碱渣-粉煤灰基新型注浆材料耐久性试验研究

EXPERIMENTAL RESEARCH ON DURABILITY OF NEW GROUTING MATERIALS WITH SODA RESIDUE AND FLY ASH MATRIX

利用碱渣、粉煤灰和硅酸钠溶液制成新型采空区充填注浆材料,采用9组正交试验试样探索该注浆材料抗压强度发展特性、耐酸性和碱性渗出特性。结果表明：该新型注浆材料抗压强度具有显著的龄期效应。该注浆材料的碱性渗出是快速的,对局部环境的影响较大,建议工程应用时与易受腐蚀构造保持一定安全距离。9组独立的正交试验试样受5%质量分数的盐酸溶液侵蚀后,质量损失在4.2%~6.2%,抗压强度损失在2~8 MPa。受盐酸侵蚀过程中有CO_2和硅胶的生成减小了质量和强度。粉煤灰受碱激发生成的硅铝酸盐聚合物凝胶（N-A-S-H）一定程度上阻止了盐酸对试样的深化侵蚀。

Soda residue,fly ash and sodium silicate solution were mixed to synthesize as new grouting materials for filling goaf. 9 groups of samples from orthogonal test were designed to explore the development of compressive strength,alkaline exudation and acid resistance. The results showed that the compressive strengths of samples had a significant age effect. The alkaline exudations of grouting materials were rapid which had a great impact on the local environment. It was suggested that a safe distance should be kept from the structures susceptible to corrosion for their engineering application. The 9 groups of independent samples were attacked by 5% hydrochloric acid solution,and the mass loss was 4. 2% ~ 6. 2% and the compressive strength loss was 2 ~ 8 MPa. During the corrosion process,the mass and compressive strength were reduced due to the formations of CO_2 and silica gel. The aluminosilicate polymer gel（ N-A-S-H） generated from alkali-activated fly ash could prevent the deep corrosion of hydrochloric acid from the samples to some extent.