碱渣含量和蒸压加气参数对建筑混凝土抗压强度的影响

Influence of Alkali Residue Content and Autoclaved Aeration Parameters on Compressive Strength of Building Concrete

利用碱渣来作为蒸压加气混凝土的原料,实验测试研究碱渣含量和蒸压加气参数对建筑混凝土抗压强度的影响。研究结果表明:当碱渣的加入量由0%逐渐上升至30%时,得到的AAC试样密度介于692~703kg·m^(-3)范围内,抗压强度发生了先上升后降低的变化趋势。当蒸压压力上升后,AAC试样发生了抗压强度先增大后降低的变化趋势,密度发生了先下降后上升的变化规律。当蒸压时间增加后,AAC发生了抗压强度先上升后下降的现象,而密度保持基本稳定。在AAC试样XRD谱图上形成了CSH非晶态凝胶的弥散峰、托贝莫来石结晶峰以及CSH半结晶峰。水化产物由半结晶CSH与托贝莫来石组成,这些水化产物以相互交错的形式连接,具有明显的骨架层次,使AAC试样获得更高的强度。

The influence of alkali residue content and autoclaved aeration parameters on compressive strength of building concrete was studied by using alkali residue as raw material of autoclaved aerated concrete.The results showed that the density of AAC sample was within the range of 692~703 kg·m^(-3),and the compressive strength first increased and then decreased when the addition of alkali residue increased from 0% to 30%.After the rise of the autoclaved pressure,the compressive strength of AAC sample showed a trend of increasing first and then decreasing,and the density showed a trend of decreasing first and then increasing.When the autoclaved time increased,the compressive strength of AAC increased first and then decreased,while the density remained basically stable.The dispersion peak of CSH amorphous gel,the crystal peak of tobermorite and the semi-crystal peak of CSH were formed in the XRD spectra of AAC samples.The hydration products were composed of semi-crystalline CSH and tobermorite.These hydration products were connected with each other in a staggered form and had obvious skeleton hierarchy,which made the AAC sample obtain higher strength.