纳米矿粉水泥土固化机理及损伤特性研究
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摘要
水泥土工程应用广泛,然而工程实践表明,水泥土强度不够高、形成的复合地基后期变形较大等问题制约了水泥土的进一步应用,选择适宜的外掺剂改善水泥土性能是解决这些问题的重要途径。随着纳米科技的发展以及纳米材料在混凝土等水泥基材料中的应用研究,在水泥土中掺加性能优异的纳米级材料将成为一种新的尝试。本文在纳米矿粉水泥土力学特性试验研究的基础上,探讨了纳米矿粉水泥土固化机理,为纳米材料进一步应用于水泥土提供微观层次上的依据。
     在总结纳米材料在水泥基材料中的应用现状以及应用前景的基础上,本文首先分析了三种纳米矿粉的微结构特性及其与普通矿粉的微结构特性异同;通过水泥土室内无侧限抗压强度试验,探讨了纳米矿粉掺入比和龄期对水泥土强度的影响规律。试验结果表明,适宜的纳米硅粉掺入比下,各个龄期的水泥土强度显著提高;纳米铝粉对水泥土的增强效果不明显;直至90d时,纳米钛粉仍然降低水泥土强度。根据试验结果,分析了纳米硅粉水泥土的变形特性,并对其应力应变曲线进行了二次抛物线拟合分析,推导了曲线上升段的表达式。
     结合水泥石强度试验和XRD试验,从火山灰效应、填充效应、水泥水化促进作用和微结构改善作用等方面探讨了三种纳米矿粉在水泥水化硬化过程中的作用机理;从这四个方面出发,对比分析了纳米硅粉和普通硅粉作用机理的异同点,分析表明,纳米硅粉的优异特性主要表现为颗粒细度、晶体结构、表面羟基等特性。
     设计了三组室内试验,分别探讨了纳米硅粉对粘性土物理力学性能的影响;结合试验结果和土质学基本理论,提出从水分子吸附作用、胶结作用、填充作用三个方面探讨纳米硅粉与粘性土之间的作用机理。
     结合SEM试验,探讨了纳米硅粉水泥土的微结构特点。在研究水泥浆—纳米硅粉、纳米硅粉—粘性土、水泥浆—粘性土相互作用的基础上,将纳米硅粉水泥土的固化机理总结为:水泥水化物的胶结作用、粘土颗粒中的离子交换效应和“二次反应”、纳米硅粉的火山灰效应、纳米硅粉的填充效应、纳米硅粉的胶结作用。根据固化机理,解释了水泥土和水泥石强度试验中的一些现象和规律,分析了纳米硅粉改性水泥土的适用性。
     最后,通过室内试验分析了纳米硅粉水泥土的细观损伤机制及其损伤特性,建立了无侧限轴向压缩条件下的弹塑性损伤模型,分析了损伤演化规律。研究表明,纳米硅粉水泥土内部存在明显的损伤现象,掺加纳米硅粉,水泥土损伤特性发生改变:与试验曲线的对比结果表明,本文采用的损伤变量和损伤模型能够较真实地反映纳米硅粉水泥土的损伤特性。
Cemented soil has been extensively used to ground treatment, however, engineering experiences suggest that low strength and large deformation has restricted its further application in the engineering. To improve engineering properties, many additives have been added to cemented soil. With the progress of nanometer technology, nanometer materials have been applied to modify cement-based materials, so it is a trail to introduce nanometer material with particular characteristics to cemented soil as a new kind of additive. In the paper, three kinds of nanometer materials are used for the cemented soil. Based on laboratory tests and theoretical analysis, the paper discussed reinforcement mechanism of the cemented soils stabilized the nanometer materials, which will provide research foundation for further application of the nanometer materials in cemented soil.
    Based on analysis on research existing status and application foreground of nanometer materials in cemented based material, the paper firstly discusses the microstructure properties of the three nanometer materials and compares them with the corresponding ordinary crystals. By unconfining compression strength tests of the cemented soil stabilized with the nanometer materials, influencing rules of nanometer material addition ratio and curing period on the strength are individually analyzed. The results suggest that nanometer silica fume (nanometer SiOx) can greatly improve the strength of cemented soil at various curing period, nanometer aluminium fume (nanometer AljOs) can not improve the strength, and nanometer titanium fume (nanometer TiO2) still reduce the strength until curing period of 90d. According to testing results, the stress-strain curve of the cemented soil stabilized the nanometer silica fume is fitted using a quadratic parabolic curve and expression equation for upward sector of the stress-stra
    in curve is given.
