水泥稳定碎石基层材料抗冻性能研究

Study on Frost Resistance of Cement Stabilized Macadam Base Material in Winter

冬季道路工程施工过程中水泥稳定类基层材料早期强度增长缓慢且养生周期长,其抗冻性能经受严峻考验。采用自主研发的SES-Ⅰ型基层早强剂与水镁石纤维复掺以提高其适用性。通过抗冻性试验,以残留强度比(BDR)评价复掺早强剂与水镁石纤维条件下水泥稳定碎石性能变化规律;运用灰熵法及t检验分析了影响冻融循环作用下水泥稳定碎石抗冻性影响因素。结果表明:早强剂与水镁石纤维的出现对水泥稳定碎石抗冻性能的改善有积极影响,这与水镁石纤维的加筋效应及早强剂的微观提升效果有关。另外,水泥剂量和早强剂掺量对水泥稳定碎石抗冻性有显著影响,为推动水泥稳定碎石基层材料的全天候应用提供有益借鉴。

In winter,the early strength of the cement stabilized base material grows slowly and the curing time is long,and its frost resistance is severely tested.The self-developed SES-Ⅰearly strength agent is mixed with brucite fiber to improve its applicability.Through the frost resistance test,the residual strength ratio(BDR)was used to evaluate the change law of cement stabilized macadam under the condition of compounding early strength agent and brucite fiber.Then grey correlation entropy method and t-test were applied to analyze the significance of frost resistance influencing factors of the cement stabilized macadam under under freeze-thaw cycles such as the cement dosage,early strength agent dosage,fiber content and aggregate gradation.The results show that the compounding early strength agent and brucite fiber enhance the frost resistance of cement stabilized macadam.This is related to the reinforcing effect of brucite fiber and the micro enhancing effect of strong agent.Cement dosage and early strength agent dosage have significant influence on the frost resistance of cement stabilized macadam,which can provide useful reference for promoting the all-weather application of cement stabilized macadam base material.