聚乙烯醇纤维水泥稳定碎石的疲劳性能研究

为研究掺聚乙烯醇纤维水泥稳定碎石的疲劳性能,首先根据聚乙烯醇纤维对水泥稳定碎石力学性能的影响规律,确定纤维最佳掺量和长度。基于间接拉伸疲劳试验和Weibull分布,对其疲劳寿命测试结果进行分析并建立疲劳方程。结果表明,聚乙烯醇纤维最佳掺量和长度为0.06%(质量分数)和24 mm;在最佳掺量和长度下,与未掺加纤维的水泥稳定碎石材料相比,聚乙烯醇纤维水泥稳定碎石的无侧限抗压强度提高约24%,劈裂强度提高约26%;对比不掺纤维的水稳碎石材料,其疲劳寿命也呈显著优势,当水泥用量为4%(质量分数)时,掺聚乙烯醇纤维与不掺纤维水泥稳定碎石斜率b之比为0.94~0.99,截距a之比为1.06~1.23。

Fatigue Properties of Polyvinyl Alcohol Fiber Cement Stabilized Crushed Stone

In order to study the fatigue performance of cement stabilized crushed stone mixed with polyvinyl alcohol (PVA) fiber, firstly, according to the influence law of polyvinyl alcohol fiber on the mechanical properties of cement stabilized crushed stone, the optimal fiber content and length were determined. Based on the indirect tensile fatigue test and Weibull distribution, the fatigue life test results were analyzed and the fatigue equation was established. The results show that the optimum content and length of PVA fiber are 0.06% (mass fraction) and 24 mm. Under the optimum content and length, the unconfined compressive strength of PVA fiber cement stabilized crushed stone increases by about 24%, and the cracking strength increases by about 26%, compared with the cement stabilized crushed stone material without fiber addition, basides its fatigue life also presents a significant advantage. When the cement mass dosage is 4%, the ratio of slope b of polyvinyl alcohol fiber-doped and non-fiber-doped cement stabilized crushed stone is 0.94~0.99, and the ratio of intercept a is 1.06~1.23.