Marcos Arroyo

Universitat Politècnica de Catalunya | UPC · Department of Civil and Environmental Engineering (DECA)

In situ free fall penetration tests (FFP) are performed for cable routes development due to their cost and efficient way to geotechnical characterize near-surface marine sediments. FFP readings differs from quasi-static observations due the higher impact velocity and nonlinear penetration rate of the cone probe. Therefore, application of FFP observ...

Sampling disturbance is a perennial problem of geotechnical site investigation. The structure of soft soils is particularly fragile and prone to disturbance during sampling. The extent by which different sampling procedures modify soil structure has been generally assessed on an empirical basis, observing the outcomes of tests performed on specimen...

Driven, and recently vibrated piles, are routinely employed offshore. Since the 1970s, much study has been conducted on the behaviour of the soil-pile interface, and small-scale studies have demonstrated that if grout could be applied to the interface between the pile and the marine sediment, the friction on driven (and vibrated) piles may be great...

An attractive approach to reduce the carbon footprint for ground improvement application is to replace Portland cement-based binders by non-cementitious binders for instance by geopolymers based on metakaolin in deep soil mixing applications or by colloidal silica and acrylates in permeation based applications. Safe design requires a good understan...

In situ dynamic cone penetration tests (CPTu) are performed to efficiently characterize nearsurface marine sediments. Dynamic data require a strain-rate correction according to strain-rate model and law due to the nonlinear penetration rate of the cone probe insertion. This requires paired (i.e., closely located in space and time) quasi-static and...

In this paper, cone penetration testing is simulated in potentially liquefiable soils using the Geotechnical Particle Finite Element method, specially designed for the analysis of penetration problems in geomechanics. The material response is modelled with CASM, a critical state, state-parameter dependent model. The paper reports a parametric analy...

A contact model able to capture creep of crushable sands within a discrete element method (DEM) framework is presented. Time dependency is established through stress-corrosion induced grain fracture. This is grafted onto a pre-existing particle-splitting model developed to simulate rough-crushable sands. The model is calibrated for Fontainebleau sa...

The state parameter is a key descriptor to understand the potential soil vulnerability to liquefaction. State parameter is often inverted from CPTu readings, but inversion methods have been developed only for fully drained and fully undrained conditions. Therefore, the results are sensitive to partial drainage upon penetration. Cone penetration tes...

Bender element testing of geomaterials involves inducing a shear wave at one end of a sample (the input signal) and reading its arrival at the other end (the output signal). As compared to resonant columns, bender elements are cheaper, flexible to install, easier to use and yield similar results. However, the wave propagation induced by bender elem...

Node-based smoothed finite element (NS-FEM) formulations for the coupled hydro-mechanical problem are now becoming popular in soil mechanics, but there has been limited comparative study of their performance. In this work, a node-based formulation is developed for the coupled hydro-mechanical problem (u-pw formulation) using low-order, equal-order...

This paper presents a new interpretation procedure to estimate the initial state parameter from cone penetration testing (CPTu) in undrained conditions based on the results from a comprehensive set of numerical simulations of CPTu in low permeability liquefiable soil. CPTu simulations are performed using the Particle Finite Element method, whereas...

Cone Penetration Test (CPTu) and flat Dilatometer Test (DMT) are widely employed in-situ tests for ground unit profiling in terms of Soil Behavior Type Index IC and Material Index ID. CPTu provides a nearly continuous data profile with respect to DMT, making it more appealing for soil unit identification, leaving DMT data for qualitative comparison...

This paper presents a new interpretation procedure to estimate the initial state parameter from cone penetration testing (CPTu) in undrained conditions based on the results from a comprehensive set of numerical simulations of CPTu in low permeability liquefiable soil. CPTu simulations are performed using the Particle Finite Element method, whereas...

Grouting is a technique used to improve the engineering properties of soils and rocks. Grouting techniques are classified under different criteria: injection method used, type of grout material injected, typical application, and the sequence of construction. The best-known criterion is the mode of entrance or admission of grout into the soil or roc...

Dynamic Cone Penetration Tests (CPTu) profile offshore sediments by impact penetration. To exploit their results in full the measured data is converted to obtain a quasi-static equivalent profile. Dynamic CPTu conversion requires calibrated correction models. Calibration is currently done by using paired (i.e., very close) quasi-static and dynamic...

