掺纳米层状材料的水泥稳定碎石抗裂性能研究

发布时间：2018-05-08 01:29

本文选题：水泥稳定碎石基层 + 纳米层状材料　；参考：《东南大学》2015年硕士论文

【摘要】：水泥稳定碎石基层具有良好的强度、整体性以及经济效益显著等优点,在我国公路建设中被广泛应用。但随着交通荷载日益增大,水泥稳定碎石基层容易产生收缩裂缝,进而裂缝反射到路面面层,缩短路面的使用寿命。本文针对这一现状,在调研国内外已有研究成果的基础上,主要对掺加纳米层状材料的水泥稳定碎石路用性能和抗裂性能进行了研究。主要研究内容包括：(1)通过对纳米层状材料改良水泥稳定碎石的路用性能研究发现,纳米层状材料掺量为10%,掺煅烧凹凸棒石水泥稳定碎石7d的无侧限抗压强度较空白试验提高12.4%,90d的劈裂强度提高32.4%。纳米层状材料的掺入对水泥稳定碎石的抗压回弹模量和劈裂回弹模量均有一定的影响。掺碱活化凹凸棒石水泥稳定碎石的水稳定性和冰冻稳定性均高于空白水泥稳定碎石。(2)通过对纳米层状材料改良水泥稳定碎石的抗裂性能研究发现,纳米层状材料在10%掺量下,水泥稳定碎石材料的干缩应变与干缩系数最小,养生龄期7d时,和普通水泥稳定碎石相比,碱活化凹凸棒石的最大干缩系数降低了28.1%,原矿凹凸棒石的最大干缩系数降低了22.6%,高岭石的最大干缩系数降低了18.9%。而且干缩应变和干缩系数的数值随着养生龄期的增大和细粒土含量的减小而降低。通过对抗裂性综合评价发现,碱活化凹凸棒石和煅烧凹凸棒石能明显提高水泥稳定碎石的抗裂性能,均高于蒙脱石和高岭石。(3)通过机理试验(SEM、XRD、TG-DSC)研究发现,发现凹凸棒石黏土掺入后生成较多的水化产物,形成网状结构,从而大大减少了水泥稳定碎石的收缩裂缝。(4)根据室内试验结果,选择碱活化凹凸棒石在掺量为水泥质量10%时,对依托工程进行了试验路的铺设,将研究成果应用于工程实际。
[Abstract]:Cement stabilized macadam base has many advantages, such as good strength, integrity and remarkable economic benefit. It is widely used in highway construction in China. However, with the increasing traffic load, the cement stabilized macadam base is easy to produce shrinkage cracks, and then the cracks are reflected to the pavement surface, and the service life of the pavement is shortened. This paper is aimed at this situation. On the basis of the research results at home and abroad, the performance and crack resistance of cement stabilized macadam with nano layered materials are mainly studied. The main contents are as follows: (1) through the study of the road performance of the modified cement stabilized macadam with nano layered materials, the content of the nano layered material is 10%, and the calcined concave is mixed. The unconfined compressive strength of the salient stone cement stabilized macadam 7d is 12.4% higher than that of the blank test. The splitting strength of 90d improves the compressive resilient modulus of the cement stabilized macadam and the split modulus of resilience of the cement stabilized macadam. The water stability and freezing stability of the cement stabilized macadam with alkali activated attapulgite cement It is higher than that of the blank cement stabilized macadam. (2) through the study of the crack resistance of the modified cement stabilized macadam with nano layered material, it is found that the dry shrinkage strain and shrinkage coefficient of the cement stabilized macadam material are the least, the maximum dry shrinkage of the attapulgite is activated by the alkali activated palygorskite compared with the ordinary water sludge stabilized macadam under the 10% dosage of the nano layered material under the addition of the cement stabilized macadam. The coefficient decreased by 28.1%, the maximum dry shrinkage coefficient of the original attapulgite decreased by 22.6%, the maximum dry shrinkage coefficient of kaolinite decreased by 18.9%. and the value of dry shrinkage strain and shrinkage coefficient decreased with the increase of health age and the decrease of the content of fine grained soil. The crack resistance of the cement stabilized macadam can be obviously improved, which is higher than that of the montmorillonite and kaolinite. (3) through the study of the mechanism test (SEM, XRD, TG-DSC), it was found that the attapulgite clay was found to produce more hydrated products and formed a network structure, thus greatly reducing the shrinkage cracks of the cement stabilized macadam. (4) according to the laboratory test results, When alkali activated palygorskite was added to cement quality of 10%, the test road was laid on the support project, and the research results were applied to engineering practice.

【学位授予单位】：东南大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U416.214

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