Analysis of Deformation Characteristics of Filled Subgrade Treated by Micro‐Pile

Abstract

Deformation control of fill subgrade is a difficult point in the field of highway engineering. This article relies on the treatment project of micro-piles for subgrade deformation of K555 + 070～K557 + 710 section of Qingdao-Yinchuan Expressway. Settlement and stress monitoring was carried out at the toe of the roadbed, the shoulder, and the center of the roadbed. We use Midas/GTS modeling trial calculation. A new method to check the simulation results of the deviation rate is proposed. A calculation model of the stress and deformation of the subgrade in the whole life cycle is established. The results of comparative analysis, monitoring, and simulation are as follows. ① The compression and consolidation of the fill account for most of the settlement and deformation of the roadbed in the whole life cycle. ② Subgrade center settlement is the sensitive part of subgrade deformation. ③ After piles are added, the deformation extremes at the toe of the slope, the shoulder, and the center of the roadbed are all reduced by more than 96%. The research results can provide theoretical guidance for the analysis of the stress and deformation characteristics of the subgrade before and after the micro-pile treatment.