Superplasticizer

Admixtures uas tuaj yeem txo cov dej sib tov zoo nyob rau hauv cov xwm txheej uas cov slump ntawm pob zeb yog qhov zoo ib yam yog hu ua superplasticizers.

Ib qho kev sib xyaw uas tuaj yeem txo cov dej sib tov los ntawm ntau dua 15 feem pua ​​​​thaum qhov poob ntawm cov pob zeb yog qhov zoo ib yam.

——Quoted los ntawm DL/T5100-2014 "Technical Specifications for Hydraulic Concrete Admixtures"

high range dej txo admixture

Keeb kwm kev loj hlob

Thawj tiam ntawm superplasticizers-naphthalene-based superplasticizers thiab melamine resin-based superplasticizers tau tsim nyob rau xyoo 1960s. Vim lawv qhov kev ua tau zoo dua li cov superplasticizers zoo tib yam, lawv tau tsim nyob rau xyoo 1930s lig. Lignin sulfonate yog tus sawv cev - muaj kev txhim kho tseem ceeb, yog li nws tseem hu ua superplasticizer. Qhov thib ob tiam ntawm superplasticizers yog sulfamate, txawm hais tias nyob rau hauv raws sij hawm nws yog tom qab lub thib peb tiam ntawm superplasticizers - polycarboxylate. Cov graft copolymer nrog ob pawg sulfonic acid thiab pawg carboxylic acid yog qhov tseem ceeb tshaj plaws thiab kev ua tau zoo tshaj plaws superplasticizer hauv peb tiam superplasticizer.

hom tsiaj loj

Cov dej-txo tus nqi ntawm superplasticizer tuaj yeem ncav cuag ntau dua 20 feem pua. Feem ntau yog naphthalene series, melamine series thiab dej txo cov neeg ua haujlwm sib xyaw ua ke los ntawm lawv, ntawm cov naphthalene series yog cov tseem ceeb, suav txog 67 feem pua. Tshwj xeeb tshaj yog nyob rau hauv kuv lub teb chaws, feem ntau ntawm cov superplasticizers yog naphthalene-based superplasticizers nrog naphthalene ua cov khoom tseem ceeb. Naphthalene-based superplasticizers tuaj yeem muab faib ua cov khoom siv siab (Na2SO4 cov ntsiab lus<3%), medium-concentration="" products="" na2so4="" content="" to="" and="" low-concentration="" according="" the="" of="" in="" their="" products.="">10 feem pua). Feem ntau cov naphthalene-based superplasticizer synthesis cov nroj tsuag muaj peev xwm tswj tau cov Na2SO4 cov ntsiab lus hauv qab 3 feem pua, thiab qee qhov kev lag luam siab heev tuaj yeem tswj tau qis dua 0.4 feem pua.

Naphthalene-raws li superplasticizers yog cov khoom siv tau zoo tshaj plaws thiab siv dav siv cov khoom siv hluav taws xob zoo hauv kuv lub teb chaws (sau ntau dua 70 feem pua ​​​​ntawm cov nyiaj superplasticizers). , tsis tshua muaj kev cuam tshuam rau lub sijhawm teem, kuj zoo adaptability rau cov cement, tuaj yeem siv ua ke nrog ntau yam khoom siv, thiab tus nqi kuj pheej yig. Naphthalene-raws li dej-txo admixtures feem ntau yog siv los tsim cov dej fluidity, siab zog, thiab kev ua haujlwm siab. Kev poob qis ntawm cov pob zeb yooj yim sib xyaw nrog naphthalene dej txo tus neeg sawv cev sai dua. Tsis tas li ntawd, kev hloov pauv ntawm naphthalene-based superplasticizers rau qee cov cements yuav tsum tau txhim kho.

yam ntxwv

Superplasticizer muaj cov nyhuv dispersing zoo ntawm cov cement, uas tuaj yeem txhim kho cov dej ntws ntawm cov cement sib tov thiab cov pob zeb ua pob zeb, thaum txo cov dej haus thiab txhim kho kev ua haujlwm zoo. Txawm li cas los xij, qee qhov superplasticizers yuav ua kom cov pob zeb poob qis, thiab yog tias qhov ntau npaum li cas, nws yuav ua rau los ntshav. Superplasticizer yeej tsis hloov lub sijhawm teem ntawm pob zeb. Thaum noj ntau npaum li cas (overdosage), nws muaj qhov teeb tsa me ntsis retardation nyhuv, tab sis nws tsis ncua kev loj hlob ntawm lub zog thaum ntxov ntawm cov pob zeb hardened.

Nws tuaj yeem txo cov dej haus zoo heev thiab txhim kho lub zog ntawm pob zeb txhua hnub. Thaum ua kom lub zog tas li, cov cement txuag ntawm 10 feem pua ​​lossis ntau dua tuaj yeem ua tiav.

Cov ntsiab lus chloride ion tsawg heev, thiab nws tsis corrode steel bar. Nws tuaj yeem txhim kho qhov impermeability, khov-thaw tsis kam thiab corrosion kuj ntawm cov pob zeb, thiab txhim kho lub durability ntawm pob zeb.

Scope ntawm daim ntawv thov

Nws yog tsim rau prefabricated thiab cam khwb cia-nyob rau hauv-qhov chaw reinforced pob zeb nyob rau hauv ntau yam kev lag luam thiab pej xeem kev tsim kho, kev txuag dej, kev thauj mus los, chaw nres nkoj, nroog thiab lwm yam dej num.

Nws yog tsim rau high-strength, ultra-high-strength thiab nruab nrab-lub zog pob zeb, nrog rau cov pob zeb uas yuav tsum tau muaj zog thaum ntxov, nruab nrab Frost tsis kam thiab siab fluidity.

Precast qhob cov ntsiab lus tsim nyog rau cov txheej txheem ua kom sov.

Nws yog qhov tsim nyog rau cov dej-txo cov khoom siv ntxiv (piv txwv li masterbatch) ntawm ntau cov khoom sib xyaw ua ke.

kev txawj ntse

Cov txheej txheem kev cai rau superplasticizers thiab retarding superplasticizers yog teev nyob rau hauv "Concrete Admixtures" (GB8076-2008).