基于TEOS原位交联加固对土遗址水分运移行为影响研究  

The Effect of TEOS in Situ Cross-linking Reinforcement on Moisture Migration Behavior in Earthen Sites

作　　者：汪娟丽[1,2] 李玉虎[1,2] 胡道道[1,2] 

机构地区：[1]陕西师范大学材料科学与工程学院,陕西西安710062 [2]陕西师范大学历史文化遗产保护教育部工程研究中心,陕西西安710062

出　　处：《水利与建筑工程学报》2017年第2期26-31,42,共7页Journal of Water Resources and Architectural Engineering

基　　金：中国博士后科学基金面上资助项目(2013M542322);中国博士后科学基金特别资助项目(2014T70902)

摘　　要：为了研究TEOS原位交联加固对土遗址水分运移行为的影响,采用低场核磁共振技术对TEOS加固重塑土样与未加固重塑土样中水分运移行为与孔隙结构变化规律进行系统研究。通过分析横向弛豫时间T2和孔隙谱峰面积发现:在水分运移过程中,重塑土样内部的水分以束缚水和自由水两种形态存在。吸水过程中,弛豫时间在0.01 ms^1.00 ms区间内的小孔先吸束缚水,而后10 ms^100 ms区间内大孔吸自由水;脱水时先脱大孔中的自由水后脱小孔中的束缚水。随着水分运移循环次数的增加,未加固重塑土样内部孔隙分布发生明显变化,大孔比例减小,小孔比例增大;而加固重塑土样内部孔隙结构保持稳定。这表明TEOS对土遗址土壤团粒起固定化作用,避免了土壤团粒因受水分溶胀、干缩作用而导致自身孔隙结构发生重组。In order to study the effect of TEOS in situ cross - linking reinforcement on moisture transport behavior in earthen sites, the moisture migration behavior and the change of pore structure in unreinforced remolded sample and remolded sample reinforced by TEOS are systematically studied by low field nuclear magnetic resonance technique. By analyzing the transverse relaxation time T2 and the peak area of the pore spectrum, it is found that the water of soil sample is in the form of bound water and free water in the process of moisture migration. During water absorption, bound water is absorbed first by the small pore of which the relaxation time T2 range from 0.01 ms to 1.00 ms and free water is ab- sorbed by large pore which＇s T2 range from 10 ms to 100 ms. On the contrary the free water is dewatering faster than bound water. With the increase of moisture migration cycles, the internal pore structure of the unreinforced remolded sample changed obviously. The proportion of the large pores decreases and the ratio of the small pore increases at the same time. While the internal pore structure of the reinforced remolded sample is stable. It can be concluded that pore structure reforms caused by moisture swelling and shrinkage is prevented in remolded sample reinforced by TEOS.

关 键 词：TEOS 加固材料 水分运移 孔隙结构 土遗址 低场核磁共振 

分 类 号：TU411[建筑科学—岩土工程]