某水库混凝土配合比试验中碱骨料反应抑制措施有效性分析

Effectiveness Analysis of Alkali-aggregate Reaction Inhibition Measures in Concrete Mix Ratio Test of a Reservoir

针对某水库工程混凝土配合比试验中所用工地骨料经试验检测为有潜在危害性的碱活性骨料,为防止碱骨料反应危害,着重开展了碱骨料反应抑制措施有效性试验。工程需要显示,这一试验方案需设计8个,分别考虑单掺粉煤灰、外加剂以及粉煤灰与外加剂混掺对骨料碱活性的抑制作用。具体试验结果包括这两大类各有14种情况,依据规程规定:对比试件28 d龄期膨胀率小于0.10%,则碱骨料反应危害抑制效果评定为有效。鼓楼水泥和西南水泥单掺25%、35%、45%、55%和65%粉煤灰以及混掺同样比例类型的粉煤灰加减水剂、引气剂28 d膨胀率均小于0.10%,有10种情况均可评为有效。此分析研究结果可为水库工程设计、施工等提供参考依据。

The site aggregate used in the concrete mix ratio test of a reservoir project has been tested as alkali active aggregate with potential harm,in order to prevent alkali aggregate reaction harm,the effectiveness test of alkali aggregate reaction inhibition measures was emphatically carried out.The results show that there are 8 effective schemes for the design of alkali-aggregate reaction inhibition measures,which respectively consider the inhibition effect of single fly ash,admixture and the mixture of fly ash and admixture on the alkali-aggregate activity.The specific test results include 14 results in each of the two categories.According to the provisions of the Test Code for Alkali Aggregates of Hydraulic Concrete,if the expansion rate of the 28-day age contrast specimen is less than 0.10%,the inhibition effect of alkali-aggregate reaction hazard is evaluated as effective.The expansion rate of Gulou Cement and Southwest Cement after 28d mixing with 25%,35%,45%,55%and 65%fly ash and the same proportion of fly ash plus water reducer and water diversion agent is less than 0.10%.There are 10 cases that can be evaluated as effective.The results can provide the reference for the design and construction of reservoir engineering.