRP, ebe dị anya n'etiti ibe ya bụ 2.5 cm.Mgbe ahụ, kechie teepu ahụ gburugburu ebe ndị FRP na-adịghị mkpa.
(3) A na-eji akwụkwọ aja na-ehicha elu ahụ nke ọma, were ajị mmanya na-egbutu ya ma were epoxy kpuchie ya.Mgbe ahụ, jiri aka gị tinye eriri fiberglass ahụ n'elu kọmpat ma wepụ oghere ndị ahụ ka fiberglass wee na-arapara n'elu ihe ahụ ma zere ikuku ikuku.N'ikpeazụ, kpachie ibe FRP ahụ n'elu kọmpụta site n'elu ruo na ala, dịka akara ndị ejiri onye na-achị achị si dị.
(4) Mgbe ọkara otu awa gachara, lelee ma kọnti ahụ kewapụrụ na FRP.Ọ bụrụ na FRP na-apụ apụ ma ọ bụ na-apụ apụ, ekwesịrị idozi ya ozugbo.A ga-agwọrịrị ụdị ihe a kpụrụ akpụ maka ụbọchị 7 iji hụ na ike gwọrọ.
(5) Mgbe gwọchara, jiri mma iji wepụ teepu ahụ n'elu ihe ahụ, ma mesịa nweta kọlụm kọlụm FRP nke ọkara-hermetic.
E gosipụtara nsonaazụ n'okpuru mmachi dị iche iche na fig.2. Ihe onyonyo 2a na-egosi kọmpụta CFRP gbachitere nke ọma, eserese 2b na-egosi kọmpụta CFRP nke ọkara-generalized, eserese 2c na-egosi kọmpụta GFRP zuru oke, yana eserese 2d na-egosi kọmpụta CFRP nwere ọkara.
Ụdị agbachitere: (a) CFRP zuru oke;(b) eriri carbon emechiri emechi;(c) mechie kpamkpam na fiberglass;(d) fiberglass agbachiri ọkara.
Enwere isi ihe anọ emebere iji nyochaa mmetụta mgbochi FRP na usoro mbuze na arụmọrụ njikwa mbuze nke cylinders.Tebụl 3 na-egosi ọnụọgụ kọlụm kọlụm.Nlereanya maka otu ọ bụla nwere ihe nlele ọkwa atọ yiri ka data ahụ na-agbanwe agbanwe.A tụlere ihe nlele atọ maka nsonaazụ nnwale niile n'isiokwu a.
(1) A na-ekewa ihe anaghị ekpuchi ikuku dị ka carbon fiber ma ọ bụ fiberglass.E mere ntụnyere nke mmetụta nke ụdị abụọ nke eriri na nkwado nke kọnkịta.
(2) Ụzọ njide kọlụm concrete na-ekewa ụzọ atọ: oke zuru oke, nke nwere oke na enweghị oke.Atụnyere nguzogide mbuze nke kọlụm kọmpụta nwere ọkara gbachiri ya na ụdị abụọ ọzọ.
(3) Ọnọdụ mbuze bụ cycles friza-thaw gbakwunyere ngwọta sulfate, na ọnụ ọgụgụ nke cycles-thaw bụ 0, 50 na 100 ugboro, n'otu n'otu.A mụọla mmetụta nke mbuze jikọtara ọnụ na kọlụm kọmpụta FRP.
(4) A na-ekewa iberibe ule ahụ ụzọ atọ.Nke mbụ bụ FRP wrapping na mgbe corrosion, nke abụọ bụ corrosion mbụ na mgbe ahụ wrapping, na nke atọ otu bụ corrosion mbụ na mgbe wrapping na mgbe corrosion.
Usoro nnwale a na-eji igwe nyocha nke ụwa niile, igwe nnwale tensile, nkeji okirikiri friza-thaw (ụdị CDR-Z), microscope eletrọn, mita pH, ihe nlele, ngwaọrụ nchụpụ, microscope elektrọn SEM, na EDS ike spectrum analyzer na ọmụmụ a.Ihe atụ bụ kọlụm kọlụm 10 cm dị elu na 20 cm n'obosara.A gwọchara ihe ahụ n'ime ụbọchị 28 ka wụsa na nchịkọta, dị ka egosiri na foto 3a.A na-akwatu ihe nlele niile ka emechara nkedo ma debe ya maka ụbọchị 28 na 18-22 Celsius C na iru mmiri 95%, wee jiri fiberglass kechie ụfọdụ nlele.
