【摘要】 为提高粉土的水稳性,采用高分子材料对粉土进行改性。通过室内直剪和单向压缩试验,研究浸水前后改性粉土的抗剪强度和压缩变形特性。研究结果表明:(1)J1–6配比的改性粉土,相比粉土,抗剪强度特性较好;浸水后,PAM凝聚聚合作用减弱,改性粉土强度降低,由于PAM发挥润滑剂的作用,压缩变形量增大;(2)G2–5配比的改性粉土,可提高粉土的抗剪强度,降低粉土的压缩变形量,浸水后,改性粉土所固有的团粒、集粒结构被破坏,表现为强度降低,变形增加,耐水性能差;(3)GJ6–9配比的改性粉土,由于硅酸钠与PAM的共同作用,在粉粒表面形成高分子材料保护层,不仅大幅提高了粉土的黏聚力和内摩擦角,而且具有较好的耐水性能,压缩变形量小。通过该研究,分析改性剂种类、掺量和浸水条件对改性粉土抗剪强度和压缩变形量的影响,确定改性粉土的最佳配比,掌握浸水条件下改性粉土的劣化特性。更多还原

【Abstract】 Silty soil is modified by polymer material from aspects to improve water stability. Indoor direct shear test and unidirectional compression test were conducted to research shearing strength and compressive deformation characteristics before and after submerging. Testing results show that(1) J1–6 proportion silty soil,compared with common silty soil,has a better shearing strength. After submerged,PAM cohesion polymerization decreases,and strength decreases. Compression deformation is great because PAM is capable of playing a role in lubrication.(2) G2–5 proportion silty soil can improve shearing strength at some extent and reduce compression deformation. After submerged,crumb structure and aggregated structure are desctroyed. Decreased strength,increased deformation and bad hydrolytic resistance are showed.(3) Because of combined action of sodium silicate and PAM,GJ6–9 proportion modified silty soil has a high polymer material protection layer on the surface,which greatly improve the cohesion and internal friction angle and also has a better hydrolytic resistance and less deformation. Through the research of effects of modifying agents and its mixture amount as well as submerging conditions on shear strength and compressive deformation,the best proportion is determined and degradation behavior under submerging condition is grasped.更多还原