bluuebunny/crossref_metadata_2025 huggingface dataset:
Slope Stability Assessment Based on Limit Analysis
Authors: Wu Weigao
Published: February 2025

Most of the research findings in evaluating slope stability using limit analysis are chart-based. No such stability chart is available to cover a wide range of material strength, slope geometries and external disturbance. Practitioners find it difficult to use the charts for a specific slope project. Compared with a large number of existing commercial softwares based on limit equilibrium and FEM, the practical use of limit analysis is not yet mature. In this paper, the development of a software package for slope stability assessment based on limit analysis is introduced. Several demonstrations of its features and verifications with a commercialized FEM software Phase2 are given. Slope stability assessment based on limit analysis is more efficient and can provide almost identical results compared with Phase2.
Risk Assessment and Mitigating Measures Regarding Pile Installation at EBS Biohub Jetty
Authors: De Nijs R.E.P.  , Nap A.C.A.  , Korte W.  , Nederlof W.J.
Published: February 2025

During the design phase of the reconstruction of the existing mooring facility “EBS Biohub” at the port of Rotterdam, the Netherlands, a high risk profile was recognized in the proximity of four new dolphins next to the existing jetty. The risk originated from the greater installation depth of the dolphins related to the limited foundation depth of the existing foundations and from the structural analysis which indicated that the superstructure could only withstand limited settlement differences. Risk management aspects were incorporated in the contract by defining an observational approach involving monitoring of the structure and the subsoil. The contractor Geka offered a pile test at dolphins to be installed at a safe distance from the jetty. A number of test piles were installed at varying distances from the dolphins in order to detect settlements. The induced settlements were compared with a contractually defined criterion. Based on the test, two installation methods were in place. Two dolphins were installed under a slope in order to create a minimum of 5 m distance between the installation trajectory and adjacent piles. Two dolphins at shorter distance were placed while two adjacent piles per dolphin were cut from the jetty platform with an alternative support by a reaction frame with active hydraulic compensation at service load. All criterion on bearing capacity, vibration levels, settlements, deformations and cone resistance were met. No damage on nor deformation of the existing structure was encountered resulting in a success in terms of budget, planning and risk management.
Assessment of Reliability-based Serviceability Limit State Procedures using Full-Scale Loading Tests
Authors: Huffman Jonathan C.  , Martin John P.  , Stuedlein Armin W.
Published: February 2025

Geotechnical reliability-based limit state design methodologies are rapidly evolving to meet the demands of various applications. However, the accuracy of these new procedures should be independently assessed and improved as new loading test data is made available. This paper focuses on the assessment of two relatively new serviceability limit state (SLS) procedures developed for immediate displacement of spread footings supported on clay and on aggregate pier improved clay. These procedures were developed using a database of full-scale loading tests reported in the literature, and incorporate estimates of and variability associated with the bearing capacity, or ultimate limit state (ULS) and bivariate normalized bearing pressure-displacement models. Independent evaluations of these two SLS models are made using new full-scale loading tests on unimproved ground and aggregate pier improved ground. Comparison of observed and expected normalized bearing pressure-displacement curves and empirical cumulative distribution functions highlight the importance of footing/soil representation in the source databases and the impact and importance of differentiating between intra- and inter-site variability.
Uncertainties in Redesigning an Existing Quay Wall
Authors: Oung Oubbol  , Brassinga Henk
Published: February 2025

A feasibility study was carried out on the redesigning of an existing quay wall of a core harbor in the Netherlands, which was more than 45 years old. The geotechnical behavior of the existing quay wall, especially because of its age, as a response to the maximum load change is undoubtedly the uncertain parameter here. The design and redesign aspects have been considered: the evaluation of the current situation, the remaining lifetime of the structure and other aspects like corrosion and fatigue of the construction materials and the change in design standards between the past and the future situations. No monitoring and measurements were available. Inspection on steel structural elements showed some corrosion, to which extend was unknown. The history of load usage of the quay wall was not registered. After a preliminary redesign, it is clear that some uncertainties would remain. It was concluded that the lack of information in the current situation constitutes the main obstacle to a straightforward redesign and the use of Finite Element Method modelling reveals a failure mechanism, which was not encountered earlier. Because of the technical risks, a redesign of such existing and complex quay wall would necessitate an extensive design procedure to increase reliability.
How To Determine the Phreatic Surface in a Dike during Storm Conditions with Wave Overtopping: A Method Applied to the Afsluitdijk
Authors: de Raadt Wilhelmina S.  , Jaspers Focks Dirk-Jan  , van Hoven André  , Regeling Eric
Published: February 2025

The most famous dam of the Netherlands, the Afsluitdijk, is in need of renovation. Hydraulic conditions for the year 2050, for some aspects even 2100, must be considered during the renovation of the dam originally constructed 1927-1933. A combination of sea level rise due to climate change and a change in the applied statistical methods result in design conditions that are, at some locations, meters higher than those used a century ago. In a mission to retain the required level of safety while keeping expenses at a minimum, several innovative designs are considered; one of which is to allow very large overtopping discharges by making the dam resilient to erosion. However, calculations have shown that the overtopping values can be over 10 liters per second per meter dam, and the effect of this overtopping on the Afsluitdijk is unknown.
Identification and Treatment of Erodible Clays in Dikes
Authors: Nagy Gábor  , Nagy László
Published: February 2025

