bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantifying Statistical Uncertainty in Site Investigation
Authors: Ching Jianye  , Wu Shih-Hsuan  , Phoon Kok-Kwang
Published: February 2025

Due to limited information in site investigation, it is not possible to obtain the actual values for the mean, standard deviation, and scale of fluctuation of a soil property of interest. The deviation between the estimated values and actual values is called the statistical uncertainty. There are two schools of thoughts on how to model the statistical uncertainty: frequentist thought and Bayesian thought. The purpose of this paper is to discuss their philosophical difference, to show how to quantify the statistical uncertainty based on these two distinct schools of thoughts, and to compare their performances. For the frequentist school of thought, the confidence interval will be used to quantify the statistical uncertainty, whereas the posterior probability distribution will be used for the Bayesian school of thought. Examples will be presented to compare the performances of these two schools of thoughts in terms of their consistencies. The results show that in general the Bayesian school of thought performs better in terms of consistency. In particular, the Markov chain Monte Carlo method is recommended when the information amount is very limited.
Introducing a Dutch Guideline on Using the Observational Method
Authors: Bles Thomas  , Stoevelaar Ruud  , de Jong Erwin
Published: February 2025

In the Netherlands research has been performed on the Observational Method, aiming at a wider use of the method in the design of underground and infrastructural construction works. This paper summarizes the guideline that was output of the research, providing a clear definition, an overview of obstacles and pre-conditions, practical recommendations on how to make a safe design while using the principles of Observational Method within the context of the Eurocode 7 and practical recommendations on how to organize the method during construction.
About the pore pressure influence in the failure processes and localization analysis of partially saturated soil based on a gradient poroplastic theory
Authors: Mroginski Javier L.  , Etse Guillermo
Published: February 2025

The strain localization problem of frictional cohesive porous materials like partially saturated soils is strongly related to water saturation degree and the softening mechanical behavior. In this situation a pathological dependences of the FE numerical solution is observed with respect to the size and orientation of the considered spatial discretization. Therefore, to realistically and objectively describe the dramatic change from diffuse to localized failure mode or from ductile to brittle ones, accurate constitutive theories and numerical approaches are required. In this article, a non-local gradient poroplastic model proposed by (Mroginski and Etse, Int. J. Solids Struct., 51: 1834–1846, (2014)) for partial saturated media based on thermodynamic concepts is considered. The non-local softening formulation of the proposed constitutive theory incorporates the dependence of the gradient characteristic length on both the governing stress and hydraulic conditions to realistically predict the size of the maximum energy dissipation zone. The material model employed in this work to describe the plastic evolution of porous media is the Modified Cam Clay, which is widely used in saturated and partially saturated soil mechanics. To evaluate the dependence of the transition point between ductile and brittle failure regime in terms of the hydraulic and stress conditions, the localization indicator for discontinuous bifurcation is formulated for both drained and undrained conditions, based on wave propagation criterion. Numerical results are presented and discussed to demonstrate the capabilities of the proposed theory to simulate failure behaviour of saturated media.
Modelación numérica de flujos de detritos basado en la teoría de aguas someras
Authors: Trujillo-Vela Mario Germán  , Escobar-Vargas Jorge Alberto  , Ramos Cañón Alfonso Mariano
Published: February 2025

Con base en la teoría de aguas someras, este trabajo presenta la modelación numérica de flujos de detritos. Así se tiene tres ecuaciones, una de conservación de masa y dos de momentum. Los términos fuente contienen las fuerzas de los sólidos y el fluido encargados de la disipación de la energía. Para la discretización espacial se utilizó un método de precisión de alto orden llamado método penalizado de multidominios espectrales. Esta técnica se basa en el método de colocación aplicado a múltiples subdominios rectangulares. Para la discretización de los términos temporales se utilizó un método de Runge-Kutta de preservación de estabilidad fuerte. El caso de estudio es una avalancha granular, básicamente una mezcla de sólidos y aire que desciende por un canal rectangular de pendiente variable. Los resultados numéricos se validan con mediciones experimentales dadas por Denlinger y Iverson (2001). Con el fin de obtener resultados robustos se utilizaron dos tipos de condiciones de fronteras (deslizantes y antideslizantes) y dos tipos de aproximaciones para el coeficiente de presión lateral de tierras (uno constante y otro regularizado). Los resultados predicen de forma adecuada el experimento. Las condiciones de frontera deslizante permiten predecir mejor el depósito de material, mientras las antideslizante, permiten predecir mejor la dinámica del flujo. Un coeficiente lateral de tierras regularizado puede presentar oscilaciones a diferencia de un coeficiente lateral de tierras constante.
Comparison of an Equivalent Linear and a Nonlinear Soil Model for the Identification of Soil Dynamic Properties
Authors: Mercado Vicente  , Zeghal Mourad  , El-Sekelly Waleed  , Abdoun Tarek
Published: February 2025

