bluuebunny/crossref_metadata_2025 huggingface dataset:
A conceptual framework related to ICT-AT competence development: The theoretical foundations of ENTELIS
Authors: Mavrou Katerina  , Hoogerwerf Evert-Jan  , Meletiou-Mavrotheris Maria  , Kärki Anne  , Sallinen Merja
Published: February 2025

This paper provides an overview of the construction of a conceptual framework regarding ICT-Assistive Technology (ICT-AT) competence development, designed to gain awareness of the elements involved and to facilitate the understanding and exchange among stakeholders of the ENTELIS (European Network for Technology Enhanced Learning in an Inclusive Society) project. The framework was designed based on the basic principles of Activity Theory, which however have been adapted and adjusted to the project's objectives. Hence, it includes a map of actors and other parameters functioning in a person surrounding “ecosystem”, and it allows us to understand and map roles, expectations, barriers, as well as to devise solutions to tackle digital divide. Taking as a starting and central point the person and his/her wish to self-determination and fulfilment (quality of life) and the related needs, it provides a map of how the various concepts and variables interact within the theoretical and methodological perspective of the collection, description and assessment of experiences in ICT-AT education and competences development of persons with disabilities (PwD) of all ages. The conceptual framework represents two interacting learning activity systems: (a) the internal system of the end-user, which includes the end-user and his/her needs, the setting where learning takes place and the other actors involved, and (b) the external system, which embraces the internal system but also wider issues of policy and practice and experiences and ‘actors’ that contribute to the development and use of ICT and ICT-AT skills in all areas of life. The elements of these systems and their interaction provide the basis for analysing experiences and advancing knowledge relevant for bridging the digital divide.
A Unified Semantic Framework for the description of assistive technologies
Authors: Konstadinidou Aggeliki  , Kaklanis Nikolaos  , Votis Konstantinos  , Tzovaras Dimitrios
Published: February 2025

This paper presents the Semantic Alignment Tool, a unified, classified, ontological framework, for the description of assistive solutions that comprises information from different sources automatically. The Semantic Alignment Tool is a component of the Cloud4All/GPII infrastructure that enables users to add and/or modify descriptions of assistive technologies and align their specific settings with similar settings in an ontological model based on ISO 9999. The current work presents the interaction of the Semantic Alignment Tool with external sources that contain descriptions and metadata for Assistive Technologies (ATs) in order to achieve their synchronization in the same semantic model.
Developing movement recognition application with the use of Shimmer sensor and Microsoft Kinect sensor
Authors: Guzsvinecz Tibor  , Szucs Veronika  , Sik Lányi Cecília
Published: February 2025

Nowadays the development of virtual reality-based application is one of the most dynamically growing areas. These applications have a wide user base, more and more devices which are providing several kinds of user interactions and are available on the market. In the applications where the not-handheld devices are not necessary, the potential is that these can be used in educational, entertainment and rehabilitation applications. The purpose of this paper is to examine the precision and the efficiency of the not-handheld devices with user interaction in the virtual reality-based applications. The first task of the developed application is to support the rehabilitation process of stroke patients in their homes. A newly developed application will be introduced in this paper, which uses the two popular devices, the Shimmer sensor and the Microsoft Kinect sensor. To identify and to validate the actions of the user these sensors are working together in parallel mode. For the problem solving, the application is available to record an educational pattern, and then the software compares this pattern to the action of the user. The goal of the current research is to examine the extent of the difference in the recognition of the gestures, how precisely the two sensors are identifying the predefined actions. This could affect the rehabilitation process of the stroke patients and influence the efficiency of the rehabilitation. This application was developed in C# programming language and uses the original Shimmer connecting application as a base. During the working of this application it is possible to teach five-five different movements with the use of the Shimmer and the Microsoft Kinect sensors. The application can recognize these actions at any later time. This application uses a file-based database and the runtime memory of the application to store the saved data in order to reach the actions easier. The conclusion is that much more precise data were collected from the Microsoft Kinect sensor than the Shimmer sensors.
Daily activity patterns of people provided with a dynamic arm support
Authors: van der Heide Loek A.  , de Witte Luc P.
Published: February 2025

Dynamic arm supports are provided to support activities of daily living in people with limited upper extremity function. A cross-sectional study was performed in the Netherlands involving people who were provided with a dynamic arm support in 2012–2013. An adapted version of the Life-Habits questionnaire was used to assess daily activity patterns. Twenty-three subjects filled in the questionnaire. Tasks people perform themselves in daily life include tasks as eating, drinking, and communication tasks. Participants vary in the need for assistance in order to perform certain tasks. This individual character of daily activity performance is important to bear in mind during the provision of dynamic arm supports. More complex tasks in the field of personal care and household are often performed by caregivers. These are regarded a challenge for the field of assistive technology and/or robotics.
Effectiveness of IPMS tool for handling chronic low back pain with sitting workplace employees
Authors: Maas Hille
Published: February 2025

