基于浆体的水泥粉煤灰稳定碎石力学特性预估

Prediction on mechanical properties of slurry-based and cement-fly ash-stabilized macadam

为了了解浆体对水泥粉煤灰稳定碎石力学性能的影响,首先研究了不同配比下水泥粉煤灰浆体与水泥粉煤灰细集料浆体强度特性,分析了浆体强度和龄期对水泥粉煤灰碎石整体力学特性的影响及其相关性,进而实现了基于浆体强度的水泥粉煤灰稳定碎石力学特性预估。结果表明:水泥粉煤灰浆体强度随龄期增长和水泥—粉煤灰掺量比降低而增大;在60 d前,水泥粉煤灰细集料浆体强度随龄期和细集料—粉煤灰掺量比的增长而增大,之后,随细集料—粉煤灰掺量比的增长而先增大后减小;浆体强度与水泥粉煤灰稳定碎石力学特性具有较高相关性;提出的预估方程符合水泥粉煤灰稳定碎石强度变化规律,具有明确的物理意义。建议水泥粉煤灰稳定碎石内掺粉煤灰掺量为4%～6%,外掺水泥剂量为3%～4%。

In order to reveal the influence of slurry strength on cement-fly ash-stabilized macadam performance, strength characteristics of cement-fly ash slurry and cement-fly ash fine aggregate slurry of different proportion were studied. The influence of slurry strength and age on the mechanical properties of the cement-fly ash gravel was analyzed. Finally, the mechanical properties of slurry strength based and cement-fly ash stabilized macadam was predicted. The results indicate that along with the increase of age and the decrease of dosage ratio of cement-fly ash, the strength of fly ash ce- ment slurry increases ; in the first 60 d, along with the increase of age and dosage ratio of fine aggregate-fly ash, the strength of cement-fly ash fine aggregate slurry increases; after 60 d, the strength of cement-fly ash fine aggregate slurry increases first and then decreases with the increase of the dosage ratio of fine aggregate-fly ash; there is a high correlation between the slurry strength and the mechanical properties of cement-fly ash stabilized macadam; the proposed prediction equation has clear physical meaning and correlates well with the strength change of cement-fly ash stabilized macadam ; in cement-fly ash stabilized macadam, the suggested proportions of fly ash and cement are 4% ~ 6% and 3% ~ 4% , respectively.