The presence of potentially liquefiable deposits in tailing dams represents a serious hazard, as is now increasingly clear that liquefaction triggering may occur in unanticipated ways. For legacy dams in which this hazard is already present, intervention alternatives are sought to mitigate the associated risks of liquefaction failure. One interesti...

Arguably, critical state soil mechanics (CSSM) is now the preeminent methodology for understanding static liquefaction of mine tailings, having been used in the mining industry by the expert panels retained to investigate recent TSF failures. One of the key ingredients of the CSSM framework is the assessment of a critical state line, which separate...

This paper illustrates how pressuremeter testing may add value to geotechnical characterization of tailing storage facilities (TSF). This is done with reference to results obtained in a campaign on jarosa, a lime-stabilized filtered jarosite residue that results from electrolytic zinc production. These residues are often stabilized chemically to mi...

Failures due to static liquefaction have been too frequent in tailings dams. Stress-deformation numerical analyses based on critical state theory are able to reproduce those failures and may be used to gain insight into the different factors involved. One factor that is sometimes believed to play a role in liquefaction triggering is tailings creep,...

Cone Penetration Test (CPTu) and flat Dilatometer Test (DMT) are widely employed in-situ tests for ground unit profiling in terms of Soil Behavior Type Index IC and Material Index ID. CPTu provides a nearly continuous data profile with respect to DMT, making it more appealing for soil unit identification, leaving DMT data for qualitative comparison...

In this work, we present a novel explicit time-integration algorithm for the coupled hydromechanical soil mechanics problems in a pseudo-static regime. After introducing the finite element discretization, the semi-discrete ordinary system of equations is integrated explicitly in time with the Runge-Kutta method. It is noted that this formulation is...

We present a modified Rowe cell for the estimation of shear moduli of geomaterials. It uses transmitter and receiver bender elements on the same side of the sample (echo measurement), allows for the installation of multiple receivers, and offers stiff and flexible enclosures on its reflecting end.

In permeation grouting, a fluid carrying a binder enters the soil voids under low pressure. The binder sets and cures in the ground, thereby creating a treated soil with larger strength and stiffness and reduced permeability. Permeation grouting is one of the oldest technologies in ground improvement, but also one with a fast pace of technological...

Accurate estimates of soil unit weight are fundamental for correctly post process CPTu data and making use of Soil Behavior Type-based classification systems. Soil-specific and global regressions have been proposed for this purpose. However, soil-specific correlation might pose a problem of pertinence when applied at new sites. On the other hand, g...

CPTu-based soil profiling has become a key component in the geotechnical design process. However, this is an interpretative process, affected by the inherent variability of soil properties, measurement noise and subjective heuristics. These are difficult to communicate to other interpreters or, even for the same interpreter, to transfer across prof...

Accurate estimates of soil unit weight are fundamental for correctly post process CPTu data and making use of Soil Behavior Type-based classification systems. Soil-specific and global regressions have been proposed for this purpose. However, soil-specific correlation might pose a problem of pertinence when applied at new sites. On the other hand, g...

CPTu-based soil profiling has become a key component in the geotechnical design process. However, this is an interpretative process, affected by the inherent variability of soil properties, measurement noise and subjective heuristics. These are difficult to communicate to other interpreters or, even for the same interpreter, to transfer across prof...

Static liquefaction of soils that have a brittle undrained response (hydraulic fills, mine tailings or sensitive clays) may lead to sudden failures of large consequence. Given the importance of undrained failure, obtaining precise estimates of peak and residual yield strength is important. The CPTu plays a major role in the geotechnical characteriz...

Computational Analyses of Dam I Failure at the Corrego de Feijao Mine in Brumadinho. Final Report for VALE SA, August 2021

Penetration depth of Spudcan foundations for offshore mobile Jack-up rigs is typically predicted by considering a wished-in-place foundation at different depths and following traditional bearing capacity approaches. However, the large penetration depths involved, stress redistributions and the flow of the material around the spudcan are some exampl...

Both static and dynamic penetration tests are widely used to conduct soil investigation practice. Particle crushability has been known to greatly affect the responses of penetration tests. On the other hand, the physical property of granular materials – surface roughness – exhibits considerable influence on crushability. The virtual calibration cha...