Effectiveness of IPMS tool for handling chronic low back pain with sitting workplace employees.
A Methodology for Pattern Detection in Gait Behaviour using the i-Walker
Authors: Moreno Jonatan  , Cortés Atia  , Barrué Cristian  , Cortés Ulises
Published: February 2025

Our societies are dealing with the fast increasing of the elderly population and its consequences in terms of public health sustainability. Elderly tends to suffer from different diseases that affect their autonomy. An early detection of risk factors and the correspondent medical intervention could be determinant to maintain the Quality of Life (QoL) of this social group and retrieve part of the economic impact to public health systems. We rely on the hypothesis that some impairments/diseases can affect to the ambulatory skills of the elderly. This paper presents a methodology for detecting common walking patterns in the elderly according to their physical and cognitive conditions that could help to the early risk detection.
Geotechnical Risk Management in Dutch Public Infrastructure Projects
Authors: Brandsen Cees  , Cools Paul M.C.B.M.
Published: February 2025

In the Netherlands more and more attention is paid on reducing geotechnical failures in civil engineering projects. This paper focusses on describing the contractual measures and procedures Rijkswaterstaat as a client has developed and implemented in recent years for this purpose. The principles of Geotechnical Risk Management are leading.
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 litres per second per meter dam, and the effect of this overtopping on the Afsluitdijk is unknown.
Soil Displacement Induced Laterally Loaded Piles Test Embankments Bloemendalerpolder – Geo-Impuls Program
Authors: Schadee L.W.  , Hoefsloot F.J.M.
Published: February 2025

In the Bloemendalerpolder two test embankments were constructed in 2010 to study the long term behaviour of embankments on very soft soils with respect to settlement and lateral pile loading resulting from horizontal soil deformations. A detailed description of the test embankments, performed soil investigation, laboratory tests and instrumentation is given in an accompanying paper. This paper provides a brief description of both test embankments consisting of sandfill with a height of 3.0 m and a ground area 26 × 36 m2with slopes 1:2. At one embankment – overlying 5.7 m of peat/clay – wick drains are installed at a triangular spacing of 1.0 m. The second embankment – overlying 4.0 m of peat/clay – is not provided with any additional drainage accelerating measures. In each embankment two steel H-beam piles have been installed, one located at the crest of the slope and one 4 m from the crest. Both piles have been installed 3 weeks after completion of the final fill increment. The pile bending stiffness represents a prefabricated concrete pile square 0.26 m. The piles were equipped with a steel square guiding tube to perform inclinometer measurements. Inclinometer readings were performed at regular time intervals, each reading at depth intervals of 0.1 m. The small interval was selected to improve interpretation with respect to pile curvature and therefore the derivation of pile bending moments. Although horizontal soil deformations after pile installation are significant the resulting bending moments remain limited.
Role of Soil and Structural Heterogeneity in Geotechnical System Redundancy
Authors: Naghibi Farzaneh  , Fenton Gordon A.
Published: February 2025

It is well known that redundancy generally improves system reliability. For example, a geotechnical support system comprised of a single monopile will have the same failure probability as the monopile itself. Alternatively, if the geotechnical support system is comprised of two piles, each of which can support the load with probability 1−pf, then the system failure probability will lie somewhere between pfand p2f. In this case, if the failure probability of an individual pile is pf=1/100, then the system failure probability will lie between 1/100 and 1/10,000, depending on the degree of statistical dependence between the piles. Clearly, redundancy in the geotechnical system has the potential to significantly reduce the system failure probability. From a design point of view, since redundancy generally increases system reliability, the individual system elements (e.g., piles) need not necessarily be designed to the same level of reliability. In other words, if the supported load is distributed amongst a number of footings or piles, redundancy should be taken into account to achieve construction savings while maintaining overall safety. This paper looks specifically at the effects of redundancy in pile support systems on the overall system reliability. It is assumed that the support only fails when all piles have failed and piles fail randomly according to the local ground strength (pile structural capacity is not considered). Two load transfer models between failed (excessively displaced) and surviving piles are considered. Pile system reliability is then estimated as a function of the distribution of pile resistance, the load transfer model, the number of piles, and the target design reliability of individual piles. Charts are produced to allow the selection of individual target design reliability for a given number of piles and the target system reliability.
Presenting Uncertainty Clearly: Challenges In Communicating Geotechnical Risk
Authors: Sartain Nick  , Mian Juliet  , Free Matthew
Published: February 2025