Uzo nnwale: (a) akụrụngwa maka idobe okpomọkụ na iru mmiri mgbe niile;(b) igwe na-eme okirikiri friza;(c) igwe nyocha nke ụwa;(d) onye nyocha pH;(e) nlele anya.
Nnwale friza-thaw na-eji usoro ifriizi ọkụ dị ka egosiri na foto 3b.Dị ka GB/T 50082-2009 “Durability Standards for Conventional Concrete” si kwuo, a na-emikpu ihe nlere anya kpam kpam na 10% sodium sulfate solution na 15-20ºC maka ụbọchị 4 tupu oyi na thawing.Mgbe nke ahụ gasịrị, mwakpo sulfate na-amalite ma kwụsị n'otu oge na okirikiri friza-thaw.Oge okirikiri friza-thaw bụ awa 2 ruo 4, na oge ntu oyi ekwesịghị ịbụ ihe na-erughị 1/4 nke oge okirikiri.Ekwesịrị idobe okpomọkụ isi ihe nlele n'ime oke site na (-18± 2) ruo (5± 2) Celsius.Ntugharị site na oyi kpọnwụrụ gaa na ntọhapụ ekwesịghị iwe ihe karịrị nkeji iri.A na-eji ihe atụ atọ cylindrical yiri nke ọ bụla n'ụdị ọ bụla iji mụọ mbelata ịdị arọ na pH mgbanwe nke ngwọta n'elu 25 friza-thaw cycles, dị ka e gosiri na fig. 3d.Mgbe usoro ntu oyi 25 ọ bụla gachara, a na-ewepụ ihe nlele ndị ahụ wee hichaa ebe ndị ahụ tupu ekpebie ịdị arọ ha (Wd).Emere nnwale niile n'ime ugboro atọ nke ihe nlele ahụ, na nkezi ụkpụrụ ka ejiri kparịta nsonaazụ ule.A na-ekpebi usoro maka ọnwụ nke oke na ike nke ihe nlele ahụ dị ka ndị a:
N'ime usoro ahụ, ΔWd bụ ọnwụ dị arọ (%) nke ihe nlele mgbe ọ bụla 25 na-eme ka ọkpụkpụ na-eme ka ọ dị jụụ, W0 bụ nkezi arọ nke ihe nlele tupu oge oyi-thaw (kg), Wd bụ nkezi ihe dị arọ.arọ nke sample mgbe 25 ifriizi-thaw cycles (kg).
A na-eji ọnụọgụ mmebi ike nke ihe nlele ahụ bụ Kd, usoro ngụkọ bụ nke a:
N'ime usoro ahụ, ΔKd bụ ọnụego ike ọnwụ (%) nke ihe nlele mgbe ọ bụla 50 na-eme ka mmiri na-ekpo ọkụ, f0 bụ nkezi ike nke ihe nlele tupu oge nkwụsịtụ-thaw (MPa), fd bụ nkezi ike nke ihe nlele maka 50 friza-thaw cycles (MPa).
Na fig.3c na-egosi igwe nyocha mkpakọ maka ihe nlere anya.Dabere na "Standard for Test Method for the Physical and Mechanical Properties of Concrete" (GBT50081-2019), a kọwapụtara usoro maka ịnwale kọlụm kọmpụta maka ike mkpakọ.Ọnụego ntinye na ule mkpakọ bụ 0.5 MPa / s, a na-eji ntinye na-aga n'ihu na usoro n'usoro n'oge ule ahụ.Edekọrọ njikọ mbugharị ibu maka ihe nlere anya n'oge nnwale igwe.A na-etinye ihe nrịbama n'elu mpụta nke konkịtị na FRP nke ụdị ihe atụ iji tụọ eriri axial na kehoraizin.A na-eji cell strain na nyocha igwe iji dekọọ mgbanwe n'ụdị ụdị n'oge ule mkpakọ.
