bluuebunny/crossref_metadata_2025 huggingface dataset:
Physics-Based Distributed Collaborative Design for Aerospace Vehicle Development and Technology Assessment
Authors: Kolonay Raymond M.
Published: February 2025

One of the missions of the United States Air Force Research Lab (AFRL) is to develop and assess technologies for next generation aerospace systems. Currently, the assessment is achieved using empirical relationships and historical data associated with systems developed previously. The assessment is done in this fashion due to resource constraints on time, personnel, and funding. Performing technology assessment in such a fashion, although timely, is not necessarily accurate. This is due to the fact that many of the technologies and system configurations being evaluated have no historical or empirical information associated with them. Hence, traditional assessment techniques produce misleading results and subsequently ill-informed decisions by Air Force leadership associated with technology investment and potential future system capabilities. To address this issue the Multidisciplinary Science and Technology Center within AFRL's Aerospace Systems Directorate is developing physics-based design exploration and technology assessment methods and processes. The new methods and processes utilize physics-based analyses and a distributed collaborative computational environment to predict vehicle performance which in turn is used in mission level simulations to assess the impact of a given configuration or technology on the combat effectiveness of a system. The new methods and processes will be executable within the same time and resource constraints of the traditional process. This enables AFRL technology developers to have a quantifiable and traceable trail of the impact of their technologies on system performance parameters such as weight, lift, and drag into terms that Air Force leadership measures system effectiveness – lethality, survivability, sustainability, and affordability. This leads to well informed decisions concerning technology investment and achievable capabilities.
A Modelica-Based Modeling, Simulation and Knowledge Sharing Web Platform
Authors: Wan Li  , Wang Chao  , Xiong Tifan  , Liu Qinghua
Published: February 2025

In order to adapt to the changes brought by mobile office, reduce the initial cost of modeling and simulation, share knowledge resources, and finally attract more customers by platform-community effect formed, the WebMWorks is presented in this paper. Deployed on cloud-computing platform, it provides user a low cost Modelica-based modeling, simulation and knowledge library sharing service of multi-domain physical system. It is based on Web, supporting multi-tenant, collaborative design, textual and visual modeling, knowledge publishing, leasing and purchasing, model commenting and communicating between users. Adopting SOA, the basic function components of WebMWorks is packed into stateless service composites, which can be deployed on cloud-computing platform and extended easily. WebMWorks is assembled with these composites, and provides service online through RIA based on browser.
Teaching Urban Morphology in Portugal
Authors: Marat-Mendes Teresa  , Cabrita Amélia  , Oliveira Vítor
Published: February 2025

The main aim of this paper is to describe the way urban morphology can be taught in an academic environment so as to address the consequences of the modern way of life imposed by processes of urban development, while presenting an analysis of Portuguese reality. To do that, this paper is structured in four parts. The first part introduces the present situation of the Portuguese academic reality regarding the teaching of urban morphology, while offering a brief portrayal of the Portuguese institutes of higher education that incorporate the study of urban form, based on their curricula. The second part presents a specific case study while describing how urban form has been studied at ISCTE for the past 17 years, allowing it to be included in the national range of significant knowledge of urban morphology. The third part of this paper goes back to the origins of the actual academic situation, while: i) analysing the introduction of ‘urban morphology’ in the Portuguese academic curricula of architecture, by law 34:607 in 1945; and ii) briefly analysing the Portuguese cultural and political context at the time this law was decreed. The fourth part exposes the role of the 1948 National Congress of Architecture in this process, and finally, the influence of the law in the teaching of urban morphology at Portuguese Architecture courses, but also its implications in urban practice.
Authoring tool for SmartPhone pedagogical content development
Authors: Gerval Jean-Pierre  , Le Ru Yann  , Ghiron Sylvain
Published: February 2025

This paper sets out a software development targeting the design of pedagogical content to be run on SmartPhones. The result is an authoring tool that does not require any software development skill. Teachers can set up easily and quickly content for their students. Experiments took place last year in a Marine Park where more than 200 contents had been developed. It is a web-based system. Server and database implement Linux, Apache, MySQL and PHP. This architecture has come to be known simply as LAMP. On SmartPhone side, HTML5 and JavaScript technologies enable us to target all kind of devices.
Reasoning in Abstract Dialectical Frameworks Using Quantified Boolean Formulas
Authors: Diller Martin  , Wallner Johannes Peter  , Woltran Stefan
Published: February 2025

Abstract dialectical frameworks (ADFs) constitute a recent and powerful generalization of Dung's argumentation frameworks (AFs), where the relationship between the arguments is specified via Boolean formulas. Recent results have shown that this enhancement comes with the price of higher complexity compared to AFs. In fact, acceptance problems in the world of ADFs can be hard even for the third level of the polynomial hierarchy. In order to implement reasoning problems on ADFs, systems for quantified Boolean formulas (QBFs) thus are suitable engines to be employed. In this paper we present QBF encodings on ADF problems generalizing recent work on QBFs for AF labellings. Our encodings not only provide a uniform and modular way of translating reasoning in ADFs to QBFs, but also build the basis for a novel system. We present a prototype implementation for the admissible and preferred semantics and evaluate its performance in comparison with another state-of-the-art tool for ADFs.
‘Datafication’, Transparency, and Good Governance of the Data City
Authors: Powell Alison
Published: February 2025

