摘要
用化学纯的NaCl、NaOH、KCl、KOH来调整水泥中当量碱含量达到1.0%,采用砂浆棒法快速判定集料的潜在碱活性;用粉煤灰和磨细矿渣粉等量取代部分硅酸盐水泥,并评价这两类矿物掺合料对抑制碱-硅酸反应的效用。试验结果表明,用分子量比值作为当量碱计算的权值得到的当量碱,不能真正反映混凝土中总碱量与ASR膨胀率之间的规律;相同掺量条件下,粉煤灰抑制ASR的作用显著优于磨细矿渣粉;为有效避免混凝土发生ASR,并尽量满足混凝土的其他性能,可采取水泥∶磨细矿渣粉∶粉煤灰=40∶40∶20的胶凝材料体系。
Equivalent alkali content(1.0%) of cement adjusted with NaCl,NaOH,KCl,KOH che mically pure is used to determine the potential alkali activity of some aggregate through Accelerated Mortar Bar Test(AMBT).The alkali-silicate reaction(ASR) inhibition effects of fly ash and GGBS are evaluated by replacing equal content of Portland cement in the test.The results shown:(1) the weight calculated by molecular weight ratio should not be simply used to compute the equivalent alkali content which can t fully represent the relationship between the whole alkali content and ASR expansion; (2) the effects of fly ash on inhibiting ASR is much better than that of GGBS; (3) the cementitious materials component ratio such as cement " GGBS " fly ash=40 : 40 : 20 is appropriate for inhibiting ASR and some other perfor-mances of fresh and hardened concrete.
出处
《公路》
北大核心
2009年第9期151-155,共5页
Highway
关键词
碱-硅酸反应
当量碱
矿物掺合料
抑制作用
试验研究
alkali-silicate reaction
equivalent alkali
mineral admixtures
inhibition effect
test and research