    Through strength tests and XRD tests for cemented stone, the paper presents action mechanism of the nanometer materials in the cement hydration and hardening process: pozzolanic effect, filling effect, acceleration action for the cement hydration, and improving action for microstructure. From the four aspects, the modified mechanism of the nanometer silica fume and ordinary silica fume in cement paste are compared. The analysis results show that the particular properties of the nanometer silica fume include particle fineness, crystal structure and surface hydroxy, etc.
    A serial of laboratory tests are performed to study physical and mechanic properties of the clay with the addition of the nanometer silica fume. Based on testing results and soil theory, the modified mechanism of the nanometer silica fume in the clay is proposed: water molecule adsorption action, cementation action and filling action.
    
    
    Combining the SEM tests, the microstructure features of the cemented soil of nanometer silica fume are concluded. On the basis of analysis on the pairwise action of cement paste, nanometer silica fume and clay, the paper proposes the reinforcement mechanism of the cemented soil stabilized with nanometer silica fume. The reinforcement mechanism includes cementation action of cement hydrate, ionic exchange and quadrate reaction of clay particle, pozzolanic effect, filling effect and cementation action of nanometer silica fume. According to the reinforcement mechanism, some experimental phenomena and rules in the strength tests of cemented soil and cemented stone are explained. The paper also discusses the applicability of the nanometer silica fume in the cemented soil as an additive.
    Based on the analysis of micro-damage mechanism and damage performance of the cemented soil stabilized with nanometer silica fume, an elasto-plasticity damage model under uniaxial compression condition is established. Damage evolution laws are analyzed by the load-unload tests. Analysis results show that obvious damage occurs in the inner of the cemented soil stabilized with nanometer silica fume and the added nanometer silica fume can improve the damage
引文
Andrew J. Allen and Richard A. Livingston. Relationship between difference in silica fume additive and fine-scale microstructural evolution in cement based material. Advn Cem Bas Mat. 1998, (8): 118-131
    Asaga. K, Kuga.H, Takahashi S, et. at. Effects of pozzolanic additives in the Portland cement on the hydration rate of alite. Proceeding of the 10th international congress on the chemistry of cement. 1997, 3ⅱ107
    Brunauer, E.E., R. T. Hemmings, M-H Zhang, B. J. Cornelius, and D. M. Golden. Hydration in high-volume fly ash concrete binders. ACI Materials J. 1994, 91(2): 382-389