It is easier than ever to collect data about all kinds of aspects of daily life. This data can have significant value for the people who produce it, but also for corporations and governments. This chapter investigates how this process of ‘datafication’ operates in the space of the city, where globalization and other political-economic pressures have shifted the notion and practice of citizenship. Through an investigation of the concepts of ‘openness’ and ‘transparency’ the chapter highlights some significant shifts in the power relations related to data collection and use, and identifies directions for future research and policy making in this area.
Flexural behavior of RC Beams with local steel – experimental investigation
Authors: Mourad Shehab  , Charif Abdelhamid  , Khan M. Iqbal
Published: February 2025

Steel manufactures are always complying with the minimum code specifications. However in many countries the actual yield strength of the rebars can exceeds its nominal values by a significant factor, depending on the steel manufacturing processes. Such increase in yield strength can have negative effects on the flexural behavior of beams that are designed as tension controlled, and reduce its ductility, an essential property in seismic resisting structures. The present study experimentally investigated the effect of using rebars with yield strength exceeding its nominal values on the flexural behavior of beams. The study indicates that such increase in rebar yield strength needs to be considered in design in order to achieve the desired ductile failure mode of beams.
Condition assessment of a Johannesburg skyscraper
Authors: van Ede Willem F.  , Ekolu Stephen
Published: February 2025

This paper presents a condition assessment conducted on a Johannesburg skyscraper. It had become apparent that concrete spalling occurred in areas of the top 11m of the Southern and Western facades of the reinforced concrete skyscraper constructed in the 1970's. However, the extent of the problem was unknown. The only information available were two photographs showing spalled concrete and severely corroded reinforcement bars. Some literature search pertaining to the structure was conducted after which, visual inspection and mapping of spalled areas and cracks were conducted. This was followed by a cover meter survey, a half-cell potential survey, and the removal of 20 (twenty) cores for laboratory testing. It was found that the typical problems associated with carbonation and insufficient cover resulted in the corrosion of reinforcement which then led to the spalling observed.
Macro vs mesoscale modelling of fracture in concrete beams: size effect and crack openings
Authors: Aissaoui N.  , Ghezali S.  , Matallah M.
Published: February 2025

The size effect in concrete structures is a well-known phenomenon. In the present paper both macro and meso scale approaches were used to numerically investigate the size effect on notched beams under three point bending. The scale effect is investigated on the nominal strength and on the crack openings. For the macroscopic approach, concrete is considered as a monophasic material described by a softening damage law whereas for the mesoscopic approach, concrete is considered as a biphasic material made of two components (the aggregates and the matrix phase). A damage based model is used to describe the behavior of both the aggregates particles and the matrix phase.
Comparison of simple linear regression and multiple linear regression for estimating fuel use and emission rates for excavators
Authors: Fitriani Heni  , Lewis Phil
Published: February 2025

Heavy-duty diesel (HDD) construction equipment consumes a significant amount of fuel and subsequently emits a substantial amount of pollutants into the environment. In most construction activities, HDD construction equipment is the primary source of emissions. The purpose of this paper is to demonstrate the comparative models for estimating fuel use and emission rates for HDD construction equipment specifically excavators. Second by second data were collected from portable emission measurement system (PEMS), containing fuel use and emission rates datasets along with engine performance data from three excavators. Emission pollutants include nitrogen oxides (NOx), hydrocarbons (HC), carbon monoxide (CO), carbon dioxide (CO2), and particulate matter (PM). For each excavator, predictive models were developed using simple linear regression (SLR) and multiple linear regression (MLR). Results yielded that the MLR accounted for the highest percentage of variability in the data compared to SLR based on the values of coefficient of determination (R2) for each model. In order to exhibit the significant impact of which engine data that may affect the emission rates, the variable impact analysis was also conducted.
Durability of mortars and concretes containing scoria-based blended cements
Authors: Alswaidani Aref Mohammad  , Aliyan Samira Dib
Published: February 2025