When it comes to flood protection, the established method is to use impermeable material in dikes, to prevent seepage. This material is usually some kind of clay soil which is considered as impermeable and erosion-resistant. Dispite that, in many occasions not only seepage, but the failure of the dam occured due to surface erosion, because these kinds of irregular soils are barely investigated, and their presence are not considered during the phase of designing.
Probabilistic Analysis of Velocity Distribution under Earth Embankments for Piping Investigation
Authors: Liu Kang  , Hicks Michael A.  , Vardon Philip J.  , Jommi Cristina
Published: February 2025

Piping has been attributed as a major cause of dam and embankment failures. Current national prediction models to predict piping use the hydraulic gradient between the upstream and downstream water levels as an indicator. They are deterministic and take no account of preferential pathways. However, piping usually initiates from a discrete downstream location and recent research indicates that piping happens when the water velocity reaches a critical value. The local velocity close to the downstream ground surface is strongly related to the inherent heterogeneity of the soil. This paper takes account of the spatial variability of hydraulic conductivity. Based on stochastic seepage analysis, local velocities in and under an embankment are computed. The results show that, when the coefficient of variation of hydraulic conductivity is small, the locations of the maximum local velocity from 500 realizations aggregate into a small area which is near the downstream toe of the embankment. In contrast, increasing the coefficient of variation scatters the possible locations of the maximum local velocity. Two typical situations are identified: one situation where the maximum local velocity is close to the downstream ground surface, and the other where the maximum local velocity is far from the downstream ground surface and located near the center of the foundation. In the first situation it is easier to reach the critical value to initiate piping because the maximum local velocity is near the ground surface, but it is also relatively easy to protect against. In contrast, in the second situation it is easier to form a passage for piping development once piping is initiated. This is due to the velocity towards the center of the foundation increasing.
A New Tool for Large-Area Analysis of Transient Pore Water Pressures in Layered Shallow Covers Prone to Failure
Authors: Salciarini Diana  , Castorino Giuseppe Claudio  , Cuomo Sabatino  , Tamagnini Claudio
Published: February 2025

In this paper we present a modified version of an existing, physically-based model for shallow landslide susceptibility analysis over large area. In general, the potentially unstable soil cover is considered uniform and homogeneous, over impervious underlying bedrock. In several case studies, this was proven to be unrealistic. The possibility of taking into account the detailed configuration of the soil cover allows having a more accurate estimate of the potentially unstable volumes, which determine the intensity of the considered phenomena. The newly–implemented tool was tested by comparing its results with those obtained from a Finite Element (FE) commercial code, solving the same 1D problem. Then, a parametric analysis was carried out by varying the permeability ratio between the two layers, with the aim of examining the influence of such parameter on the pore-pressure distribution along the vertical profile. As expected, as the permeability ratio increases, the underlying layer tends to behave as an impervious boundary. This increases the chance that only the most superficial soil layer fails. An analysis of the routine performance and efficiency was also done to investigate the response of the model with various tolerances and different spatial discretizations along the vertical profile. As main result, it is shown that the variability in ground conditions may highly affect the pore water pressures and the proposed seepage model can be successfully whether detailed stratigraphy site investigations are available.
Effect of Spatial Variability on Buried Footings
Authors: Li Jinhui  , Tian Yinghui  , Cassidy Mark J.
Published: February 2025

Natural soil is one of the most variable materials as a result of physical and chemical changes. The variation in soil properties significantly affects the failure mechanism and bearing capacity of a footing. This effect is further complicated by considering the spatial correlation of the soil properties. This study will investigate the influence of the spatial variability of a clay on the bearing capacity of a buried footing. The spatial variation of undrained shear strength of a clay is modelled by random fields, which is combined with a non-linear finite element analysis to obtain the bearing capacity of a footing. The random fields with different scales of fluctuation are modelled to reveal the effects of spatial variability. It is found that the mean values of bearing capacity of the foundation are the smallest when the scale of fluctuation is 0.1-1 times of foundation width. The coefficient of variation of the bearing capacity increases with increasing scale of fluctuation. When the scale of fluctuation is on the order of the foundation width the variation in bearing capacity is mainly due to the different shear paths developed in the random soil. When the scale of fluctuation is much larger than the foundation width, the variation in bearing capacity is mainly due to the distinct soil strength in different realizations.
Risk Analysis of Earthquake-Induced Submarine Slope Failure
Authors: Rodríguez-Ochoa Rafael  , Nadim Farrokh  , Cepeda José M.
Published: February 2025

