高强钢纤维碳纳米管混凝土双轴破坏准则及其在千米井筒中的应用

发布时间：2018-09-18 14:15

【摘要】：随着社会经济、科技水平的快速发展和混凝土使用环境日趋恶劣,研究高强高性能混凝土已成为目前以及未来相当长时期内建筑材料科学与技术发展的一个主要方向。因此,本文根据基金项目进行了高强钢纤维碳纳米管混凝土的相关研究。根据钢纤维强度高、韧性好,而碳纳米管所具有的强度高、密度小、韧性大等优点,首先分别确定了强度等级为C70-C100的素混凝土及高强钢纤维碳纳米管混凝土的最优配合比;然后又分别对其强度、耐久性、收缩徐变、单轴受压和双轴受压等进行了试验研究;结果证明了高强钢纤维碳纳米管混凝土具有强度高、耐久性好、韧性大、延性好等诸多优良特性。具体研究内容如下:(1)通过探索试验,首先确定了高强混凝土(High Strength Plain Concrete,简称为HSPC),配合比范围,并在此基础上进行了正交试验,最后得到了高强混凝土最优配合比;再通过单掺、混掺钢纤维及碳纳米管,最终得到了高强钢纤维碳纳米管混凝土(High Strength Steel Fiber and Carbon Nanotubes Reinforced Concrete,简称为HSSFCNRC)最优配合比;(2)将HSPC与未掺矿物掺合料的普通高强混凝土(High-Strength Concrete without Mineral Admixtures,简称为HSCwMA)、HSPC与HSSFCNRC在力学性能、耐久性进行了对比分析。结果表明,HSSFCNRC具有较高的强度及较好的耐久性;(3)研究了HSPC在实验室内环境条件下的收缩徐变特性,并分别比较了CEB-FIP(1990)模型、B3模型、GL2000模型对本试验结果的适应性。结果表明,B3模型与试验值最为接近。然后,又对水胶比、矿物掺合料、湿度、温度等方面进行了综合修正,从而使得修正后的B3模型更为准确;(4)对HSPC、HSSFCNRC分别进行了单轴受压试验,并建立了相应的本构关系;(5)对HSPC、HSSFCNRC也分别进行了双轴受压试验,并建立了双轴受压破坏准则及其本构关系;(6)根据平煤一矿回风井相关资料,以及本文所建立的混凝土双轴破坏准则及本构关系,建立了井筒平面应变模型,并利用ANSYS软件进行了仿真模拟,对井壁在其自重、围岩压力、孔隙水压力综合作用下的破坏形式进行了模拟分析。
[Abstract]:With the rapid development of social economy, the rapid development of science and technology and the worse environment for concrete use, the study of high strength and high performance concrete has become a main direction of the development of building materials science and technology at present and in a long period of time in the future. Therefore, according to the fund project, the relevant research of high strength steel fiber carbon nanotube concrete is carried out in this paper. According to the advantages of high strength and good toughness of steel fiber, and high strength, low density and high toughness of carbon nanotubes, the optimum mix ratio of plain concrete with strength grade C70-C100 and high strength steel fiber carbon nanotube concrete is determined respectively. Then, the strength, durability, shrinkage and creep, uniaxial compression and biaxial compression of high strength steel fiber carbon nanotube concrete are studied respectively, and the results show that high strength steel fiber carbon nanotube concrete has high strength, good durability and high toughness. Good ductility and many other excellent characteristics. The specific research contents are as follows: (1) through the exploration test, the range of (High Strength Plain Concrete, mixture ratio of high strength concrete is determined firstly, and on the basis of this, the orthogonal test is carried out, finally the optimum mix ratio of high strength concrete is obtained, and then the optimum mix ratio of high strength concrete is obtained by single mixing. Mixed steel fibers and carbon nanotubes, Finally, the optimum mix ratio of high strength steel fiber carbon nanotube concrete (High Strength Steel Fiber and Carbon Nanotubes Reinforced Concrete,) is obtained. (2) the mechanical properties of HSPC and ordinary high strength concrete (HSCwMA) without mineral admixture are obtained. The durability is compared and analyzed. The results show that HSSFCNRC has higher strength and better durability. (3) the shrinkage and creep characteristics of HSPC in laboratory environment are studied, and the adaptability of CEB-FIP (1990) model / B3 model GL2000 to the test results is compared. The results show that the B3 model is most close to the experimental value. Then, the water / binder ratio, mineral admixture, humidity, temperature and so on are comprehensively revised, which makes the modified B3 model more accurate. (4) uniaxial compression test of HSPC,HSSFCNRC is carried out. The corresponding constitutive relation is established. (5) the biaxial compression test of HSPC,HSSFCNRC is also carried out, and the biaxial compression failure criterion and its constitutive relation are established. (6) according to the relevant data of the return air shaft in the first coal mine, As well as the concrete biaxial failure criterion and constitutive relation established in this paper, the plane strain model of wellbore is established, and the simulation is carried out by using ANSYS software. The failure modes under the combined action of pore water pressure were simulated and analyzed.
【学位授予单位】：河南理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TU528

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