Effect of Tunnel Progress on the Settlement of Existing Piled Foundation

Abstract

Tunnel construction below or adjacent to piles will affect the performance and eventually the stability of piles due to ground deformation resulting in the movement of piles and changes in the axial force distribution along the piles. A three dimensional finite element analysis using PLAXIS 3D (2013) was performed to study the behaviour of a single pile and 3 x 3 piles group during the advancement of shield tunnelling in ground. The 10-node tetrahedral elements were used to model both the soil and the tunnel lining. The Hardening Soil (HS) model was used to simulate the soil structure interaction at the tunnel-soil interface. An isotropic elastic model was used for the pile, piles cap, tunnel lining and tunnel boring machine shield (TBM). Several parametric studies were attempted including the longitudinal, lateral, and vertical tunnel location relative to pile embedded in different types of soil (clay or sand). The results showed that the pile head settlement increases during the tunnelling advancement in larger values than that for ground surface settlement. A zone of influence was determined in the range of twice the tunnel diameter in the longitudinal direction (forward and backward of the pile), and transverse direction (left and right of the tunnel centreline). If the tunnel boring is kept off this zone then there is no fear of pile collapse.

Numerically liquefaction analysis of tunnel‐sand pile interaction (TSPI) under seismic excitation

“…During liquefaction, soil loses its shear strength to act like fluid, and other structures cause the soil medium to fluctuate heavily if the full state of the fluid exists; in addition, the soil medium shows uplift which was described by the several researchers [1][2][3][4][5][6]. Uplift due to liquefaction is observed from three different techniques such as experimental, analytical, and numerical analysis while obtained results of these methods are close to each other which convince the standard level of accuracy; however, in tunnel-soil pile interaction, tunnel and pile behave as rigid elements, and soil acts as a flexible element [7][8][9][10][11][12]. So, the seismic force-resisting capacity of tunnel and piles is lower than soil because of the radiation damping properties of the soil; in this point of view, the majority percentage of seismic excitation is resisted by soil; therefore, other underground structures in the soil medium such as tunnels and piles are less damaged.…”

Impact of Double Shield Tunnel Construction on Adjacent Pile Foundation in Silty Fine Sand Strata

“…Many researchers reported that the settlement of the pile was closely related to the geometric parameters of piles and tunnels by many researches (Liu et al, 2014;Al-Omari et al, 2019;Ayasrah et al, 2021). However, the specific effect regularity is still unclear concerning the geometric parameters of piles and tunnels on the pile foundations.…”

“…It was found that the settlements of pile foundation and pile perimeter soil surface were closely related to the relative position between piles and tunnels, and the pile perimeter soil settlement was mainly responsible for the pile foundation tilting (Boonyarak et al, 2014;Dias et al, 2015;Wang et al, 2018). Moreover, factors such as pile top load, ground loss, soil strength, grouting pressure, pile size, and tunnel diameter were considered as the dominant factors of the internal stress and deformation of pile foundation (Lee, 2013;Liu et al, 2014;Huang et al, 2021;Al-Omari et al, 2019;Jeon et al, 2020;Ayasrah et al, 2021;Zhang et al, 2022). Furthermore, it was investigated that the isolation pile reinforcement can strengthen the whole pile foundation, it had obviously better reinforcement effect than grout reinforcement and longeron cross bracing reinforcement (Park et al, 2015;Li et al, 2020;Lv et al, 2020;Li et al, 2021).…”

Mechanical Responses of Slurry Shield Underpassing Existing Bridge Piles in Upper-Soft and Lower-Hard Composite Strata

“…Many scholars have conducted studies on the mechanical responses of shields underpassing pile foundations. These include (among others) theoretical [1][2][3], experimental [4][5][6][7], and numerical simulation studies [8][9][10]. Zhao [11] analyzed the lateral and axial responses of pile foundations owing to tunnel excavation using a two-stage method.…”