This paper examines the effect that tunnel size, depth and volume loss have on greenfield soil displacements above tunnels in sandy ground. The results of a series plane-strain centrifuge tests performed dry silica sand are examined. cover-to-diameter ratio, C/D, ranged from 1·3 to 4·4. Features settlement trough shape, both surface subsurface, illustrated by examining displacement data obtained using an image-based deformation measurement technique. effects demonstrated, suitability typical...

The paper examines the problem of tunneling beneath buried pipelines and relationship between soil strains pipeline bending behavior. Data are presented from centrifuge tests in which tunnel volume loss was induced sand varying stiffness properties. model were all placed at a Perspex wall strong box such that image-based deformation analyses could be performed. method provided detailed data subsurface pipe displacements illustrated soil-pipe interaction mechanisms occurred during loss,...

In urban areas, engineers often need to assess tunnelling-induced displacements of piled structures and the resulting potential for damage. This paper presents an elastic study tunnel-pile-structure interaction through Winkler-based Two-Stage Analysis Methods (TSAMs), focusing on structural from tunnel excavation beneath frames or simple equivalent beams. Comparison results with 3D finite element analyses shows that TSAM models are able provide a good assessment building displacements....

Tunnel construction is vital for the development of urban infrastructure systems throughout world. An understanding tunnelling-induced displacements needed to evaluate impact tunnel on existing structures. Recent research has provided insight into complex mechanisms that control ground movements in sands; however, combined influence relative depth and soil density not been described. This paper presents data from a series 15 plane-strain centrifuge tests dry sand. The cover-to-diameter...

Urban tunnelling projects pose significant risks to the integrity of nearby structures due ground movements induced by excavation process. Embedded walls are commonly employed as a protective measure mitigate these adverse effects. This paper presents comprehensive numerical investigation into effects embedded on tunnelling-induced displacements, aiming provide insights and recommendations for optimal wall design. The study assesses impact varying length horizontal distance from tunnel soil...

The problem of tunneling effects on existing jointed pipelines is studied using the boundary integral method. Normalized solutions to evaluate maximum bending moments and rotations are presented. They depend tunnel-induced ground settlements at pipeline level, relative soil–pipe stiffness, pipe-joint location joints in relation tunnel centerline. A generally experiences smaller than a continuous one owing joint rotation. indicate that there certain cases where hinged systems result greater...

This paper presents centrifuge model test data that relate to the problem of tunneling beneath driven or jacked end-bearing piles in sand. The consisted a tunnel and two allowed for acquisition subsurface digital images throughout tests. Soil pile displacements were measured using particle image velocimetry close-range photogrammetry techniques. into ground in-flight prior volume loss obtain stress profiles representative conditions around piles. Patterns calculated soil strains are...

Tunnelling under the foundations of structures is becoming more common because lack available space for infrastructure, both above and below ground. The interaction between newly constructed tunnels existing piled an important issue. This paper presents results obtained using a computationally efficient analytical approach which aims to estimate effect that constructing new tunnel will have on pile. method uses spherical cavity expansion analysis evaluate end-bearing capacity pile,...

Cavity expansion theory plays an important role in many geotechnical engineering problems, including the cone penetration test (CPT). One of challenges interpreting CPT data is delineation interfaces between soil layers and identification distinct thin layers, a process which relies on in-depth understanding relationship penetrometer readings properties. In this paper, analytical cavity solutions two concentric regions are applied to interpretation data, with specific focus layered effects...

Evaluation of the impact tunnel construction on existing buried structures is an important problem. This paper presents analytical method for estimating effect end-bearing piles located above tunnel. The can be used to estimate safe relative distance between and newly constructed tunnels. Spherical cylindrical cavity expansion/contraction analyses are evaluate pile capacity reduction confining pressure at tip that results from volume loss. Pile then reevaluated based reduced tip. A modified...

Tunneling beneath piled structures may compromise the stability and serviceability of structure. The assessment potential structure damage is a problem being faced by engineers across globe. This paper presents outcomes series geotechnical centrifuge experiments designed to simulate effect excavating tunnel structures. stiffness weight effects are examined independently using aluminum plates varying (equivalent beam approach) addition weights supported piles. Greenfield displacement patterns...

Empirical formulas and closed-form solutions provide, in many cases, good predictions of tunnelling-induced ground movements which, when combined with their computational efficiency, make them valuable for tunnel-structure interaction analyses. For sandy soils, however, there is a shortage available methods that can adequately describe the changes soil deformation patterns occur as result tunnel volume loss, relative density, geometrical parameters. In this paper, two approaches are adopted...

Tunnels are constructed increasingly close to existing buried structures, including pile foundations. This poses serious concerns, especially for tunnels built beneath piles. Current understanding of the global tunnel–soil–pile–building interaction effects is lacking, which leads designs that may be overly conservative or adoption expensive measures protect buildings. paper presents outcomes from 24 geotechnical centrifuge tests aim investigate salient mechanisms govern piled building...

The process of tunneling is associated with ground movements which may lead to stressing nearby existing buried infrastructure, and potentially poses a risk damage. need for an effective evaluation method the potential increases ongoing expansion underground space utilization. This paper presents new approach evaluating interaction between assumed input greenfield displacements pipeline. integrates developments previous research findings establish practical analysis methodology that can be...

Penetration problems are important in many areas of geotechnical engineering, such as the prediction pile capacity and interpretation situ test data. The cone penetration is a proven method for evaluating soil properties, yet relatively little research has been conducted to understand effect layering on penetrometer readings. This paper focuses probe within layered soils investigates effects both resistance deformation. A series centrifuge tests was performed configurations silica sand with...

Tunnel excavation causes ground movements which have the potential to cause damage other buried infrastructure, including pipelines. This note examines tunnel–pipeline interaction problem from context of an elastic-continuum based approach. A theoretical proof is provided shows that there a constraint volume loss equality between greenfield displacement input and resulting deformed pipeline shape. In addition, for assumed Gaussian curve fit displacements, it shown also fits well These two...

The accurate prediction of strength and deformability characteristics rock mass is a challenging issue. In practice, properties are often estimated from available empirical relationships based on the uniaxial compressive (UCS). However, UCS does not always give good indication in situ deformability. aim this paper to present methodology predict jointed using UDEC (universal distinct element code). study, modelled as an assemblage deformable blocks that can yield intact material and/or slide...

In this paper, the influence of foundation configuration (raft or separate footings) on tunnel–soil–framed building interaction is investigated using geotechnical centrifuge testing. Tunnelling-induced soil movements and deformation fields, framed displacements structure shear distortions (with associated modification factors) are illustrated. Framed stiffness footing bearing capacity also evaluated experimentally. Results show that plays an important role in determining ground response to...

SUMMARY An analytical solution of cavity expansion in two different concentric regions soil is developed and investigated this paper. The embedded within a with finite radial dimension surrounded by second soil, which extends to infinity. Large‐strain quasi‐static both spherical cylindrical cavities elastic‐plastic soils considered. A non‐associated Mohr–Coulomb yield criterion used for soils. Closed‐form solutions are derived, provide the stress strain fields during from an initial final...