石灰锶渣碎石基层混合料设计及性能评价

Design and Performance Evaluation on Mixture of Lime Strontium Ore Waste Slag Crushed Stone Base Course

针对锶渣在农村公路基层中的应用,通过不同级配碎石集料的对比试验,确定合理的石灰锶渣混合料的配合比,并选择其中两种合理的级配类型混合料,对混合料的无侧限抗压强度、劈裂强度、CBR值、水稳定性、收缩性能等主要的石灰稳定粒料类基层混合料的路用性能进行了研究。结果表明:石灰锶渣混合料劈裂强度与无侧限抗压强度具有相同的规律,细料越多,强度越高;确定合理的石灰锶渣混合料的配合比为石灰∶锶渣∶碎石=2∶8∶15;石灰锶渣碎石基层的CBR值为140%;浸水后石灰锶渣强度降低,龄期越长,水稳定性越好;石灰锶渣碎石基层随龄期会有轻微的膨胀,7d后体积趋于稳定;通过对比相同石灰剂量的石灰土的变形,石灰锶渣混合料的变形量较小,并且碎石比例越大,变形越小。

In regard with the application of strontium residue in the road base of rural roads,the reasonable mixture ratio of lime and strontium slag mixture is determined through comparisons and tests of different gradation crushed stone aggregate,and two types of graded mixture are selected to study the pavement performance of the lime stabilized gravel base mixture in terms of unconfined compressive strength,splitting strength,CBR value,water stability,and shrinkage etc.The results show that unconfined compressive strength and splitting strength of the lime and strontium slag mixture have the same rules,the more fine material the higher the strength is.The reasonable mixture ratio of lime and strontium slag mixture is determined that lime：strontium slag：crushed stone=2∶8∶15.The CBR value of the lime and strontium slag mixture is 140%.The strength of immersion lime strontium slag is decreased after submerging,and the water stability improves with age.Lime strontium slag crushed stone base has a slight expansion with age and the volume tends to be stable after 7 days.The deformation of the lime and strontium slag mixture is smaller by comparing the deformation of the lime soil with the same lime dose,and the greater the proportion of gravel the smaller the deformation is.