黄河淤积粉土的两种复合稳定方案与性能对比

为探索路基工程中黄河淤积粉土的稳定技术和性能保障方案,针对德州齐河县境内的黄河淤积粉土,在乳化沥青复合稳定粉土(AE稳定土)的研究基础上,采用无机/有机复合材料制备出一种复合固化剂(FG固化剂),研究了AE稳定土和FG稳定土2种稳定方案下粉土的抗压强度性质、水稳定性和抗冻融能力;结合XRD、SEM表征技术,探讨了FG固化剂的稳定机理。研究认为,FG固化剂稳定土较AE稳定土有着更高的无侧限抗压强度、回弹模量和承载能力,水稳定性良好,在抗冻融能力上有着比AE稳定土更好的效果。XRD与SEM分析表明,FG固化剂提供了活性矿物质,其复合胶凝效应和填充增强保障了粉土的抗压强度,高分子物质起到粘结颗粒界面、填塞孔隙的作用,降低了内部孔隙率;两者造成土体的最大干密度变大;与AE稳定土的稳定机理不同。FG固化剂的使用为黄河粉土的稳定和工程应用提供了参考方法。

Composite Stabilization of Silty Soil near the Yellow River:Two Methods and Performance Comparison

Based on the study of emulsified asphalt (AE) composite stabilized silt, we prepared an FG curing agent using inorganic/organic composite materials for the silty soil near the Yellow River in Qihe county. We compared the strength properties, moisture stability and frost resistance between AE-stabilized and FG-stabilized silty soils, and furthermore discussed the stabilizing mechanism of FG curing agent via XRD and SEM. Our findings demonstrated that the silty soil stabilized by FG curing agent had better moisture stability and higher unconfined compressive strength, resilient modulus, bearing capacity, and frost resistance than AE-stabilized soil. XRD and SEM analysis suggest that the composite cementation effect and filling enhancement of the active minerals provided by the FG curing agent guaranteed the strength of the stabilized soil; the polymer material played the role of binding the particle interface and filling the pores, reducing the internal void ratio; and both boosted the maximum dry density of the soil; FG-stabilized soil displayed a different stability mechanism from that of AE-stabilized silt. The use of FG curing agent provides a reference for the stability and engineering application of Yellow River silty soil.