Low field proton nuclear magnetic resonance(NMR) technology is used to measure the distribution of transverse relaxation time T2 of solidified dredging silt soil to study the content and distribution law of pore water in solidified soil. Results show that there is only one main peak in the distribution of relaxation time of solidified soil samples of different cement dosages; the peak area decreases gradually with the growth of curing age and the increase of cement dosage. Pore water content decreases gradually, and the decrease first starts from big pores. The main effect of curing age is reducing the moisture content in the big pores, whereas cement is not only beneficial for reducing the moisture content in the big pores, but also the moisture in the small pores. With the growth of curing age and the increase of cement dosage, the scope of T2 distribution of solidified soil narrows and the distribution tends to short relaxation time, and pore water is distributed in smaller pores gradually. The weighted average relaxation time T2 declines rapidly with the growth of curing age first, and the decline rate decreases gradually after 7 days. Solidified soil’s total nuclear magnetic signal amplitude of T2 shows an overall trend of decrease with the curing age growth, and the speed slows down after 7 days; this is because the water is consumed or converted into mineral water due to internal chemical reaction in solidified soil. Nuclear magnetic resonance(NMR) technology can well present the content and distribution law of pore water in the process of solidification.
Key words
dredging silt /
solidified soil /
nuclear magnetic resonance /
T2 distribution /
pore water /
relaxation time
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References
[1] 林 莉,李青云,吴 敏.河湖疏浚底泥无害化处理和资源化利用研究进展[J].长江科学院院报,2014,31(10):80-88.
[2] 程福周,雷学文,孟庆山,等.水泥-水玻璃固化东湖淤泥的室内试验研究[J].人民长江,2013,44(24):45-48.
[3] 杨云芳,陈 萍,施萍萍.化学固化对淤泥颗粒粒径及含水率影响的试验研究[J].浙江理工大学学报,2008,25(1):38-40,69.
[4] 张春雷.基于水分转化模型的淤泥固化机理研究[D].南京:河海大学,2007.
[5] 田慧会.多相土中水分迁移与相变过程的核磁共振探测方法研究[D].北京:中国科学院大学,2014.
[6] 赵 杰,姜亦忠,王伟男,等.用核磁共振技术确定岩石孔隙结构的实验研究[J].测井技术,2003,27(3):185-188.
[7] 李杰林. 基于核磁共振技术的寒区岩石冻融损伤机理试验研究[D].长沙:中南大学,2012.
[8] 王 萍,屈 展.基于核磁共振的脆硬性泥页岩水化损伤演化研究[J].岩土力学,2015,36(3):687-693.
[9] 郑贵强,凌标灿,郑德庆,等.核磁共振实验技术在煤孔径分析中的应用[J].华北科技学院学报,2014,11(4):1-7.
[10]李添宝,吴 越,罗 敬.利用核磁共振法定量分析植物油中多种脂肪酸及水含量[J].食品科学,2014,35(16):212-216.
[11]要世瑾,杜光源,牟红梅,等.基于核磁共振技术检测小麦植株水分分布和变化规律[J].农业工程学报,2014,30(24):177-186.
[12]姚 武,佘安明,杨培强.水泥浆体中可蒸发水的1H核磁共振弛豫特征及状态演变[J].硅酸盐学报,2009,37(10):1602-1606.
[13]佘安明,姚 武.质子核磁共振技术研究水泥早期水化过程[J].建筑材料学报,2010,13(3):376-379.
[14]AZMATCH T F, SEGO D C, ARENSON L U, et al. Using Soil Freezing Characteristic Curve to Estimate the Hydraulic Conductivity Function of Partially Frozen Soils[J]. Cold Regions Science and Technology 2012, 83/84: 103-109.
[15]谭 龙,韦昌富,田慧会,等.冻土未冻水含量的低场核磁共振试验研究[J].岩土力学,2015,36(6):1566-1572.
[16]COATES G R, XIAO L L, PRAMMER M G. NMR Logging Principles and Application[M]. Houston: Halliburton Energy Services Publication, 1999.