钢渣对硬化水泥浆体结构形成的影响研究

研究了钢渣对水泥强度及体积膨胀率的影响,采用SEM和EDXA分析了水化产物的形貌和微区化学成分,并用XRD对水化产物的矿物组成进行了分析研究。研究结果表明,钢渣的掺入会降低水泥净浆的早期抗压强度,但随钢渣水化的进行,掺钢渣的水泥浆体7d以后的强度增长较快,至120d时净浆抗压强度已与纯硅酸盐水泥相近。掺钢渣的水泥的体积膨胀率比纯硅酸盐水泥的体积膨胀率大,钢渣水泥的体积膨胀率主要取决于钢渣中的fCaO含量。掺钢渣水泥的主要水化产物组成和形貌与纯硅酸盐水泥无明显差别,所不同的是C-S-H凝胶中有较多的铁相。掺钢渣水泥的水化产物主要有C2SH(C)、AFt和Ca(OH)2。

Study on effects of steel slag on structure formation of hardened cement paste

The strength and expansion ratio of hardened blended cement paste mixed with steel slag were studied. The appearance of hydration production and its chemical composition were analyzed with SEM and EDXA. The mineral compositions of the hydration production were detected with XRD. The results showed that the early strength of hardened blended cement paste could be decreased with the increase of steel slag. But the strength of hardened blended cement paste at 120d was nearly close to that of pure Portland cement because of the faster development of the strength after 7d, its volume expansion ratio will fluctuate with the variation of the free lime content in steel slag. The appearance of hydration production and its mineral composition in the hardened blended cement paste were almost the same with that of the pure Portland cement. The difference was there were more Fe phase in hardened blended cement paste than in pure Portland cement. The main hydration production were C2SH(C), AFt and Ca(OH)2 in hardened blended cement paste mixed with steel slag.