    C. Plowman and J. G. Cabrera. The influence of pulverized fuel ash on the hydration reactions of calcium aluminate. In: effects of fly ash incorporation in cement and concrete(S. Diamond Ed.). Proceedings, symposium N Annual Meetings. 1981, 71-81
    De Larrard F, Sedran T. Optimation of ultra-high performance concrete by the use of a packing model. Cem. Coner. Res. 1994, 24 (6): 685-695
    D.R.G. Mitchell, I. Hinczak and R.A.D. Interaction of silica fume with calcium hydroxide solutions and hydrated cement pastes. Cem. Concr. Res. 1998, 28(11): 1571-1584
    Gens, A. and Nova, R. Conceptual bases for a constitutive model for bonded soils and weak rocks. Proc. 1st. Int. Conf. Hard soils and soft Rocks. 1993, 485-494
    Gopalan M. K. Nucleation and pozzolanic factors in strength development of class F fly ash concrete. ACI Materials J. 1993, 90(2): 117-121
    Halse Y, Pratt P L, Dalziei J A, et, at. Development of microstrueture and other properties in fly ash OPC systems. 1984, 14(4): 491-484
    H. F.W. Taylor. Cement chemistry. London: Thomas Telford Publishing, 1997, 275
    H. N. Stein and J. M. Stevels. Influence of silica on the hydration of 2CaO·SiO_2. J. Appl. Chem. 1964, 14: 338-336
    I. Jawed and J. Skalny. Hydration of tricalcium silicate in the presence of fly ash. In: effects of fly ash incorporation in cement and concrete(S. Diamond Ed.). Proceedings, symposium N Annual Meetings. 1981, 60-70
    J.A. Larbi, A. L. Fraay, J.M. Bijen. The chemistry of the pore fluid of silica fume-blended cement systems. Cem. Concr. Res. 1990, 20(2): 506-516
    J. T. Huang and D. W. Airey. Properties of artificially cemented carbonate sand. J. Geotech. Engrg., ASCE. 1998, 124(6): 492-499
    Kiyono Kasama, Hidetoshi Ochina, and Noriyuki Yasufuku. On the sress-strain behavior of lightly cemtend clay based on an extended critical state concept. Soils and Foundations. 2001, 40(5): 37-47
    
    
    K. Mohan and H. F. H Taylor. Pastes of tricaicium silicate with fly ash-annalytical electron microscopy, trimethysilylation and other studies. In: effects of fly ash incorporation in cement and concrete (S. Diamond Ed.). Proceedings, symposium N Annual Meetings. 1981, 54-59
    K. Ogawa, H. Uchikawa, I. Yasui. The mechanism of the hydration in the system-pozzolana, Cem. Concr. Res. 1980, 10(3): 683-696
    Kondo, D. Der Einbau yon TiO_2 in die Pkasen des Portlandzementklinkers. Zement-Kalk-Gips. 1979, 32-35
    Konfel, R. Miscibilities of special elements in tricalcium silicate and alite and the hydration properties of C_3S solid solution. 5th Int. Symp. Chem. Cement, Tokyo PI. 1968, 262-266
    Lange F, Mortel H, Rudent V. Dense packing of cement pastes and resulting consequences on mortal properties. Cem. Concr. Res. 1997, 27(6): 997-1009