Accurate estimation of soil dynamic properties is necessary in most geotechnical earthquake engineering applications. This paper presents a comparison of the identification of soil parameters using two soil material definitions. The identification technique is geared towards soil deposits subjected to base excitation, and it uses the acceleration records provided by a vertical (downhole) array. The implemented material models include an equivalent linear model based on the Kelvin–Voigt formulation, and a nonlinear model which uses a hyperbolic definition of the shear stress-strain backbone curve of the material. Shear wave velocity (Vs) and damping ratio (β) are estimated based on the material behavior. Capabilities of the identification analyses using both soil models are assessed using a reduced-scale centrifuge test.
Remedial Measures for a Building With Pile Foundations in Subsiding Soil
Authors: Décourt Luciano  , Koshima Akira
Published: February 2025

A comprehensive study sought to determine the causes of settlements of the fill. One hypothesis was the collapse of the deepest fill layer, wich was the worst one, due to infiltration of water. However, whatever the settlement causes could might be, the fact was that the fill was continuously settling and pushing the piles downward due to negative skin friction. The paper presents the adopted solution and the results of settlement measurements carried out for checking the efficiency of the soil improvement using jet grouting.
The Use Of The Expander Body With Full Displacement Piles In Medium Dense To Dense Sandy Soils
Authors: Terceros Herrera Mario A.  , Terceros Arce Mario
Published: February 2025

The Expander Body (EB) technology has been used successfully to increase the pile toe capacity of bored piles in loose to dense soils. An important advantage of the EB system is the ability to monitor the EB expansion process, which provides important information regarding soil strength and soil stiffness. This information, obtained for each installed pile, can be used to determine the actual shape and pile toe area. The expansion pressure can be used to design the pile base capacity.
Estudio comparativo del comportamiento de pilas circulares ante carga lateral
Authors: Sosa Félix  , Martínez Sergio
Published: February 2025

Este artículo incluye la revisión ante carga lateral de una pila circular (1.0 m de diámetro) empotrada en material competente. La instalación de la pila es con perforación previa y colada en sitio. La revisión compara diferentes herramientas de cálculo: Métodos convencionales para determinar curvas P-Y y la utilización de modelos numéricos con base en los métodos de elemento finito y de diferencias finitas. Los modelos numéricos consideran la influencia de la instalación de la pila en la respuesta del sistema suelo-pila. Además, la revisión considera dos estratigrafías típicas de la Ciudad de México: 1) compuesta por capas duras de arena limosa intercaladas con arcilla blanda y 2) intercalaciones de capas de arena limosa densa, arcilla arenosa de consistencia media a dura y arena limosa muy densa [1]. Debido a la rigidez de los suelos superficiales que confinan a la pila, la interfaz suelo-pila permite o no su separación. El comportamiento de los geo-materiales en los modelos numéricos es elasto-plástico con criterio de falla Mohr Coulomb, y para cada estrato de suelo el análisis es drenado o no-drenado en función de la permeabilidad del suelo.
A Critical Comparison of a Foundation on Continuous Flight Auger Piles: Global Safety Factor and Partial Factors Design Approach
Authors: Andrade W.S.  , Danziger B.R.  , Freitas A.C.  , Pacheco M.P.
Published: February 2025

The most recent version of the Brazilian Code for Design and Construction of Foundations, ABNT NBR 6122 [1], allows two alternative approaches for consideration of the safety factor in foundation design: i) global safety factor or allowable stress design (ASD) and ii) partial safety factors or load and resistance factor design (LRFD). This paper compares a foundation design on a recent concluded project on continuous flight auger pile based on both approaches and the results of loading tests. The design pile embedment obtained by the two approaches and by two distinct calculation methods show comparable results, although pile load tests have shown the project design values are slightly over conservative.
Influence of the compaction process in the shear strength of a volcanic soil
Authors: Viveros Livaniel  , Colmenares Julio  , García Juan
Published: February 2025

This study contains experimental results on the influence of the compaction process over the shear strength of a soil derived from volcanic ash. The tested soil comes from the area of Palestina, located in the department of Caldas in the center of Colombia. This research includes the use of both basic and advanced experimental techniques: dynamic and static compaction methods that allow to estimate the impact of the applied compaction energy on the material; and the technique of the filter paper that enables to evaluate the characteristics of water retention in statically compacted samples for different compaction conditions. The experimental results led to observe the behavior of the soil in terms of its density and water content at compaction, also considering the suction characteristics. Different types of soil fabric generated as a result of the nature and magnitude of the compaction energy were found; on the other hand, the variation of some soil properties, such as water retention, shear strength and soil stiffness, was observed. The extended Mohr-Coulomb failure criterion [1] accurately represented the final stress conditions at failure.
Caracteristicas de los Suelos no saturados del tropico humedo peruano
Authors: Carrillo-Gil Arnaldo  , Carrillo-Acevedo Arnaldo
Published: February 2025

