土工合成材料加筋桩支承路堤的离散元分析

Discrete element analysis of geosynthetic-reinforced pile-supported embankments

Kangyu Wang^a,b, Jun Cao^a, Jiahuan Ye^a,Ziliang Qiu^a, Xinquan Wang^c,d,e*

研究内容

Abstract: A discrete element trapdoor model wasestablished using the MatDEM software, and the effects of different embankmentand reinforcement heights on the soil arching effect of embankments underreinforced conditions were investigated by introducing a biaxial geogrid. Theoutcomes demonstrated that the inclusion of a geosynthetic reinforcement couldenhance the load transfer efficacy of the embankment and thereby reduce the differentialsettlement of the embankment surface. The differential settlement could bereduced by approximately 50 % when the reinforcement height and the pile capwere close. The inclusion of the geosynthetic reinforcement helped reduce thedevelopment of the slip surface within the embankment above the reinforcement andprevented the vertical slip surface from continuing to move upwards, thusensuring that the soil arching effect did not degrade too quickly and continuedto play a role. In the case of a low embankment reinforcement, the soil archingeffect was largely nonfunctional because of the rapid development of thevertical slip surface, and the load on the embankment in the soft soil wasmainly transferred to the piles through the tensioned membrane effect of thegeosynthetic reinforcement. For a high embankment with a low reinforcement height,the soil arch structure of the embankment was well maintained, the soil archingeffect did not degrade, and the load on the embankment in the upper part of thesoft soil was transferred to the piles via the soil arching effect along withthe tensioned membrane effect. In the case of a high embankment with a highreinforcement, the reinforcement blocked the vertical slip surface only for thesoil above the reinforcement height, whereas the vertical slip surface belowthe reinforcement height developed in line with that of the same height, whenthe tensioned membrane effect and soil arching effect worked together in theembankment above the reinforcement height, and the soil arching effect belowthe reinforcement height degraded and hardly played a role.

Keywords: Soil arching effect; MatDEM; Discrete element method; Geosynthetic

Fig. 8 DEM model of a geogrid-reinforced piled embankment (Unit: mm).

Fig. 10 Comparison between displacement contours obtained from laboratory tests and DEM model (Δs=30 mm).

Fig. 14 Displacement distribution diagrams (unit: mm) (Δs=30 mm): (a)–(e) Deformation of the embankment soil; (f)-(h) Vertical displacement cloud diagrams at the reinforcement height.

Fig. 15 Horizontal and vertical displacements contours of the embankment for a trapdoor displacement Δs=20 mm.

Fig. 18 Contact force chains for DT1: (a) Δs=0 mm; (b) Δs=2 mm; (c) Δs=4 mm; (d) Δs=6 mm; (e) Δs=8 mm; (f) Δs=10 mm; (g) Δs=15 mm; (h) Δs=20 mm.

Wang, K., Cao, J., Ye, J., Qiu, Z., & Wang, X. (2024). Discrete element analysis of geosynthetic-reinforced pile-supported embankments. Construction and Building Materials, 499, 138448.

https://doi.org/10.1016/j.conbuildmat.2024.138448