免烧淤泥砖的力学性能与微观结构

Mechanical Properties and Microstructure of Non-calcination Sludge Brick

基于石灰激发淤泥中SiO2和Al2O3活性组分以产生胶凝产物的原理,在蒸养条件下制备了免烧淤泥砖.系统研究了不同掺量(质量分数)的粉煤灰(10%～50%)和水泥(5%～20%)对石灰-淤泥胶凝体系力学性能的影响规律,并通过压汞法、扫描电镜、X射线衍射仪、超声波分析了免烧淤泥砖的微观结构和早期结构形成过程.结果表明:石灰的最佳掺量为30%;水泥掺量为20%时坯体强度较纯坯体(不掺外掺料)提高约50%;单掺粉煤灰(最佳掺量30%)可显著改善免烧淤泥砖坯体的力学性能、细化孔径,提高坯体密实度.

Based on lime simulating active component（SiOz and A1203） of the sludge theory, non-calcination sludge brick was prepared in the saturated steam environment. The mechanical properties of limesludge system with incorporation of fly ash（ 10 %-50 %） and cement（5 %-20 % ） were systematically investigated. Mercury intrusion measurements, scanning electron microscopy, X-ray diffraction and ultrasonic pulse velocities were also used to measure the characteristic and evolution of microstructure. The experi- mental results show that the strength of brick with 30% lime and 20% cement increases by 50% than the one of pure brick. In addition, brick with 30% fly ash improves the mechanic properties, and reduces pore size and porosity.