Este documento muestra los resultados de un programa experimental llevado a cabo en los suelos tropicales de la planicie amazónica peruana desde hace más de 30 años. Con esta información se ha formado una Base de Datos que ha reunido 1,318 muestras y ensayos que permiten establecer las características de estos suelos no saturados en todas las cuencas que conforman la región tropical del Perú, confirmándose que sus características de resistencia al cortante dependen de factores genéticos, grado de meteorización, ubicación dentro del perfil de suelo y de los procedimientos ejecutados antes y después de realizados los ensayos, resultados que presentan ocurrencias geotécnicas de suelos residuales jóvenes que indican similitud y diferencias substanciales en su comportamiento a esfuerzo y deformación.
Natural Soil Modified with Polymer for use in landfill systems
Authors: Marti Luz  , Codevilla Mauro  , Pique Teresa M.  , Manzanal Diego
Published: February 2025

The purpose of this study is to examine the addition of an anionic polyacrilamide polymer to natural clay and a clay-sand mixture for the possible use in landfill systems. The polymer interacts both with fine soil (clay) and granular soil (sand) generating particles aggregation with a small amount of polymer addition. The polymer reduces the micro porosity and changes the water retention capacity of the soil-polymer mixture. The swelling potential, swelling pressure and compression strength were measured. The results are presented in terms of the variation of the index properties, the effects of the polymer in the potential expansion of the soil samples, the relationship of suction-degree of saturation and unconfined compression strength. The hydraulic and mechanical behaviour of clay-polymer and sand-clay-polymer mixtures present significant changes due to polymer addition.
Swelling Pressure of a Shale against a Stiff Tunnel Support
Authors: Mesri Gholamreza  , Pakbaz Mohammad C.  , Wang Cai
Published: February 2025

The swelling pressure that a shale surface exposed in a tunnel mobilizes against a stiff support is expressed in terms of the undrained expansion of shale mass adjacent to the excavation. The expansion of shale is mainly through the opening of joints and fissures during excavation and before installation of the lining. An analytical method is developed for predicting time-rate of swelling pressure development on a stiff lining in a circular tunnel. Both the concept of mobilized swelling pressure as well as the time dependent development of swelling pressure are examined by means of predictions of swelling pressure for a tunnel in Taylor shale in San Antonio, Texas, and are evaluated using ground pressure measurements around a tunnel in London clay.
Evaluación de Metodologías de Diseño de Sobrecarpetas Basada en Criterios del Cuenco de Deflexiones en la Ciudad de Bogotá
Authors: Gomez Maldonado Orlando Elias  , Murillo Carol Andrea
Published: February 2025

Las sobrecarpetas asfálticas son una alternativa de rehabilitación de pavimentos, que permite restaurar la condición estructural y/o aumentar la capacidad de una estructura existente para soportar un incremento del tráfico. Sin embargo las metodologías de diseño generalmente empleadas en la ciudad de Bogotá dependen de una caracterización subjetiva del estado de la estructura existente. Métodos basados en mediciones no destructivas están disponibles pero la caracterización de la subrasante resulta crucial para obtener espesores adecuados. Usando el FWD (Falling Weight Deflectometer) se tomaron mediciones en 10 tramos de vías locales de la ciudad con una condición regular y mala. Basado en el trabajo experimental se desarrolló un modelo 2D de elementos finitos que fue calibrado para las condiciones de la ciudad. Se aplicaron tres métodos de diseño de sobrecarpeta y con los espesores obtenidos se modelaron los cuencos de deflexión para las estructuras. De los anteriores resultados se calcularon los parámetros geométricos asociados al cuenco de deflexión y se compararon con límites propuestos para la ciudad. Se encontró que la diferencia entre los métodos puede ser hasta del 300%. Se estableció un límite para la utilización de sobrecarpetas en vías locales y se plantearon correlaciones entre el espesor de carpeta requerido y los parámetros del cuenco.
Highlights of numerical analysis for tunnels in soft soils
Authors: Rangel-Nuñez José-Luis  , López-Bautista Fabian  , Ibarra-Razo Enrique
Published: February 2025

In order to analyze the stability of excavations in tunnels built on soft soil, as well as to promote safety and avoid major surface settlements, it is important to take into account in the numeric model used in the analysis,characteristics of strength and deformability of the soil and the supports, but mostly the process of construction of the tunnel itself. Truthfulness and accuracy of such numerical models depend on factors such as: i) adequate characterization of soil and supports using constitutive equations applicable to these materials, ii) the representation of the process of tunnel construction, iii) selection of boundary conditions iv) confidence in and mastery of tunnel software by the user. This work presents results obtained by studying tunnels built in the soft soil deposits of Mexico City where different strategies for modeling the construction process and different constitutive equations were used. Based on these findings, recommendations are made for the numerical analysis of tunnels in soft soils.
Failure Mechanism Associated with Hydrostatic Pressure in Deep Seated Landslides on the Eastern Slopes of the AburrÁ Valley
Authors: Echeverri Ramírez Óscar  , Hoyos Patiño Fabián  , Salvá Ramírez Marisol  , Velásquez Pérez Alejandro
Published: February 2025

