混凝土
混凝土
혼응토
CONCRETE
2014年
2期
82-84,87
,共4页
薛斌%薛邵龙%尹凌云%盛燕萍
薛斌%薛邵龍%尹凌雲%盛燕萍
설빈%설소룡%윤릉운%성연평
无碱液态速凝剂%喷射混凝土%微观结构%促凝机理
無堿液態速凝劑%噴射混凝土%微觀結構%促凝機理
무감액태속응제%분사혼응토%미관결구%촉응궤리
liquid alkali-free setting accelerator%sprayed concrete%microcosmic structure%acceleration mechanism
介绍了一种新型无碱液态速凝剂的合成方法,并采用宏微观试验对其性能及作用机理进行研究。结果表明:当速凝剂掺量为8%时,可使P·O 42.5级水泥的初凝时间和终凝时间缩短至180、410 s,1 d抗压强度达到23.4 MPa,比空白样提高了36.2%,28 d抗压强度保有率达到了110%;速凝剂对材料温度变化不敏感,其在低温下仍具有良好的促凝效果;但增大了水泥砂浆的收缩,需对其合理养护;通过SEM测试手段分析了其促凝机理:在早期水泥浆体水化过程中,形成大量的钙矾石晶体,晶体间相互搭接,形成空间骨架结构,导致水泥浆体迅速凝结。
介紹瞭一種新型無堿液態速凝劑的閤成方法,併採用宏微觀試驗對其性能及作用機理進行研究。結果錶明:噹速凝劑摻量為8%時,可使P·O 42.5級水泥的初凝時間和終凝時間縮短至180、410 s,1 d抗壓彊度達到23.4 MPa,比空白樣提高瞭36.2%,28 d抗壓彊度保有率達到瞭110%;速凝劑對材料溫度變化不敏感,其在低溫下仍具有良好的促凝效果;但增大瞭水泥砂漿的收縮,需對其閤理養護;通過SEM測試手段分析瞭其促凝機理:在早期水泥漿體水化過程中,形成大量的鈣礬石晶體,晶體間相互搭接,形成空間骨架結構,導緻水泥漿體迅速凝結。
개소료일충신형무감액태속응제적합성방법,병채용굉미관시험대기성능급작용궤리진행연구。결과표명:당속응제참량위8%시,가사P·O 42.5급수니적초응시간화종응시간축단지180、410 s,1 d항압강도체도23.4 MPa,비공백양제고료36.2%,28 d항압강도보유솔체도료110%;속응제대재료온도변화불민감,기재저온하잉구유량호적촉응효과;단증대료수니사장적수축,수대기합리양호;통과SEM측시수단분석료기촉응궤리:재조기수니장체수화과정중,형성대량적개반석정체,정체간상호탑접,형성공간골가결구,도치수니장체신속응결。
Presented a alkali-free liquid setting accelerator and properties of the production process such as technical characteristics.Re-sults of property test showed that 8%alkali-free liquid setting accelerator addition could shorten initial setting time and final setting time of P·O 42.5 to 180 s and 410 s respectively,made 1 d compressive strength attain to 23.4 MPa which was 36.2%higher than that of blank specimen,retaining rate of 28 days compressive strength reach 110%.The setting accelerator is insensitive to the change of material temper-ature,had good accelerate effect in low temperature,but increased the shrinkage of cement paste,and need appropriate maintenances.The acceleration mechanism was analysised through the test method of SEM.At the beginning hydration ,the cement paste with liquid setting accelerator produced a mass of clubbed ettringite crystal,the overlap between the crystal forms the space frame structure,which is the main reason of improving the cement paste setting.