Settlement Characteristics and Prediction of Weak Expansive Soil Subgrade Based on Track Geometry Measurements

Abstract

Abstract The weak expansive soil subgrade of the railway in operation is prone to settlement in a high-temperature climate, which results in a rapid deterioration in the geometric dimensions of the track, and affecting the safety of the train operation. This paper uses Track Geometry Measurements (TGM) to analyze the deterioration characteristics of track geometry parameters in the subgrade settlement of weak expansive soil. Also establishes a Settlement Prediction Model (SPM) to identify the settlement time of subgrade and predict the value of track geometry parameters before track maintenance. SPM applies to the mileage k285+000∼k300+000 of the weakly expansive soil subgrade section of the Han-Dan Railway. It was verified by the TGM of the 20 subgrade settlement positions of this section. The results show that SPM has a high application value.