摘要
为了促进低剂量水泥改性级配碎石在工程中的推广应用,通过无侧限抗压强度和劈裂强度试验,确定了低剂量水泥改性级配碎石的抗剪强度指标,对比分析了级配、龄期、水泥剂量、压实度及含水量对抗剪强度的影响。研究结果表明:级配对强度的影响显著,嵌挤骨架密实型混合料强度最高,粗集料过多不利于粘聚力,细集料过多不利于内摩阻角。粘聚力随着龄期、水泥剂量及压实度的增加而增加。随着含水量的增加,粘聚力呈现出驼峰变化规律,在最佳含水量附近达到峰值。随着龄期、水泥剂量、压实度及含水量的增加,内摩阻力呈现一种驼峰变化规律,在2%水泥剂量和最佳含水量条件下达到峰值。SAC级配设计方法可用于高强度的低剂量水泥改性级配碎石设计。
In order to promote the popularization and application of low-dose cement-modified graded crushed rock in engineering,the effects of the graduation,the age,cement dosage,the degree of compaction and water content on shear strength are compared and analyzed by using unconfined compressive strength and splitting strength test which can determine the shear strength index of the low-dose cement-modified graded crushed rock.The results show that the gradation has remarkable effect on strength and built-in skeleton-density gradation has the highest strength.However,the excessive coarse aggregate is not conducive to cohesion and the excessive fine one is not instructive to the angle of internal friction.The cohesion increases with the increase of the age,cement dosage and the degree of compaction.With the increase of water content,there appears the variation like hump,and it reaches the peak near the optimal water content.The angle of internal friction increases with the increase of the age,cement dosage,the degree of compaction,and water content,there is the regular of hump,the cement dosage is 2%and optimal water content appears at the peak.The methods of SAC gradation design can be used for the gradation design of high strength low-dose cement-modified graded crushed rock.
作者
周志刚
刘鑫
孙绪康
ZHOU Zhi-gang;LIU Xin;SUN Xu-kang(Key Laboratory of Road Structure and Material Transportation Industry,Changsha University of Science&Technology,Changsha 410114,China)
出处
《交通科学与工程》
2019年第1期8-14,共7页
Journal of Transport Science and Engineering
基金
国家自然科学基金资助项目(51378084)
广西交通科技计划项目(桂交综合发[2010]109号)
关键词
低剂量水泥改性级配碎石
抗剪强度
影响因素
级配
low-dose cement-modified graded crushed rock
shear strength
influence factors
gradation
