Brian Sheil

University of Cambridge | Cam

The simulation of additional soil overburden pressure through the use of a surcharge system is a technique commonly adopted in laboratory testing of pipe–soil interaction. This paper examines the influence of surcharge boundary conditions and pressure level on the axial sliding behaviour of a trenched pipeline surrounded by sand backfill. A novel t...

The behaviour of piles subjected to lateral loads has been explored by a number of investigators over the past five decades. However, the vast majority of the previous literature has ignored the potential influence of additional torsional effects due to horizontal eccentricities of the applied lateral loads. In this paper, an upper bound mechanism...

The settlement behaviour of vertically loaded pile groups has been the subject of an extensive body of research over the past two decades. In particular, this work has identified the over-conservatism associated with predictions of pile interaction derived from elastic theory and the corresponding amplification of group settlement relative to singl...

This paper describes a full-scale laboratory study of the axial sliding behaviour of a trenched pipeline surrounded by sand backfill. Cyclic axial displacements are applied to a heavy pipe buried in a narrow trench (less than three pipe diameters wide), using various backfill cover depths and two different soils: dry Hostun sand and a damp, silty s...

Urban tunnelling projects pose significant risks to the integrity of nearby structures due to ground movements induced by the excavation process. Embedded walls are commonly employed as a protective measure to mitigate these adverse effects. This paper presents a comprehensive numerical investigation into the effects of embedded walls on tunnelling...

In long pipe-jacking drives used for installing utility pipelines, field experience has shown that transient peaks in skin friction arise upon recommencement of jacking after stoppages; these forces are often very large and difficult to predict, presenting a significant risk for contractors. In this paper, the problem is replicated in the laborator...

Fibrous plaster (FP) is a composite material that has been used for suspended decorative ceilings in historical buildings since the late 19th century. Such ceilings are susceptible to failures, particularly in hard-to-access structural hangers (‘wads’). Due to a limited understanding of structural behaviour of FP ceilings, maintenance and reconstru...

The American Petroleum Institute (API) filter press test has been used for decades in the construction industry as part of the quality control regime for bentonite-based excavation support fluids. The industry has carried over the use of this test to polymer fluids despite the lack of published evidence of its suitability for these fluids and the v...

Management of ageing masonry arch bridges entails periodic site inspections to identify signs of potential structural degradation. Previous research has focused on detecting surface cracks from images. This paper develops an alternative approach where cracks are identified from point clouds via geometric distortions. An image-based anomaly detectio...

Accurate three‐dimensional (3D) reconstruction of granular grains from x‐ray micro‐computed tomography (µCT) images is a long‐standing challenge, particularly for dense soil samples. This study develops a machine learning (ML) enhanced approach to automatically reconstruct granular grains from µCT images. The novel academic contributions of this pa...

Fibrous plaster (FP) ceilings, prevalent in late 19th- and early 20th-century UK theatres, are suspended using ‘wads’. Wads are hangers made of Plaster of Paris, reinforced with twisted woven jute fabric. Several recent collapses in historic fibrous plaster ceilings have been attributed to tensile failures in wads. To understand the failure mechani...

Total jacking force capacity is a key design consideration when constructing pipelines using the pipe-jacking (microtunnelling) technique. The total jacking force must match the force at the tunnel boring machine face plus the frictional force between the pipeline and the surrounding ground. In this paper, 15 historical pipe-jacking drives, constru...

This paper describes the design, development, calibration and validation of a novel soil-structure contact stress sensor. The new sensor design combines a novel operating principle, fibre Bragg grating (FBG) strain sensing and data-driven mapping techniques to create a multi-axis contact stress sensor that is both economical and suitably robust for...

Cavity expansion is a canonical problem in geotechnics, which can be described by partial differential equations (PDEs) and ordinary differential equations (ODEs). This study explores the potential of using a new solver, a physics-informed neural network (PINN), to calculate the stress field in an expanded cavity in the elastic and elasto-plastic r...

This paper proposes a practical approach for data-efficient metamodeling and real-time modeling of laterally loaded monopiles using physics-informed multi-fidelity data fusion. The proposed approach fuses information from 1D beam-column model analysis, 3D finite element analysis and field measurements (in order of increasing fidelity) for enhanced...

The static stiffness of suction caisson foundations is an important engineering factor for offshore wind foundation design. However, existing simplified design models are mainly developed for non-layered soil conditions, and their accuracy for layered soil conditions is uncertain. This creates a challenge for designing these foundations in offshore...