A lot of reinforced concrete (RC) structures in Syria went out of service after a few years of construction. This was mainly due to reinforcement corrosion or chemical attack on concrete. The use of blended cements is growing rapidly in the construction industry due to economical, ecological and technical benefits. Syria is relatively rich in scoria. In this study, mortar/concrete specimens were produced with seven types of cement: one plain Portland cement (control) and six blended cements with replacement levels ranging from 10 to 35%. Rapid chloride penetration test (RCPT) was carried out according to ASTM C 1202 after two curing times of 28 and 90 days. The effect on the resistance of concrete against damage caused by corrosion of the embedded steel has been investigated using an accelerated corrosion test (ACT) by impressing a constant anodic potential. The variation of current with time and the time to failure of RC specimens were determined at 28 and 90 days curing. The specimens were also monitored periodically. In addition, effects of aggressive acidic environments on mortars were investigated through 100 days of exposure to 5% H2SO4, 10% HCl, 5% HNO3and 10% CH3COOH solutions. Evaluation of sulfate resistance of mortars was also performed by immersing in 5% Na2SO4solution for 52 weeks. Test results reveal that the resistance to chloride penetration of concrete improves substantially with the increase of replacement level, and the concretes containing blended cements, especially CEM II/B-P, exhibited corrosion initiation periods several times longer than the control mix. Moreover, a definite correlation is observed between RCPT and ACT. An increase in scoria addition improves the chemical resistance of mortar, especially in the early days of exposure, whereas after a long period of continuous exposure all specimens show the same behavior against the chemical attack. According to results of sulfate resistance, CEM II/B-P can be used instead of SRPC in sulfate-bearing environments.
Model-based Tooth Segmentation from Dental Panoramic Radiographs
Authors: Wu Chia-Hsiang  , Liu Jia-Kuang  , Tsai Wan-Hua  , Chen Ying-Hui  , Sun Yung-Nien
Published: February 2025

Tooth contour is essential for orthodontic evaluation. In this study, a method for tooth segmentation from dental panoramic radiographs is proposed to assist orthodontists to obtain reliable therapy planning. The proposed method-locates the position of the target tooth, optimizes the scale, translation, and rotation of a tooth model, and deforms the model based on an energy minimization way. Visual inspection, qualitative analysis, and quantitative analysis were used to evaluate the results. The experimental results show that the accuracy of the proposed method is similar to manual delineationby experts.
Self healing biofilms for wood protection
Authors: Filippovych Kateryna  , Huinink Henk  , van der Ven Leo  , Adan Olaf C.G.
Published: February 2025

The protection of wood in order to extend the service life is an important issue nowadays. As an alternative to traditional wood coatings biofilms can be used. It is a living protective coating for the wood surface against UV and bio-degradation that has ability to recover from local damages such as cracks. The aim of the study is to understand the formation of biofilms on oil treated wood and its self healing (SH) properties. The SH concept and hypothesis are presented below.
Reliability Analysis of Shaft Resistance of Axially Loaded Bored Piles
Authors: Park Jae Hyun  , Park Chul Soo  , Chung Moonkyung
Published: February 2025

As part of Load and Resistance Factor Design (LRFD) implementation effort in Korea, reliability levels for side resistance of bored piles socketed in weak rock were evaluated by using bi-directional pile load test results. Bi-directional pile load tests are widely used to predict the load–settlement behavior of large-diameter bored piles. A database of 24 bidirectional load test data sets and soil property tests was compiled from case studies collected from Korea. The resistance bias factors for the three static design equations [O'Neill and Reese (1999), Horvath and Kenney (1979), and Williams et al. (1980)] were calculated by comparing the representative measured bearing capacities defined by Davisson's criterion with the predicted values. Reliability analysis was conducted following the First-Order Reliability Method (FORM) using the statistics of bias factors. The reliability levels of the three shaft resistance equations evaluated from FORM method for safety factors in the range of 2.0-5.0 were in the ranges of 1.15-2.79 for O'Neill & Reese equation, 0.97-2.62 for Horvath and Kenney equation, and 1.73-3.38 for Williams et al. equation, respectively.
Probabilistic Analysis at Ultimate Limit State of Strip Footings Resting on a Spatially Varying Soil Using Subset Simulation Approach
Authors: Thajeel Jawad  , Al-Bittar Tamara  , Ahmed Ashraf  , Soubra Abdul-Hamid
Published: February 2025

The failure probability of geotechnical structures with spatially varying soil properties is generally computed using Monte Carlo simulation (MCS) methodology. This approach is well known to be very time-consuming when dealing with small failure probabilities. One alternative to MCS is the subset simulation approach. This approach was mainly used in the literature in cases where the uncertain parameters are modelled by random variables. In this paper, it is employed in the case where the uncertain parameters are modelled by random fields, because the spatial variability of the soil properties has proven to greatly affect the behavior of geotechnical structures and to induce a significant change in the variability of their responses. This is illustrated through the probabilistic analysis at the ultimate limit state (ULS) of a strip footing resting on a one- and two-layer purely cohesive soil with a spatially varying cohesion. The soil cohesion parameter was modeled as an anisotropic non-Gaussian (log-normal) random field using a square exponential autocorrelation function. The Expansion Optimal Linear Estimation (EOLE) method was used to discretize this random field. The deterministic model was based on numerical simulations using the finite difference software FLAC3D.
Limit-State Design of a Steel Storage Tank Foundation on a Crushed Rock Ring Based on Proven Soil Strength
Authors: Reinders K.J.  , Schoenmaker B.  , Nohl W.A.
Published: February 2025

