垃圾焚烧灰和矿粉对混凝土脆性和抗裂性的影响

摘要

Based on C30 pumping concrete mix, slag and waste incineration ash individually or intermixed may be used as admixture to prepare concrete. Basic construction performance such as setting time, slump and slump loss can be determinated. According to tension strength and compression strength ratio of concrete system, its brittleness can be discussed. By plate method, inlfuence of slag or waste incineration ash on early cracking of concrete may be studied. The results can show that: waste incineration ash as a single admixture, its inlfuence on concrete performance especially early cracking resistance can be poor. But when waste incineration ash and slag with superior activity may be used together as composite admixture, crack resistance of the corresponding concrete can be obviously improved, and its compressive strength can reach C30 strength design requirements.%基于实际工程常用的C30泵送混凝土配比，利用矿粉、垃圾焚烧灰以单掺、复配的方式替代水泥后配制掺合料混凝土。测定其凝结时间、坍落度和坍落度经时损失等基本施工性能，并根据各体系混凝土的拉压比分析其脆性，同时利用平板法研究矿粉、垃圾焚烧灰对混凝土早期开裂的影响规律，结果表明，垃圾焚烧灰作为单一掺合料时，对混凝土的性能尤其是早期抗开裂性能影响不利，但在与高活性矿粉的复合使用时，所配制的掺合料混凝土抗裂性能明显得到改善，并且其抗压强度仍能达到C30的强度设计要求。