This paper provides recommended guidelines for communicating geotechnical risk. Geotechnical engineering in practice is the management of ground-related risks, and geotechnical engineers are good at this. However, they are often less good at communicating these risks to stakeholders who may hold very different perceptions of risk. A review of selected good practice in risk communications from other industries is presented along with lessons that are considered to be applicable to communication of geotechnical risk. The authors draw on their extensive experience in communicating geotechnical risk, ranging from public consultation events for controversial ground engineering projects to working with clients with diverse risk tolerance and risk understanding. Clear, inclusive and participatory risk communication and management is considered essential in such cases.
About the Implementation of Geotechnical Risk Management (Geo-RM) in Construction Projects
Authors: van der Schrier Joost  , Hoeber Hans
Published: February 2025

One of the key recommendations of the Geo-Impuls program, which investigated possibilities to complete more construction projects within time and budget, is to anchor geotechnical risk management in an explicit way within the project (risk) management structure. Geo-Impuls acknowledges that this puts specific demands on the project management structure. Virtual Design and Construction (VDC) might provide this structure. The paper discusses the possibilities offered by Virtual Design and Construction (VDC) to anchor geotechnical risk management explicitly within the project management structure.
The Effect Of 3D Audio And Other Audio Techniques On Virtual Reality Experience
Authors: Brinkman Willem-Paul  , Hoekstra Allart R.D.  , van Egmond René
Published: February 2025

Three studies were conducted to examine the effect of audio on people's experience in a virtual world. The first study showed that people could distinguish between mono, stereo, Dolby surround and 3D audio of a wasp. The second study found significant effects for audio techniques on people's self-reported anxiety, presence, and spatial perception. The third study found that adding sound to a visual virtual world had a significant effect on people's experience (including heart rate), while it found no difference in experience between stereo and 3D audio.
Equivalent interface properties to model soil-facing interactions with zero-thickness and continuum element methodologies
Authors: Damians Ivan P.  , Yu Yan  , Lloret Antonio  , Bathurst Richard J.  , Josa Alejandro
Published: February 2025

Soil-facing mechanical interactions play an important role in the behavior of earth retaining walls. Generally, numerical analysis of earth retaining structures requires the use of interface elements between dissimilar component materials to model soil-structure interactions and to capture the transfer of normal and shear stresses through these discontinuities. In the finite element method PLAXIS software program, soil-structure interactions can be modelled using “zero-thickness” interface elements between the soil and structural components. These elements use a strength/stiffness reduction factor that is applied to the soil adjacent to the interface. However, in some numerical codes where the zero-thickness elements (or other similar special interface elements) are not provided, the use of continuum elements to model soil-structure interactions is the only option. The continuum element approach allows more control of the interface features (i.e., material strength and stiffness properties) as well as the element sizes and shapes at the interfaces. This paper proposes parameter values for zero-thickness elements that will give the same numerical outcomes as those using continuum elements in PLAXIS. The numerical results show good agreement for the computed loads transferred from soil to structure using both methods (i.e., zero-thickness elements and continuum elements at interfaces).
Contribuciones para la rehabilitación de cimentaciones superficiales con pilotes auto-perforante en suelo tropical
Authors: Mendoza Cristhian C.  , Da Cunha Renato Pinto  , Barbosa Max  , Caicedo Bernardo
Published: February 2025

Aún en la práctica de rehabilitación de fundaciones no se sabe cuál es el aporte de la zapata pre-existente a la rehabilitación. Además, se cuenta con gran variedad de tipos de micropilotes para ser usados en labores de rehabilitación de fundaciones. En este trabajo se propone el uso del micropilote tipo “Alluvial Anker” para rehabilitación de estructuras, sabiendo que en la actualidad este carece de estudios realizados en su comportamiento a nivel académico. Para realizar lo anterior se ejecutaron pruebas de carga con diferentes tipos de configuraciones de sistemas placa-pilote a escala real con y sin aporte de la zapata, en un campo experimental construido. Posteriormente, se realizan simulaciones de estas pruebas en elementos finitos con un modelo elasto-plástico. Como resultados se obtiene el aporte de la zapata existente al nuevo sistema integrado, después de la rehabilitación de la estructura existente, además se obtienen los porcentajes de distribución de la carga en cada una de las partes del sistema placa-pilote para cada una de las configuraciones utilizadas.
Investigation of Mechanical Properties of Fibre-Reinforced Grouts for Micropile Application
Authors: Abdlrahem Maged  , El Naggar M. Hesham
Published: February 2025

Micropiles are used to enhance the capacity of existing foundations and to support a lightly loaded new structure. Recently, there is an interest in using micropiles to support heavy structures due to their advantages related to constructability, even in remote and restricted access sites, ground improvement effects and economic efficiency. In particular, hollow bar micropile (HBMP) is a promising technique, which can carry a considerable amount of axial loads. However, due to their small diameter, micropiles lateral capacity is limited, which restricts their use in applications that impose large lateral loading on the foundation.
Effect of intermittent wetting on the UCS of lime-treated expansive soils
Authors: Elkady Tamer  , Shaker Abdullah  , Baig Arif A.  , Al-Shamrani Mosleh
Published: February 2025