New steel storage tanks were built at the exact locations of old tanks with identical dimensions, which were erected 50 years ago. The stability calculation for the foundation of the new storage tanks on a crushed rock ring did not fulfil the requirements of the present Eurocode. Presently, steel storage tanks are categorised in Consequence Class 2 or 3 according to Eurocode EN-1990. These Classes did not exist 50 years ago and the old tanks were built with a safety level more or less equal to Consequence Class 1. In order to optimize the design, it was decided to recalculate the stability using state-of-the-art Finite Element Plaxis 2D Software and the code for existing structures “NEN 8707”, which is currently being developed. According to NEN 8700 it is allowed to use a lower value for the reliability index β for existing structures compared to new structures, because of proven strength. Thus, lower partial load and material factors can be applied. Calculations have been performed for the hydro-test phase and the operational phase using undrained and drained soil behavior, taking into account the preloading of the soil. These calculations in combination with NEN8707 resulted in a sufficient overall safety factor for the ultimate limit state. The tanks could be built on a crushed rock ring foundation without an expensive soil improvement.
Detection of Anomalies in Diaphragm Walls
Authors: Spruit Rodriaan  , van Tol Frits  , Broere Wout
Published: February 2025

If a calamity with a retaining wall occurs, the impact on surrounding buildings and infrastructure is at least an order of magnitude more severe than without the calamity. In 2005 and 2006 major leaks in the retaining walls of underground stations in Amsterdam and Rotterdam occurred. After these cases had been thoroughly studied it was concluded that the diaphragm walls had anomalies in the joints between the D-wall panels. These anomalies are hard to locate using regular leakage detection systems and may cause major damage to the surroundings if an erosive leak progresses. Such a risk is hard to handle for a project and may stand in the way of the application of D-walls close to adjacent buildings. Between 2009 and 2014, within the GeoImpuls program, research was done to develop measurements to detect these anomalies. Three techniques have been found to be effective in evaluating the quality of the concrete in the joint area between D-wall panels.
Multi-Objective Optimization and Decision Aid for Spread Footing Design in Uncertain Environment
Authors: Piegay Nicolas  , Breysse Denys
Published: February 2025

This paper aims to present an evaluation, optimization and comparison approach for the design of isolated spread foundations in an uncertain environment. The choice of the optimal solution is made according to the decision-maker's preferences to find the best compromise between various conflicting objectives. Furthermore, this approach takes into account a set of uncertain parameters (soil properties, loading, critical values...) modeled using Monte-Carlo simulations.
Risk Management of Groundwater During The Reconstruction of the Rotterdam Central area
Authors: de Doelder Bert  , Hannink Geerhard
Published: February 2025

The rather complex subsoil and groundwater conditions have played an important role in the design and execution of projects with extensive excavations in the centre of Rotterdam. These projects comprise of the reconstruction of a subway station, two new traffic tunnels, an underground bicycle parking facility and a new railway terminal. The realisation of these projects involve a number of risks. This paper describes the main hydrological risks during the realisation of the different projects around the railway station Rotterdam Centraal. Three risks are presented in more detail, illustrating that knowledge of the local groundwater regime is a precondition for realising projects with controlled risks.
Granular Contact Dynamics for the Probabilistic Stability Analysis of Slopes
Authors: Meng J.  , Huang J.  , Sloan S.W.
Published: February 2025

Slope instability and landslides can be catastrophic events often leading to loss of life and property. To assess the risks of slope failures, it is often desired that the dynamic process of slope failure can be simulated. This paper proposes a Granular Contact Dynamics (GCD) approach based on variational principles and implicit time integration to simulate the failure process of slopes. The method has the ability to simulate fracture initiation and development (i.e., progressive failure process) and allows the consequence of slope failures to be assessed quantitatively. A two dimensional example is given to demonstrate the method.
Reliability Analysis of Heterogeneous Slope Considering Effect of Distribution Types
Authors: Jiang Shuihua  , Li Dianqing  , Wei Bowen
Published: February 2025

The effect of probability distributions on the slope reliability is highlighted in this study since the lognormal distribution is often used to characterize the variability of soil properties to avoid negative values. A multiple response-surface based MCS method for slope reliability analysis in spatially variable soils is proposed. A heterogeneous slope consisting of three soil layers (including a weak layer) is studied to demonstrate the validity of the proposed method and explore the effect of probability distributions for soil shear strength parameters on the reliability of the heterogeneous slope. The results indicate that the proposed method provides a practical tool for evaluating the reliability of heterogeneous slopes in spatially variable soils. The difference in the probabilities of failure of the heterogeneous slope associated with the lognormal, normal, gamma and beta distributions is significant when the spatial variability of multiple soil properties is incorporated. In general, the probability of failure may be underestimated as the lognormal distribution is used for characterization of the random fields of soil properties.
Behaviour of geocell reinforced sub-ballast under cyclic loading
Authors: Biabani M. Mahdi  , Indraratna Buddhima  , Nimbalkar Sanjay
Published: February 2025