N'oge ọ bụla 25 na-agbaze oyi, a na-ewepụ ihe nlere nke ihe ngwọta ntu oyi ma tinye ya n'ime akpa.Na fig.3d na-egosi ule pH nke ngwọta nlele n'ime akpa.A na-egosi nyocha microscopic nke elu na akụkụ obe nke ihe nlele n'okpuru ọnọdụ friza-thaw na Fig. 3d.A na-ahụ ọnọdụ elu nke ụdị dị iche iche mgbe 50 na 100 friza-thaw cycles na ngwọta sulfate na-ahụ n'okpuru microscope.Igwe microscope na-eji nkwalite 400x.Mgbe ị na-elele elu nke ihe nlele ahụ, a na-ahụ oke mbibi nke oyi akwa FRP na oyi akwa nke mpụta.Nleba anya n'ofe akụkụ nke sample na-ahọrọ n'ụzọ bụ isi na ozize ọnọdụ na anya nke 5, 10 na 15 mm si n'elu oyi akwa.Nhazi nke ngwaahịa sulfate na okirikiri ifriizi-na-achọ nnwale ọzọ.Ya mere, a na-enyocha elu elu nke ihe nlele ndị ahọpụtara site na iji nyocha eletrọnịkị eletrọnịkị (SEM) nke nwere ihe nleba anya ike (EDS).
Jiri microscope eletrọn lelee elu nlele ahụ wee họrọ mmụba 400X.Ogo nke mmebi elu na ọkara-agbachiri na nke na-enweghị njikọ GRP n'okpuru usoro ikuku ifriizi na ikpughe na sulfates dị oke elu, ebe n'ime kọmpụta kpuchiri ya nke ọma ọ bụ negligible.Ụdị nke mbụ na-ezo aka n'ihe omume nke mbuze nke ihe na-asọ oyi site na sodium sulfate na site na 0 ruo 100 cycles na-ekpo ọkụ, dị ka egosiri na Fig. 4a.Ihe nlere anya na-enweghị mkpughe ntu oyi nwere elu dị larịị na-enweghị atụmatụ a na-ahụ anya.Mgbe ihe iri ise gachara, ihe mgbochi pulp dị n'elu kpochapụrụ nke ọma, na-ekpughe shei ọcha nke pulp ahụ.Mgbe 100 erosions gasịrị, shells nke ihe ngwọta ahụ dara kpamkpam n'oge nlele anya nke elu ihe.Nleba anya n'ile anya na-egosi na elu nke 0 friza-thaw e mebiri emebi dị mma na mkpokọta elu na ngwa agha nọ n'otu ụgbọ elu.A hụrụ elu kwụ ọtọ na nke siri ike n'elu kọmpụta nke okirikiri 50 na-ekpori ọkụ mebie.Enwere ike ịkọwa nke a site n'eziokwu ahụ bụ na a na-ebibi ụfọdụ ngwa agha na obere obere kristal granular na-acha ọcha na-agbaso n'elu, bụ nke kachasị nke mkpokọta, ngwa agha na kristal ọcha.Mgbe usoro 100 na-ekpo ọkụ na-ekpo ọkụ gasịrị, nnukwu kristal na-acha ọcha pụtara n'elu ihe ahụ, ebe nchịkọta gbara ọchịchịrị na-ekpuchi na mpụga gburugburu ebe obibi.Ka ọ dị ugbu a, ihe dị n'elu a na-ahụkarị bụ mkpokọta na kristal ọcha.
Nkà mmụta ihe ọmụmụ nke kọlụm kọlụm na-ekpo ọkụ na-ekpo ọkụ: (a) kọlụm kọlụm na-enweghị mgbochi;(b) ihe mgbakwasị ụkwụ na-agbachi agbachi agbachi;(c) GRP ihe ejikọtara ọkara;(d) CFRP ihe mkpuchi zuru oke;(e) GRP konkịtị gbara okirikiri.