Fibrous plaster (FP) ceilings were commonly used in historic buildings throughout the UK during the 19th and 20th centuries. These ceilings are typically supported by hanger elements called wads, which are made of woven jute fabric embedded in plaster of Paris (POP). Recent collapses of several FP ceilings have raised concerns on our ability to det...

This paper investigates the role of basement depth on the response of framed buildings to tunnel construction in sandy soil using finite element modelling. Six frames are considered to explore the influences of tunnel cover depth, building width, eccentricity, and the number of storeys on the role of basement depth. The numerical models adopt the h...

Analytical and numerical techniques are widely used to analyze and interpret soil consolidation problems. An important limitation is the requirement for significant geotechnical knowledge and expertise to derive “true” solutions. This study proposes an alternative: a universal function approximator regularized with known physical principles. The pr...

It is highly challenging to comprehensively measure the deformations of large-scale tunnel structures because of the numerous individual segments of tunnel linings. Laser scanning and 3D deep learning (DL) can provide abundant geometric data and the ability to interpret such data automatically. To fill the gap in applying 3D DL to the segment-wise...

Transformer architecture based on the attention mechanism achieves impressive results in natural language processing (NLP) tasks. This paper transfers the successful experience to a 3D point cloud segmentation task. Inspired by newly proposed 3D Transformer neural networks, this paper introduces a new Transformer-based module, which is called Local...

This paper assesses the effectiveness of different unsupervised Bayesian changepoint detection (BCPD) methods for identifying soil layers, using data from cone penetration tests (CPT). It compares four types of BCPD methods: a previously utilised offline univariate method for detecting clay layers through undrained shear strength data, a newly deve...

Point clouds provide a novel and effective alternative to understanding the structural behaviours of segmental tunnel linings. 3D deep learning (DL) has emerged as a promising technology capable of automatically deriving point-wise semantic and instance labels from point clouds. The utilisation of 3D DL in segment segmentation of tunnel point cloud...

Digital image correlation (DIC) and particle image velocity (PIV) are highly effective non-contact methods to accurately measure full-field deformations in transparent soil model testing (TSMT). The nature of transparent soils combined with the rapid development of three-dimensional (3D) DIC/PIV techniques means that the acquisition of the full int...

Rigorous modeling of the stress-induced anisotropy of soils with different stress histories and loading conditions typically requires advanced constitutive models. However, calibration of state-of-the-art constitutive models can be expensive due to a large number of parameters and can encounter convergence issues when implemented in finite element...

This paper presents a new approach for measuring large deformations in geotechnical experiments employing digital image correlation (DIC) or particle image velocity (PIV) techniques. The proposed method is based on the Eulerian analysis scheme, allowing for the application of multicore central processing unit (CPU)-based parallel computing to exped...

Accurate prediction of soil settlements induced by open caisson construction in sand is essential for safe and reliable delivery of critical underground urban infrastructure. This paper presents a novel prescriptive design approach using a neural network (NN) constrained by empirical relationships, referred to as an 'empiricism-constrained neural n...

The increase in global population and urbanization is presenting significant challenges to society: space is becoming increasingly scarce, demand is exceeding capacity for deteriorating infrastructure, transportation is fraught with congestion, and environmental impacts are accelerating. Underground space, and particularly tunnels, has a key role t...

There is a critical need for a global monitoring capability for Tailings Storage Facilities (TSFs), to help protect the surrounding communities and the environment. Satellite Synthetic Aperture Radar Interferometry (InSAR) shows much promise towards this ambition. However, extracting meaningful information and interpreting the deformation patterns...

Pile driveability predictions require information on the pile geometry, impact hammer and the soil resistance to driving (SRD). Current methods to predict SRD are based on databases of long slender piles and have been shown to provide poor predictions when applied to geometries outside of their original calibration spaces. New, robust and adaptable...

Gaussian Process (GP) regression is a flexible, non-parametric Bayesian approach towards regression problems that has seen increasing adoption for machine-learning (ML) applications. Despite its recent popularity within the ML community, GP regression has a long history in geostatistics, where it is better known as kriging and is commonly used for...

Masonry bridges form an important component of the transport infrastructure in the UK and Europe. Structural issues in these bridges are often identified by the presence of visual surface defects, such as cracks. To automate this process, recent research efforts have focused on identifying defects from images, neglecting the potential information t...

