新型透明黏土制配及其物理力学特性研究

基于人工合成透明土材料和PIV技术的可视化模型试验方法是重要的岩土工程测试手段之一,然而,目前已有透明土材料中针对模拟天然黏土的材料仍相对较少。提出以Carbopol~ Ultrez10聚合物(简称U10)、NaOH粉末和纯净水为原材料,碳纳米材料掺入作为示踪粒子制成散斑场,制配一种新型透明黏土材料的技术方案与操作方法。基于调制传递函数(MTF)方法,对新型透明黏土材料的光学透明性进行量化分析,并与已有透明土材料的光学透明性进行对比分析,验证其优越性。基于微型十字板剪切试验、压缩固结试验、渗透试验及热传导试验等室内试验方法,对新型透明黏土材料的物理力学特性进行系统研究,探讨其模拟天然黏土的可行性。研究结果表明:新型透明黏土材料的光学透明厚度可达25～40 cm,较目前已有常规透明土材料的光学透明厚度提高约2～3倍;新型材料表现为中低灵敏性黏土、强度随时间明显增加,强度、压缩固结特性与天然淤泥(尤其是海相淤泥)或泥炭土的性质相近,渗透系数为2×10~(-7)～7×10~(-7)cm/s,热传导系数为0.62～0.71 W·M~(-1)·K~(-1)。

Manufacture of new transparent clay and its physical and mechanical properties

The visual model test based on synthetic transparent soil materials and PIV technology is one of the most important geotechnical engineering measurement technologies. However, there are still relatively few transparent materials which can be used for simulating the natural clay. A new transparent material which can simulate the natural clay is developed. It is manufactured by using Carbopol^® Ultrez 10, NaOH powder and distilled water, and nano materials are served as the tracer particles for spackle pattern. The manufacture processes are introduced. Based on the modulation transfer function (MTF) method, the transparency of this material is analyzed, and also compared with that of the previous transparent materials. Based on the laboratory vane tests, consolidation tests, falling head tests and thermal conductivity tests, the geotechnical properties of this synthetic transparent clay are measured. It is shown that the transparent clay presents a good optical transparency within 30~40 cm, which is 2~3 times that of the previous materials. This material is quite consistent with the low or middle-sensitive natural clay, and its strength increases with time obviously. It has similar shear strength and consolidation properties to the natural mud (especially marine mud). Its permeability ranges from 2×10^-7~7×10^-7 cm/s, and its thermal conductivity ranges from 0.62~0.71 W·M^-1·K^-1.