With the advent of high speed trains, large cyclic stresses are exerted on ballasted rail tracks which in turn cause excessive settlements and lateral deformations of granular materials leading to frequent maintenance of track. The use of planar reinforcement is well established in rail environment to address such aspects. Recent studies have shown that geocell can provide much better lateral confinement to infill soil compared to planar reinforcement. However, a limited number of researches have been performed to examine the performance of reinforced sub-ballast under cyclic loading in railway environment. In this study, the large-scale prismoidal triaxial apparatus have been employed to investigate the performance of reinforced and unreinforced sub-ballast during cyclic loading. A series of drained tests were carried out to examine the behaviour of unreinforced and geocell reinforced sub-ballast subjected to cyclic loading exerted by train passes. The laboratory experiments were carried out in plane strain condition at very low confining pressure to simulate railway environment. Effects of varying apparent confining pressure (σ′3), frequency (f) and number of load cycles (N) were also studied.
Experimental Study on Deformation of Improved Soil Used as Seismic Strengthening Material of Existing Pile Foundations
Authors: Tomisawa Koichi  , Kimura Makoto
Published: February 2025

Nowadays, based on the experiences in the recent severe earthquakes, it has been recognized that a certain level of seismic performance is required for the foundation design of newly-built bridges. However, a large number of existing pile foundations with serious deteriorations and damageshave to be improved and strengthened for the safety of highway system during earthquake. In this paper, a new technique to improve seismic performance of existing pile foundations constructed in very soft or liquefiable ground by introducing improved soil around the pile heads is proposed.Seismic performance of pile foundation with improved soil subjected to Level 2 Earthquake wave was investigated through dynamic loading tests for model piles using a large-scale shaking table.As a result, the maximum bending strain of pile with improved soil was reduced to half of that without improved soil, and the validity of the proposed seismic strengthening method for existing pile foundations was verified.
Estudio Experimental Sobre Arenas Reforzadas con Geogrillas
Authors: Useche Infante Danny  , Martinez Gonzalo Aiassa  , Arrua Pedro  , Eberhardt Marcelo
Published: February 2025

En la literatura técnica se encuentran diversas investigaciones que evidencian el mejoramiento en el comportamiento de las fundaciones superficiales con la inclusión de geosintéticos. Esto gracias a que la fuerza de tracción del geosintético proporciona una función de refuerzo al suelo y permite una mejor distribución de las presiones en el mismo. En este trabajo se realiza una investigación experimental del comportamiento mecánico del suelo reforzado, por medio de ensayos CBR sobre muestras de arena con inclusión de geogrillas. El ensayo CBR permite medir la deformación vertical ante la aplicación de cargas verticales con lo que es posible caracterizar el comportamiento esfuerzo-deformación del material. Las pruebas son realizadas con arena medio densa usada comúnmente como base para fundaciones y terraplenes en Córdoba, así mismo se emplean geogrillas comercializadas en el medio local para realizar el análisis. Los ensayos se llevan a cabo para suelo reforzado con diferente número de capas de geogrilla y para suelo sin reforzamiento con el fin de determinar el mejoramiento que se alcanza con la inclusión de estos materiales en la masa de suelo.
Evaluation Of Primary And Secondary Deformations and Particle Breakage of Tailings
Authors: Bhanbhro Riaz  , Rodriguez Juan  , Edeskär Tommy  , Knutsson Sven
Published: February 2025

Tailings are the waste product of mining which is left over after extraction of materials of interest. Tailings material may possess different material properties depending upon type of ore and method of concentration. Sometimes the tailings material itself is used in construction of tailings dams and tailings dams are constructed to withstand for long times. A tailing dam can be exposed to settlements due to incremental load as these dams are raised in stages. Increasing load with time may also lead to particle breakage. This article presents the results from oedometer tests conducted on tailings materials. The study includes the stress-deformation behavior and particle breakage of tailings material of different gradations upon application of incremental loads in oedometer tests. The samples were collected from different sections of tailings dam from Sweden. Remolded samples were manufactured in laboratory as four batches of particle sizes i.e. 1-0.5 mm, 0.5-0.25mm, 0.25-0.125mm and 0.125-0.063mm. The results are analyzed from tested samples at different stress levels and compared with different particle sizes. The breakage of particles of each batch is analyzed by sieving the specimens after oedometer tests. The results are evaluated in terms of primary and secondary deformations. The primary and secondary deformations are also compared with different particle sized specimens.
Shear Strength Parameters of a Heap Leach Material
Authors: Oldecop Luciano A.  , Rodari Rubén  , Zabala Francisco  , Mazuelos Oscar
Published: February 2025