Laboratory determination of design lime content to be applied in the field involve preparing soil-lime specimens with different lime contents to evaluate their swelling potential and unconfined compressive strength (UCS) after curing for 7 or 28 days. Curing of specimens is typically conducted under the conditions of ambient temperature and relative humidity greater than 95%. During field application, lime-treated expansive soils may be subjected to cases of increase moisture. This paper investigates the effect of wetting during curing period on the UCS of lime-treated expansive clay. An experimental program was devised where lime-treated specimens were subjected to different wetting schemes (whether a single wetting event or multiple wetting events) and the UCS at the end of the curing period is evaluated. Other parameters investigated included lime content (2%, 4% and 6% on dry weight basis) and curing period (7, 14 and 28 days). Results of the tests indicated that wetting schemes had a detrimental effect on the UCS of lime-treated specimens; especially at low lime content (i.e., 2%). Furthermore, as the lime content increased, the percentage reduction in UCS decreased.
Evaluation of excess pore pressures around piles driven into clayey soils
Authors: Silva Pedro C.R.  , Massad Faiçal  , Bilfinger Werner
Published: February 2025

In many cases, excess pore pressures generated during pile driving into clayey soils lead to a decrease in the effective stresses around the pile, thus facilitating the driving process. The dissipation of these pore pressures can be considered as the main mechanism that explains the occurrence of gains in load capacity of piles with time, known as set-up. This article shows the results of tests conducted on piles at 3 construction sites located on the Brazilian coast, which indicate the occurrence of important gains in load capacity over time. The results shown are assessed through analytical solutions and from field studies that permit some evaluation of the excess pore pressures generated around driven piles into clayey soils.
Comparative analysis of analytical and numerical calculation methods for soil improvement by rigid inclusions
Authors: Pérez Rodrigo Gómez  , Melentijevic Svetlana
Published: February 2025

In recent decades a soil improvement technique of foundation soft soils by inserting or constructing rigid inclusions has been developed. Its main application is in compressible soils under large fills or foundations of structures, optimizing the construction time and decreasing settlements considerably. Along with the development of the method, various codes and standards in different countries in Europe have been published as guidelines for analysis of rigid inclusions and different elements that make up the technique such as load transfer platform, etc. Considering the increased use of finite element modelling in different geotechnical problems, in this paper a comparison of analytical and numerical calculation methods of rigid inclusions is presented. Load transfer platform is analyzed for its different thicknesses and various separations between inclusions that defines the ranges in which analytical methods approach numerical modelling. The interaction between the soft soil and rigid inclusion for estimating ground settlements is also studied. Considering different soil stiffness, the comparison of settlements obtained by analytical and numerical methods has been done. Furthermore an analysis of the variation of the neutral point depth with the change of soft soil stiffness is performed by finite elements. This depth is decisive in the calculation of the total length of the rigid inclusion.
Análisis de la estabilidad de perforaciones para pilas
Authors: Paniagua Z. Walter I.  , Hernández G. Cecilia
Published: February 2025

En este articulo se presenta una descripción de herramientas analíticas desarrolladas por diversos autores para el análisis de la estabilidad de perforaciones para pilas: estabilidad de las paredes con lodo bentonítico, estabilidad de las paredes con ademe y estabilidad del fondo de la perforación. Se revisan las ventajas del método así como sus limitaciones y se presentan ejemplos de aplicación de esta problemática.
New device for experimental determination of the soil-water retention surface
Authors: Quaglia Gastón  , Plaisted Michael  , Zornberg Jorge
Published: February 2025

While it has been recognized that the soil-water retention properties are affected by the soil void ratio, standard test methods for determination of soil-water retention curves do not account for soil volume changes, assuming a condition of constant volume. However, significant volumetric changes are expected when characterizing highly plastic soils, even for comparatively small changes in water content. This paper presents a new testing device that allows continuous measurement of three relevant variables: void ratio, matric suction, and water content. This set up is used along wetting paths in order to determine the soil-water retention surface. The set up allows continuous measurements of the relevant variables by using displacement sensors and a scale system. The new equipment is described in detail, and a set of tests results are presented in order to show its capabilities. The results indicate that, rather than a characteristic soil water retention curve, the new device can be successfully used to characterize a soil water retention surface defined by matric suction, water content, and void ratio [ψ,w,e].
Estabilización de Suelos Blandos con Geosintéticos
Authors: Moreno Carlos  , Perez Sandra  , Sifuentes Nestor
Published: February 2025

