Lateral deformation of embankment with the CFG pile-net structure for Yun-Gui passenger dedicated line

作者：Pan, Gao-Feng; Liu, Xian-Feng; Yuan, Sheng-Yang; Sun, Dan-Xi; Tian, Mao-Cheng; Wang, Yi-Bo; Feng, Yan; Jiang, Guan-Lu

来源：Yantu Lixue/Rock and Soil Mechanics, 2020, 41: 154-164.

DOI：10.16285/j.rsm.2020.0126

• Compare and analyze
• Composite foundations
• Construction design
• Deformation analysis
• Foundation settlement
• Lateral displacements
• Linear relationships
• Passenger dedicated line

Taking cement flyash gravel(CFG) pile-net structure embankment in the expansive soil area of the Yun-Gui (i.e., Yunnan-Guangxi) passenger dedicated line as the engineering background, a full-scale on-site embankment filling test was carried out to compare and analyze the lateral deformation law of the natural foundation and CFG pile-net composite foundation under the subgrade load. The results show that (1) the maximum lateral deformation of the natural foundation occurs at 1-2 m depth below the surface, while the maximum lateral deformation for the composite foundation appears at the depth of 0.6 times of the pile length, and the constraint effect of increasing the pile length on the lateral deformation is only obvious within the depth of 6 m. (2) The maximum lateral deformation has a linear relationship with the foundation settlement in stages. After the embankment exceeds a certain critical height, the lateral deformation develops sharply. (3) The critical filling height of the composite foundation decreases with the increase of pile length but the maximum lateral displacement decreases after stabilization. Finally, based on the hypothesis of lateral deformation stratification analysis and equal volume deformation, the method of predicting the lateral deformation of the foundation is proposed based on the measured soil parameters, and the accuracy is verified by the measured data. The research results can provide the theoretical reference for the construction design and deformation analysis of CFG pile-net structure roadbed.