Some landslides on high-mountains slopes can be explained as a progressive failure process under particular hydrogeological conditions in which an impermeable soil layer constitutes the seal or the aquiclude of a confined aquifer in the bedrock. The hydrostatic pressure on the bedrock can fracture the upper impermeable layer, triggering a progressive failure process.
Numerical Computation of avalanches of unstable rock masses
Authors: Fanelli Sonia  , Dimnet Eric
Published: February 2025

The paper presents the numerical tool STTAR3D developed for rock-avalanches computations through the results of a real case study. STTAR3D is designed for 3d polyhedral shaped granular material computations by the A-CD2method that is also presented. Pre- and post-processing devices have also been developed in order to facilitate the computation of real case rock-avalanches and to provide accurate data for designing protection devices.
Determinación de curvas de vulnerabilidad de viviendas ante procesos de remoción en masa en la ciudad de Bogotá
Authors: Perico García Nelson  , Ávila Álvarez Guillermo
Published: February 2025

La vulnerabilidad física de viviendas a procesos de remoción en masa se puede estimar mediante el uso de metodologías cualitativas, semicuantitativas y cuantitativas que involucran escalas valorativas, matrices de daño, curvas generales de vulnerabilidad o modelación numérica de cada elemento. En particular, las curvas de vulnerabilidad, fragilidad o daño de viviendas, pueden determinarse a partir de la evaluación del comportamiento de las mismas afectadas por eventos reales. En este artículo se presentan los análisis y resultados que permiten identificar características de vulnerabilidad física para distintos tipos de viviendas que han sido afectadas por deslizamientos registrados en las laderas de Bogotá. Se caracterizó el tipo y magnitud de cada proceso de remoción en masa y el daño físico ocurrido, considerando las diferentes solicitaciones, de tal manera que los resultados permiten contar con información que relaciona las características y magnitud del evento con la tipología de los daños generados en las distintas clases de vivienda, lo cual es un avance significativo para la construcción de las curvas de vulnerabilidad por deslizamientos en entornos urbanos.
V
Authors: Cabas Ashly  , Rodriguez-Marek Adrian  , Montalva Gonzalo A.
Published: February 2025

Ground motion recordings used as input motions at the elastic half-space (EHS) in site response analyses (SRA) are typically selected based on similarities between the shear wave velocity (Vs) of the assumed EHS, and the upper layers of the recording station's geologic profile (among other aspects such as the intensity of the expected ground motion, distance to rupture, type of source, etc.). Often, rather limited attention is given to the influence of the deep layers at the recording station on the characteristics of the resulting ground motion. This may be particularly relevant when evaluating the appropriateness of using such motion as input in one-dimensional equivalent linear SRA. This traditional approach implicitly assumes that the Vs profile and the site kappa (Anderson and Hough, 1984) below the assumed depth of the EHS are identical to the Vs and kappa values at the recording station. Under these conditions, the recorded ground motion is assumed to reflect the effects of the layers below the top of the EHS boundary. This premise is rarely met, and the degree to which it alters the estimates of site response has not been formally studied in the past. This research focuses on the potential systematic errors that can result if the profile at the recording station is significantly different from the rock profile at the site being analyzed. Thus, adjustments to ground motions are proposed, so that they are compatible with the assumed EHS. Case histories, based on sites located in the cities of San Pedro and Concepción in Chile, will be presented as examples of the applicability of the proposed methodology. One corollary of the Vs-kappa correction factors is that they allow for the expansion of the range of analog stations from which ground motions can be selected for input into SRA.
Evaluating Installation Disturbance from Helical Piles and Anchors Using Compression and Tension Tests
Authors: Lutenegger Alan J.  , Tsuha Cristina de H.C.
Published: February 2025

Screw-Piles and Helical Anchors have been in use throughout the world to support a variety of structures for the past 180 years and have seen a dramatic increase in use during the past 20 years. One of the important issues that must be considered in design is the degree of disturbance to the soil during installation. This may be especially important for tension applications in saturated fine-grained soils where the disturbance from installation may produce a reduction of the undrained shear strength and in structured soils where the installation produces a breakdown in the natural soil structure. In tension, the soil engaged in developing load capacity has unavoidably experienced the passing of the helical plates whereas in compression the soil beneath the lead plate is undisturbed. In order to evaluate the level of disturbance produced in different soils during installation, single-helix and multi-helix anchors were installed at several sites in the US and Brazil. Load tests were conducted in compression and tension to evaluate the difference in load behavior. The results show that even with perfect installation practice the soil is disturbed to some degree as a result of rotation of the helices during installation. The disturbance increases with additional helical plates which produces a reduction in individual plate load capacity. Using the results from compression and tension loading it is possible to define a capacity ratio which is in effect a disturbance factor for different soils. These results should help design engineers by recognizing the degree of installation disturbance that can occur and how it influences capacity.
Ensayos de pilotes estáticos y dinámicos en la nueva Facultad de Enfermería
Authors: Gutiérrez Álvaro  , Cornelius Valentina  , Neme Mariano  , Peluffo Adrián
Published: February 2025