Nke abụọ udi bụ corrosion nke semi-hermetic CFRP na GRP ihe ogidi n'okpuru ifriizi-thaw cycles na ikpughe na sulfates, dị ka e gosiri na fig. 4b, c.Nnyocha anya (1x magnification) gosiri na ntụ ntụ ọcha ji nwayọọ nwayọọ na-etolite n'elu oyi akwa fibrous, nke na-ada ngwa ngwa na-abawanye na ọnụ ọgụgụ nke friza-thaw cycles.Mbibi elu na-enweghị mmachi nke ọkara-hermetic FRP konkịtị bịara pụtakwuo ka ọnụ ọgụgụ nke cycles-thaw na-abawanye.Ihe a na-ahụ anya nke "bloating" (n'elu oghere nke ngwọta nke kọlụm kọlụm dị na njedebe nke ọdịda).Otú ọ dị, ihe mkpuchi nke eriri carbon dị n'akụkụ na-egbochi ihe omume peeling.N'okpuru microscope, eriri carbon sịntetik na-apụta dị ka eriri ọcha na ndabere ojii na mmụba 400x.N'ihi ọdịdị gburugburu nke eriri na ikpughe na ìhè na-enweghị isi, ha na-acha ọcha, mana eriri carbon n'onwe ha bụ oji.Fiberglass bụ eriri na-acha ọcha na mbụ, ma mgbe a na-ejikọta ya na nrapado, ọ na-apụta ìhè na ọnọdụ nke ihe dị n'ime fiberglass na-ahụ anya nke ọma.Fiberglass na-egbuke egbuke na-acha ọcha na ihe nkedo ahụ na-acha odo odo.Ha abụọ dị nnọọ ọkụ na agba, ya mere agba nke gluu ga-ezobe eriri fiberglass, na-enye ọdịdị zuru oke na-acha odo odo.A na-echebe carbon na eriri enyo ka ọ ghara imebi ya site na resin epoxy mpụga.Ka ọnụ ọgụgụ nke mwakpo friza-thaw na-abawanye, ọtụtụ oghere na kristal ọcha ole na ole pụtara n'elu.Ka usoro nke sulfate na-akpụ akpụ na-abawanye, ihe nkedo ahụ na-eji nwayọọ nwayọọ na-adị gịrịgịrị, agba odo na-apụ n'anya, a na-ahụkwa eriri ndị ahụ.
Udi nke ato bu corrosion nke CFRP na GRP kpuchiri ekpuchi n'uju n'okpuru okirikiri ntu oyi na ikpughe na sulfates, dika egosiri na Fig. 4d, e.Ọzọ, nsonaazụ a na-ahụ anya yiri nke abụọ maka ụdị nke abụọ nke ngalaba mgbochi nke kọlụm kọlụm.
Tulee ihe ịtụnanya a hụrụ mgbe itinyechara usoro njide atọ ndị akọwara n'elu.Anụ ahụ fibrous dị n'ime ihe mkpuchi FRP zuru oke na-anọgide na-akwụsi ike ka ọnụọgụ nke cycles na-agbaze na-abawanye.N'aka nke ọzọ, akwa mgbanaka nrapado dị ntakịrị n'elu.Epoxy resins na-emeghachi omume na ion hydrogen nọ n'ọrụ na sulfuric acid mepere emepe ma ọ naghị emeghachi omume na sulfates28.N'ihi ya, enwere ike iche na mbuze na-agbanwekarị njirimara nke oyi akwa nrapado n'ihi usoro ikuku na-ekpo ọkụ, si otú ahụ gbanwee mmetụta na-agba ume nke FRP.Ihe dị n'elu nke FRP semi-hermetic konkret nwere otu ihe na-emebi emebi dị ka elu kọntakịrị na-enweghị mgbochi.Igwe oyibo FRP ya dabara na oyi akwa FRP nke kọmpụta kpuchiri ya nke ọma, na mmebi ahụ apụtaghị ìhè.Otú ọ dị, n'ime ihe nkedo GRP nke kpuchiri ekpuchi, nnukwu mgbawa mmiri na-eme ebe eriri eriri na-ejikọta ya na kọmpat ekpughere.Mbibi nke ihe ndị e kpughepụrụ ekpuchi ekpuchi na-akawanye njọ ka ọnụ ọgụgụ nke okirikiri oyi na-agbaze na-abawanye.
Ihe dị n'ime ụlọ nke ihe mkpuchi FRP zuru oke, nke nwere ọkara, na enweghị mgbochi gosipụtara ọdịiche dị ịrịba ama mgbe a na-etinye ya na cycles na-ekpo ọkụ na ikpughe na ngwọta sulfate.A na-egbutu ihe nlele ahụ na ntụgharị ma hụ akụkụ obe site na iji microscope eletrọn na mmụba 400x.Na fig.5 na-egosi ihe onyonyo a na-ahụ anya n'ebe dị anya nke 5 mm, 10 mm na 15 mm site na oke n'etiti konkịta na ngwa agha, n'otu n'otu.A chọpụtala na mgbe a na-ejikọta sodium sulfate ngwọta na friza-thaw, a na-eji nwayọọ nwayọọ na-emebi ihe mebiri emebi site n'elu ruo n'ime ime.N'ihi na ọnọdụ mmebi nke ime nke CFRP na ihe mgbochi GFRP bụ otu, ngalaba a anaghị atụnyere ihe abụọ ahụ.