This paper presents an offshore risk analysis in a systematic manner to assess the influence of earthquake-induced submarine slope failure on offshore structures. The risk analysis is carried out for the future development of a natural gas field in deep waters in the south part of the Gulf of Mexico. The study accounts for all the elements in the conventional risk formulation: Risk = Hazard × Consequences. The hazard analysis was performed in two steps: first estimating the probability of earthquake-induced slope failure by using the slope failure fragility curve approach; and second estimating the probability of failed sediments impacting offshore structures by running debris flow numerical simulations in a Monte Carlo method framework. The consequences were estimated focused solely on the damage to offshore structures, in monetary terms, and the development of vulnerability curves as function of the velocity and the thickness of the moving mud flow that may evolve from the failed sediments.
Resource Allocation in Industrial Cloud Computing Using Artificial Intelligence Algorithms
Authors: Sheuly Sharmin Sultana  , Bankarusamy Sudhangathan  , Begum Shahina  , Behnam Moris
Published: February 2025

Cloud computing has recently drawn much attention due to the benefits that it can provide in terms of high performance and parallel computing. However, many industrial applications require certain quality of services that need efficient resource management of the cloud infrastructure to be suitable for industrial applications. In this paper, we focus mainly on the services, usually executed within virtual machines, allocation problem in the cloud network. To meet the quality of service requirements we investigate different algorithms that can achieve load balancing which may require migrating virtual machines from one node/server to another during runtime and considering both CPU and communication resources. Three different allocation algorithms based on Genetic Algorithm (GA), Particle Swarm Optimization (PSO) and Best-fit heuristic algorithm are applied in this paper. We evaluate the three algorithms in terms of cost/objective function and calculation time. In addition, we explore how tuning different parameters (including population size, probability of mutation and probability of crossover) can affect the cost/objective function in GA. Depending on the evaluation, it is concluded that algorithm performance is dependent on the circumstances i.e. available resource, number of VMs etc.
Towards Unsupervised Learning, Classification and Prediction of Activities in a Stream-Based Framework
Authors: Tiger Mattias  , Heintz Fredrik
Published: February 2025

Learning to recognize common activities such as traffic activities and robot behavior is an important and challenging problem related both to AI and robotics. We propose an unsupervised approach that takes streams of observations of objects as input and learns a probabilistic representation of the observed spatio-temporal activities and their causal relations. The dynamics of the activities are modeled using sparse Gaussian processes and their causal relations using a probabilistic graph. The learned model supports in limited form both estimating the most likely current activity and predicting the most likely future activities. The framework is evaluated by learning activities in a simulated traffic monitoring application and by learning the flight patterns of an autonomous quadcopter.
Dynamic Bayesian modeling for risk prediction in credit operations
Authors: Borchani Hanen  , Martínez Ana M.  , Masegosa Andrés R.  , Langseth Helge  , Nielsen Thomas D.  , Salmerón Antonio  , Fernández Antonio  , Madsen Anders L.  , Sáez Ramón
Published: February 2025

In this paper we perform an exploratory analysis of a financial data set from a Spanish bank. Our goal is to do risk prediction in credit operations, and as data is collected continuously and reported on a monthly basis, this gives rise to a streaming data classification problem. Our analysis reveals some practical problems that have not previously been thoroughly analyzed in the context of streaming data analysis: the class labels are not immediately available and the relevant predictive features and entities under study (in this case the set of customers) may vary over time. In order to address these problems, we propose to use a dynamic classifier with a wrapper feature subset selection to find relevant features at different time steps. The proposed model is a special case of a more general framework that can also accommodate more expressive models containing latent variables as well as more sophisticated feature selection schemes.
Goal-driven, assistive agents for instructing and guiding user activities
Authors: Rafferty Joseph  , Nugent Chris  , Liu Jun  , Chen Liming
Published: February 2025

Current ambient assistive living solutions have adopted a traditional sensor-centric approach, involving data analysis and activity recognition to provide assistance to individuals. The reliance on sensors and activity recognition in this approach introduces a number of issues. This study introduces a novel approach to assistive living which intends to address these issues via a paradigm shift from a sensor centric approach to a goal-oriented one. The goal-oriented approach focuses on identification of user goals in order to pro-actively offer assistance by either predefined or dynamically constructed video-based instruction. This extended abstract introduces the architecture of this goal-oriented approach, covers the novel developments required to realize it and discusses the current state of the research.
Predicting Cyber Vulnerability Exploits with Machine Learning
Authors: Edkrantz Michel  , Said Alan
Published: February 2025

For an information security manager it can be a daunting task to keep up and assess which new cyber vulnerabilities to prioritize patching first. Every day numerous new vulnerabilities and exploits are reported for a wide variety of different software configurations. We use machine learning to make automatic predictions for unseen vulnerabilities based on previous exploit patterns. As sources for historic vulnerability data, we use the National Vulnerability Database (NVD) and the Exploit Database (EDB). Our work shows that common words from the vulnerability descriptions, external references, and vendor products, are the most important features to consider. Common Vulnerability Scoring System (CVSS) scores and categorical parameters, and Common Weakness Enumeration (CWE) numbers are redundant when a large number of common words are used, since this information is often contained within the vulnerability description. Using machine learning algorithms, it is possible to get a prediction accuracy of 83% for binary classification. In comparison, the performance differences between some of the algorithms are marginal with respect to metrics such as accuracy, precision, and recall. The best classifier with respect to both performance metrics and execution time is a linear time Support Vector Machine (SVM) algorithm. We conclude that in order to get better predictions the data quality must be enhanced.
Explaining Work Exhaustion From a Coping Theory Perspective: Roles of Techno-Stressors and Technology-Specific Coping Strategies
Authors: Gaudioso Fulvio  , Turel Ofir  , Galimberti Carlo
Published: February 2025