La estabilización de Suelos blandos saturados, es uno de los desafíos más importantes de la ingeniería civil, especialmente en la construcción de cualquier tipo de infraestructura vial. América Latina se caracteriza por la presencia de suelos tropicales, con altos grados de meteorización y presencia excesiva de humedad, que derivan en bajas resistencias al corte, no aptas para la cimentación de estructuras. Mediante el uso de geosintéticos, es posible la estabilización de suelos blandos, logrando plataformas de trabajo y niveles aceptables de reacción a nivel de subrasante para la conformación de vías. En el presente documento se resumen algunos proyectos desarrollados con éxito en el continente.
Recent trends for design of filters in earth and rockfill dams, including geotextiles criteria
Authors: López-Acosta Norma Patricia  , Guillén Jorge Bricio  , Auvinet Gabriel
Published: February 2025

The purpose of the filters employed as seepage control measures in earth structures is to efficiently control the movement of the water in and out of them. In order to satisfy this objective the filters must (during the useful life of the project and with a proper maintenance) retain the protected materials, have a higher permeability than the protected soil and have sufficient discharge capacity. In this paper, an overview of the most recent trends for design of granular filters in earth and rockfill dams is provided. The current methods not only respect the basic principles of retention and permeability enunciated by Terzaghi (1922), but additionally suggest guidelines to follow more systematic and particular purposes for the function of a filter, mainly focusing attention on the design rules, and also in quality control during construction. Initially the classical methods for design of granular filters are briefly reviewed. Subsequently, the procedures of principal design criteria currently used: USSCS (1994), USACE (2004) and USBR (2011) are described with the help of flow charts. The applicability of recent and classical filter design methods for materials of different earth structures, including the soil categories that consider the current criteria, is demonstrated by examples. The resulting filter bandwidths obtained by the diverse methods are compared. The most important rules for the design of geotextiles used as filters for dams are also exposed: permeability, retention, porosity and thickness criteria. Finally, conclusions and recommendations are given.
Caracterización de Concretos Asfálticos Elaborados con Residuos de Demolición y Construcción (RCD)
Authors: Ossa Alexandra  , García José Luis
Published: February 2025

En esta investigación se estudia la alternativa de utilizar agregados producto del reciclado de residuos de construcción y demolición (RCD) en la elaboración de mezclas asfálticas en caliente. Se utiliza la metodología SUPERPAVE para el diseño de mezclas asfálticas así como el protocolo de la Asociación Mexicana del Asfalto (AMAAC). Para acelerar el proceso de diseño de las mezclas se utiliza el método de RAMCODES también conocido con método del polígono de vacíos. Los resultados obtenidos indican que es factible utilizar porciones de RCD en la construcción de carpetas asfálticas para vías urbana.
Automatic learning for patterning the behavior of rockfill materials
Authors: Garcia Silvia  , Romo Miguel  , López-Molina Jorge
Published: February 2025

In order to deal with the ill-posed problem of material parameter identification for rockfill materials, a procedure based on machine learning is proposed. In this investigation the results of a comprehensive set of tests on rockfill materials are examined. The instances, categorized in accordance with their particles shape (angular / rounded), gradation characteristics and relative density, are analyzed using Regression Trees, a machine learning tool that deals with the construction and study of algorithms for learning from data. The emphasis of this study is on determining resistance and deformability behavior of the rockfill. It is shown that high confining stresses and particle breakage phenomenon are found as the driving factors of the behavior of the materials.
Influence of mineralogy and microstructure on the mechanical behavior of a gneissic residual soil
Authors: Cecílio Jr. Marlísio Oliveira  , Futai Marcos Massao
Published: February 2025

Undisturbed samples were collected from the heading of a tunnel excavation, from a ground characterized as gneissic saprolitic residual soil. By the collecting time, the tunnel was under construction for the Line 4-Yellow of Sao Paulo subway network. The soil mineralogical composition is presented, as well as a microscopic analysis which identifies some of its minerals and exposes its microstructure. Oedometer and triaxial tests were also carried out with these samples, aiming to study the soil mechanical behavior by means of compressibility, stress-strain relations, yielding envelope and shear strength.
Free Surface Effects for Ground Vibration and Effective Burden by using Abrasive Waterjet System
Authors: Joo G.W.  , Oh T.M.  , Cho G.C.
Published: February 2025

