颗粒状炉渣掺量对加气混凝土砌块性能的影响

Effect of granular furnace slag content on the performance of aerated concrete blocks

为了研究颗粒状炉渣掺量对加气混凝土砌块(PT砌块)性能的影响,测试其扩散度、出釜干密度及抗压强度,通过XRD、SEM和孔结构分析揭示其机理。研究表明,随着颗粒状炉渣掺量的增大,PT砌块的扩散度增大,干密度先减小后增大。当掺量小于20%时,颗粒状炉渣起到晶核作用,水化空间增大,水化更充分,托勃莫来石和C-S-H产物的增加对强度起主导作用,抗压强度增大;当掺量为20%~30%时,浆体扩散度较高,浆体的稠化速度小于发气速度,浆体表面大量冒泡,均匀的孔结构遭到破坏,抗压强度降低;当掺量超过30%时,浆体发生塌模,干密度增大,抗压强度提高。当颗粒状炉渣掺量为20%时,PT砌块的抗压强度为5.61 MPa,干密度605 kg/m^(3),满足GB/T 11968—2020《蒸压加气混凝土砌块》中A5.0、B06的要求。

In order to study the effect of granular furnace slag content on the performance of aerated concrete blocks(PT blocks),the diffusion degree,dry density and compressive strength of PT blocks were tested.The mechanism was revealed by XRD,SEM and pore structure analysis methods.The study showed that with the increase of granular furnace slag content,the diffusion degree of PT blocks increased,and the dry density first decreased and then increased.When the content was less than 20%,the granular furnace slag acted as a crystal nucleus,the hydration space increased,and the hydration was more completely.The increase of tobermorite and C-S-H products play a leading role in the strength,and the compressive strength increased.When the content was in the range from 20%to 30%,the mortar diffusion degree was high,the thickening speed of the mortar was less than the gassing speed,resulting in a large number of bubbles on the surface of the mortar,the uniform pore structure was damaged,and the compressive strength decreased.When the content was more than 30%,The mortar collapses,the dry density increased and the compressive strength increased.The compressive strength and dry density of PT block with 20%granular furnace slag was 5.61 MPa and 605 kg/m^(3) respectively,which met the requirement of A5.0,B06 in the national standard"Autoclaved Aerated Concrete Block"GB/T 11968—2020.