Abstract
The author performed a fundamental examination of the attenuation characteristics and resistance forces of the railway's ballast layer subject to traffic impact loads based on in-situ field measurements. The measurements were conducted by using high-performance three-dimensional sensing stones and a special sensing sleeper, which was developed to the distribution on the sleeper bottom of assess the dynamic pressure induced by running trains with a high frequency of up to several thousand Hertz. The measured results indicated that for the impact load components over 100 Hz, the ballast layer resists because of its high rigidity. The ballast layer can reduce the impact load amplitude to 1/3 – 1/5 per 10 cm of thickness. However, the ballast layer is almost non-resistant to the low-frequency load components with a frequency of 10 Hz or less and the low-frequency load components are not reduced.