Major metropolitan areas increasingly require the construction of underground spaces such as tunnels for the effective use of limited urban land. Blasting is used world-wide for rock excavation because of its cost and excavation efficiency. However, modem urban rock excavation requires low vibration and rapid excavation. In this study, an in-situ experimental test was performed to verify the effects of free surface on these factors. A continuous free surface was generated with different burden using abrasive waterjet cutting technology along the perimeter of a target tunnel face. Then, blasting was conducted along the projected excavation line (i.e., the tunnel perimeter). Blasting-induced vibration was measured at ground level using geophones and the vibration results were compared with those from a conventional blasting method. In addition, over-break and under-break levels were measured and analyzed in order to optimize the effective burden under a free surface condition. This alternative blasting method with an artificial free surface resulted in reduced vibration and increased burden versus conventional blasting. The method can also reduce the number of holes drilled for explosive charges and the total weight of explosives needed.
Site Response Analysis for Seismic Design for Regional Connector Transit Corridor Project in Los Angeles, California
Authors: Chaudhuri Debanik  , Hudson Martin B.  , Choi S.H. Jason  , Hansmire William H.
Published: February 2025

The Regional Connector Transit Corridor (RCTC) Project is a 3-km (1.86 mile) underground light rail project in downtown Los Angeles, California being constructed by the Los Angeles County Metropolitan Transportation Authority (Metro). In addition to twin bored tunnels, the project will include 789-m (2,590-ft) long concrete box tunnels and three underground stations to be constructed by cut-and-cover construction. These underground structures will be buried within Holocene- to late Pleistocene-age alluvial soils and the Pliocene-age weak clayey siltstone or silty claystone of the Fernando Formation. The deepest station is about 32-m (105-ft) below the existing grade. Located in one of the most active seismic regions of the world, these underground box structures are being designed to withstand seismic loading resulting from vertically propagating seismic waves. Specifically, the box structures will be designed to withstand differential lateral movement (racking) resulting from the shear waves. As part of the preliminary engineering of the project, seismic analyses were undertaken. The analytical procedure and the results are presented demonstrating the current state of practice for seismic design of transit stations and box structures in Los Angeles. The analytical approach followed Metro's design guidelines. Design response spectra and earthquake time histories were developed for two risk levels using Probabilistic Seismic Hazard Analysis (PSHA) and spectral matching. A series of one-dimensional site response analyses were performed to develop a non-linear distribution of free-field displacement along the depth of each underground structure. The results, including time histories of free-field shear strains and horizontal ground displacements during the seismic events for the two risk levels, were used as input parameters to racking analyses to be used in structural response computations.
Large Scale Laboratory Testing to Evaluate Axial Load Capacity of Sheet Piles for Bridge Abutments
Authors: Sylvain Matthew B.  , Pando Miguel A.  , Whelan Matthew J.  , Ogunro Vincent O.  , Park Youngjin  , Koch Thomas
Published: February 2025

This paper presents the results of a full scale, axial load test program carried out on two well instrumented steel sheet pile walls. Traditionally in the U.S., sheet piles are used in bridge abutments to defend bridge abutments against erosion and scour which is often an important design consideration for bridges located near rivers and streams. In this design approach, the axial loads from the bridge superstructure are considered to be supported primarily by deep foundations typically installed behind the scour protection sheet piles. This design approach, although practical, is usually also very conservative. In contrast, short span bridges have been reported as successfully built with steel sheet piles as the main vertical load bearing element in the bridge abutments in several European countries. Despite these reported positive case histories, the axial load contribution from abutment sheet piles is still routinely neglected in design assumptions by U.S. highway agencies. One of the main issues hindering the inclusion of any axial load capacity contribution from these elements is a scarcity of well documented full scale axial load tests on instrumented sheet piles. This paper presents experimental results of axial load tests of sheet piles carried out in a large geotechnical test pit at the Energy Production and Infrastructure Center (EPIC) at University of North Carolina at Charlotte (UNC Charlotte). These results provide experimental evidence that sheet pile elements have great potential to be used as the main axial load bearing foundation element in short span bridges.
Stochastic Solution to the Subgrade Resilient Modulus: Monte Carlo Approach
Authors: Rosenbalm Daniel C.  , Zapata Claudia E.
Published: February 2025

The AASHTOware pavement design procedure is based on a hierarchical approach where a greater number of input parameters are determined by laboratory testing when the magnitude, cost and importance of the project increase. The characterization of unbound materials is accomplished by the estimation of the resilient modulus based on either laboratory measurements (Level 1), correlations with other properties (Level 2), or values based on local experience (Level 3). The procedure makes use of deterministic solutions which are difficult to interpret due to the lack of information related to the compound variability associated with soil heterogeneity and environmental conditions. This document presents a general framework for a stochastic solution to estimate the equilibrium resilient modulus of unbound materials based on the Monte Carlo simulation using the Beta distribution. To illustrate the practicality of the stochastic approach, the document presents a comparison of the results when different hierarchical levels of analysis are used. The analysis presented is fundamental in any decision-making stage within the design and construction control of projects and can easily be adapted to other civil infrastructure analysis.
Geosynthetic Reinforcement of Buried Flexible Pipes
Authors: Clariá Juán José  , Moreno Guillén Francis Morella
Published: February 2025