El Laboratorio de Control de Calidad de Fundaciones fue responsable de la ejecución de los ensayos de recepción de los pilotes para la nueva Facultad de Enfermería. Los mismos fueron diseñados mediante fórmulas empíricas basadas en el SPT. Se realizaron diez ensayos de carga dinámicos entre los que se incluye un pilote de prueba, al cual se le realizó además un ensayo de carga estático. Se comprueba que los pilotes están sobredimensionados discutiéndose las causas de ello.
Comparison of laboratory and field techniques to measure shear wave velocity in Texcoco Lake Clay
Authors: Ovando-Shelley Efraín  , Rodríguez Miguel  , Flores-Castrellón Osvaldo  , Flores-Guzmán Mario
Published: February 2025

We analyse shear wave velocities obtained from field tests performed at a site in the former Texcoco Lake, some 15 km north east of central Mexico City. The objective of our study was to evaluate shear wave velocity profiles obtained by combining the Microtremor Analysis Method (MAM) and the Multichannel Analysis of Surface Waves (MASW). We compare these profiles with those obtained using the suspension logging technique and with a seismic Marchetti dilatometer. The results of laboratory tests (resonant column and bender element tests) are also brought into our discussion. Field and laboratory data show that the shear wave velocity values obtained with the experimental techniques presented here are scattered within a relatively narrow range. Regarding the combined MAM-MASW method, our results show that this method reliably provides shear wave velocity values that closely resemble those obtained with the other methods down to about 40 m. The MAM-MASW is cheaper, it is less time consuming and it requires a modest investment in equipment. Nevertheless, a high degree of expertise is required to interpret and analyse the time signals obtained here.
Pruebas de integridad a gran escala en pilas de cimentación del Muelle Multipropósitos C, en el Puerto de Montevideo, Uruguay
Authors: Clavellina Miller J. Guillermo  , Monroy Salgado Rogelio  , Gutiérrez Álvaro  , Álvarez Camilo  , Andre Florent  , Paulín Aguirre Juan
Published: February 2025

El Muelle C, ubicado en el Puerto de Montevideo, Uruguay, actualmente en proceso de construcción, está estructurado por una losa de 373 m de largo y 36 m de ancho, apoyada en 256 pilas. Durante la construcción de una de las pilas, de acuerdo con los registros de los ensayes de compresión simple sobre algunas de las muestras del concreto empleado, se detectaron problemas en el fraguado del mismo, lo que generó incertidumbre acerca de la calidad del concreto colocado en cierta altura de la pila. Con el fin de confirmar la integridad estructural de dicha pila, se realizó una prueba de integridad a gran escala, basada en el procedimiento empleado para la realización de pruebas de carga dinámicas. El presente documento describe el procedimiento general de la prueba, los resultados y las conclusiones obtenidas.
Determination of Soil Physical Indices in the Field Using the Electrical Conductivity
Authors: Vaillant João Marcos  , Santos Osório José
Published: February 2025

This study aimed to develop a fast method for determination of soil compaction parameters in the field. The electrical conductivity was used to verify correlations with those parameters, since it is known the existence of mathematical relations between these variables. The study was conducted in two stages. In the first one, it was used five random samples of soil from regions close to the capital of Minas Gerais, Brazil. In a second stage, other five samples were incorporated and tested to broaden the scope of the data and confirm the established correlations. All samples were characterized according to the procedures of the Brazilian technical standards. The electrical conductivity was measured by a DC voltage source of 12V, using two copper plate electrodes, 1 mm thick each. The results confirmed the mathematical relations of the electrical conductivity with soil compaction parameters (maximum dry density and optimum moisture) in such a way that they can be estimated if only two points in the regression line between moisture and conductivity are known. Consequently, it is also possible to estimate the minimum void ratio of soil, that is, the one for which the degree of compaction is 100% of the normal Proctor energy. It is concluded that the proposed method is easily applied to field situations, where it will facilitate professionals to make prompt and appropriate decisions on the incorporation of deposits which have not been studied in laboratory yet. Furthermore, the degree of landfill compacting, in general, can be checked with less consumption of time and materials.
Geotechnical and Geophysical Properties of Deep Marine Sediments Recovered from the Gas Hydrate Occurrence Regions in Ulleung Basin, East Sea, Korea
Authors: Kim Hak-Sung  , Cho Gye-Chun
Published: February 2025

The vast amounts of gas hydrate reserves have drawn scientific attentions as a potential energy resource. For gas hydrate production, gas hydrate-bearing sediments should be depressurized below the gas hydrate equilibrium pressure. The depressurization of a gas hydrate reservoir can lead to several geotechnical problems such as the destabilization of the production well, settlement of the seafloor installation, or slope failure of the production site. Thus, it is important to determine the geotechnical characteristics of gas hydrate-bearing sediments. This study determined the geotechnical and geophysical properties of deep marine sediments in Ulleung Basin, East Sea using minimally disturbed natural samples retrieved during the Second Ulleung Basin Gas Hydrate Expedition (UBGH2). Conventional geotechnical engineering test characterize the sediments highly plastic silty soils; they exhibited low hydraulic conductivities, and high compressibility when subjected to an increase in effective stress. It is expected that depressurization during gas hydrate production at the investigated sites would cause a significant amount of compaction around the production hole. In addition, the prior occurrence of gas hydrates in the samples was verified through a comparison of water content, compressibility, and electrical resistivity.
Changes in geotechnical properties of urban soils during carbonation
Authors: Jorat Ehsan M.  , Kolosz Ben W.  , Sohi Saran P.  , Lopez-Capel Elisa  , Manning David A.C.
Published: February 2025

