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掺加纤维可有效改善水泥稳定碎石(CSM)基层材料的抗裂性并提高其强度。在依托室内物理试验研究纤维水泥稳定碎石(FCSM)路用性能的工作中,重要环节之一是如何提高纤维在混合料中拌和分散均匀性,这将显著影响测试试件的性能稳定性。为此,通过拌和工艺试验,分析了影响纤维拌和分散效果的主要因素及其作用机理,获得了合理的FCSM室内拌和工艺,并通过强度稳定性试验分析进行了印证,从而提出了FCSM拌和工艺效果的辅助判定方法。结果表明,纤维分散均匀性易受集料干湿状态影响:干拌时,搅拌片产生的空气流动易使纤维飘浮在干燥集料表面并逐渐聚集结团;湿拌时,干纤维易吸附于湿混合料的表面。对拌和效果影响而言,投料次序影响更为显著,而延长拌和时间虽能起到提高纤维分散效果的作用,但拌和达到一定时间之后其效果增加并不明显。合理的FCSM室内拌和工艺应首先将全部集料与水泥进行干拌15s后再洒水搅拌15s,然后撒入纤维终拌60s。材料的强度变异系数可表征试件性能的稳定性,可将其作为FCSM拌和效果的辅助判定方法。成果可为FCSM路用性能室内物理试验研究工作奠定基础。
Addition of fiber can effectively improve the crack resistance and increase the strength of the cement stabilized gravel (CSM) base material. One of the most important aspects in relying on the physical experiment of indoor fiber cement stabilized aggregate (FCSM) for road performance is how to improve the dispersion uniformity of the fibers in the mixture, which will significantly affect the performance stability of the test specimens. Therefore, the main factors influencing the mixing and dispersion of fiber and its mechanism were analyzed through the blending process test, and a reasonable FCSM indoor mixing process was obtained, and confirmed by the strength stability test and analysis, the effect of FCSM blending process Auxiliary decision method. The results showed that the uniformity of fiber dispersion was easily affected by the wet and dry state of the aggregate. When the dry mix was used, the air flow generated by the agitated sheet could easily float the fiber on the surface of the dry aggregates and gradually aggregate. Wet mix surface. The influence of mixing effect on the order of feeding is more significant, but to extend the mixing time can play a role in improving the fiber dispersion effect, but the mixing reaches a certain time after the effect is not obvious. Reasonable FCSM indoor mixing process should first of all the aggregate and cement dry mixing 15s and then sprinkle water for 15s, then sprinkle the final fiber mix 60s. The coefficient of variation of the material strength can be used to characterize the stability of the specimen performance, which can be used as a supplementary judgment method for the FCSM mixing effect. The results can lay a foundation for FCSM road performance indoor physics experimental study.