Nleba anya nke microscopic n'ime akụkụ nke kọlụm nke kọlụm: (a) njedebe kpamkpam site na fiberglass;(b) nke ejiri fiberglass mechie ọkara;(c) enweghị oke.
E gosipụtara nbibi nke ime FRP na kọmpụta agbachiela nke ọma na fig.5a.A na-ahụ mgbawa na 5 mm, elu ahụ dị nro, ọ dịghị kristal.Elu dị larịị, na-enweghị kristal, oke 10 ruo 15 mm.E gosipụtara nbibi nke ime ihe nke FRP semi-hermetic na fig.5 B. A na-ahụ mgbawa na kristal ọcha na 5mm na 10mm, na elu dị nro na 15mm.Ọgụgụ 5c na-egosi akụkụ nke kọlụm FRP siri ike ebe ahụrụ mgbawa na 5, 10 na 15 mm.Kristal na-acha ọcha ole na ole na mgbawa ahụ bịara na-adịwanye ụkọ ka mgbawa ahụ na-esi n'èzí nke ihe ahụ gaa n'ime.Ogidi kọmpụta na-adịghị agwụ agwụ gosipụtara oke mbuze, nke na-esote kọlụm kọmpụta FRP nwere obere ihe.Sodium sulfate enwechaghị mmetụta n'ime ime nke ihe atụ FRP kpuchiri ekpuchi nke ọma karịa okirikiri 100 na-ekpori ọkụ.Nke a na-egosi na isi ihe na-ebute mbuze nke ihe FRP nwere mmachi zuru oke na-ejikọta ya na nbibi na-agbaze oyi n'ime oge.Nleba anya n'ofe akụkụ ahụ gosiri na akụkụ ahụ ozugbo tupu oyi na thawing dị nro na enweghị nchịkọta.Ka ihe ahụ na-agbaze ma na-agbaze, a na-ahụ ihe mgbawa, otu ihe ahụ bụ maka nchịkọta, na kristal granular na-acha ọcha na-ekpuchi ya na mgbawa.Studies27 gosiri na mgbe a na-etinye ihe n'ime ihe ngwọta sodium sulfate, sodium sulfate ga-abanye n'ime ihe ahụ, ụfọdụ n'ime ha ga-ebuli dị ka crystals sodium sulfate, ụfọdụ ga-eji ciment mee ihe.Kristal sulfate sodium na ngwaahịa mmeghachi omume dị ka granules ọcha.
FRP na-egbochi kpam kpam mgbawa ihe na-emebi emebi, mana akụkụ ahụ dị nro na-enweghị kristal.N'aka nke ọzọ, akụkụ FRP nke mechiri emechi na nke na-enweghị ihe mgbochi ewepụtala mgbawa dị n'ime na kristal n'okpuru oke mbuze.Dị ka nkọwa nke ihe oyiyi na gara aga ọmụmụ29, a na-ekewa usoro mmebi nke nkwonkwo nke FRP ihe na-enweghị njedebe na nke na-egbochi ya na nkebi abụọ.A na-ejikọta ọkwa mbụ nke ihe mgbawa ihe na mgbasawanye na nkwụsịtụ n'oge friza-thaw.Mgbe sulfate na-abanye n'ime ihe ahụ wee bụrụ nke a na-ahụ anya, sulfate kwekọrọ na ya na-ejupụta cracks kere site na mbelata site na friza-thaw na mmeghachi omume hydration.Ya mere, sulfate nwere mmetụta nchebe pụrụ iche na ihe n'oge mmalite ma nwee ike imeziwanye ihe ndị na-arụ ọrụ nke ihe na-arụ ọrụ ruo n'ókè ụfọdụ.Nkeji nke abụọ nke ọgụ sulfate na-aga n'ihu, na-abanye n'ime mgbawa ma ọ bụ ihe efu na-emeghachi omume na ciment iji mepụta alum.N'ihi ya, mgbawa na-eto eto ma na-akpata mmebi.N'ime oge a, mmeghachi omume mgbasawanye na nkwụsị nke jikọtara na oyi na thawing ga-eme ka mmebi dị n'ime ahụ dịkwuo njọ na kọmpụta ahụ, na-ebute mbelata ikike ibu.
