SH材料加固夯筑遗址土耐久性试验及机理研究

以添加SH材料加固的明长城古浪段夯筑遗址土为研究对象，对其重塑样进行紫外老化试验、冻融循环试验及耐盐、耐碱试验，研究其力学强度特征及耐久性能，并采用扫描电镜（SEM）、EDS能谱分析以及粒度分析研究SH材料加固夯筑遗址土的机理。试验结果表明，经紫外老化的SH固化后试样的无侧限抗压强度随老化时间增长呈先增后降，SH含量高的试样强度呈一直增长的趋势；随着冻融循环次数的增加，试样的无侧限抗压强度逐渐降低，质量损失率逐渐增加，其中SH固含量为0.8%的试样表现出极好的耐冻性能；相比素土，加固后的试样耐盐、耐碱性能明显有所提高。由机理分析得出，SH材料主要通过团聚、氢键、架桥和包裹等作用使土颗粒排列紧密、增强连接性，提高了遗址土的各种性能；SH材料加固夯筑遗址土具有良好的耐久性能。

Durability test and reinforced mechanism on adding SH materials into soil of archaeological sites

Taking the soil of the Great Wall of Ming Dynasty at Gulang segment as the research object, its mechanical strength and durability are studied by adding polymer material SH into remodeling samples under ultraviolet aging, freeze-thaw cycle, and salt and alkali resistant tests. In addition, scanning electronic microscope(SEM), energy dispersive spectrum(EDS) analysis and grain size analysis are used to study the mechanism of rammed earthen sites reinforced by SH material. The results show that the unconfined compressive strength of the solidified sample after ultraviolet aging test often increased at first and then decreased with the aging time. However, when the solid content of SH is very high in the remodeling samples, the strength of reinforced sample showes continuous increase trend after UV-aged tests. With the increase in cycling of freeze-thaw test, the unconfined compressive strength of the sample gradually decreases, and the mass loss rate gradually increases. The sample with SH solid content of 0.8% shows excellent frost resistance performance. Compared with raw soil, the salt and alkali resistant performance of samples reinforced by SH materials are improved obviously. SH materials mainly make the soil particles closely arranged and strengthen the connectivity through agglomeration, hydrogen bonding, bridging and wrapping. Thus it improves various properties of the soil at archaeological sites. which has good durability.