Heap leaching involves the stacking of gravel-size materials produced by grinding. Such materials can contain significant amounts of fines arising from the alteration or weathering of the parent rock. To enable transport, placing and pile operation, it is convenient to induce fines agglomeration with the gravel particles by mixing the material with moderate amounts of water. Moreover, the placing procedure in the heap is often conducted by pouring the material over the top of the pile from portable conveyor belts with no additional compaction. The combination of these procedures yields extraordinarily loose states. For instance, in the case studied in this paper, the placing dry unit weight measured in the field was as low as 16 KN/m3, while the laboratory determined minimum and maximum dry densities (ASTM D4254 & D4253) were 19 and 21 KN/m3, respectively. Despite the fact that the leach heaps are designed to operate in unsaturated condition, experience shows that it is not uncommon that some parts of the stack become saturated at some point of their operation or the closure phase. This may arise from just the sprinkling of leaching solution, or in combination with water inflow from rain or snowmelt. Moreover, segregation during placing, transit of equipment, fines migration and clogging may cause local variations of the materials permeability, producing the elevation of the phreatic level or even perched water tables. If such conditions are met in a significant volume within the pile, the undrained behaviour of the material is of paramount importance, considering its expected contractive tendency. Static and earthquake-triggered liquefaction have already been observed in some few cases around the world. In this paper, the undrained shear strength of a heap leach pile material is investigated by means of large-size triaxial tests. A series of consolidated-undrained tests were conducted on remolded specimens prepared at various initial void ratios. Emphasis was placed on careful measurement of initial void ratio and volume changes during the test, in order to obtain the best possible approximation to the critical state line.
Análise Sísmica e hidro-mecânica de uma barragem de terra zonada no Peru
Authors: Esaine Barrantes Perlita  , Romanel Celso
Published: February 2025

O presente estudo trata do comportamento da barragem de Recreta, de terra zonada, situada na província de Huaraz – Peru, durante a sua construção, primeiro enchimento do reservatório e ao longo do período de avanço da frente de saturação, através de uma análise acoplada hidro-mecânica; e quando submetido a exitação sísmica, por estar situada em um área de atividade sísmica. O comportamento estático e dinâmico da barragem foi simulado pelo método dos elementos finitos (programa computacional PLAXIS 2D) utilizando os modelos constitutivos de Mohr-Coulomb e HSsmall (Hard Soil Small Model). Os resultados numéricos são discutidos em termos de deslocamentos e poropressões nas diversas fases de análise, incluindo a estabilidade de taludes. A análise dinâmica envolve uma série de cuidados na modelagem do problema e estabelecer adequados níveis de amortecimento do material.
Design and Performance of a Deep Excavation Sharing a Common Wall with a Metro Station in Service
Authors: Zhou Liang  , Zhang Zhong-jie  , Li Ming-guang  , Wang Jian-hua  , Chen Jin-jian
Published: February 2025

Substructures are always affected by soil unloading in adjacent deep excavation. However, the unloading effect can be reduced with rational design and construction schemes. This paper presents the design and performance of a deep excavation in Shanghai, China. The deep excavation is distinctive because it shares a retaining wall with an operating metro station with a length of 150 m. During construction, potential large heaves of the metro lines are expected due to unloading effect in the excavation. To reduce the unloading effect and protect the metro station in service, a temporary partition wall is constructed paralleling to the metro station with a distance of 18 m away from its external wall. Thus the whole excavation is divided into two independent pits and the dimensions of the small one are 18 m by 150 m. Therefore, the unloading effect on deformation of the metro station can be reduced and the metro station can be protected. To confirm the efficiency of this construction scheme and ensure the safety of the metro station, a comprehensive field monitoring program is conducted throughout the construction period. Deformation behaviors of both the supporting system and the metro lines are presented in this paper. Results show that the deformations of the supporting system are well controlled and the maximum uplift of the metro lines is only 15 mm, which is less than the allowable value, i.e. 20 mm.
Monitoreo de Hincado de Pilotes a través del Equipo PDA – Nuevo Muelle del Puerto de Paita, Perú
Authors: Machado Luís
Published: February 2025

El Aseguramiento de la Calidad del producto acabado y la capacidad de actualización a nuevos conocimientos, metodologías y tecnologías, son parámetros fundamentales de competitividad para una empresa de Construcción Civil. En una era de boom tecnológico, todos los días hay nuevas herramientas que visan contribuir para la ejecución de proyectos más ajustados a las necesidades de las personas y al entorno, permitiendo al mismo tiempo que estos sean más rentables y puedan ser implementados en menor plazo. Cuando hablamos de estructuras geotécnicas, como es el caso de los pilotes, el grado de incertidumbre crece y la utilidad de esas herramientas es todavía mayor. En ese sentido, durante este trabajo, se abordará la monitorización de hincados a través del equipo PDA, demostrándose su utilidad en la definición de las longitudes de los pilotes y en el control de los parámetros de hincado y de la calidad de las estructuras.
Penetration tests in shallow layered unsaturated pyroclastic soil deposits of Southern Italy
Authors: Cuomo Sabatino  , Foresta Vito
Published: February 2025