Na fig.6 na-egosi mgbanwe pH nke ihe ngwọta impregnation siri ike maka ụzọ atọ nwere oke elele anya mgbe 0, 25, 50, 75, na 100 na-agbaze cycles.Ngwa ngwa FRP anaghị egbochi yana nke mechiri emechi gosipụtara pH kacha ọsọ site na 0 ruo 25 okirikiri friza.Ụkpụrụ pH ha si na 7.5 ruo 11.5 na 11.4, n'otu n'otu.Dị ka ọnụ ọgụgụ nke friza-thaw cycles na-abawanye, pH ịrị elu nke nta nke nta jiri nwayọọ nwayọọ na-ebelata ka 25-100 na-agbaze cycles.Ụkpụrụ pH ha si na 11.5 na 11.4 ruo 12.4 na 11.84, n'otu n'otu.N'ihi na ihe FRP nwere njikọ zuru oke na-ekpuchi oyi akwa FRP, ọ na-esiri ike sodium sulfate ngwọta ịbanye.N'otu oge ahụ, ọ na-esiri ike ịmepụta ciment na-abanye n'ime ngwọta nke mpụga.Ya mere, pH ji nke nta nke nta mụbaa site na 7.5 ruo 8.0 n'etiti 0 na 100 cycles-frize-thaws.A na-enyocha ihe kpatara mgbanwe na pH dị ka ndị a.Silicate dị na kọnkịrị na-ejikọta ya na ion hydrogen na mmiri ka ọ bụrụ silicic acid, na OH fọdụrụnụ na-ebuli pH nke ngwọta jupụtara.Mgbanwe nke pH pụtara karịa n'etiti 0-25 okirikiri oyiri na obere akpọpụta n'etiti 25-100 friza-thaw cycles30.Agbanyeghị, achọpụtara ebe a na pH gara n'ihu na-abawanye mgbe okirikiri 25-100 gachara.Enwere ike ịkọwa nke a site n'eziokwu ahụ bụ na sodium sulfate na-emeghachi omume n'ime ime ihe, na-agbanwe pH nke ngwọta.Nyocha nke ihe mejupụtara kemịkalụ na-egosi na kọnkịtị na-emeghachi omume na sodium sulfate n'ụzọ ndị a.
Usoro (3) na (4) na-egosi na sodium sulfate na calcium hydroxide na ciment bụ gypsum (calcium sulfate), na calcium sulfate na-emeghachi omume na calcium metaaluminate na ciment iji mepụta kristal alum.Mmeghachi omume (4) na-esonyere ya na nhazi nke isi OH-, nke na-eduga na mmụba nke pH.Ọzọkwa, ebe ọ bụ na mmeghachi omume a na-agbanwe agbanwe, pH na-ebili n'otu oge ma gbanwee nwayọọ nwayọọ.
Na fig.7a na-egosi mbelata ịdị arọ nke ihe kpuchiri ekpuchi nke ọma, nke kpuchiri ekpuchi, yana kpọchiri akpọchi GRP n'oge cycles friza na ngwọta sulfate.Mgbanwe kachasị pụta ìhè na mfu oke bụ ihe na-enweghị njedebe.Ihe na-enweghị mgbochi tụfuru ihe dịka 3.2% nke oke ya mgbe mwakpo 50 friza-thaw na ihe dị ka 3.85% mgbe mwakpo 100 kpochara.Nsonaazụ na-egosi na mmetụta nke conjugated mbuze na àgwà nke free-asọpụta cycles na-ebelata ka ọnụ ọgụgụ nke ifriizi-thaws cycles na-abawanye.Otú ọ dị, mgbe a na-ekiri elu nke ihe nlele ahụ, a chọpụtara na mfu nke ngwa agha mgbe 100 cycles-frize-thaw cycles dị ukwuu karịa mgbe 50 gachara.Ejikọtara ya na ọmụmụ ihe na ngalaba nke gara aga, enwere ike iche na ntinye nke sulfates n'ime ihe na-eduga n'ịkwụsị mbelata nke oke ọnwụ.Ka ọ dị ugbu a, alum na gypsum emepụtara n'ime ya na-ebutekwa ibulata nwayọ nwayọ, dị ka amụma kemịkal (3) na (4) buru amụma.
Mgbanwe ibu: (a) mmekọrịta dị n'etiti mgbanwe ịdị arọ na ọnụọgụ nke cycles-freze-thaws;(b) mmekọrịta dị n'etiti mgbanwe oke na uru pH.
