Hnub Kawg: 16 Lub Ib Hlis, 2023

Concrete additives yog cov tshuaj thiab cov khoom sib xyaw rau hauv cov cement los hloov nws cov kev ua tau zoo. Cov khoom siv ntxiv muab cov txiaj ntsig tshwj xeeb rau ib txoj haujlwm tshwj xeeb. Cov kua dej ntxiv siv thaum lub sij hawm sib tsoo cement txhim kho lub zog ntawm cov cement. Kev sib koom ua ke ntawm cov khoom sib txuas ua rau cov pob zeb qub qub rau cov tshiab rau kev ua haujlwm sab hauv thiab sab nrauv xws li phab ntsa capping thiab resurfacing. Xim additives muab cov pob zeb ua kom zoo nkauj. Txawm li cas los xij, cov khoom siv ua vaj tse ntxiv pab ua kom tiav.

Cov huab cua txias pob zeb muaj cov khoom zoo tshaj plaws rau cov pob zeb tso rau hauv huab cua kub. Txawm li cas los xij, thaum qhov kub thiab txias, cov pob zeb ua kom muaj zog qeeb dua vim tias cov cement tsis hydrate sai. Teem sijhawm yog nce li ib feem peb rau txhua 10 degree txo qis hauv pob zeb kub mus rau 40 degrees Fahrenheit. Accelerating admixtures tuaj yeem pab daws cov teebmeem no ntawm qhov kub qis ntawm qhov chaw thiab lub zog nce. Lawv yuav tsum ua tau raws li qhov yuav tsum tau ua ntawm ASTM C 494, Standard Specifications for Chemical Admixtures for Concrete.

Jufu muab cov khoom ua vaj tse ntxiv rau huab cua txias thiab cov khoom siv ntxiv rau cov dej tsis muaj dej, uas tuaj yeem siv dav hauv Kev Tsim Kho.

Dab tsi yog qhov zoo ntawm cov pob zeb zoo nkauj

1. Raws li cov ntaub ntawv zoo li no muaj compactness zoo thiab ruaj khov dua thaum lub sij hawm tsim kho, cov khoom siv tau zoo heev. Qhov tseem ceeb yog tsis txhob vibrate nyob rau hauv cov txheej txheem ntau lawm, uas txo lub sij hawm pouring thiab ua hauj lwm hnyav, thiab kuj txo cov nqi zog.

2. Raws li tau hais dhau los, vim tias tsis tas yuav muaj kev vibration, tsis muaj suab nrov, thiab tib neeg txhais tes tuaj yeem so, uas ua rau muaj kev nyab xeeb ntawm kev ua haujlwm thiab txhim kho kev ua haujlwm.

3. Los ntawm kev xav ntawm kev tsim kho zoo, yuav tsis muaj npuas ntawm qhov chaw tsim kho thaum siv cov khoom no, cia nyob ib leeg kho. Nyob rau tib lub sijhawm, nws cov qib ntawm kev ywj pheej yog siab heev, txawm tias qee qhov nyuaj heev los yog cov qauv uas muaj qhov ntom ntom ntom ntom ntom tuaj yeem yooj yim nchuav.

Dab tsi yog qhov ceev faj rau kev sib xyaw ua ke:

1. Cov tswv tsev sib xyaw ua ke nyob rau hauv cov ntawv sau sib txawv yog qhov sib txawv, tsis tsuas yog, tab sis kuj nyob ntawm hom khoom tshwj xeeb, thiaj li xaiv cov khoom xyaw thiab cov khoom tsim nyog.

2. Kev siv ib lub chaw nres tsheb lossis ob lub chaw nres tsheb yog nyob ntawm cov haujlwm tshwj xeeb. Yog hais tias ib tug loj npaum li cas ntawm cov pob zeb yuav tsum tau poured nyob rau hauv ib lub sij hawm thiab qhov yuav tsum tau rau nws cov zoo yog kuj siab, nws yog zoo dua los siv ob pawg me me sib tov nroj tsuag.