掺稻壳灰/硅灰混凝土的性能研究

研究了稻壳灰、硅灰、稻壳灰+粉煤灰、硅灰+粉煤灰对混凝土抗压强度、抗折强度、抗硫酸侵蚀能力和抗碳化能力的影响。结果表明:掺加5%~10%稻壳灰或硅灰有助于提升混凝土的抗压强度和抗折强度,且稻壳灰、硅灰掺量越高抗压强度越高,掺硅灰混凝土相对于掺稻壳灰混凝土的抗压和抗折强度更高,掺稻壳灰+粉煤灰、硅灰+粉煤灰试件的抗压和抗折强度低于基准组;稻壳灰相较于硅灰能更好地降低混凝土的干密度,而硅灰相较于稻壳灰能更好地降低试件的吸水率,粉煤灰的摻入会降低试件的干密度,但吸水率明显增加;掺加稻壳灰、硅灰有助于提升试件的抗硫酸侵蚀能力,且硅灰的提升效果优于稻壳灰,掺入粉煤灰后试件的抗硫酸侵蚀能力进一步提高;掺稻壳灰、硅灰试件的抗碳化能力均优于基准组,且硅灰的改善效果优于稻壳灰,而掺入粉煤灰的试件抗碳化性能最差。

Properties of Concrete Mixed with Rice Husk Ash or Silica Fume

The effects of rice husk ash,silica fume,rice husk ash+fly ash,silica fume+fly ash on compressive strength,flexural strength,sulfuric acid resistance and carbonation resistance of concrete were studied.The results show that the addition of 5%~10% rice husk ash or silica fume can improve the compressive strength and flexural strength of concrete,and the higher the content of rice husk ash or silica fume,the greater the compressive strength.The compressive strength and flexural strength of the specimens with rice husk ash+fly ash or silica fume+fly ash are lower than those of blank group.Rice husk ash has a better ability to reduce the dry density of concrete than silica fume,while silica fume has a better role in reducing the water absorption than rice husk ash.The addition of fly ash will reduce the dry density of concrete,but the water absorption is significantly increased.Adding rice husk ash or silica fume can improve the sulfuric acid resistance of concrete,and the improvement effect of silica fume is better than that of rice husk ash,and the sulfuric acid resistance of concrete is further improved after adding fly ash.The carbonation resistance of the specimens with rice husk ash or silica fume is better than that of blank group,and the improvement effect of silica fume is better than that of rice husk ash,while the carbonation resistance of the specimens with fly ash is the worst.