Analysis of Settlement Behaviour of Soft Ground Under Wide Embankment

Abstract

An elastoplastic numerical model for calculating the consolidation settlement of wide embankment on soft ground is established using PLAXIS finite element software to investigate the settlement behaviour of soft ground under the wide embankment. The distribution rules are analysed and compared to narrow embankments, such as surface settlements of ground and embankment, lateral displacement of soft ground at the foot of embankment slope and excess pore pressure in soft ground. The influence rule of elastic modulus of soft ground on the settlement of soft ground under wide embankment is discussed. The results show that the settlement distributions of wide and narrow embankments on soft ground are “W” and “V” shapes, respectively. The maximum settlement of wide embankment is near the foot of the embankment slope, which is unequal to the settlement at the centreline of the embankment. The lateral displacement distribution rules of soft ground are both “belly” shaped at the foot of two types of embankments slope. However, the lateral displacement of the wide embankment is larger in each corresponding stage. During the construction period, the excess pore pressure in the soft ground under the wide embankment is much higher than that of the narrow embankment, so the post-construction consolidation time of the wide embankment is longer. Moreover, the macroscopic settlement rule of the wide embankment is still the same with the increase of elastic modulus of soft ground.

A Novel Approach to Determine the Treatment Range of Prefabricated Vertical Drains and Cement‐Soil Mixing Piles for Wide and High Embankment on Soft Ground

“…The width of the embankments can reach tens or even hundreds of meters. These wide and ultra-embankment projects are mainly distributed on multi-lane or even supermulti-lane expressways (e.g., Shuijing-Guanjingtou Expressway in Shenzhen, China, embankment width: 200 m), the railway station (e.g., Jinan West Passenger Station of Beijing-Shanghai High-speed Railway, embankment width: 200 m), airport runway, taxiway, apron (e.g., Shenzhen Airport, embankment width: 400 m), metro vehicle depot (e.g., Guangzhou Metro Vehicle Depot, embankment width: 52-72 m) [6,7] etc. For wide embankments, previous studies have shown that the maximum settlement of the embankment no longer occurs at the centerline of the embankment due to the shear displacement generated near the foot of the ramp, but transfers to two sides.…”

“…For wide embankments, previous studies have shown that the maximum settlement of the embankment no longer occurs at the centerline of the embankment due to the shear displacement generated near the foot of the ramp, but transfers to two sides. That is to say, the settlement of narrow embankment is V-shaped, however, the settlement of wide embankment is W-shaped, [6,[8][9][10][11] as shown in Figure 1. The result has been thoroughly verified by indoor geotechnical centrifugal model test, field observation, and numerical simulation.…”

“…The studies have shown that for wide embankments on soft ground, the maximum settlement will shift from the centerline of the embankment to both sides. [6,49] Figure 11 presents the distribution curves of the post-construction settlement along the width of the ground surface under six working conditions. It can be seen that the post-construction settlement is the minimum when the R t is 0:5 (i.e., treated with CSMPs only).…”

Numerical Analysis of Differential Settlement in Road Due to Widening Considering Different Reinforcement Techniques

“…The differential settlement increases with increasing groundwater level and subgrade height [27]. The differential settlement creates a soil arching effect in the embankments [28], which is higher at the edge of the slope than at the centerline [29]. Aiming at the above-mentioned issue, this research is based on the road widening project of National Highway-120 (N-120), Sindh, Pakistan.…”

Settlements of Embankments on Different Types of Soils

“…al,(2013) 7 explained the improvement in reinforcement rigidity was explained.It leads to a decrease in lateral displacements but not settlements and increases the structures' stability.Chin et.al, (2016) 8 explained the effective ground treatment using prefabricated vertical drains and geogrids measured settlements more than the calculated settlements.Suresh et. al, (2020) 9 explainedthat the lateral pressures and deformation along the depth are analyzed in this paper.Fu et.al, (2021) 10 explained thata wide embankment has lower settlements than a narrow embankment. A wide embankment has more excess pore water pressure than a narrow embankment.Kommu et.…”