几类传统改性土的工程特性综合评价及在土遗址修复中的应用

Comprehensive evaluation of engineering properties of several kinds of traditional modified soils and their application in the restoration of earthen sites

修复技术是目前土遗址保护领域较为关注的热点问题。基于室内试验、模型试验和层次分析法理论,开展传统改性土的工程特性及在土遗址修复中的适宜性研究。结果表明:(1)在素土中添加一定比例的糯米基、胶凝材料或纤维材料,得到的改性土工程特性均有不同程度的改善,其中,抗剪强度提高为素土的1.3~3.5倍,抗渗性提高为素土的3~1650倍,耐久性提高为素土的1.3~12.5倍;(2)提出基于安全性、耐久性、抗渗性、吸放湿特性、经济性、施工难易性6类指标,来综合评估改性土在土遗址修复中的适宜性,认为糯米灰浆类改性土在土遗址的修复中适宜性较好,石灰、植物纤维等材料改性土的适宜性稍差,水泥改性土不宜在土遗址修复中采用。

The restoration technology of earthen sites is a hot issue in the protection engineering.Based on laboratory test,model test and analytic hierarchy process(AHP)theory,the engineering characteristics of traditional modified soil(MS)and its suitability for earthen sites restoration were studied.The results showed that:(1)the engineering properties of the MS were improved by adding a certain proportion of sticky rice,cementitious material or fiber material to the plain soil(PS).The shear strength,impermeability and durability of PS are increased by 1.3-3.5 times,3-1650 times and 1.3-12.5 times,respectively.(2)Six indexes for comprehensive suitability evaluation of various kinds of MSs during the restoration of earthen sites were put forward,which are the safety,durability,anti-seepage,hygroscopic and desiccant characteristics,economy,construction difficulty.It indicates that the suitability of MS with adding sticky rice and mortar is the better than that of the lime,plant fiber materials.The cement-modified soil should not be used in earthen sites restoration.