烧结法赤泥复合改性路用性能研究

Experimental Study on Road Performance of Sintered Red Mud by Compound Modification

摘要: 本文采用脱碱剂、水泥与生石灰对烧结法赤泥进行了复合改性。对不同配合比下的烧结法赤泥击实特性、脱碱性和无侧限抗压强度进行了室内试验研究，评价了复合改性烧结法赤泥的路用性能与环境影响。试验结果表明，与单掺脱碱剂改性的烧结法赤泥相比，复合改性烧结法赤泥的最佳含水率降低4%~6%，最大干密度提高0.01~0.015 g/cm3。相较于生石灰，水泥对烧结法赤泥的击实性能、PH值、无侧限抗压强度的影响更为显著。根据IV类地下水PH值低于9.0的限值，优化复合改性剂配比为：4%脱碱剂 + 4%水泥 + 2%石灰。复合改性后烧结法赤泥的无侧限抗压强度在1.2 MPa以上，满足高速公路路床区填料的强度要求。

Abstract: This paper introduced the dealkalization agent, cement and quicklime to modify sintered red mud. The compaction characteristics, alkalinity and unconfined compressive strength of the sintered red mud at different mix proportions were studied, and the road performance and en-vironmental impact were evaluated. Results showed that, compared with the sintered red mud modified by dealkalization agent only, the optimum moisture contents of the compound modi-fied red mud reduced by 4%~6%, and the maximum dry density increased by 0.01~0.015 g/cm3. Cement had more significant effects on compaction performance, PH value and unconfined compressive strength than quicklime. According to the specification of class IV groundwater, i.e., PH value ≤ 9.0, the optimal mix proportion of the compound modified red mud was proposed as 4% dealkalization agent, 4% cement and 2% quicklime. The unconfined compressive strength of the compound modified red mud increased to more than 1.2 MPa, which met the strength re-quirement of the roadbed filling in highway.