The paper deals with a recent extensive in-situ and laboratory investigation carried out in a site characterized by thin layered unsaturated air-fall volcanic (pyroclastic) soil deposits, which are very steep and prone to slope failures turning into catastrophic flows (Cervinara, Southern Italy). The field campaign was based on iron-rod drillings, penetration tests and hand-excavated shafts, beside to the collection of undisturbed soil specimens used for laboratory tests. The real sequence of the soil layers was identified in more than two hundreds verticals. In addition, while a series of available literature formulas are detected as unreliable for these soils, the paper propose new reliable empirical correlations between the soil friction angle (of three lithotypes) and both the number of blows of the penetration test and the vertical stress.
Innovative Application of Mechanical ND In-situ Tests for Generating Foundation and Pavement Structural Design Parameters
Authors: Mukabi John
Published: February 2025

This study proposes innovative conceptual models that enable the application of in-situ test data from mechanical tests such as the DCP (Dynamic Cone Penetration) and the SPT (Standard Penetration Test) to directly determine not only the elastic stiffness but also derive physical properties and such other essential parameters as bearing capacity and shear strength from the same. Case examples of their successful application for the design of foundations and pavement structures in the East and Central African Region and further models correlating in-situ mechanical to geophysical as well as in-situ to popular laboratory tests are also provided.
Leakage analysis through composite liners in landfills
Authors: Montoro Marcos A.  , Francisca Franco M.  , Juarez Manuel A.
Published: February 2025

Liner system reliability is of key importance for landfill risk mitigation. There are many design recommendations and standards from several environmental agencies around the world. Among them, single liners and composite liners designs are frequently used. In this article, leakage through single and composite liners was determined in order to evaluate environmental risk. A sensitivity analysis of the governing equation for flow through geomembrane holes was performed and a Monte Carlo simulation for single and composite liner leak was performed. Obtained results allowed confirming that quality control during construction and operation is of key importance for liners performance. Also these findings helped to statistically determinate the equivalency between different alternative liners for the containment of landfill leachate.
Theoretical and Experimental Correlation between Thermal Conductivity and Dielectric Permittivity of Soils
Authors: Hailemariam Henok  , Shrestha Dinesh  , Wuttke Frank  , Wagner Norman
Published: February 2025

Accurate determination of thermal conductivity can be achieved through measurements of soil parameters which are strongly coupled to thermal conductivity. One such parameter is soil dielectric permittivity or conductivity. Several researchers, De Vries 1963 [1], Tarnawski 2000 [2] and Archie 1942 [3], have shown that both the thermal conductivity and dielectric permittivity or conductivity of soil depend on same parameters such as chemical composition, soil structure, and hydro-mechanical properties. In this research, the relationship between thermal conductivity and dielectric permittivity of soils was theoretically and experimentally studied. For this purpose, the thermal conductivity and dielectric permittivity of three silty clay soils, with known chemical and hydro-mechanical properties, were studied simultaneously under varying conditions of soil moisture. As expected, strong correlations between thermal conductivity and dielectric permittivity were obtained.
Geotechnical and chemical characterization of recycled construction and demolition waste (RCDW) for pavements
Authors: Lukiantchuki Juliana Azoia  , Moreira da Silva de Oliveira José Renato  , dos Reis Jeselay Hemetério Cordeiro
Published: February 2025

This paper presents the geotechnical and chemical characterization of recycled construction and demolition waste (RCDW) for pavement purposes. Geotechnical tests show that the material is predominantly composed of sand, which can be characterized as a poorly graded non-uniform soil. The uniformity coefficient (Cu) and the curvature coefficient (Cc) are equal to 62 and 8.5, respectively. The percent passing through a 42 mm sieve is 38%, which is in accordance with the Brazilian Association of Technical Norms. Additionally, grain size distribution shows that the RCDW is recommended for N < 5×106(traffic characteristics). The unconfined compressive strength of RCDW is about 80 kPa, which is significantly lower than the minimum required value. The addition of 2.5% of cement was not sufficient to reach this value, although additional tests are recommended to define the optimum amount of cement or other material.
Biorremediação In Situ de Biodiesel Através da Atenuação Natural, Bioestimulação e Bioventilação
Authors: Cecchin Iziquiel  , Reginatto Cleomar  , Thomé Antonio  , Colla Luciane  , Schnaid Fernando
Published: February 2025

Although less harmful to the environment, biodiesel is not always handled and stored properly, causing environmental contamination by leaks. Among the existing techniques, natural attenuation stands out by being an inexpensive and efficient technique that utilizes autochthonous soil microorganisms to biodegrade the contaminant or reduce the toxicity. Most of the work involving bioremediation techniques is performed in the laboratory with controlled conditions. This paper aims to evaluate three different techniques in situ bioremediation of a simulated contamination of biodiesel in a clay soil. The soil was collected at 2 meters deep and contaminated with 4% of biodiesel in the dry mass of soil, maintaining the natural moisture and density in the similar field. For assembling the bioremediation reactors, we used two polyethylene boxes with capacity of 2 m3(1m Øand height of 1.72 m). To simulate the contamination of the underground, the reactors were installed to 2 meters deep. It was adopted three treatments: natural attenuation, biostimulation with bioventing and biostimulation with bioventing and nutrients. The analyzes were performed at three depths – 1.3; 1.6 and 1.9 meters. The analysis evaluated the residual contaminant content in three experiments from the ultrasound method, in the times: 15, 30, 45, 60, 90 and 120 days. Among the bioestimulation treatments, the experiment with bioventing obtained a contaminant reduction of 48.97%, while the results of the experimental unit whit addition of nutrients + bioventing reaches to a reduction of 56.47 %. The results obtained in situ have confirmed a more effective interaction between bioventing and biostimulation with nutrients. However, the results obtained in situ confront the results presented in the literature, where the contamination reduction is lower than those obtained in laboratory tests, demonstrating the great influence of abiotic factors on the effectiveness of bioremediation techniques.
Reinforced Hollow Cylinders and Boreholes
Authors: Papamichos Euripides
Published: February 2025

