玄武岩纤维水泥稳定碎石路用性能试验研究

发布时间：2018-06-26 01:22

本文选题：半刚性基层 + 水泥稳定碎石　；参考：《中国海洋大学》2014年硕士论文

【摘要】：水泥稳定碎石类半刚性基层综合性能较好已经成为现在高等级公路的主要应用形式，但是它同样存在一些不足，本文针对其面临抗收缩性不好等诸多问题，通过改善材料本身性能，即在水泥稳定碎石中掺加玄武岩纤维，在强度得到保证的前提下来有效改善半刚性基层路用性能。通过大量试验，对玄武岩纤维水泥稳定碎石的基本力学性能、收缩性能以及抗冻性能进行系统的研究，主要内容包括：（1）通过均匀试验进行玄武岩纤维水泥稳定碎石配合比设计，首先根据三个影响因素（水泥剂量、纤维长度、纤维剂量）拟定五组配合比，然后以7d无侧限抗压强度、7d劈裂抗拉强度和7d干缩系数为评价指标进行试验。试验包括五组配合比的击实试验（确定最优含水量和最大干密度）、试件制作以及三个评价指标系列试验。最后由线性分析得到三个评价指标的回归模型，结合相关规范与工程实际，得出三个影响因素之间的最优组合——玄武岩纤维水泥稳定碎石性能最优配合比。（2）针对玄武岩纤维水泥稳定碎石性能最优配合比与无纤维普通水泥稳定碎石配合比这两组配合比进行基本力学性能试验研究，包括抗压强度及劈裂抗拉强度试验。分别采用不同养护龄期来研究两组配合比下抗压强度及劈裂抗拉强度的变化规律，同时通过对比来分析玄武岩纤维对水泥稳定碎石的影响。结果表明，玄武岩纤维的掺入使水泥稳定碎石的两种强度均得到一定的提高。（3）分别采用干缩试验及温缩试验的方法研究玄武岩纤维水泥稳定碎石性能最优配合比与无纤维普通水泥稳定碎石配合比两组配合比下的抗收缩性能。采用不同养护龄期进行系列试验。结果表明，玄武岩纤维的掺入可降低水泥稳定碎石的干缩系数和温缩系数，提高水泥稳定碎石的抗收缩性。（4）以养护龄期为28d冻融循环为5次的冻融试验方法，研究玄武岩纤维水泥稳定碎石性能最优配合比与无纤维普通水泥稳定碎石配合比两组配合比下的抗冻性能。试验结果表明，玄武岩纤维的掺入明显提高了水泥稳定碎石的抗冻性，，由此，水泥稳定碎石可以更好地应用于我国北方寒冷地区。以上针对玄武岩纤维水泥稳定碎石的试验研究表明，玄武岩纤维不仅可以保证水泥稳定碎石的强度要求，而且可以提高其抗收缩性能以及抗冻性，使得水泥稳定碎石半刚性基层的路用性能更佳，一定程度上延长路面使用寿命，且玄武岩纤维造价低又环保，可以广泛应用至公路基层建设中。
[Abstract]:The comprehensive performance of cement stabilized macadam semi-rigid base has become the main application form of high grade highway now, but it also has some shortcomings. In this paper, it is faced with many problems such as poor shrinkage resistance and so on. By improving the properties of the material itself, that is, adding basalt fiber to the cement stabilized crushed stone, the road performance of semi-rigid base can be effectively improved on the premise that the strength is guaranteed. Through a large number of experiments, the basic mechanical properties, shrinkage properties and freezing resistance of basalt fiber cement stabilized macadam are systematically studied. The main contents are as follows: (1) the mixture ratio of basalt fiber cement stabilized macadam is designed by uniform test. Firstly, according to three influencing factors (cement dosage, fiber length, fiber dose), five groups of mix ratio are drawn up. The tensile strength and dry shrinkage coefficient of 7d without lateral limit and 7d splitting tensile strength and dry shrinkage coefficient were used as the evaluation index. The experiment consists of five groups of compaction tests (determination of optimal moisture content and maximum dry density), sample making and three evaluation index series tests. Finally, the regression model of three evaluation indexes is obtained by linear analysis. The optimum mix ratio of basalt fiber cement stabilized macadam and basalt fiber cement stabilized macadam was obtained. (2) aiming at basalt fiber cement stabilized macadam performance optimum mix ratio and non-fiber ordinary cement stability were obtained. The basic mechanical properties of the two groups were tested and studied. Including compressive strength and splitting tensile strength test. The changes of compressive strength and splitting tensile strength of two groups of cement stabilized macadam were studied by different curing ages, and the effects of basalt fiber on cement stabilized macadam were analyzed by comparison. The results show that The addition of basalt fiber can improve the strength of cement stabilized macadam. (3) the optimum mixture ratio of cement stabilized macadam with basalt fiber is studied by dry shrinkage test and temperature shrinkage test respectively. The shrinkage resistance of two groups of cement stabilized macadam and fiber free cement stabilized macadam. Series tests were carried out with different curing ages. The results show that the addition of basalt fiber can reduce the dry shrinkage coefficient and temperature shrinkage coefficient of cement stabilized macadam, and improve the shrinkage resistance of cement stabilized macadam. (4) Freeze-thaw test method with 28 days of curing age and 5 cycles of freezing and thawing cycle. The frost resistance of basalt fiber cement stabilized macadam was studied under the optimum mixture ratio of basalt fiber cement stabilized macadam and non-fiber ordinary cement stabilized crushed stone. The experimental results show that the addition of basalt fiber can obviously improve the frost resistance of cement stabilized macadam. Therefore, cement stabilized macadam can be better used in the cold region of northern China. The above experimental research on basalt fiber cement stabilized macadam shows that basalt fiber can not only guarantee the strength requirement of cement stabilized macadam, but also improve its shrinkage resistance and freezing resistance. It makes the pavement performance of cement stabilized macadam semi-rigid base better, prolongs pavement service life to a certain extent, and basalt fiber has low cost and environmental protection, so it can be widely used in highway base course construction.
【学位授予单位】：中国海洋大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U414

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