An attractive approach to reduce the carbon footprint of deep soil mixing (DSM) is to replace Portland cement-based binders by geopolymers based on metakaolin. Safe design requires a good understanding of the mechanical and hydraulic properties of the improved ground but very little is known about metakaolin-soil mixtures. For instance, shrinkage d...

As society moves towards decarbonisation it is important to assess the hydro-mechanical behaviour of binders that could offer a low-carbon alternative to Portland cement in ground improvement technologies. This work considers two such alterna-tives: one still largely unexplored (metakaolin-based geopolymers) and a better known one (colloidal silica...

Disturbance of specimens recovered by tube sampling from boreholes is an enduring relevant problem in geotechnical engineering. Practice has evolved slowly in this area, partly because the main research method applied, involving comparative field sampling and testing, remains strictly empirical. Theoretical approaches based on the strain path metho...

RESUMEN: En Enero de 2019 en Brumadinho (Brasil) una presa de relaves mineros de gran tamaño colapsó en su totalidad de forma brusca, causando la muerte a 270 personas y una gran conmoción en la minería mundial. La rotura fue capturada en video por una cámara que permitió identificar rápidamente el modo de rotura como uno de licuación. La cuestión...

The impact of the use of sand treated with Colloidal Silica (CS) on a model 80 m high-earthfill dam was assessed through numerical modelling. The hydro-mechanical properties of the CS-treated soil were taken from a previous laboratory study. Different strategies of treatment placement were studied, with increasing volumetric fractions of the dam be...

The possibilities of the particle finite element method (PFEM) for modeling geotechnical problems are increasingly evident. PFEM is a numerical approach to solve large displacement and large strain continuum problems that are beyond the capabilities of classical finite element method (FEM). In PFEM, the computational domain is reconfigured for opti...

A recently proposed DEM model for materials with rough crushable grains (Zhang et al. 2021; Ciantia et al. 2015; Otsubo et al. 2017) is here employed to examine the effect of contact roughness on the critical state line, a property of granular materials which is a) fundamental for the evaluation of liquefaction risk and liquefied responses and b) e...

Contact rolling resistance is the most widely used method to incorporate particle shape effects in the discrete element method (DEM). The main reason for this is that such approach allows for using spherical particles hence offering substantial computational benefits compared to non-spherical DEM models. This paper shows how rolling resistance para...

Recent analyses have suggested that creep or rate effects may be present in some tailings and can play a role in triggering liquefaction failure. However, the role of creep in liquefaction triggering analysis of tailing dams is complicated by the effects of drainage and/or consolidation. To gain some understanding of this aspect, we investigate liq...

Chalk covers areas of the UK and is widespread under the North and Baltic Seas where OWT are currently being installed and where future offshore expansion will be sited. Large piles are often driven in chalk to support OWT and other onshore infrastructure. The installation of pile foundations causes the intact rock surrounding the pile to crush and...

A singular advantage of discrete element models (DEM) is their potential to incorporate grain scale information in the formulation of element behaviour and/or element interactions. This feature may lead to greatly simplified model calibration, bypassing the perennial soil mechanics problem of obtaining and testing representative samples. Within thi...

The use of stress-deformation analyses to evaluate the characteristics of possible static liquefaction events is rapidly becoming the norm for tailings dams exposed to such risk. Ideally, those analyses should be based on constitutive models that incorporate the fundamental mechanics of the problem, that are able to perform robustly in commercial n...

The cone penetration test (CPTu) is one of the most widely used geotechnical site investigation method and research on the interpretation of the test began once the instrument became available. Traditionally, permeability has been obtained using dissipation tests, which are frequently slow and only link permeability through compressibility measurem...

The role of in situ tests in numerical analyses of deep excavations is investigated. The construction of a metro station in Barcelona required a deep excavation in a densely built urban area. Geological conditions were complex and challenging, involving soft alluvial materials below groundwater level. A comprehensive instrumentation system allowed...

Gabion-type support is a favoured option to restrain bulking in pillar walls of mine footprint tunnels. It uses closely spaced short reinforcements in tunnel walls (typically fully grouted rebar) in combination with surface support (rock fragment retention systems such as shotcrete, weld wire mesh, straps, etc.). The system is installed while the r...

