Effect of asphalt-to-cement ratio on strength of cement asphalt mortar used in high-speed railway

The ballastless track structure (slab track) structure is commonly used in high-speed railway construction today. For this type of railway structure, the cement asphalt mortar polymer (CAM) layer plays an important role in damping, creating smoothness, reducing noise and ensuring simultaneous operation of the structure. Therefore, the CAM layer needs to be designed and manufactured to ensure ease of construction, strength and integrity for the entire slab track structure. This paper presents the initial experimental research results on the technology of CAM layer materials. The experimental studies were evaluated based on mixtures with asphalt/cement (A/C) ratios varying from 0.3, 0.4, 0.5, 0.6, and 0.7, respectively. The results of the research showed that, when the ratio of A/C increased, the flow time, flexural strength and compressive strength decreased. This trend of results was also completely consistent with the results of microstructural analysis by scanning electron microscope of mortar samples at 7 days of age