Urban soils that contain materials derived from demolition undergo carbonation as a consequence of a reaction between Ca derived from cement and concrete, and carbonate ultimately derived from the atmosphere. Estimated rates of CaC03 accumulation are equivalent to the removal of 150T CO2ha−1yr−1. Although this process has benefits for carbon capture, the formation of CaCO3within the soil potentially affects the geotechnical properties. Trial pits at a number of locations have consistently yielded CaCO3contents of 20 wt% from 0–1 m depth. Carbonate has formed in intergranular space within the soil, possibly with improvements in strength but also with changes in permeability that may affect through drainage. This paper investigates the limits to CaCO3formation imposed by soil porosity for a number of artificial soils: ‘well sorted sand or gravel’, ‘sand and gravel, mixed’, ‘silt’ and ‘clay’. Calculated values for CaCO3for the various soil types are used to determine limits to CaCO3formation within the first 1 m of sediments at the Science Central Site in Newcastle upon Tyne, UK, using information derived from five trial pits within made ground.
Oil and Gas Geomechanics: Initial State of Stresses
Authors: Lopez-Puiggene Eva  , Alvarellos-Iglesias Jose  , Segura-Serra Jose Maria  , Gonzalez-Molano Nubia A.  , Vargas Mendoza Pablo E.  , Ibañez-Martinez Enric  , Lakshmikantha M.R.
Published: February 2025

The productivity of a hydrocarbon reservoir (gas or oil) is strongly conditioned by the strain-stress rock behavior, the permeability dependence on stress changes and the in-situ stress conditions both at pre- and during production. For many years, simple compressibility and permeability models were used to take into account the rock strain-stress behavior. However, oil industry is moving to an area where reservoirs complexity is increasing. More complex geology and fluid saturation models (gas, heavy oils) lead to a scenario where simple models fail on the prediction of the reservoir performance (e.g. shale gas reservoirs). Those predictions are important to optimize the field development plans.
Stability of a slope to the filling of a reservoir, understanding the behavior of a fractured rock mass
Authors: Montiel Edgar  , Parra Natalia
Published: February 2025

During the stage of reservoir filling in a dam located in the north of Mexico, the presence of a series of cracks was reported along a hillside. The rock mass is this slope began a process of moving at a rate of 4 cm/day, decline until 0.5 cm/day at the last measurement step. Due the rate of apparent continuity in the movement of the rock mass, it was necessary to assess whether it was feasible the abrupt failure of the slope, whose volume is approximately three million cubic meters, which should slide surf that would provoke at risk the safety of the dam. From a series of studies aimed at defining the geomechanical characterization of the slope, it was possible to establish the existing materials and geological structures, allowing the development of a series of analysis which results provide conclusions about the behavior of the slope to changes producing variations of the reservoir as well as the forecast of the effects for quick emptying and an unfavorable impact of earthquake in the area. In order to show the procedure followed and the results obtained in this evaluation, this paper validate the response of the numerical model through a comparison with traditional limit equilibrium analysis is presented, allowing to define the likely behavior of rock mass located in a geologically extensional region in which there is a change in the stress state due to anthropogenic activities such as the construction of a hydroelectric project
French Expertise in rockfall protection – a case study
Authors: Berger Thomas  , Helary Vincent  , Villard Nicolas  , Velu Marc
Published: February 2025

Slopes instabilities pose a significant risk to infrastructures and development especially in mines and mountainous areas. The management of geohazards in France takes place in a wide range of environments exposed not only to rockfall, but also avalanche, flooding, earthquake or volcanoes, from high mountains to tropical islands territories. Therefore a specific approach has been developed from decades of experience (since 1860) and now known to be one of the most conservative in Europe. Indeed risks are being increased in the French Alps by global climate change (Mediterranean storms) at the same time as the density of infrastructure, mines or industrial projects increase. Over recent years research and new developments are increasing knowledge of slope stability, leading to new engineering methods and mitigation options especially in the range of dynamic barriers conception or high energy passive bunds. Experience between private companies and public services have been applied. This diversity through centuries of experience and some major disasters, led to a balanced management strategy always bringing in pioneering measures such as recent European and French guidelines. Finally, operational feedback of some cases studies of roads and industrial sites protection are described as example. This shows mainly the importance of the analysis process through fine engineering studies and the combination of different protective strategies and lightweight preventive measures.
Stochastic Analysis of Hydraulic Fracture Propagation using the eXtended Finite Element Method and Random Field Theory
Authors: Youn D.-J.  , Griffiths D.V.
Published: February 2025