Buried pipes perform a key role in urban centers, including multiple functions from fluid transport to electric lines conduction. Usually, flexible pipes design is developed by means of approximate formulations derived from the elasticity theory (v.g. Spangler Iowa). Although there are many studies about the interaction between a soil and a buried pipe, several failures are observed in these systems. In order to reduce the pipe deflections and stresses, the system reinforcement with a geosyntethic is proposed. The present paper shows the results of a parametric study about the interaction between a flexible buried pipe (e.g. polyester reinforced with fiberglass pipe – PRFV) with the surrounding soil and a geosynthetic acting as a reinforcement element. For the analysis of the soil-pipe-geosynthetic interaction and behavior, a bidimensional finite element model was built using PLAXIS software. By means of the numeric model, the contribution of the geosynthetic as a function of the soil and pipe stiffness was determined. The influence of the geosynthetic burial depth on the pipe deflection is also analyzed. The maximum geosynthetic contribution is observed for the case of pipe trenches excavated on rigid natural soils backfilled with softly compacted materials in order to avoid pipe damage.
Uso del Sistema de Clasificación de Terreno para British Columbia para el mapeo geológico-geotécnico de superficie en obras civiles
Authors: Jara Gonzalo  , Sierra Carlos
Published: February 2025

Como parte de la información base que se genera en las distintas etapas de un proyecto de ingeniería asociado a la construcción de una obra civil, se encuentra el mapeo geológico-geotécnico de superficie. Especificar las características del terreno y mostrar su distribución en el área de estudio, resultan fundamentales al momento de ejecutar una obra civil. La utilización, aplicación y adaptación del Sistema de Clasificación de Terreno para British Columbia (SCTBC) permite caracterizar un área determinada, clasificando materiales superficiales, su textura, expresiones superficiales, procesos geomorfológicos y tipos litológicos, que proporcionan información geológico-geotécnica de interés para el diseño de ingeniería de una obra civil. El mapa geológico-geotécnico basado en el SCTBC constituye una herramienta que entrega mayor cantidad de información y de mejor calidad que el mapeo geológico de superficie convencional, aportando incluso en la identificación de zonas de peligros naturales de índole geológica y aprovechando aún más el trabajo que se realiza en campo. El presente artículo muestra el desarrollo que ha aplicado Golder Associates en sus proyectos, mediante el uso del sistema SCTBC.
New Capacitive Sensor for In-situ Soil Moisture Estimation
Authors: Orangi Amir  , Narsilio Guillermo A.
Published: February 2025

Moisture content and density play important roles in many industries and applications. These parameters must be determined rather frequently in the construction industry particularly in road construction, in environmental studies and generally in soil investigations. In practice, these are primarily estimated through various invasive methods, derived from time-consuming and labour-intensive soil sampling. Alternatively, nuclear probes – which are hazardous, expensive to maintain and require a well-trained user to operate – are also being used in this context. However, due to their drawbacks especially the risk to human health and rigorous user certificate requirements, there exists an ongoing need for further alternatives. The substantial cost associated with in-situ methods of soil investigation is an additional driver for the need to develop more cost effective methods. Focusing on moisture content first, this experimental investigation proved the potential of a new, fast and cost effective capacitance-based sensor to measure the in-situ soil moisture content non-invasively, through measurement of the soil electrical properties from the ground surface.
Estudo da Correlação Entre os Ensaios Sondagem a Percussão (SPT) e Penetrômetro Portátil Barra Mina (BM)
Authors: Arcanjo Daniele  , Ramos Viviane  , Marques Juliane
Published: February 2025

Esse trabalho tem como objetivo estabelecer correlaçães entre os ensaios de Sondagem a Percussão (SPT) e o Penetrômetro Portátil do tipo Barra Mina (BM). Foram realizadas diversas campanhas de ensaios buscando-se ampliar o banco de dados das sondagens com SPT e BM, obtendo mais dados para as correlações entre os ensaios e assim aumentando a confiabilidade da aplicação do ensaio BM. As correlações entre os ensaios foram realizadas através de estudos das resistências a penetração do ensaio SPT (NSPT) e do ensaio Barra Mina (N10). Para cada sondagem SPT e BM foram obtidos pontos correlacionáveis através de um ajuste linear, permitindo-se definir equações de correlação e seu respectivo coeficiente de correlação (R2). Os resultados das correlações dos ensaios SPT e BM foram agrupados por tipo de solo, definindo-se correlações para os solos arenosos e argilosos.
Runoff Behavior of Pervious Sidewalk Block
Authors: Seo Dawa  , Sup Yun Tae  , Soo Youm Kwang
Published: February 2025