The paper presents a comprehensive set of simulations of the cone penetration test with pore pressure measurements (CPTu test) in brittle, potentially liquefiable, soils using advanced numerical techniques. The large displacements and large deformations involved in the cone penetration problem are tackled using the Particle Finite Element Method, e...

En la exploración costa afuera con fines geotécnicos, la caracterización morfológica del fondo marino juega un papel importante en la definición de proyectos de implantación de estructuras mar adentro. Dentro de las geoformas que pueden estar presente, en ambientes marinos, se encuentran unas depresiones o máculas (pockmarks en inglés), que resulta...

The Standard Penetration Test (SPT) is the most popular example of dynamic probing, a large category of soil testing techniques. Understanding and interpretation of these tests is hampered by the difficulties of reproducing them under controlled laboratory conditions. The virtual calibration chamber technique, based on the Discrete Element Method (...

The stability of methane hydrate depends on not only temperature and pressure but also the salinity of the environment where the methane hydrate exists. The variation in the stability of methane hydrate due to the change in salinity induces mechanical response in micro scale of the methane hydrate-bearing sediments (MHBS). However, it is really hea...

Sand roughness is now accessible to measurement. Incorporating this parameter into sand models using the discrete element method (DEM) is known to improve bulk small strain response. In this work we explore the effect on problems where particle crushing takes place. A well-established DEM particle crushing model and a rough Hertzian contact model a...

Models that introduce rolling resistance at the contact are widely employed in simulations using the discrete element method (DEM) to indirectly represent particle shape effects. This approach offers substantial computational benefits at the price of increased calibration complexity. This work proposes a method to simplify calibration of rolling re...

This work presents a robust and mesh-independent implementation of an elasto-plastic constitutive model at large strains, appropriate for structured soils, into a Particle Finite Element code specially developed for geotechnical simulations. The constitutive response of structured soils is characterized by softening and, thus, leading to strain loc...

The Standard Penetration Test (SPT) is the most widely used method for dynamic testing of soils. The test is simple and robust but difficult to control and not fully standardized. As a result, experimental results typically show large variations and poor repeatability. To mitigate that correction factors such as energy normalization and rod length...

Particle shape has a strong effect on the mechanical response of coarse soils. This has been usually observed examining specimen-scale or engineering-scale responses, which are the sum of many microscale interactions. In this work we observe the effects of particle shape directly at the microscale level. X-ray tomography (μ-CT) of two sand specimen...

The SW Iberian margin is recognized to be a tectonically active area with major canyons and profuse evidence of mass wasting, representing a plausible region for tsunami generation due to submarine earthquake-triggered landslides. For this reason, submarine landslide susceptibility mapping becomes a major concern for regional mitigation risk strate...

A site investigation campaign was carried out to assess jack up leg penetration in several sites of an offshore area in the Northeastern coast of South America. The investigation identified a thick layer of overconsolidated, medium to hard clay, with a thickness between 30 to 40 m, in which the undrained shear strength showed strong dependency on t...

Borehole tube sampling is a key process of geotechnical engineering. The paper presents numerical analyses of smooth tube sampling in clay using the Particle Finite Element Method (PFEM). The soil is described by a conventional elasto-plastic constitutive model (Tresca plasticity and a quasi-incompressible elastic law). The sampler is advanced by s...

The self-boring pressuremeter (SBP) test was designed to measure in situ engineering properties of the ground with a relatively small amount of disturbance. The properties that may be inferred from the test depend on the mechanical model used for its interpretation and on the significance given to other previously available information. In this pap...

The SW Iberian continental margin is well recognized as a tectonically active area, where major canyons and mass wasting events are both present. Earthquake triggered submarine landslides may cause tsunami and result in catastrophic damage to bordering coastal areas. In this setting, submarine landslide susceptibility mapping represents a major ste...

Geotechnical soil profiling of a site is a key step in geotechnical design. Cone Penetration Test (i.e. CPTu) has become a widely used in-situ method for soil classification based on characteristic responses to the cone. Nevertheless, CPTu-based profile delineations inevitably require engineering interpretation, as the CPTu record is affected both...