Hydraulic fracturing is an important technology to increase the amount of production extracted from unconventional hydro-carbon reservoirs. In spite of the recent proliferation of the stimulation technique, the technical understanding of how fractures initiate, propagate, and interact with material heterogeneity is not well established. The need for improved scientific understanding of this methodology has motivated this research, which seeks to develop probabilistic finite element software for modeling fracture propagations in random formations. The finite element development proposed herein will combine the eXtended Finite Element Method (XFEM) with random field theory to characterize fracture propagation within heterogeneous tight hydro-carbon reservoirs without any need for re-meshing. The XFEM not only has a potential for improved modeling accuracy, but also reduces computational costs that might be needed when using a standard finite element method. Stochastic modeling of hydraulic fracturing will be used to further account for randomly distributed formation properties of the tight formation and the resulting various hydraulic fracturing patterns. The new methodology from this research will be called eXtended Random Finite Element Method (XRFEM). When combined with a Monte-Carlo simulation approach, this methodology will lead to probabilistic information on the response of various formations and enable better technical and financial risk management of unconventional reservoir stimulation. Parameters used in the XRFEM modeling of well stimulation are subject to different types and levels of uncertainties caused by inherent spatial variability in geological formations.
Study of Relationship Between Wear Tests on Rocks by Slake Durability, Micro-Deval and Los Angeles Abrasion Tests
Authors: Dias Filho José Luiz Ernandes  , Santos Vitor Guimarães Pereira  , Maia Paulo Cesar Almeida  , Xavier Gustavo de Castro
Published: February 2025

This paper presents a critical analysis of three major wear tests on rock: slake durability, Los Angeles and micro-Deval. These tests are amply used as a way to characterize the rocks used in construction. With large scale projects of infrastructure across the country and around the world at an accelerated rate, the growing search for more rock materials, it generates an increasing demand of characterization for wear test. With the different exogenous environment in which there are geotechnical applications, the rock can suffer from various forms of degradation in the service time. Wear tests generate good results of durability and weight loss, which are the main factor of choice of rocks in the construction. The objective of this paper is to propose a correlation between these tests as [1] concludes his paper with the linear relationship of slake durability and micro-Deval test and proposing an idea of direct correlation to further testing and characterization deeper. The main variations of the tests are discussed in the literature and presented the results of the main adjustments made in abrasive tests and their characteristics. Analysis of the results shows and confirms the previous idea and presents equations of correlation between the wear tests presented. The idea is not to discard the use of characterization tests, but rather to broaden the discussion on the subject and provide an alternative to laboratories with the absence of one or other equipment.
Determination of the Stress State in the Andean Cordillera Frontal near the Border between Argentina and Chile
Authors: Martino Roberto D.  , Giambastiani Mauricio  , Rocca Ricardo J.  , Guereschi Alina B.  , Huerta Soaje Pedro J.  , Marcet Juan E.
Published: February 2025

The initial state of stress is an important parameter in underground excavations. From its knowledge, it is possible to calculate the stresses induced around the excavation and the necessary support for stabilization. This task becomes critical when the excavations have great dimensions such as caverns and when rock overburden is significant. Different methodologies are discussed, including simple regional stress maps, the survey of surface paleostress and hydraulic fracturing executed in borehole between 500 and 800 m deph. These methodologies have been applied in the Andean Cordillera Frontal, where the Agua Negra tunnel will be built between Argentina and Chile. This area is affected by the subduction of the Nazca plate beneath the South American plate. This setting generates that the greatest principal stress σ1has a W-E orientation and relationship with the vertical stress (σ2) reaches about 1.4.
Mechanical behaviour of Carrara marble rock mass related to geo-structural conditions and in-situ stress
Authors: Gullì Domenico  , Pellegri Maura  , Marchetti Daria
Published: February 2025

For enhancing stability evaluations and safety conditions of Carrara marble quarries (Apuan Alps, Tuscany, Italy) the UOIM (Operative Unit of Mining Engineering) has developed a twin approach of analysis: this is based, on one hand, on the application of an experimental campaign addressed to in-situ stress estimation, large scale geo-structural analysis and rock mass characterization and, on the other hand, on numerical analyses that can be able to modeling materials with multiple intersecting discontinuities when simulating excavation. The aim of this activity, is to drive the concept that, apart from the obvious objective of exploit a natural resource, the main purpose of the quarry project should be to prevent instability of the rock mass, in every step of the foreseen exploitation. The main results of the discontinuous numerical analysis are presented with reference to the reported case of Fantiscritti quarries assuming a crack initiation threshold for rock mass based on deviatoric stress levels, following the relation σ1−σ3≅0.2σc(20±4 MPa).
Analysis of the Design and Stability of the Retaining Walls Built by the Incas
Authors: Vallejo Luis E.  , Fontanese Melissa  , Estrada Nicolas
Published: February 2025