    Leroueil, S. and Vaughan, P. R. The general and congruent effects of structure in natural soils and soft rocks. Geotechnique. 1990, 40(3): 467-488
    Liu, M. D., Carter, J. P. and Airey, D. W. An elastoplastic stress-strain model for cemented carbonate soils. Proc. 14th. Int. Conf. On SMFE. 1997, (1): 367-372
    Maria Georgescu and Alina Badanoiu. Hydration process in 3CaO. SiO_2-silica fume mixtures. Cem. & Con. Com. 1997, 19: 295-300
    Marusin S L, Shotwell L B. Alkali-silica reaction in concrete caused by densified silica fume lumps: A case study. Cement, concrete, Aggregate, CCAGDP. 2000, 22(2): 90-94
    Mehta P K Influence of fly ash characteristics on strength of Portland-fly ash cement. Cem. Concr. Res. 1985, 15(4): 669-674
    Mitchell D R G, Hinczak I, Day R A. Interaction of silica fume with calcium hydroxide solutions hang hydrated cement paste. Cem. Concr. Res. 1998, 28(11): 1571-1584
    M. R. Coop., J. H. Atkinson. The mechanics of cemented carbonated sands. Geotechnique, 1993, 43(1): 53-67
    P. L Raymen. The effect of pulverized fuel ash on the C/S molar ratio and alkali content of calcium silicate hydrations in cement. Cem. Concr. Res. 1982, 12(1): 133-140
    S. Li, D.M. Roy and A. Kumar. Quantitative determination of pozzolanas in hydrated systems of cement or Ca(OH)_2 with fly ash or silica fume. Cem. Concr. Res. 1985, 15(6): 1079-1086
    S. Uchiwaka and S. Uchida. Influence of pozzolana on the hydration of CA. In: 7th international congress on the chemistry of cement. 1980, (Ⅲ, Ⅳ): 24-29
    M. E. Tadors, J. Skalny et R. S. Kalyoncu. Early hydration of C_3S. J. Am. Ceram. Soc. 1976, 59(2): 344-348
    V. Kasselouri, N. Kouloumbi and Th. Thomopouios. Performance of silica fume—calcium hydroxide mixtures as a repair material. Cem. & Con. Com. 2001, 23(1): 103-110
    
    
    Wei F, Grutzeck. M. W., Roy. D. M. The retarding effects of fly ash upon the hydration of cement paste: the first 24 hours. Cem. Concr. Res. 1985, 15(1): 174-184
    Xiaozhong Zhang, et al. Nanostructure of Calcium slicate hydrate gels in cement pastes. J. Am. Ceram. Soc. 2000, 83(10): 2600-2604
    Ya Mei Zhang, Wei Sun and Han Dong Yan. Hydration of high-volume fly ash cement pastes. Cem. & Con. Com. 2000, 22(6): 445-452
    Yu. Y., Pu, J. and Ugai, K. A damage model for soil-cement mixture. Soils and Foundations. 1998, 38(3): 1-12
    James K.Michell.岩土工程土性分析原理.高田瑞等译.南京:南京工学院出版社,1988
    J.Skalny,J.F Young.波特兰水泥的水化机理.第七届国际水泥化学会议论文集.北京:中国建筑工业出版社,1985,169-214
    R.Bucchi.原料的性质和制备对生料反应性能的影响.第七届国际水泥化学会议论文集.北京:中国建筑工业出版社,1985,3-46
    Tenoutasse N,Redco S A.混合材料水泥的耐久性与其微结构间的关系.第八届国际水泥化学论文集(中译本,下册).北京:中国建材科学研究院,1987,63-69
