粉煤灰基地聚合物拉伸性能研究

以粉煤灰为主要原材料,矿粉为添加剂,水玻璃和氢氧化钠为激发剂,制备地聚合物。通过正交试验测试了水胶比(W)、碱激发剂掺量(S)、矿粉取代率(B)和水玻璃模数(M)在不同水平下的地聚合物试样3 d、7 d与28 d的拉伸强度。通过极差分析和因素指标分析,得出各因素对拉伸强度的影响规律。当水胶比为0.3,碱激发剂掺量为0.08,矿粉取代率为0.3,水玻璃模数为1.8,试样的各龄期拉伸强度较优,可得到3 d、7 d和28 d拉伸强度为1.65 MPa、2.25 MPa和3.68 MPa的地聚合物胶凝材料。通过X射线衍射(XRD)和扫描电镜(SEM)对拉伸性能进行了机理分析。分析结果表明,拉伸强度与无定型凝胶体的含量和产物微观形貌相关。

Study on the Tensile Properties of Fly Ash-Based Geopolymers

Fly ash as the raw material, blast furnace slag as the additives, sodium silicate and sodium hydroxide as activators, a kind of fly ash-based geopolymers was made. The effect of water to binder ratio (W), alkali-activator proportion (S), blast furnace slag replacement ratio (B) and the module of sodium silicate (M) at different ratio on the 3d, 7d and 28d tensile strength of geopolymer samples were researched by the orthogonal test. The influence rules of factors on tensile strength were investigated by range analysis and factor analysis. The best tensile strength of samples cured for 3d, 7d and 28d were 1.65, 2.25 and 3.68 MPa. The mechanism of tensile properties was analyzed by XRD and SEM test. The analysis results showed that the tensile strength related to the content of the amorphous gel and microcosmic morphology.