Forecast model on the transverse displacement of sea-shore mollisol subgrade under road foundation load effect

Abstract

The relationship between road foundation filling height (H) and the maximum transverse displacements of the subgrade (u), vertical settlement of ground center pile (s) is analyzed according to the on-site observation data of transverse displacement and vertical settlement on an expressway sea-shore mollisol subgrade during road foundation filling construction and after the completion of the project in Shandong Peninsula. The time-dependent changes of the data are also discussed. Based on the analysis, under road foundation load, the maximum displacement u and vertical settlements can be fitted in hyperbola. The calculation formula, from which road foundation maximum transverse displacement can be calculated according to vertical settlement of ground central stake is proposed. A forecast model is suggested to predict the maximum displacement of mollisol subgrade when it changes with time. Calculated results by using this model can reach agreement with the data from the project. For the common road foundation engineering without any pipe chute, the maximum transverse displacement can be calculated according to the vertical settlement of the ground media piles. It is suggested that the subgrade maximum transverse displacement should be controlled up to 0.2 cm per 24 hours in addition to the controlled mollisol subgrade road foundation fill rate regulated by Chinese Code.