The Stress Distribution in Airport Runway Subgrade Subjected to Airplane Moving Loads

Abstract

The calculation of stress distribution in subgrade subjected to an airplane load is crucial to the design of airport runway. Utilizing the Boussinesq’s solution and integration method, this paper analyzes the stress variation in a soil element of subgrade caused by the passage of a moving airplane. The obtained results show the stress variation as the airplane moves on the ground surface; the development of the heart-shaped stress path in the deviator stress space is clearly shown. In the case of multiple soil layers ground covered with a rigid pavement, the finite element method is adopted to calculate the stress distribution. Comparing the analytical solution with numerical results, the theoretical model can capture the stress distribution in the vertical direction. Analysis indicates that the upper rigid pavement can significantly reduce the maximum stress in subgrade. Therefore, it is proven an effective way to control the settlement of subgrade by enhancing pavement.