The purpose of this study is to theoretically develop and empirically examine a general coping theory model which explicates the indirect effects of key job-related techno-stressors on job exhaustion. Through this study, we show that techno-stress creators are detrimental to employee well-being and should be treated accordingly. Specifically, we first argue that key techno-stress creators on the job, namely techno-invasion and techno-overload, drive unpleasant states such as work-family conflict and distress. Next, we rely on general coping theory and argue that people respond to these states differently, but with both adaptive and maladaptive technology-specific coping strategies. Adaptive coping behaviors are argued to ultimately reduce work exhaustion, and maladaptive coping strategies are argued to increase it. The proposed model was tested and validated with structural equation modeling techniques applied to self-reported data obtained from a sample of 242 employees of a large organization in the United States. Implications for theory and practice are discussed.
Decision Making and Cognitive Behavioral Flexibility in a OCD Sample: a Study in a Virtual Environment
Authors: la Paglia Filippo  , la Cascia Caterina  , Rizzo Rosalinda  , Riva Giuseppe  , la Barbera Daniele
Published: February 2025

Neuropsychological disorders are common in Obsessive-Compulsive Disorder (OCD) patients. Executive functions, verbal fluency and verbal memory, shifting attention from one aspect of stimuli to others, mental flexibility, engaging in executive planning and decision making, are the most involved cognitive domains. We focus on two aspects of neuropsychological function: decision making and cognitive behavioral flexibility, assessed through a virtual version of the Multiple Errand Test (V-MET), developed using the NeuroVR software. Thirty OCD patients were compared with thirty matched control subjects. The results showed the presence of difficulties in OCD patients with tasks where the goal is not clear, the information is incomplete or the parameters are ill-defined.
Behaviour of Granular Materials for Pavements in a Hollow Cylinder Apparatus
Authors: Caicedo Bernardo  , Ocampo Manuel  , Vallejo Luis
Published: February 2025

Unbound granular materials used in pavement structures are subjected to a complex stress path that includes rotational stresses. Hollow cylinder apparatuses (HCAs) are suitable laboratory devices for reproducing stress paths found in the field. However, as the size of the HCA depends on the size of the granular particles, their use for testing unbound granular materials for pavements has received limited attention in the literature. This paper presents some results about the behavior of granular materials for pavements tested in a hollow cylinder apparatus. This large HCA has hydraulic actuators for vertical movement and torsion while shear and vertical stresses are servo-controlled to reproduce stress paths produced by a heavy vehicle moving on a pavement structure. Confining stress is applied using rings with controllable stiffness. The results show the effect of stress rotation on the behavior of unbound granular materials used in pavement structures.
Soil Dewatering Modeling in an Spatially Variable Soil Mass
Authors: Napa-García Gian Franco  , De Godoy Vanessa Almeida
Published: February 2025

This paper presents a brief study of the impact of the spatial variability of the hydraulic conductivity on the response of a soil mass before a range of dewatering demands. Spatial variability of the soil mass was characterized and handled using geostatistical tools and the inference of the spatial distribution of the hydraulic conductivity was performed using the Smoothing Corrected Ordinary Kriging [1]. A two-dimensional FLAC3D [2] model was implemented to receive the inferred values of conductivity. In addition, three homogeneous configurations of the hydraulic conductivity were also evaluated using FLAC3D to serve as comparison benchmarks, i.e. mean value, 5% percentile and 95% percentile. Results showed that the consideration of homogeneous properties yields large errors of the order of meters in comparison with the heterogeneous approach. The homogeneous mean valued model presented the closest response to the heterogeneous model with errors of about 1 m for water outflow greater than average hydraulic conductivity. Conversely, small errors were found for small water outflow below the mean hydraulic conductivity. Finally, our results suggest that mean properties may be used to model the dewatering process with caution for water outflow values up to the average value of the hydraulic conductivity.
Evaluation of the Shear Strength of Binary Granular Mixtures Using Direct Shear Tests Mixture Theory
Authors: Vallejo Luis E.  , Lobo-Guerrero Sebastian
Published: February 2025

Many natural slopes and rock-fills are made of a mixture of rock fragments and sand. To analyze their stability, knowledge of how sand-rock mixtures fail during shear is needed. For this purpose, direct shear tests were carried out in an open face, plane stress direct shear apparatus (PSDSA). The open face allows the recording of the changes in fabric that takes place in the shear zone. The granular mixture used consisted of a set of wooden rods 4.2 mm and 12 mm in diameter and both having 25 mm in length. The small rods simulated a granular matrix in which large particles are embedded. The surface of the small rods was shaved so they had a polynomial cross sectional area. The large rock particles were simulated by the 12 mm cylindrical rods that were placed in the middle of the mixture. The mixtures covered a square area having 7.62 cm in length. The shear strength of the mixtures was obtained using direct shear test results and was also calculated using mixture theory. The shear strength calculated using both methods gave similar results.
Normalização da Resistência à Compressão Simples de Mistura Areia com Cimento em Função do Tempo de Cura
Authors: Marques Sérgio  , Consoli Nilo Cesar  , Festugato Lucas  , Sonaglio Gonçalo
Published: February 2025

