纳米CaO水泥土的工程特性研究

发布时间：2018-05-13 19:12

  本文选题：水泥土 + 纳米CaO　； 参考：《吉林大学》2015年硕士论文

【摘要】：水泥土由于其所具有的施工方便、对周围环境影响较小、价格低廉和加固效果显著等特点被广泛应用于各类软土加固工程中。水泥土是一种人工改良软土的材料，将需要处理的软土经过与水泥搅拌而形成的水泥土具有整体性、低压缩性、水稳定性。但后期经过验证发现水泥土由于强度不高、变形较大在很多应用上也会受到限制。 论文根据纳米材料所具有的优异性能，将纳米CaO掺入到水泥土中，通过正交设计试验和全面试验，分析纳米CaO水泥土在不同水泥掺入比与不同纳米CaO掺入比的条件下，水泥土的无侧限抗压强度变化规律；将纳米CaO水泥土进行不同养护龄期后通过声波测速试验观察其波速的变化情况而比较水泥土的强度改变；分析了纳米CaO水泥土的应力-应变关系特征和强度增长规律，并采用了纯水泥土与纳米CaO水泥土的电镜照片，分析了的微观结构特征和结构的变化。研究认为： （1）在正交设计试验中发现水泥掺量为20%，纳米CaO掺入比为10‰，水灰比0.35时水泥土的无侧限抗压强度最高，这个组合为正交设计中的最佳配比。 （2）通过全面试验中在四个水泥掺入比中当纳米CaO含量为10‰时在同一养护龄期时无侧限抗压强度最高，也验证了正交试验设计结果的可靠性。 （3）通过扫描电镜能够看到水泥土与纳米CaO水泥土相对原状土大孔隙减小，结构更加密实；纳米CaO作为水泥土外掺剂在水泥土中将土团粒能够相对更加紧密胶结的同时，也细化了孔隙。 （4）掺加纳米CaO的水泥土的应力-应变关系上升段时似弹性变形阶段的曲线斜率要与同养护龄期同水泥掺入比的斜率大。 （5）经过拟合得到水泥土变形模量与抗压强度关系式为：E50=64qu，，纳米CaO水泥土变形模量与抗压强度关系式为：E50=73qu。
[Abstract]:Cement soil is widely used in all kinds of soft soil reinforcement projects because of its convenient construction, small impact on the surrounding environment, low price and remarkable reinforcement effect. Cement soil is a kind of artificial improved soft soil material. The cement soil which needs to be treated by mixing with cement has the characteristics of integrity, low compressibility and water stability. But after later verification, it is found that the large deformation of cement soil is limited in many applications because of its low strength. According to the excellent properties of nanomaterials, nanometer CaO was mixed into cement soil. Through orthogonal design and comprehensive test, the paper analyzed the conditions of different cement blending ratio and different nano-CaO blending ratio of nano-CaO cement soil. The change rule of unconfined compressive strength of cement-soil is obtained, and the change of cement-soil strength is compared by sonic velocimetry test after different curing age of CaO cement soil. The stress-strain relationship and strength growth of nanometer CaO cement soil were analyzed, and the microstructure characteristics and structural changes of pure cement soil and nano-CaO cement soil were analyzed by electron microscope. The study found that: 1) in the orthogonal design experiment, it is found that the cement content is 20, the ratio of nanometer CaO is 10 鈥

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