Mgbanwe nke ọnwụ arọ nke FRP semi-hermetic concrete na-ebu ụzọ ebelata wee na-abawanye.Mgbe okirikiri 50 ifriizi-thaw gachara, oke mfu nke fiberglass semi-hermetic bụ ihe dịka 1.3%.Mbelata arọ mgbe 100 cycles bụ 0.8%.Ya mere, enwere ike ikwubi na sodium sulfate na-abanye n'ime ihe na-enweghị ihe ọ bụla.Na mgbakwunye, nleba anya n'elu mpempe ule gosikwara na eriri eriri nwere ike iguzogide nsị ngwa agha n'ebe a na-emeghe, si otú a na-ebelata ibu ibu.
Mgbanwe nke oke mfu nke ihe FRP emechiela nke ọma dị iche na nke abụọ mbụ.Mass anaghị atụfu, ma na-agbakwụnye.Mgbe 50 ntu oyi gachara erosions, oke ahụ mụbara ihe dịka 0.08%.Mgbe ugboro 100 gasịrị, oke ya mụbara ihe dịka 0.428%.Ebe ọ bụ na a na-awụsa ihe ahụ kpamkpam, ngwa agha dị n'elu ihe ahụ agaghị apụ ma ọ gaghị eme ka ọ ghara ịdị mma.N'aka nke ọzọ, ntinye nke mmiri na sulfates site na elu ọdịnaya dị elu n'ime ime nke obere ihe na-eme ka ọ dịkwuo mma.
Emeela ọtụtụ ọmụmụ na mbụ gbasara mmekọrịta dị n'etiti pH na mfu oke na ihe mgbochi FRP n'okpuru ọnọdụ mkparị.Ọtụtụ n'ime nyocha a tụlere mmekọrịta dị n'etiti mfu oke, mgbanwe mgbanwe na mfu ike.Na fig.7b na-egosi njikọ dị n'etiti pH siri ike na mfu oke n'okpuru mgbochi atọ.A na-atụpụta ụkpụrụ amụma iji buo amụma mfu n'efu site na iji ụzọ njigide atọ na ụkpụrụ pH dị iche iche.Dịka a na-ahụ na eserese 7b, ọnụọgụ Pearson dị elu, na-egosi na enwere njikọ n'etiti pH na mfu oke.Ụkpụrụ r-squared maka enweghị mmachi, nke nwere obere ihe, na ihe mgbochi zuru oke bụ 0.86, 0.75, na 0.96, n'otu n'otu.Nke a na-egosi na pH mgbanwe na ịdị arọ ọnwụ nke ihe mkpuchi n'ụzọ zuru ezu bụ dịtụ linear n'okpuru ma sulfate na friza ọnọdụ.N'ime ihe na-enweghị ihe mgbochi na ọkara-hermetic FRP, pH ji nwayọọ nwayọọ na-abawanye ka ciment na-emeghachi omume na ngwọta mmiri.N'ihi ya, a na-eji nwayọọ nwayọọ na-ebibi ihe dị n'elu, nke na-eduga n'ịdị arọ.N'aka nke ọzọ, pH nke ihe mkpuchi zuru ezu na-agbanwe ntakịrị n'ihi na oyi akwa FRP na-ebelata mmeghachi omume kemịkalụ nke ciment na mmiri mmiri.Ya mere, maka ihe mkpuchi zuru oke, ọ dịghị ihe na-ahụ anya n'elu elu, ma ọ ga-ebu ibu n'ihi saturation n'ihi nnabata nke ngwọta sulfate.