A busca por novas soluções técnicas que tornem as obras de engenharia mais econômicas e com a mínima agressão ao meio ambiente, tem sido uma das linhas de pesquisa do grupo de Geotecnia da Universidade Federal do Rio Grande do Sul (UFRGS). O objetivo do trabalho foi buscar a nonnalização da resistência à compressão simples (qu) com a relação vazios/cimento (η/Civ) e o tempo de cura (t). Depois de apresentada a nonnalização, um programa laboratorial foi realizado, a fim de comprovar a sua efetividade, e que consistiu em ensaios à compressão simples (qu) de misturas de areia com cimento para diferentes valores da razão vazios/cimento (η/Civ). Os resultados mostraram que se pode obter de uma maneira simples e rápida, e com uma boa confiabilidade, uma previsão da resistência à compressão simples (qu) em função da razão vazios/cimento (η/Civ) para diferentes tempos de cura.
Resilient modulus lime-treated expansive subgrade
Authors: Elkady Tamer  , Al-Mahbashi Ahmed  , Al-Shamrani Mosleh
Published: February 2025

Proper design of lime-treated subgrade requires knowledge of the stress-strain behavior under repeated traffic load. Limited research exists regarding the resilient modulus (MR) of lime-treated expansive soils. This study investigates the effect of lime treatment on the MR of an expansive soil from city of Tabuk in Kingdom of Saudi Arabia. Tests were performed in accordance with AASHTO T-307. Tests variables included lime content (2%, 4% and 6% by dry weight of soil) and curing period (7 and 28 days). Experimental results mainly revealed an increase in MRvalues due to lime treatment. In addition, the variation of MRwith deviatoric stress revealed trends of strain softening behavior in case of untreated soils and lime-treated soils cured for 7 days. However, lime treated soils cured for 28 days experienced some strain hardening behavior with high dependency on confining pressure. Furthermore, the MRof lime treated expansive subgrade was observed to be highly dependent on lime content and curing period. Finally, results were fitted using the three-parameter model to determine the stiffness coefficients (k1, k2, k3).
Evaluation of the Relation Between Unconfined Compressive Resistence and Flat Base Rod Resistance for a Sand-Cement Mixture
Authors: Rizzon M.M.  , Alves D.F.  , Consoli N.C.
Published: February 2025

The enhancement of local soils with cement for the construction of stabilized pavement bases, canal lining, and support layer for shallow foundations shows great economical and environmental advantages, avoiding the use of borrow materials from elsewhere, as well as the need of a spoil area. The focus of this paper is to present an evaluation of the resistance of a sand-cement mixture comparing the unconfined compressive resistance and a new test – flat base rod. This analysis was made to verify the existence of a linear relationship between the results of these two tests, already presented for other soils, like clays and silts. The sand studied was the Osorio Sand, a fine uniform quartz sand mixed with high initial strength cement (Type III). The tests were carried out for 3 periods of cure (3, 7 and 28 days), 3 void ratio (0.6, 0.7 and 0.8) and 4 cement ratio (1, 3, 5 and 7%). The water content was fixed in 10%. The flat base rod test consists of the measurement of the maximum strength applied in order to embed a flat base rod into a soil mass utilizing high sensibility dynamometric rings. By using the area of the base of the rod (circular base with 1cm2) and the maximum applied stress during the embedding of the rod into the soil mass, the peak strength is obtained (qe). Such strength, when compared directly with unconfined compression test (qu) results, showed excellent linear correlation which, in turn, showed the viability of this test for acquirement of compressive strength measurements.
Análise microestrutural da bioprecipitação de CaCO
Authors: Muñetón Claudia Maricela Gómez  , González Yamile Valencia  , Carvalho José Camapum de
Published: February 2025

Nas ultimas décadas tem se evidenciado, e de forma crescente, a preocupação causada pelos grandes impactos ambientais que a exploração de jazidas de materiais destinados às obras de engenharia civil está gerando, pois as exigências técnicas cada vez são maiores, devido às cargas ocasionadas pelo desenvolvimento industrial e aumento populacional, como consequência os custos de tais materiais terminam sendo mais elevados. Para atender a essas inquietudes, a procura de soluções econômica e ambientalmente sustentáveis tem gerado grandes linhas de pesquisa que apontam à utilização de processos biotecnológicos aplicados à melhoria de materiais cujos resultados são promissores. Em geotecnia os estudos no âmbito do uso da biotecnologia apontam principalmente à melhoria das propriedades hidráulicas e mecânicas dos solos mediante a produção de minerais via bioprecipitação. Nesse trabalho apresentam-se os resultados obtidos a partir da análise de imagens de microscopia eletrônica de varredura (MEV), onde foi estudada a indução da produção de precipitados de carbonato de cálcio (CaCO3) em amostras de solo laterítico, compactadas na umidade ótima das energias Próctor intermediária e normal, mediante a adição de um meio nutritivo denominado B4 [1]. Observou-se que dentro da população das bactérias endógenas do solo existem especies apropriadas para metabolizar o meio em menção, dando como resultado a produção de CaCO3, independentemente da energia de compactação utilizada.
Madero Office: Fundaciones con barretas y contenciones premoldeadas
Authors: Lopez Alfredo A.  , Quaglia Gastón  , Sfriso Alejo O.
Published: February 2025