This study presents experimental results of evaporation and drainage responses to the rainfall simulation for pervious sidewalk blocks. Two representative specimens made of designated size of aggregates are tested. The commercially acceptable coarse aggregates are served as substratum of the block with additional surface layer. The specimen without surface layer is made to solely assess the effect of each layer. The water-charge intensity higher than normal rainfall intensity is decided to emulate the urban condition where the overflowing water highly prevails. As the water-charge does not necessarily impose the full saturation of pervious block and evaporation takes place, the repeated water-charge at four different time steps is scheduled and the volumes of drainage and runoff are concurrently monitored. The evaporation and 3D X-ray computed tomographic imaging help evaluating time-dependent evolution of drainage capacity of tested pervious blocks. Results highlight that the small pore of surface layer affects the drainage behaviors and capacity. The surface layer reduces the rate of evaporation due to the smaller exposed pore areas of surface than substratum. Capillary force in surface layer causes large runoff volume and keeps high degree of saturation. This experimental observation of drainage capacity provides the central insights to design the pervious block whose hydraulic behaviors are ensured for sufficient drainage in urban areas.
Temperature Effects on Surface Texture of Geomembranes
Authors: Yesiller Nazli  , Manheim Derek  , Hanson James  , Kopp Kevin  , Fiegel Gregg
Published: February 2025

A laboratory investigation was conducted to characterize surface features of textured geomembranes as a function of temperature using white light optical interferometry. Five types of HDPE geomembranes from different manufacturers were tested. The textured geomembranes included cast-extruded, co-extruded, and impinged products. Specimens were heated and cooled using a thermal stage attachment for the interferometer. Tests were conducted between 2 and 100°C. Amplitude and spatial texture parameters were determined. 3D images of the specimens and summary of parameters are included in the paper. Variations were observed in surface texture characteristics due to heating or cooling of the specimens. The decrease in the magnitude of the majority of texture parameters at 100°C indicated the presence of a thermal threshold, where surface texture features were affected on the macroscale. The thermal effects on the co-extruded materials in general were lower than the effects on the cast-extruded material. The changes to the surface texture characteristics have potential effects on the engineering response of the textured geomembranes.
Evaluación de riesgos por caída de rocas en laderas; metodología utilizada en Centrales Hidroeléctricas de México
Authors: Montiel Edgar  , Escamilla Francisco  , Zúñiga Javier  , Fernández Ana
Published: February 2025

A partir de las problemáticas causadas por la cercanía de algunas obras de generación y distribución de energía con respecto a las laderas naturales en México, ha sido necesario establecer metodologías que permitan evaluar los riesgos a los que podrían estar expuestas dichas obras. Con el objetivo de mostrar una metodología seguida para evaluar diversas condiciones desfavorables, en este documento se muestra una propuesta que se ha ido aplicando en México, cuyos resultados han permitido establecer racionalmente medidas de mitigación que brinden protección a dichas obras ante los procesos naturales de degradación de laderas.
The Influence of Open and Closed Toe Notches on the Stability of Rock and Soil Slopes
Authors: Vallejo Luis E.
Published: February 2025

This study involves the influence on slope stability of notches located at the toe of rock and soil slopes. A notch could be open or closed. An open notch is a cut made at the toe of a slope as a result of wave action. A closed notch is a discontinuity at the toe of a slope resulting from the stress release taking place when a cut with a sloping face is made in a layer of rock. Open and closed notches can propagate as a result of gravity induced stresses inside the slopes. Using the principles of Linear Elastic Fracture Mechanics theory, it was determined that that the notch act as stress concentrator. Since the gravity induced stresses are the higher at the tip of a notch, the failure of the slope will start at the tip of the notch. The angle of propagation, α, of the secondary cracks emanating from the tip of an open or closed notch can be obtained from the following relationship: sin α+(τ/σn)(3cos α−1)=0. In this equation, τ is the gravity shear stress parallel to the longitudinal axis of the notch, and σnis the gravity stress normal to the axis of the notch. The measured and calculated value of α using this equation compared very well for both open and closed notches developed by slopes in the field and laboratory.
Using Gamification Combined with Indoor Location to Improve Nurses' Hand Hygiene Compliance in an ICU Ward
Authors: Lapão Luís Velez  , Marques Rita  , Gregório João  , Pinheiro Fernando  , Póvoa Pedro  , Mira da Silva Miguel
Published: February 2025

Healthcare acquired infections are among the biggest unsolved problems in healthcare, implying an increasing number of deaths, extra-days of hospital stay and hospital costs. Performing hand hygiene is a simple and inexpensive prevention measure, but healthcare workers compliance with it is still far from optimal. Recognized hurdles are lack of time, forgetfulness, wrong technique and lack of motivation. This study aims at exploring gamification to promote nurses' HH compliance self-awareness and action. Real-time data collected from an indoor location system will provide feedback information to a group of nurses working in an ICU ward. In this paper both the research's motivation and methods is presented, along with the first round of results and its discussion.