Rock nailing of boreholes is considered a means to reinforce the rock and increase its borehole failure strength. Nail reinforcement improves stability by increasing the normal force and hence the rock shear resistance along potential slip surfaces and localization zones. In a continuum sense, nail reinforcement is modeled as a body force. A numerical finite element formulation is developed that couples the rock and the nail behavior and solves the equations simultaneously. The numerical results are verified against analytical solutions for reinforced elastic boreholes and hollow cylinder geometries. Comparison of the reinforcement effect in boreholes and hollow cylinders shows that the hollow cylinder test has to be specially designed to model realistically the field conditions.
Blind image forgeries detection using detail components from the wavelet transform
Authors: Le-Tien Thuong  , Huynh-Kha Tu  , Bui-Duc Sinh
Published: February 2025

In this study, the wavelet transform based method is proposed to detect image forgeries. Based on the wavelet transform properties, the suspected regions of digital images are detected. It can be known, the wavelet transform gives a variety of output components, including the Approximation, Horizontal Detail, Vertical Detail and Diagonal Detail. The detail components provide the information of edges, if a region is copy-moved or spliced, the edges of this region will be not naturally, thus they can be detected by analyzing the detail components. Due to this characteristic, an efficient approach in digital image is developed for using the detail components of wavelet transformed images. To increasing the accuracy of the approach, a preprocessing step and the morphological processing are applied in the method. The simulating results prove the robust and efficiency of this approach with low computational time and proper accuracy.
COAR Case Study Controlled Vocabularies and PHAIDRA International
Authors: Subirat Imma  , Solodovnik Iryna  , Budroni Paolo  , Ganguly Raman  , Hudak Rastislav
Published: February 2025

Following the COAR-SPARC conference in Porto, the COAR Controlled Vocabularies Interest Group met on the 16thof April 2015 and had a detailed discussion about the new set of COAR controlled vocabularies, while proposing detailed actions to solve the remaining issues (mainly in the Resource Type vocabulary). Echoing aspects discussed about sustainability and organization (long-term technical support), as well as dissemination and implementation of COAR controlled vocabularies, the immediate projection of these issues has seemed to be quite feasible on PHAIDRA International long-term ecosystem. Nowadays this OAI-PMH environment consists of fourteen Open Access repositories disseminating their contents to EUROPEANA, OpenAIRE, OAPENLibrary, e-infrastructures Austria, and national CRIS etc. PHAIDRA International is taking all necessary steps to be constantly aligned with Trusted Digital Repositories criteria and harmonized (technically and semantically) in line with COAR Roadmap: Future Directions for Repository Interoperability. The COAR Roadmap stresses that still many challenges remain with improving interoperability. These involve standardization of controlled vocabularies in use, as well as metadata and indicators, in connection with state-of-the-art interoperability approaches supporting Linked Open Data. There is an urgent need for PHAIDRA International to harmonize the encoding description (metadata properties) according to LOD-enabling strategies, and to adhere to multilingual COAR controlled vocabularies" shared registry (Knowledge Base) services. COAR Controlled Vocabularies can be easily implemented in PHAIDRA in fixed formats and mapped to related persistent RDF/SKOS versions.
Renegotiating Open-Access-Licences for Scientific Films
Authors: Brehm Elke
Published: February 2025

Scientific publishing is not limited to text any more, but more and more extends also to digital audio-visual media. Thus services for publishing these media in portals designed for scientific content, oriented towards the demands of scientists and which comply with the requirements of Open Access Licenses must be provided. Among others, it is the goal of the Competence Centre for Non-textual-materials of TIB to collect, archive and provide access to scientific audio-visual media in the TIB AV-Portal under the best possible (open) conditions. This applies to older films, as for example the film collection of the former IWF Knowledge and Media gGmbH i. L. (IWF) and to new films. However, even if the acquisition of the necessary rights for audio-visual media is complex, the renegotiation of Open-Access-Licenses for older films is very successful. This paper focuses on the role of Open Access in the licensing strategy of TIB regarding scientific films, the respective experience of TIB and the presentation in the AV-Portal, but also touches upon prerequisites and procedures for the use of Orphan Works.