Na fig.8 na-egosi nsonaazụ nke nyocha SEM nke ihe atụ nke etinyere na sodium sulfate freeze-thaw.Electron microscopy nyochara ihe nlele ndị anakọtara site na blọk ewepụtara n'elu oyi akwa nke kọlụm.Ọgụgụ 8a bụ onyonyo microscope eletrọn na-enyocha ihe kọmpụta anaghị emechi tupu ezeze.A na-achọpụta na e nwere ọtụtụ oghere n'elu ihe atụ, nke na-emetụta ike nke kọlụm kọlụm n'onwe ya tupu ntu oyi-thawing.Na fig.8b na-egosi onyonyo microscope eletrọn nke ihe nlele FRP nwere mkpuchi zuru oke mgbe okirikiri 100 kpochara.Enwere ike ịhụ mgbawa na nlele ahụ n'ihi oyi na agbaze.Otú ọ dị, elu ahụ dị nro ma ọ dịghị kristal dị na ya.Ya mere, a na-ahụkwa mgbawa na-ejuputaghị.Na fig.8c na-egosi ihe nlele nke ọkara-hermetic GRP ihe mgbe 100 ntu oyi mbuze okirikiri.O doro anya na mgbawa na-agbasawanye na mkpụrụ osisi kpụrụ n'etiti mgbawa.Ụfọdụ n'ime ihe ndị a na-etinye onwe ha na mgbawa.A na-egosi nyocha SEM nke ihe nlele nke kọlụm kọlụm enweghị mmachi na eserese 8d, ihe omume kwekọrọ na mmachi ọkara.Iji kọwakwuo ihe mejupụtara nke ihe ndị ahụ, a na-emewanye ihe ndị dị na mgbawa ahụ ma nyochaa site na iji EDS spectroscopy.Ahụhụ na ihu ọma na-abịa atọ dị iche iche shapes.Dịka nyocha nke ike ike, ụdị nke mbụ, dị ka egosiri na eserese 9a, bụ kristal ngọngọ mgbe niile, nke kachasị nke O, S, Ca na ihe ndị ọzọ mejupụtara.Site na ijikọta usoro ndị gara aga (3) na (4), enwere ike ikpebi na isi ihe dị n'ime ihe bụ gypsum (calcium sulfate).E gosiri nke abụọ na foto 9b;dị ka ike spectrum analysis si kwuo, ọ bụ ihe acicular na-abụghị ntụziaka, na isi ihe mejupụtara ya bụ O, Al, S na Ca.Nchikota Ezi ntụziaka na-egosi na ihe mejupụtara tumadi nke alum.Nke atọ ngọngọ egosiri na fig. 9c, bụ oge ufodu ngọngọ, kpebisiri ike ike ụdịdị dị iche iche analysis, tumadi mejupụtara components O, Na na S. Ọ tụgharịrị na ndị a bụ tumadi sodium sulfate crystals.Nnyocha microscopy eletrọn gosiri na ọtụtụ n'ime oghere ndị ahụ jupụtara na kristal sodium sulfate, dị ka egosiri na foto 9c, yana obere gypsum na alum.
Electron microscopic onyunyo nke sample tupu na mgbe corrosion: (a) emepe ihe tupu corrosion;(b) mgbe corrosion gasịrị, a na-emechi fiberglass ahụ kpamkpam;(c) mgbe corrosion nke GRP ọkara-gbachiri ihe;(d) mgbe corrosion nke oghe konkịtị gasịrị.
Nyocha ahụ na-enye anyị ohere ikpebi nkwubi okwu ndị a.Onyonyo microscope eletrọn nke ihe atụ atọ ahụ bụ 1k × na ihe mgbawa na ngwaahịa mbuze ka achọtara wee hụ na onyonyo a.Kọnkịta na-akparaghị ókè nwere mgbawa kachasị obosara ma nwee ọtụtụ ọka.FRP ọkara-nrụgide ihe dị ala na-abụghị nrụgide ihe na okwu nke mgbape obosara na urughuru ọnụ.Kọnkịta FRP gbachiri nke ọma nwere obosara mgbape kacha nta na enweghị ihe irighiri ihe mgbe oke ikuku jụrụ oyi.Ihe ndị a niile na-egosi na kọmpụta FRP emechiri nke ọma bụ nke kacha nwee ike ibute mbuze site na ifriizi na cha cha.Usoro kemịkalụ n'ime ọkara-agbachi na ogidi FRP mepere emepe na-eduga na nguzobe nke alum na gypsum, na ntinye sulfate na-emetụta porosity.Ọ bụ ezie na cycles friza-thaw bụ isi ihe kpatara mgbawa kọnkịtị, sulfates na ngwaahịa ha na-ejupụta ụfọdụ mgbawa na pores na mbụ.Otú ọ dị, ka ọnụ ọgụgụ na oge nke mbuze na-abawanye, mgbawa na-aga n'ihu na-amụba na olu nke alum guzobere na-abawanye, na-akpata extrusion cracks.N'ikpeazụ, ifriizi-agbaze na ikpughe sulfate ga-ebelata ike nke kọlụm.