改性矿渣水泥-渣土免烧砖的制备与性能表征

以改性矿渣水泥为渣土固化的胶凝材料制备了性能稳定的免烧渣土砖,研究了改性矿渣水泥与渣土的质量比(胶渣比)对免烧渣土砖抗压强度、吸水率、软化系数、冻融循环稳定性、干湿循环稳定性的影响,分析了免烧渣土砖的固化机制。结果表明:胶渣比为1∶4时所制备的免烧渣土砖抗压强度和软化系数最高,分别为15.81 MPa和0.80;吸水率和15次干湿循环后的质量损失率最小,分别为8.12%和0.61%。XRD和SEM分析显示,改性矿渣水泥和水掺入渣土后(经过均匀混合和高压成型),反应物的水化速度加快,使渣土材料快速硬化,获得较高的早期强度。

Preparation and characterization of sintering-free bricks based on modified slag cement&muck

Sintering-free muck brick(SFB)with high physical performances have been prepared using modified slag cement as cementing materials.The effects of the ratio of modified slag cement to muck(ratio of B/M)on the properties of the as-prepared SFB specimens were investigated,which included the compressive strength,water absorption and softening coefficient as well as the stability of the freeze-thaw cycles and stability of the drying and wetting cycles(DWC).The solidified mechanism for the SFB was also analyzed.The results showed that the resulting SFB specimen with a ratio of B/M being 1∶4 had the highest values of 15.81 MPa and 0.80 for the compressive strength and softening coefficient,respectively.Also,the lowest values of 8.12%and 0.61%for the water absorption and the mass loss ratio after 15 times DWC were obtained for the above mentioned specimen.The XRD and SEM analyses of the resulting SFB specimen indicated that in the mixture of modified slag cement,muck and water,the hydro-reaction speed was accelerated,the rapid hardening was realized and therefore the higher early strength was improved after high pres-sure compact-forming due to the addition of modified slag cement.