    Wayne s.,许贤敏.水泥土——一种用途广泛的材料.国外建筑科学,1994,23(4):58-61
    白冰,周健.扫描电子显微镜测试技术在岩土工程中的应用与进展.电子显微学报,2001,20(2):154-160
    蔡希高.氢键在水泥水化中的作用.广西土木建筑,1996,21(4):171-177
    陈大明.纳米陶瓷复合材料进展.材料工程,1996,(6):8-12
    陈更生,彭建中,韩静云等.水泥土强度的试件形状和尺寸效应试验研究.岩土工程学报,2002,24(5):580-583
    陈国兴等.土质学与土力学.北京:水利水电出版社,2002
    陈荣升.超细矿粉和聚合物改性的水泥基高性能材料研究[硕士学位论文].杭州:浙江工业大学,2002
    陈拴发,周维科.掺矿粉水泥的水化机理研究.西安建筑科技大学学报,2000,32(2):166-169
    邓宗才,钱在兹.钢纤维混凝土的弹塑性损伤模型.力学与实践,2000,22(4):34-37
    地基处理手册(第二版)编写委员会.地基处理手册(第二版).北京:中国建筑工业出版社,2000
    董邑宁.水泥土强度及渗透特性试验研究.青海大学学报(自然科学版),2000,18(6):13-16
    恩·S·亚当斯克.水泥土——一种用途广泛的材料.东北水利水电,1992,(5):45-49
    冯金良,赵泽三,高田瑞.无定形游离氧化铁脱水老化对粘性土物理性质的影响.工程地质学报,1993,1(2):85-92
    
    
    封伯吴,张立翔,李桂青.混凝土损伤研究综述.昆明理工大学学报,2001,26(3):21-30
    高国瑞,李俊才.水泥加固(改良)软土地基的研究.工程地质学报,1996,4(1):45-62
    高俊良,赵健.水泥土后期强度利用分析.煤田地质与勘探,2003,31(1):47-48
    宫必宁,李淞泉.软土地基水泥深层搅拌加固土物理力学特性研究.河海大学学报,2000,28(2):101-105
    龚晓南.地基处理新技术.西安:陕西科学技术出版社,1997
    郝巨涛.水泥土材料力学特性的探讨.岩土工程学报,1991,13(3):53-59
    何明,符晓陵,徐道远.混凝土的损伤模型.福州大学学报,1994,22(4):109-114
    何思明.双标量描述土的损伤模型及其应用.岩土力学,2002,23(3):337-340
    黄殿英,张可能,曾祥熹.SF对水泥土的影响初探.大地构造与成矿学,1995,19(3):284-287
    黄鹤,张俐,扬晓强等.水泥土材料力学性能的试验研究.太原理工大学学报,2000,31(6):705-709
    黄新,胡同安.水泥—废石石膏加固软土的试验研究.岩土工程学报,1998,20(5):72-74
    黄新,杨晓刚,胡同安.硫酸盐介质对水泥加固土强度的影响,工业建筑,1994(9):19-23
    黄新,周国钧.水泥加固土硬化机理初探.岩土工程学报,1997,19(1):62-66
    季韬,黄与舟,郑作樵.纳米混凝土物理力学性能研究初探.混凝土,2003,161(3):13-14
    蒋林华,令宝玉,蔡跃波.高掺量粉煤灰水泥凝胶材料的水化性能研究.硅酸盐学报,1998,26(6):695-701
    孔令伟,罗鸿禧,袁建新.红粘土有效胶结特征的初步研究.岩土工程学报,1995,17(5):43-47
    孔令伟,罗鸿禧.游离氧化铁形态转化对红粘土工程性质影响.岩土力学,1993,14(4):25-39
    李刚.纳米材料水泥土工程性状试验研究[硕士学位论文].杭州:浙江大学,2003
    李俊才,赵泽三,高国瑞.水泥土的微结构特征及分析.成都理工学院学报,2000,27(4):388-393
    李俊才,周显祥,梁永谨.软土含水量对粉喷法加固效果的影响.成都理工学院学报,1998,25(3):417-421
    李文斌.从水泥土强度增长机理分析看增强措施.甘肃水利水电技术,1994(2):63-71
    李新宇,方坤和.硅粉对水泥硬化浆体微结构影响的研究进展.硅酸盐学报,2003,(1):54-57
    梁仁旺,张明,白晓红.水泥土的力学性能试验研究.岩土力学,2001,22(2):211-213
    刘焕存.夯实水泥土强度特性试验研究.岩土工程技术,1996,(3):16-25
    刘焕存.夯实水泥土变形特性试验研究.岩土工程技术,1997,(1):19-27
    牟善彬.粉煤灰的微观形态及其在水泥中的水化.新世纪水泥导报,2002,(2):31-33
    
    
    牛全林,冯乃谦,杨静.矿渣超细粉作用机理的探讨.建筑材料学报,2002,5(1):84-89
    蒲心诚,王勇威.高效活性矿物掺料与混凝土的高性能化.混凝土,2002,148(2):3-6
    余希林,宋国君,江峰等.聚合物/粘土纳米复合材料研究进展.青岛大学学报,2002,17(2):46-49
    沈卫国,周明凯,赵青林.湿塑性水泥土的研究.新世纪水泥导报,2001,(1):23-25
    沈珠江.结构性粘土的弹塑性损伤模型.岩土工程学报.1993,(3):21-28
    沈珠江,章为民.损伤力学在土力学中的应用.第一届全国计算岩土力学研讨会论文集,1987
    孙安江.粉煤灰硅灰和高强混凝土.房材与应用,1997(5):43-45
    孙红,赵锡宏.结构性软土的损伤及其对地基沉降的影响.岩土力学,1999,20(1):19-21
    孙红,赵锡宏.软土的各向异性弹塑性损伤分析.岩土力学,1999,20(3):7-12
    孙红,赵锡宏,崔飞.横观各向同性土的弹性非线性损伤分析.同济大学学报,1999,20(4):443-447
    孙尧,周刚.纳米陶瓷及其应用前景.化工新型材料,2001,29(7):6-8
    谭罗荣,孔令伟.某类红粘土的基本特性与微观结构模型.岩土工程学报,2001,23(4):458-462
    汤怡新,刘汉龙,朱伟.水泥固化土工程特性试验研究.岩土工程学报,2000,22(5):549-554
    田文玉.硅粉的研究及应用现状.重庆交通学院学报,1998,17(2):100-107
    童小东,水泥土添加剂及其损伤模型试验研究[博士学位论文].杭州:浙江大学.1998.
