沥青损伤愈合性能试验研究

发布时间：2018-05-04 09:26

本文选题：基质沥青 + 损伤愈合能力　；参考：《湖南大学》2014年硕士论文

【摘要】：从源头上看，沥青混合料之所以具有损伤愈合性能是因为沥青这种特殊的粘弹性材料的存在。因此从沥青层面上对其损伤愈合性能进行分析是对沥青混合料进行研究的基础，且更具有可行性。本文在借鉴前人已有研究成果的基础上，从最基本的基质沥青出发，尝试以不同试验方法来对其自身具备的损伤愈合性能及损伤愈合机理进行研究，并探讨了外加剂对于沥青损伤愈合性能的影响。（1）在充分学习、借鉴前人对沥青损伤愈合性能的研究成果的基础上，分析并总结了影响沥青损伤愈合性能的主要因素、影响效果和研究试验方法。（2）采用延性拉伸愈合（DTH）试验方法，以在一定条件下恢复后的沥青试件拉伸长度与原状试件的拉伸长度比作为愈合率的评价指标，比较不同影响因素对基质沥青损伤愈合性能的影响。（3）引入双片组愈合（TPH）试验，采用动态剪切流变仪(DSR)对纯沥青的损伤愈合能力进行研究。试验过程中，将两片独立的沥青片放置在仪器平行的两端，通过挤压调整试件间距来模拟愈合过程，，试验将双片组试件的愈合过程划分为初始愈合阶段和时间依赖愈合阶段，试验结果总结如下：（a）在初始愈合阶段，随着间距缝隙的逐渐减少，试件模量的增长可以划分为三个阶段；（b）在时间依赖愈合阶段，两种模式下即间距保持不变模式和应力保持不变模式下，试验结果有很大的差异，试验结果显示，压应力对损伤试件的愈合促进扮演着很重要的角色；（c）对可能影响试验结果的一些因素进行了探讨。（4）通过SBS改性沥青的延性拉伸愈合（DTH）试验，证实SBS改性沥青同样能实现损伤愈合，愈合程度跟恢复时间和恢复温度有关。在同等条件下，本次试验所采用的SBS改性沥青恢复状况不如基质沥青。通过双片组愈合（TPH）试验，证实在粉胶比为1.0，以复模量比为唯一评价指标，沥青胶浆的愈合性能不如纯沥青试件。
[Abstract]:From the source, the asphalt mixture has the damage healing property because of the existence of asphalt as a special viscoelastic material. Therefore, the analysis of its damage healing performance from the asphalt layer is the basis of the study of asphalt mixture, and is more feasible. Based on the previous research results and the most basic asphalt matrix, this paper attempts to study its own damage healing performance and mechanism with different test methods. The effect of admixture on asphalt damage healing performance was also discussed. 1) on the basis of fully studying and referring to the previous research achievements on asphalt damage healing performance, this paper analyzes and summarizes the main factors affecting asphalt damage healing performance, the effects and experimental methods. (2) using the method of ductile tensile healing (DTH) test, the ratio of tensile length of asphalt specimen recovered under certain conditions to that of undisturbed specimen is taken as the evaluation index of healing rate. The effects of different factors on the damage healing performance of asphalt matrix were compared. The damage healing ability of pure asphalt was studied by using dynamic shear rheometer (DSRs). During the experiment, two independent bitumen sheets were placed at the parallel ends of the instrument, and the healing process was simulated by squeezing and adjusting the spacing of the specimens. The healing process of the two groups of specimens was divided into the initial healing stage and the time-dependent healing stage. The experimental results are summarized as follows: (1) in the initial healing stage, with the decrease of gap spacing, the increase of specimen modulus can be divided into three stages: 1) in the time dependent healing stage, There are great differences between the two modes, that is, the interval invariant mode and the stress invariant mode. The experimental results show that, Compressive stress plays an important role in promoting the healing of damaged specimens. 4) through the ductile tensile healing test of SBS modified asphalt, it is proved that SBS modified asphalt can also achieve damage healing, and the healing degree is related to recovery time and recovery temperature. Under the same conditions, the SBS modified asphalt used in this experiment is not as good as the base asphalt. The results of TPH test show that when the ratio of powder to binder is 1.0 and the ratio of complex modulus is the only index, the healing performance of asphalt mortar is not as good as that of pure asphalt sample.
【学位授予单位】：湖南大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U414

【参考文献】