Carbonate gravels are often used as a road base filling material in island area. To evaluate the feasibility of carbonate gravels as a filling material, a large-diameter cyclic triaxial testing system (LDCTTS) was adopted to investigate the particle breakage and long-term behavior of carbonate gravels under high-cycle loadings (N = 50000). The effects of cyclic deviatoric stress, initial static deviatoric stress, effective confining pressure and drainage conditions on the long-term behavior of carbonate gravels were investigated. Fractal theory and Einav’s relative breakage index were applied for the analysis of particle breakage. Test results show that the accumulated axial strain of carbonate gravels increases with the increase of cyclic deviatoric stress and initial deviatoric stress. Particle breakage occurs during the cyclic loading tests, especially for coarse particles with diameter>10 mm. The relative breakage index increases linearly with the cyclic deviatoric stress and the initial deviatoric stress, while decreasing exponentially with the effective confining pressure for the stress range studied. In addition, carbonate gravels in undrained tests exhibit more crushing than drained tests due to the positive pore water pressures accumulated. Einav’s relative breakage index is found to be in an exponential relationship with the input of plastic deformation energy, which can be used to predict the particle breakage of carbonate gravels under cyclic loadings.

碳酸盐砾石常被用作海岛地区的路基填筑材料。为了评估碳酸盐砾石作为充填材料的可行性，采用大直径循环三轴试验系统（LDCTTS）研究了碳酸盐砾石在高循环载荷下的颗粒破碎和长期行为（N = 50000）。研究了循环偏应力、初始静偏应力、有效围压和排水条件对碳酸盐砾石长期行为的影响。分形理论和Einav的相对破碎指数被应用于颗粒破碎的分析。试验结果表明，碳酸盐砾石的累积轴向应变随着循环偏应力和初始偏应力的增加而增加。循环加载试验中会发生颗粒破碎，尤其是对于直径>10 mm 的粗颗粒。相对断裂指数随着循环偏应力和初始偏应力线性增加，而随着所研究应力范围的有效围压呈指数下降。此外，由于累积的正孔隙水压力，不排水测试中的碳酸盐砾石比排水测试表现出更多的破碎。发现 Einav 的相对破碎指数与塑性变形能的输入呈指数关系，可用于预测循环载荷下碳酸盐砾石的颗粒破碎。