Fibrous plaster (FP) is a natural fabric-reinforced composite material. It has been widely used to produce decorative suspended ceilings in high-profile historical buildings in the UK since the late 19th century. The constituent materials of FP are plaster of Paris (POP) and woven jute fabrics. Despite its prevalence, FP has been neglected in scien...

This paper describes the monitoring of the construction of a deep underground waste storage bunker for the PROTOS Energy-from-Waste Facility in Chester, UK. A key element of the construction process was a 12 m deep excavation in soft clays and peats which was supported by a complex ‘combi-wall’ cofferdam comprising alternate tube and sheet piles, a...

The development of underground spaces inevitably poses significant risks to nearby infrastructure due to construction-induced ground displacements. While our understanding of tunnel-induced ground movements is now relatively mature, there is a distinct lack of literature on large-diameter open caisson shafts. This paper fills this gap by describing...

Bridge foundations located in a water flow environment commonly experience scour, which can lead to significant drops in the soil elevation immediately surrounding the foundation. This has significant ramifications for lateral bearing capacity as well as the integrity of the supported superstructure. While pile groups are one of the most foundation...

Deep, large-diameter caisson shafts are a popular means of constructing underground storage and attenuation tanks and pumping stations for the water and wastewater industry. One of the key design concerns for these structures is resistance to flotation during periods when the tanks are only partially filled or empty. In this paper, two-dimensional...

Bridge foundations located in a water flow environment commonly experience scour, which can lead to significant drops in the soil elevation immediately surrounding the foundation. This has significant ramifications for lateral bearing capacity as well as the integrity of the supported superstructure. While pile groups are one of the most foundation...

Soil strata delineation is a fundamental step for any geotechnical engineering design. The dynamic penetration test (DPT) is a fast, low cost in-situ test that is commonly used to locate boundaries between strata of differing density and driving resistance. However, DPT data are often noisy and typically require time-consuming, manual interpretatio...

Identifying governing equations from data and solving them to acquire spatio-temporal responses is desirable, yet highly challenging, for many practical problems. Data-driven modelling has shown significant potential to influence knowledge discovery in complex geotechnical processes. To demonstrate feasibility, in this study a physics-informed data...

This paper describes direct shear testing of a range of sand-bentonite slurry mixes, identified as a gap in the literature. In the absence of a concrete interface, there was an apparent transition zone from sand-governed strength (bentonite content ≤30%) to clay-governed strength (bentonite content ≥80%), which was linked to the sample void ratio....

Masonry arch bridges constitute the majority of the European bridge stock and feature a wide range of geometric characteristics. Due to a general lack of construction drawings, their geometry is difficult to parameterize. Laser scanning devices are commonly used to capture bridge geometry. However, this requires time-consuming segmentation of point...

In this paper, ground deformation measurements from synthetic aperture radar interferometry (InSAR) and ground-based prism monitoring are compared to finite-element (FE) simulation results for a recent tailings dam collapse. The InSAR monitoring demonstrated the complex spatial and temporal variability of the tailings dam deformation that is not ca...

In long pipe-jacking drives used for installing utility pipelines, maximum jacking load requirements are usually governed by skin friction at the pipe-soil interface. In addition, field experience has shown that transient peaks in skin friction arise upon recommencement of jacking after stoppages; these stoppage durations can be short (due to the a...

Masonry arch bridges constitute the majority of the European bridge stock. Most of these bridges were constructed in the 19th century and feature a wide range of geometric characteristics. Since construction drawings rarely exist, the first step in the assessment of these bridges is the characterisation of their in-situ geometry, which may involve...

Understanding soil-pipe interaction during cyclic axial displacement is essential for the design and evaluation of buried pipeline systems. This study introduces an efficient and practical numerical approach using beam-spring-interface elements to simulate soil-pipe interaction behaviour. Numerical predictions of the evolution of shear and normal s...

This study investigated the effect of helical pile installation in undrained softening clay using a coupled Eulerian-Lagrangian (CEL) finite element modelling approach. A previously published strain softening soil constitutive model was used to evaluate soil disturbance. The influence of two key strain softening parameters was considered to assess...