La torre Madero Office, de 33 pisos, tiene una estructura principal que consiste de dos núcleos que soportan aproximadamente 270MN. Estos núcleos fueron fundados sobre grupos de barretas de alta capacidad, atravesando los suelos de la Formación Pampeano y penetrando en la Formación Puelche. El sector central de la estructura está fundado sobre pilotes y cabezales. El diseño y construcción de las barretas empleadas en Madero Office constituye la primer experiencia con esta técnica de fundaciones especiales en Argentina. La submuración perimetral fue ejecutada íntegramente con un sistema de pantallas delgadas premoldeadas de hormigón armado. Al igual que las barretas, fue la primera vez en emplearse esta técnica en Argentina. En este artículo se presentan algunos detalles técnicos del proyecto de fundaciones y contenciones.
Falencias en el diseño dejadas al descubierto por múltiples fallas de estructuras de contención durante el Fenómeno de La Niña en Colombia
Authors: Alvarez Lugo Jose Manuel
Published: February 2025

Durante el Fenómeno de La Niña, ocurrido en Colombia entre los años 2010 y 2011, se presentaron a lo largo de las vías del país, innumerables afectaciones a la infraestructura de carreteras. Entre los eventos más frecuentes estuvieron las fallas de un sinnúmero de estructuras de contención, que dejaron al descubierto, aspectos fundamentales en el diseño de este tipo de obras que se han pasado por alto. Este trabajo, mediante el análisis de la condición de falla presentada en cerca de 20 estructuras de contención, realiza un compendio de las principales falencias que se presentaron tanto en el diseño como en la construcción y que fueron condiciones fundamentales que permitieron que estas obras fallaran. Se analizan en el presente trabajo, falencias asociadas a la valoración de las condiciones del entorno (procesos de socavación, degradación de materiales rocosos blandos, erosión superficial, descoles inadecuados), a la estimación inadecuada de las superficies de falla probables, a la evaluación errónea de las posibles retrogresiones de la inestabilidad y a la subvaloración de las condiciones de desembalse rápido entre otros. El trabajo se nutre con imágenes de las obras falladas a la vez que se analizan conceptual y numéricamente las condiciones que permitieron la falla de las estructuras.
Particle-Size Segregation in Tailings Sand Dams
Authors: Figueroa Abraham  , Santos Eloy  , Sconagmillo Claudio  , Valenzuela Luis  , Tascon Andrés
Published: February 2025

Growth in production rate in large-scale metallic mines has resulted in an increasing demand for larger tailings disposal capacity. In the case of mines located in mountainous regions these larger tailings deposit frequently require the construction of high dams. Tailings deposits operating in Chile three decades ago required dams of about 150m maximum height. In the last decade dams more than 200m high have been designed and built [1][2] and even higher dams are now being considered in South America. Most of the tailings dams that started operation in the last decades are downstream or center line tailings sand dams with sand been deposited as hydraulic fill, with a limited maximum percentage of fines in the sand to guarantee an adequate permeability. Usually, hydraulic deposition of soils and specially of tailing sands leads to a variation of the particle size distribution along the downstream slope of the dam, the coarser particles being deposited at shorter distances. This hydraulic segregation depends mainly on the flow volume of the sand pulp been deposited, on the solids concentration of the pulp, and on length and slope of the dam [3][4]. In general, particle size segregation in tailings sand dams has not been analyzed in enough detail, since it did not have a great impact for the most common range of dam heights. Nevertheless, the impact of this segregation could become important in higher dams since an increase in the percentage of fines in the sand could cause a reduction in its permeability, shear strength, and cyclic resistance, which in turn could affect the stability of the dam.
Verificación de los parámetros de diseño geotécnico de la presa del Proyecto Hidroeléctrico Reventazón durante su etapa constructiva
Authors: Ruiz Roy  , Calderón Darío  , Avilés Eduardo
Published: February 2025

The Reventazón Hydroelectric Project, which involves the construction of a 130-m high CFRD dam, is being built in Costa Rica. The dam fillers are composed of alluvial materials from the Reventazón River, as well as materials from the excavation of the spillway, consisting of conglomerates and consolidated breccias mixed with alluvial gravel. This article aims to present the results of the test made during construction stage and the results provided by the installed instrumentation to make a check of the geotechnical design parameters.
Análisis de Estabilidad de Taludes para la Generación de un Mapa de Probabilidad de Amenaza ante Deslizamientos en la Zona de Pampahasi, La Paz – Bolivia
Authors: Fabiana Viscarra Agreda
Published: February 2025

