基于CAVF法的高寒地区水泥稳定碎石基层设计及其性能

荆强强¹，李传海²，张荣华³，乔鸿超³

1.山东高速基础设施建设有限公司，山东 济南  250014；2.山东高速工程检测有限公司，山东 济南  250002；

3.山东高速建设管理集团有限公司，山东 济南  250014

摘要：为提高水泥稳定碎石基层在高寒地区的适用性，提出一种适用于高寒地区水泥稳定碎石的主骨料空隙填充（coarse aggregate voids-filling，CAVF）法。通过击实试验、无侧限抗压强度试验、冻融循环试验和温缩试验验证CAVF法设计水泥稳定碎石混合料的力学性能、抗冻性能和温缩性能。结果显示：水泥稳定碎石混合料的最佳含水率和最大干密度均随水泥稳定碎石混合料设计空隙率绝对值的增大而增大；力学性能试验结果显示设计空隙率绝对值从0增至10%，水泥稳定碎石混合料的7 d无侧限抗压强度提高23.5%；采用CAVF法设计的水泥稳定碎石混合料的残留抗压强度比均超过90%，且随设计空隙率绝对值的增大而提高；在温度为-20~40 ℃内，水泥稳定碎石混合料的温缩系数变化较小，可有效避免水泥稳定碎石基层发生温缩开裂。调整设计空隙率的CAVF法可用于设计水泥稳定碎石混合料，提高路用性能。

关键词：水泥稳定碎石;主骨料空隙填充法;无侧限抗压强度;抗冻性能;温缩性能

Design of cement stabilized in alpine area based on CAVF method and its performance

JING Qiangqiang1, LI Chuanhai2, ZHANG Ronghua3, QIAO Hongchao3

1.Shandong Hi-Speed Infrastructure Construction Co., Ltd., Jinan 250000, China;

2. Shandong Hi-Speed Engineering Test Co., Ltd., Jinan 250002, China;

3. Shandong Hi-Speed Construction Management Group Co., Ltd., Jinan 250014, China

Abstract:In order to improve the applicability of cement stabilized macadam base in alpine areas, a coarse aggregate void-filling (CAVF) design method is proposed. The mechanical properties, frost resistance and temperature shrinkage properties of the cement stabilized crushed stone mixture designed by CAVF method are verified by compaction test, unconfined compressive strength test, freeze-thaw cycle test and temperature shrinkage test. The results show that, the optimal water content and maximum dry density of the cement stabilized macadam both increase with the increase of the absolute value of the design porosity. The mechanical properties test results show that, the absolute value of the design void ratio increases from 0 to 10%, and the seven-day unconfined compressive strength of the cement stabilized macadam increases by 23.5%. In the temperature range from -20~40 ℃, the temperature shrinkage coefficient of the cement stabilized macadam changes slightly, which could effectively avoid the thermal shrinkage cracking of the cement-stabilized macadam base. Therefore, the CAVF method of adjusting the design porosity could be used to design the cement-stabilized macadam.

Keywords:cement stabilized macadam; CAVF method; unconfined compressive strength; frost resistance; temperature shrinkage property