Jacking forces which exceed expectations constitute a risk for tunnelling contractors. One scenario in which high forces may arise is when jacking of lubricated pipes is temporarily halted, which was considered by Li et al. using a programme of direct shear testing. While recognising the importance of the topic to the profession, the purpose of thi...

In this paper, ground deformation measurements from Synthetic Aperture Radar Interferometry (InSAR) and ground-based prism monitoring are compared to Finite Element (FE) simulation results for a recent tailings dam collapse. The InSAR monitoring demonstrates the complex spatial and temporal variability of the tailings dam deformation that is not ca...

The cavity expansion approach has been a popular tool to interpret a wide range of geotechnical problems over the last several decades. Most previous research focused on the expansion of cylindrical and/or spherical cavities, whereas nonstandard cavities have received much less attention. To address this shortcoming, this paper presents a general t...

There is considerable potential for data‐driven modelling to describe path‐dependent soil response. However, the complexity of soil behaviour imposes significant challenges on the training efficiency and the ability to generalise. This study proposes a novel physics‐constrained hierarchical (PCH) training strategy to deal with existing challenges i...

The cavity expansion approach has been a popular tool to interpret a wide range of geotechnical problems over the last several decades. Most previous research focused on the expansion of cylindrical and/or spherical cavities whereas ‘non-standard’ cavities have received much less attention. To address this shortcoming, this paper presents a general...

In this paper, the lateral limiting pressure offered by the deep ‘flow-around’ soil failure mechanism for perimeter (ring) pile groups in undrained soil is explored using two−dimensional finite element modelling. A parametric study investigates the role of group configuration, pile−soil adhesion, group size, pile spacing and load direction on group...

Coupled hydromechanical finite element modelling of granular soils, taking into account internal erosion, is computationally prohibitive. Alternative data-driven approaches require large datasets for training and often provide poor generalization ability. To overcome these issues, this study proposes a ‘physics-informed multi-fidelity residual neur...

Open caissons are an increasingly common means of constructing underground storage and attenuation tanks as well as launch and reception shafts for tunnel-boring machines. The caisson walls typically feature a tapered base, referred to as the ‘cutting face’, to aid the sinking process by reducing the vertical soil reaction. The primary aim of this...

In this paper, the lateral limiting pressure on rectangular pile groups in undrained soil is explored using two-dimensional finite-element (FE) modelling. The primary aim of the study is to assess the influence of pile group shape effects on the soil limiting pressure offered by the deep ‘flow-around’ failure mechanism, and associated soil failure...

The use of supporting fluids to stabilise excavations is a common technique adopted in the construction industry. Rapid detection of incipient collapse for deep excavations and timely decision making are crucial to ensure safety during construction. This paper explores a hybrid framework for forecasting the collapse of fluid−supported circular exca...

This paper presents a numerical study of 3x3 pile groups embedded in clay under vertical and inclined eccentric loads. Simplified modelling, based on elastic beams embedded in a soil continuum, is used to explore the soil-pile-cap response. This simple model allows rigorous treatment of the 3D foundation geometry and local soil plasticity, demonstr...

An accurate estimation of the jacking forces likely to be experienced during microtunnelling is a key design concern for the design of pipe segments, the location of intermediate jacking stations and the efficacy of the pipe jacking project itself. This paper presents a Bayesian updating approach for the prediction of jacking forces during microtun...

This paper describes a finite element study of the uplift behaviour of a plane strain pipe segment embedded in modified Cam clay soil. The primary aim of this study is to explore the role of rate effects on pipe uplift capacity and the transition between drained and undrained behaviour using coupled-consolidation analyses. The velocities considered...

Open caisson shafts are a widely adopted solution for a range of geotechnical applications. An external ‘cutting shoe’ is a common construction feature used to reduce the soil frictional resistance acting on the caisson during sinking. This forms an annular void encircling the caisson which is filled with a support fluid to maintain excavation stab...

Large-diameter open caissons are an increasingly common means of constructing underground storage and attenuation tanks, as well as launch and reception shafts for tunnel-boring machines. A ‘cutting face’ at the base of the caisson wall, resembling an inclined ring footing, is typically used to aid the sinking phase. This paper describes a suite of...

‘Clogging’ is a common issue encountered during tunnelling in clayey soils which can impede tunnel excavation, cause unplanned downtimes and lead to significant additional project costs. Clogging can result in a drastic reduction in performance due to reduced jacking speeds and the time needed for cleaning if it cannot be fully mitigated. The data...