La ciudad de La Paz cuenta con una topografía abrupta en forma de valle estrecho, presenta en la mayoría de su extensión condiciones geológicas inestables y es atravesada por más de 300 ríos los cuales han provocado considerables fenómenos de erosión y remoción en masa. Todos estos factores sumados con la indebida acción humana han desencadenado a lo largo de los últimos 10 años más de 900 casos de problemas geodinámicos, según la Dirección Especial de Gestión Integral del Riesgo (DEGIR) de la ciudad de La Paz. En general, esta problemática hace que la ciudad esté expuesta a riesgos de pequeña magnitud, frecuencia recurrente pero que en algunos casos han causado daños severos con connotaciones a nivel internacional como el denominado mega-deslizamiento de Callapa-Pampahasi ocurrido el 27 junio de 2011. Este evento fue catalogado como el desastre natural más grande en la última década a nivel local, generando grandes pérdidas económicas, con un área de afectación aproximada de 100 hectáreas, alrededor de 1000 casas destruidas y aproximadamente 5000 personas damnificadas.
Undrained Response of Sand Containing Non-Plastic Fines
Authors: Alberto-Hernandez Yolanda  , Towhata Ikuo
Published: February 2025

Current simplified procedures for estimating liquefaction resistance consider an increase in the measured SPT-N for sand containing fines. Nevertheless, it is not clear if this increase corresponds to an increase in resistance or to a decrease in penetration resistance due to fines compressibility. To date, several researchers have studied in laboratory the influence of non-plastic fines on the liquefaction resistance of sands considering different approaches in which they keep constant a density index for comparison such as void ratio, relative density, sand-skeleton void ratio or inter-granular void ratio, equivalent void ratio and inter-fine void ratio. This has led to divergent conclusions that will be described and explained in this paper. The interest in this topic has increased after the recent events of liquefaction in Taiwan, New Zealand or Tokyo, where liquefaction caused significant damage to buildings, houses, retaining structures and underground infrastructure. Sand retrieved from Tokyo Bay was studied in this research. A hollow cylindrical torsional shear apparatus was used to conduct a series of tests to determine the effect of non-plastic fines on the liquefaction potential of sand. Given the disagreement of the role of non-plastic fines in previous researches, it was decided to test samples at the same SPT N-value. The coefficient of volume compressibility, mv, was selected for comparison as it is inversely related to the SPT N-value. Samples were consolidated at the same mvvalue and then sheared under monotonic and cyclic loading. Later, the volumetric strain after liquefaction was also measured and results are presented herein and discussed. Relevant conclusions regarding the role of non-plastic fines on the undrained behavior of sands, are provided.
Pit Slope Recovery – Águas Claras Mine
Authors: Gobbi Felipe  , Fonini Anderson  , Tobler Daniel  , Sá Gilvan  , Farias Carlos  , Gomes Célio  , Denardin Bruno  , Flach Rodrigo
Published: February 2025

In 1992 a massive landslide had occurred at Águas Claras Mine, at that time it was operated by Minerações Brasileiras Reunidas, MBR. After this event slope stability studies were carried out in order to evaluate the remaining slope, which were considered acceptable. However erosion process leaded to shallow landslides -hence the crest of the mountain become a risk area, which is part of the national heritage Serra do Curral landscape. As consequence, in 2008 a stabilization solution consisting in a soil/rock nailing faced with high strength steel wire mesh and a drainage system, were designed. In 2013 the slope stabilization work was initiated. Nowadays the work is ongoing, with forty percent of the stabilization area concluded. A review of the executive design has been carried out simultaneously with the field work. In the first stage of the design, structural geologic aspects of the remaining rock mass were identified as constraint aspects on the failure mechanism. The nails were designed based on the structural conditions and joint shear stress parameters, defined by in situ and laboratory tests. So far the designed solution is performing accordingly, in order to avoid superficial slope instabilities.
Geotechnical investigation to assess the variability of the subsoil in the area of the Naval Cluster of Porto de Suape/PE
Authors: Victor Debora Feijó  , Freire Filipe Carnib  , Coutinho Roberto Quental
Published: February 2025

This article analyzes the variability of the subsoil found in a specific area of the Industrial Complex of Porto de Suape, Pernambuco (PE), ranging from outcropping residual soil to very soft mangrove alluvial soils. This paper discusses the main layers of soil, variability of the logs and characterization parameters of the soft to very soft clays found in that area. It will offer a brief description of the methodology and results of the tests done: Geophysics boring and drilling, vane shear, removal of undisturbed samples, characterization. A program of physical characterization laboratory tests was undertaken. To add to the studies, three-dimensional modeling was done using the data obtained from the investigations, facilitating viewing and understanding of the variability of this subsoil and its interfaces. For this purpose the Microsoft Excel software was used to create a database and AutoCAD Civil 3D for the three-dimensional model.
Unified approach on the interpretation of piezocone test data in a tropical soil site
Authors: dos Santos R.A.  , Rocha B.P.  , Napa-García G.F.  , Giacheti H.L.
Published: February 2025

