碱矿渣改良风积砂强度及抗侵蚀性能研究

Study on the Strength and Erosion Resistance of Aeolian Sand Improved by Alkali Slag

为研究碱矿渣改良风积砂强度及抗侵蚀性能,采用正交试验设计方法,对不同配合比试件进行抗压试验及抗硫酸盐侵蚀试验。结果表明,碱矿渣改良风积砂早期强度高,7 d抗压强度可达28 d强度的77%左右,对固砂强度影响最显著的因素为骨胶比,其次为减水剂掺量,最优水平组合:骨胶比为2,碱用量为3.5%,固体质量分数为86%,减水剂用量为0.1%。最优条件下,试件在质量分数为7.5%的Na_2SO_4溶液中浸泡42 d时,无侧限抗压强度达到最大值15.37 MPa,较未浸泡条件下提升33.54%;相对于质量分数为2.5%、7.5%的Na_2SO_4溶液,改良风积砂强度在质量分数5.0%的Na_2SO_4溶液中表现出良好的抗侵蚀性能。

To study the strength and corrosion resistance of aeolian sand improved by alkali slag,the orthogonal test design method was adopted to conduct compression test and sulfate corrosion resistance test on specimens with different mix ratios.The results show that the early strength of aeolian sand improved by alkali slag is high,and the 7 d compressive strength can reach about 77%of the 28 d strength.The most significant factor affecting the strength of sand consolidation is the amount of slag,followed by the amount of water-reducing agent.The optimal conditions are determined that the bone glue ratio is 2,the alkali dosage is 3.5%,the solid content is 86%,and the water-reducing agent dosage is 0.1%.Based on the optimal conditions,the unconfined compressive strength reaches the maximum value of 15.37 MPa when immersed for 42 days under the environmental erosion of 7.5%sulfate,which is 33.54%higher than that under the unsoaked condition.The 2.5%and 7.5%Na2SO4 solution can improve the strength of aeolian sand,and aeolian sand show good corrosion resistance in 5.0%Na2SO4 solution.