黏度时变水泥稳定碎石材料抗冻性能试验研究

为研究水泥稳定碎石材料在高寒山区的路用性能,选用自主研发的黏度时变(SJP)浆材作为水泥稳定碎石材料的胶结材料,采用无侧限抗压强度试验、冻融循环试验研究SJP水稳材料的力学性能,并结合电镜扫描(SEM)方法讨论SJP水稳材料的抗冻融机理。研究结果表明:SJP水稳材料较普通水稳材料早期强度增长快、后期强度略高,SJP助剂可以降低材料冻融后的质量损失率,提高其抗冻系数; SJP浆液在助剂的作用下,C-S-H增多与纤维状水化衍生物相结合,黏结力提高使得骨料结合更加紧密,从而有效地减缓水稳材料在冻融条件下损伤的积累,提高了道路基层的耐久性能。研究结果为提高高寒地区早期强度、减少在大温差条件下裂缝产生的路基材料选用提供了参考。

Mechanical Properties and Frost Resistance of Cement-stabilized Clastic Rock Material with Time-varying Paste Viscosity

The aim of this study is to investigate the performance of cement-stabilized clastic rock material used for road in high and cold mountainous region. Self-developed slurry with time-varying viscosity (SJP) was selected as the cementitious material for the cement-stabilized clastic rock material. Unconfined compression test and cyclic freezing-thawing test were performed to examine the mechanical properties of the SJP-stabilized material, and SEM scanning for the frost resistance. Results demonstrate that the SJP-stabilized material has faster early strength growth and higher later strength than ordinary material. SJP reduces the mass loss rate of material after cyclic freezing and thawing, and improves the frost resistance coefficient. With the aid of SJP, the combination between C-S-H and fibrous hydration products strengthens, hence enhancing the bonding force and making the aggregates bond more closely, effectively decelerating the accumulation of damage of water-stable materials under freezing-thawing conditions and improving the durability of road base.