Before the conquest, the Inca Empire consisted of some 10 million inhabitants. Political unification required a superb highway system that included at least 40,000 km of serviced roads. When an Inca road followed the contour of a mountain, earth embankments needed to be constructed. For stability, these earth embankments required the building of retaining walls. The Incas also built retaining walls for their agricultural terraces. These terraces were located in steep rock slopes. This study involves the stability analysis of the retaining walls built by the Incas. This analysis was made with respect to static and earthquake loads. The Inca walls were made by piling up rock pieces made of granite, a very durable material. The size of the rocks used varies between 10 cm and 2 meters. The source of the stability of the walls rests on the frictional resistance between the rock pieces. This frictional resistance was found to be greater than the pressures exerted by the soil abutting the walls. Since no cement was used in the building of the walls, these are freely drained. These retaining walls have been stable for more than 500 years. In light of this remarkable achievement in sustainable engineering, it is undoubtedly very important to investigate the reason for their long-term stability so that this knowledge can be applied to modern engineering design problems. The stability and sustainability analyses of the Inca walls were made using field, theoretical and numerical investigations.
Roughness characterization of discontinuity sets by profilometer and scanner images
Authors: Monticeli João P.  , Cantarella Vitor P.  , Cacciari Pedro P.  , Futai Marcos M.
Published: February 2025

Certain tunnels of Vitória-Mina Railway have presented rock fall problems which do not represent major risks, but can impair the railway operation. The TUNELCON Project, partnership between Vale SA and Escola Politécnica da Universidade de São Paulo (EPUSP), seeks to study the geomechanical behavior of these tunnels trough laboratory tests, geological and geotechnical mapping and numerical analyses. Therefore, it is important to collect large amount of data regarding to the rock mass geological and geotechnical characteristics that will be useful in further analysis.In this article the results of the roughness characterization of different discontinuity sets showed high variability for the shear fractures and foliation while relief fractures presented more constant values. The roughness was characterized by profilometer (Barton profilometer) and by 3D terrestrial laser scanner (3DTLS) images and their results were compared. Several Discontinuities from drill cores samples and 3DTLS mapping were used for this investigation.
Rough Set Significant Reduction and Rules of Intrusion Detection System
Authors: Sulaiman Noor Suhana  , Bakar Rohani Abu
Published: February 2025

Intrusion Detection System deals with huge amount of data which contains irrelevant and redundant features causing slow training and testing process, also higher resource consumption as well as poor detection rate. It is not simply removing these irrelevant or redundant features due to deteriorate the performance of classifiers. Furthermore, by choosing the effective and important features, the classification mode and the classification performance will be improved. Rough Set is the most widely used as a baseline technique of single classifier approach on intrusion detection system. Typically, Rough Set is an efficient instrument in dealing with huge dataset in concert with missing values and granularing the features. However, large numbers of generated features reducts and rules must be chosen cautiously to reduce the processing power in dealing with massive parameters for classification. Hence, the primary objective of this study is to probe the significant reducts and rules prior to classification process of Intrusion Detection System. All embracing analyses are presented to eradicate the insignificant attributes, reduct and rules for better classification taxonomy. Reducts with core attributes and minimal cardinality are preferred to construct new decision table, and subsequently generate high classification rates. In addition, rules with highest support, fewer length, high Rule Importance Measure (RIM) and high coverage rule are favored since they reveal high quality performance. The results are compared in terms of the classification accuracy between the original decision table and a new decision table.
Ex-Post-Facto estimate of performance at the offshore reclamation of airport Osaka/KIA
Authors: Akai K.  , Tanaka Y.
Published: February 2025

Reliability analysis was performed on the settlement performance of the first stage construction of KIA (Kansai International Airport). The analysis is based on the settlement measurements that are taken over the nine years period starting from the end of 1993, and also based on the soil investigation results for the Upper-Most Pleistocene Clay (Ma12). Based on the analysis, a possible range of future settlements, in probabilistic terms, of both the total and of the Ma12 stratum over the next 50 years is given. Also given is an evaluation on the performance of PTB (Passenger Terminal Building) of KIA that was made by examining the maintenance records of the differential settlement adjustments of its foundations.
Measurement of soil-water characteristic curves of quasi-saturated soils
Authors: Bicalho Katia Vanessa  , Znidarcic Dobroslav  , Ko Hon-Yim
Published: February 2025

Important geotechnical structures involve cohesive soil compacted either around or on the wet side of optimum water content. In general, at the corresponding saturation values, water component in soil voids is continuous but the air phase is not. The soil with entrapped air may be assumed to be in a state termed as “quasi-saturated”. The soil-water characteristic curve is often used to estimate unsaturated soil property functions. Since the measurement of pore air pressure in an occluded sample is extremely difficult, the data for the soil-water characteristic curve of quasi-saturated soils is not well defined. A simple experimental procedure for rapid measurement of continuous soil-water characteristics curves of quasi-saturated soils is described in this paper. The apparatus, testing procedures and results are presented and discussed. Data from the test results are used to validate a theoretical soil-water characteristic function involving discontinuous air phase derived by using the occluded state theory proposed by Schuurman (1966).