    中华人民共和国国家标准.土工试验方法标准(GB/T 50123-1999),1999
    王爱勤,张承志,唐明述.火山灰质材料的填充作用,1995(5):19-21
    王冲,蒲心诚,刘芳等.纳米颗粒材料在水泥基材料中应用的可行性研究.建筑石膏与胶凝材料,2003,(2):22-23
    王娟娣.水泥搅拌法加固宁波地区含有有机质土的试验研究[硕士学位论文].杭州:浙江大学,2000
    王立峰.纳米硅水泥土工程特性及本构模型研究[博士学位论文].杭州:浙江大学,2003
    王立峰,朱向荣,丁同福.纳米硅水泥土工程特性的试验研究.岩土工程技术,2003,23(4):187-192
    王文军,朱向荣.纳米硅粉水泥土的工程特性及固化机理初探.地质与勘探,2003,39(增刊):101-104
    王星华,粘土固化浆液固结过程的SEM研究.岩土工程学报,1999,21(1):34-40
    王银梅.粉煤灰水泥与粘土间相互作用机理探讨.房材与应用,2000,28(2):47-48
    吴宝琨,卢璋,莲慧珍.建筑材料化学.北京:中国建筑工业出版社,1984
    吴波,袁杰.杨成山.高温后高强混凝土的微观结构分析.哈尔滨建筑科技大学学报,1999,
    
    32(3):8-12
    夏旺民,郭增玉.Q_1黄土的弹塑性损伤本构模型.第九届土力学及岩土工程学术会议论文集(上册).北京:清华大学出版社,2003,248-253
    熊国宣,邓敏,宋碧涛等.纳米材料在混凝土中应用的思考.混凝土与水泥制品,2002,(5):18-21
    熊厚金,林天健,李宁.岩土工程化学.北京:科学出版社,2001
    荀勇.有机质含量对水泥土强度的影响与对策.四川建筑科学研究,2000,26(3):58-60
    徐翠云.我国纳米科技研究应用现状及发展趋势分析.江苏环境科技,2002,15(3):46-48
    许惠德,马金荣,姜振泉.土质学及土力学.徐州:中国矿业大学出版社,1995
    杨坪,彭振斌.硅粉在混凝土中的应用探讨.混凝土,2002,147(1):11-13
    杨晓华,俞永华,顾安全.水泥黄土损伤力学模型探讨.第九届土力学及岩土工程学术会议论文集(上册).北京:清华大学出版社,2003,365-368
    叶青.纳米复合水泥结构材料的研究与开发.建筑石膏与胶凝材料,2001:4-6
    叶青.纳米SiO_2与硅粉的火山灰活性的比较.混凝土,2001,137(3):19-21
    殷有泉.岩石的塑性损伤及其本构表述.地质科学,1995,30(1):63-70
    张光玉,杨德文.粉煤灰及其高强度混凝土的微观机理.铁道科学物资管理,1992,10(5):25-25
    张立德,牟季美.纳米材料和纳米结构.北京:科学出版社,2001
    张土乔.水泥土的应力应变关系及搅拌桩破坏特性研究[博士学位论文].杭州:浙江大学,1992
    张文生,陈益民等.粉煤灰与水泥熟料共同水化硬化的基础研究进展及评述.硅酸盐学报,2000,28(2):160-164
    赵伟安,李东样,侯万国.聚合物/粘土纳米复合材料的研究进展.胶体与聚合物,2002,20(3):32-37
    赵锡宏,孙红,罗冠威.损伤土力学.上海:同济大学出版社,2000
    周承刚,高俊良.水泥土强度的影响因素.煤田地质与勘探,2001,29(1):45-48
    周承刚,高俊良,李曦滨.粉煤灰在搅拌地基处理时对水泥土强度的影响.河北建筑科技学院学报,2001,18(1):78-80
    周国均,胡同安,沙炳春等.深层搅拌法加固软粘土技术.岩土工程学报,1981,3(4):54-62
    左美祥,黄志杰,张玉敏.纳米SiO_x在涂料中的分散及改性作用.现代涂料与涂装,2001,(3):1-2
    朱卫华,印友法,蒋林华.硅粉水泥石小角度X射线散射实验研究(Ⅰ)—微孔各向异性.建筑材料学报,2001,4(2):116-121
    朱向荣,王文军.纳米硅粉水泥固化土的试验研究.水利水电技术,2004,3S(1):87-90

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