Analytical solution for the response of an existing tunnel to a new tunnel excavation underneath

Zhang, Dong Ming; Huang, Zhong-Kai; Li, Zili; Zong, Xiang; Zhang, Dongming

doi:10.1016/j.compgeo.2018.12.026

Cited by 112 publications

(41 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We first verified our method by conducting two examples. Two projects of Shanghai shield tunnels crossing existing tunnels in the literature [36,37] were selected for comparison.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Settlement of an Existing Tunnel Induced by Crossing Shield Tunneling Involving Residual Jacking Force

et al. 2022

View full text Add to dashboard Cite

An analytical formulation involving residual force is proposed to predict the displacement of an existing structure by simplifying the tunnel as an infinite Euler–Bernoulli beam resting on a two-parameter Pasternak foundation. The feasibility is confirmed by two actual measurements at sites in the published literature. Parametric studies—including consideration of jacking force alone, jacking force and ground loss, and jacking force and equivalent bending stiffness—are carried out to study the influence on the deformation of the existing tunnel. The results show that the residual jacking force can decrease the settlement of the existing tunnel, but the significance of its effect varies under different engineering conditions. With the increase in ground loss, the beneficial effect of jacking force in preventing further aggravation of tunnel settlement gradually becomes obvious, and the jacking force can reduce the deformation more effectively when the tunnel has lower bending stiffness. As a result, it is recommended that some effective measures should be adopted to maintain sufficient residual jacking force in the segments, so as to prolong the life of the tunnel.

show abstract

“…We first verified our method by conducting two examples. Two projects of Shanghai shield tunnels crossing existing tunnels in the literature [36,37] were selected for comparison.…”

Section: Resultsmentioning

confidence: 99%

“…Firstly, a new tunnel crossing an existing tunnel in Shanghai [36] was selected as an example. The two tunnels are designed to be almost perpendicular.…”

Section: Casementioning

confidence: 99%

Settlement of an Existing Tunnel Induced by Crossing Shield Tunneling Involving Residual Jacking Force

et al. 2022

View full text Add to dashboard Cite

show abstract

“…Wu et al 8 proposed a soil–tunnel interaction model based on the Timoshenko beam theory 9 and discussed the effect of the equivalent shear stiffness and the rotational stiffness of the joint between soil and station. Furthermore, Zhang et al 10 adopted the Kerr foundation in the soil–tunnel interaction to calculate more realistically, which can consider the compression and shear response of the ground superior to conventional Winkler or Pasternak foundation model.…”

Section: Introductionmentioning

confidence: 99%

A case study of newly tunnels over-crossing the existing subway tunnels

Liu

Shi

et al. 2022

International Journal of Distributed Sensor Networks

View full text Add to dashboard Cite

Due to the continuous expansion of congested urban areas, many new tunnels are inevitable to over-cross the existing subway lines and may even affect the operation of existing lines. It is vital to investigate the response of existing tunnel caused by over-crossing tunneling. In this study, a case history of closely spaced twin tunnels excavated above the existing tunnels in soft soil stratum was presented. The deformation of the existing tunnels induced by the excavation of the new tunnels was automatically monitored. In-situ monitoring results showed that the vertical displacement of the existing tunnels was mainly uplift and its development showed obvious phase characteristics. The increase rate of the vertical displacement in Phase I and II induced by the second over-crossing was smaller than that of the first over-crossing. A superposition method was employed to describe the uplift section characteristics of the existing tunnels. The influence ranges of tunnel excavation on the left and right lines of the existing tunnels were approximately 5.5D and 4.5D, respectively. The torsional deformation of the rail bed and the convergence of the existing tunnels are explored, and the reasons for the changes of the over-crossing sections are analyzed at the same time.

show abstract

“…Theoretical analytical and model test methods have been commonly used to study tunnel interactions in the past. Based on the Timoshenko beam correlation theory on a Kerr foundation, Zhang et al [18] established an analytical solution for the existing tunnel's response caused by new tunnel excavation, and the analytical solution was verified, followed by a parametric analysis, which showed that the tunnel's longitudinal shear stiffness had a significant effect on the existing tunnel's response. In the context of a shield connection project of the Beijing subway, Tao et al [19] combined the results of theoretical analysis, numerical simulation and field measurement to investigate the effects of new shield tunnel construction on longitudinal and transverse displacements, additional bending moments and the axial forces of the existing shield tunnel.…”

Section: Introductionmentioning

confidence: 99%

Model Test on Approaching the Construction of Multi-Line Overlapping Shield Tunnels for Up- and Down-Crossing

et al. 2022

View full text Add to dashboard Cite

Multi-line overlapping shield tunnels have a complicated layout in the underground space, and the interaction mechanism between tunnels is very complicated. Based on the construction formation of multi-line overlapped shield tunnel with short-distance up- and down-crossing, indoor model tests were conducted to analyze ground settlement (caused by excavation unloading and stratum loss) and the longitudinal deformation law of existing tunnels based on the drainage method, according to the characteristics and control requirements of the short-distance construction of shield tunnels. The results show that as long as the construction strategy of first-down and then-up crossing is adopted, no sudden change in ground settlement would occur. Furthermore, neither the changes in transient settlements nor the final ground settlement would be too large, which is different from the strategy of first-up and then-down crossing; the first-up and then-down crossing strategy generally increases the curvature of the deformation curve of the existing tunnel, and the deformation of the existing tunnel will cause obvious repeated vibrations. This provides theoretical guidance for the design and construction of multi-line overlapped tunnels.

show abstract

Analytical solution for the response of an existing tunnel to a new tunnel excavation underneath

Cited by 112 publications

References 43 publications

Settlement of an Existing Tunnel Induced by Crossing Shield Tunneling Involving Residual Jacking Force

Settlement of an Existing Tunnel Induced by Crossing Shield Tunneling Involving Residual Jacking Force

A case study of newly tunnels over-crossing the existing subway tunnels

Model Test on Approaching the Construction of Multi-Line Overlapping Shield Tunnels for Up- and Down-Crossing

Contact Info

Product

Resources

About