Deformation properties of decomposed peat under vibration and dynamic load impact

Deformation of embankments built on marshy territories is mainly displayed by slowly increasing residual settlements and significant elastic settlements. These cause intensive wear of fastening elements and prove the definitive role of peat used as foundation material in the reliable performance of railway track in general. Investigation of peat physical and deformation characteristics were conducted on samples having undisturbed structure. The result of experiments were obtained the following dependencies: E(W) - dependence of aggregate deformation modulus on natural moisture level; E(rho(d)) - dependence of aggregate deformation modulus on porosity. Analysis of the obtained data allows to draw a conclusion, that peat porosity growth at low values of moisture leads to significant reduction of deformation modulus. It is also worth mentioning that the impact of vibration and dynamic loading increases this reduction even further. The described findings emphasize the importance of taking into consideration vibration and dynamic loads when calculating settlements in railway embankments built on peat foundations. (C) 2017 The Authors. Published by Elsevier Ltd.