The unified approach is a semi-empirical method, which incorporated the critical state soil mechanics theory for interpretation of piezocone tests. This paper discuss the applicability of this method to define stratigraphic logging and to estimate geotechnical soil parameters of a typical unsaturated tropical soil site from Brazil. The soil profile at the study site is clayey fine to medium sand with two well-defined layers: Cenozoic sediments overlaying Residual soil from Sandstone. It was concluded that this approach can be used for stratigraphic logging but soil sampling is needed to calibrate soil type. The complexity on the estimative of geotechnical parameters for these unusual soils can be associate to their cohesive-frictional behavior, unsaturated condition and to a possible partially drained condition at the CPTU standard penetration rate. The success of a site investigation will need additional in situ and/or laboratory tests to support geotechnical design on these non-text book soils.
Correlating In-situ Test Results for Dubai and Abu Dhabi Biogenic Calcareous Sands
Authors: Porcino Daniela  , Ghionna Vito Nicola  , Zimmitti Zaira
Published: February 2025

The paper examines SPT, CPT, and Seismic down-hole tests (DHT) data, collected from two relatively young biogenic calcareous sand deposits at Dubai and Abu Dhabi sites, in the United Arab Emirates (UAE). Tested materials consist mainly of fine to medium low plasticity silty sands. The analysis of test results highlights that most of the existing correlations between individual test data established for silica sands are not applicable to calcareous sands owing to grain crushability and related high compressibility of the latter ones. Modifications to the above mentioned correlations have been suggested to allow them to be applied with more confidence to calcareous sands. However, their reliability can be jeopardized by the spatial variability of test data, that is significant even at a local scale. Finally, the results obtained in the present study were compared with those gathered in other geotechnical investigations carried out in the same area, obtaining satisfactory agreement.
Geothermal Energy in Loess: A Detailed Numerical Case Study for Cordoba
Authors: Narsilio Guillermo A.  , Francisca Franco  , Ferrero Hugo  , Bidarmaghz Asal  , Serrano Carlos  , Carro Perez Magalí E.  , Makasis Nikolas  , Delacoste Evelyn
Published: February 2025

Ground-source heat pump (GSHP) systems efficiently heat and cool buildings using sustainable geothermal energy accessed via ground heat exchangers (GHEs). Loess covers vast parts of the world, thus the use of piles or ‘micropiles’ is extensive in these areas, including Cordoba, Argentina. These foundations could be used as ‘energy piles’ in GSHP systems, with a minimal additional cost. This paper presents a case study of a representative real building in Cordoba where foundations are also used as GHEs. The thermal properties of local soils were experimentally measured and used in detailed state-of-the-art finite element models. Results from the realistic simulations show that the partial substitution of electrical heating and cooling systems with geothermal systems could significantly reduce energy consumption and the size of associated infrastructure, despite the relatively low thermal conductivity of loess. Moreover, accounting for natural surface thermal recharge, which is routinely ignored in GHE design, increases the ability of the energy piles to supply energy to the heat pumps. This case study shows the potential of GSHP technology in a local environment well suited for it and gives incentives to geotechnical engineers to start considering the technology in their designs and practices, even in loess.
Shear Strength of Waste-Wood Biochar and Biochar-Amended Soil Used for Sustainable Landfill Cover Systems
Authors: Sadasivam Bala Yamini  , Reddy Krishna R.
Published: February 2025

In this study, soil, biochar and 10% biochar-amended soil (by weight) were tested for their shear strength properties under dry and moist (15% moisture by weight) conditions in order to compare and analyze the variations in their shear strength parameters. Pelleted biochar derived from gasification of waste hardwood, and silty clay soil obtained from an intermediate cover area of a landfill site were used in this study. Several series of direct shear tests were conducted under different normal stresses ranging from 0 to100 kPa to simulate typical vertical stress conditions expected under a field scenario for landfill cover during and after construction. The results of direct shear testing were used to calculate shear strength parameters (cohesion and angle of internal friction) upon plotting the Mohr-Coulomb failure envelopes for different materials tested. The addition of biochar to soil dramatically increased the cohesive strength of moist soil by almost three times. The shear strength values of biochar was comparatively higher than that of soil indicating that the addition of biochar to cover soil can improve the overall stability of landfill covers.
Numerical Simulations of Crosshole and Downhole Seismic Measurements as Quality Control Tool for Jet Grout Columns
Authors: Galindo Guerreros J.C.  , Mackens S.  , Niederleithinger E.  , Fechner Th.
Published: February 2025

Sealing and strengthening of the subsoil by injection is a major issue in the field of geotechnical engineering. This involves also jet grouting, which allows creating columns of grouted soil by eroding and mixing the in-situ soil with a thin cement suspension. A general difficulty of this method is to predict the column diameter and its material strength. Here, we present two-dimensional finite-difference numerical simulation results of a promising non-destructive quality assurance testing tool to evaluate the diameter of jet grout columns. This approach incorporates crosshole and downhole seismic measurements. Preliminary tests showed that this tool is applicable under real site conditions.