bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultrasonic pulse velocity used to predict the compressive strength of structural sand lightweight concrete
Authors: Bogas J. Alexandre  , Gomes M. Glória  , Real Sofia  , Pontes Jorge
Published: February 2025

This paper aims at evaluating the compressive strength of structural sand lightweight aggregate concrete (LWC) by the non-destructive ultrasonic pulse velocity method. To this end, a comprehensive experimental study was carried out involving more than 70 different compositions tested between 3 and 180 days with mean compressive strengths ranging from about 30 to 80 MPa and density classes from D1.6 to D2.0. The influence of several factors on the relation between the ultrasonic pulse velocity (UPV) and compressive strength was examined, including the type and binder content, type and volume of aggregates. It is found that lightweight and normal weight concretes (NWC) are affected differently by mix design parameters. NWC is more affected by the volume of aggregate and the dispersion effect caused by concrete heterogeneity tends to be lower in LWC. The prediction of the concrete's compressive strength by means of the non-destructive UPV test is analysed. Based on the dependence of the UPV on the density and elasticity of concrete, a simplified expression is proposed to estimate the compressive strength, regardless of the type of concrete and its composition. High correlation coefficients were obtained taking into account several results for different types of aggregates and concrete compositions.
Achieving concrete durability for specified service-life in chloride exposures
Authors: Hooton R.Doug
Published: February 2025

Obtaining durability for a known service life in chloride exposures requires knowledge of the concrete properties, relevant transport processes, depth of cover as well as minimization of cracking and construction defects. For example, imperfect curing can result in depth-dependent effects on resistance to chloride ingress. Several service life models with various levels of sophistication exist for prediction of time-to-corrosion of concrete structures exposed to chlorides. The model inputs have uncertainty associated with them such as boundary conditions (level of saturation and temperature), cover depths, diffusion coefficients, time-dependent changes, and rates of buildup of chlorides at the surface. The performance test methods used to obtain predictive model inputs as well as how models handle these properties have a dramatic impact on predicted service lives. Very few models deal with the influence of cracks or the fact that concrete in the cover zone will almost certainly have a higher diffusion coefficient than the bulk concrete as the result of imperfect curing or compaction. While many models account for variability in input properties, they will never be able to account for extremes in construction defects. Therefore, to ensure the reliability of service life predictions and to attain a concrete structure that achieves its predicted potential, designers, contractors and suppliers need to work together to ensure proper detailing, minimize defects, and adopt adequate, yet achievable, curing procedures. As well, concrete structures are often exposed to other destructive elements in addition to chlorides (eg frost, ASR) and this adds another level of complexity since regardless of cause, cracks will accelerate the ingress of chlorides. These issues are discussed along with the need to use performance-based specifications together with predictive models.
Research on a novel technology of FRP bonded to concrete substrate without adhesive
Authors: Li Ming  , Liu Yunpeng  , Liu Muyu  , Wang Fazhou
Published: February 2025

Without any treatment for concrete surface, a novel technology of FRP bonded to concrete substrate without adhesive was developed, in which the porous lightweight aggregate was used as bridge material between FRP sheet and concrete. Base on that technology, a prefabricated rough FRP sheet which can be used accompanying with concrete pouring was presented with the aim to improve the durability of concrete, which has a great potential to be widely used in the area of reinforcement, surface decoration and protection for concrete construction. The durability of rough FRP sheet was preliminarily evaluated by pull-off test and chloride ion penetration test. Results indicated that bond strength between rough FRP sheet and concrete substrate was 2.17MPa, chloride ion permeability coefficient at 30 days was 8.41×10−4mg/d·cm2. Microstructure analysis showed that the bond strength was mainly determined by mechanical interlocking and interfacial structure between lightweight aggregate and cement paste, an equation based on the bond model was put forward to optimize the design of rough FRP sheet.
Sulphate corrosion behaviour of high volume slag concrete
Authors: Ekolu Stephen O.  , Ngwenya Adam
Published: February 2025

Concrete mixes of water-cementitious ratio (w/c's) = 0.45, 0.5, 0.65 were used to prepare 100 mm cubes and 75 x 75 x 285 mm prisms. Moderately high alumina slag was incorporated in proportions of 50 or 70% and the specimens immersed in sodium sulphate or magnesium sulphate solutions of 50 g/L as SO4. Emphasis in the study was to assess sulphate resistance using concrete samples and other non-conventional methods. Expansion measurements, mass loss and corrosion attack or physical deterioration of concrete were monitored for 69 weeks. It was found that the results of expansion, mass gain and corrosion were consistent for Na2SO4solution, showing improved sulphate resistance with increase in ground granulated blast-furnace slag (GGBS) incorporation. The expansion observations under MgSO4, while showing increased resistance with use of GGBS, gave conflicting results between expansion on one hand and, mass gain and corrosion on the other with the most severe corrosion occurring in concrete containing the high 70% GGBS. The corrosion test method appears to give a more realistic indicator of physical damage under MgSO4attack compared to expansion measurement.
Indicative tests on the effect of fly ash-β cyclodextrin composite on mortar and concrete permeability, sorptivity and porosity
Authors: Ikotun B.D.  , Fanourakis G.C.  , Mishra S.
Published: February 2025

The focus of this research is to modify fly ash (FA) structure using β-cyclodextrin (β-CD) to increase its pozzolanic function in concrete. A previous study by the authors has shown that a composite is formed due to structural changes of fly ash by its interaction with cyclodextrin [1]. The objective of this paper was to assess the effect of fly ash-βcyclodextrin composite (FA-β-CD) on the transport properties (durability performance) of mortar and concrete, with a view to optimise its incorporation in concrete. The durability performance of mortar and concrete were assessed from the measurement of oxygen gas permeability, sorptivity and porosity using the South Africa durability index approach. Six mixtures were tested, comprising a control mixture (100% Portland Cement, PC), and five mixes containing the FA-β CD composite. All the composite mixes included 30 % FA by mass. The β-CD was mixed with the FA, in separate mixtures, in proportions of 0.1 %, 0.2 % and 0.5 %. Two sample preparation procedures were followed for FA-β-CD composites mixtures; firstly, physical mixtures of a pre-weighed amount of β-CD and FA were adopted for the dry mixtures and secondly, 0.0103M, 0.0206M and 0.0516Mβ-CD solutions were added to the concrete at the mixing stage for solution mixtures. The results indicated that FA-β-CD composite improved the flowability and durability performances when β-cyclodextrin (β-CD) was used at a lower percentage (0.1% and 0.2%).
Effects of pit-sand on shear capacity of reinforced concrete space framed structures: Case study of a building at Oba – Ile Akure
Authors: Olanitori Lekan Makanju  , Afolayan Joseph Olaseinde
Published: February 2025

In the Nigerian construction industry today, there were instances when the prescribed concrete strength by the consultant structural engineer is not achieved during construction, due to the poor quality of available sand. This paper evaluates the existing formulae used in estimating the shear capacity of reinforced concrete structures and assesses the effect of concrete produced from pit-sand in Akure metropolis, on the shear capacity of a collapsed building in Oba-Ile, Akure. Site inspections were carried out on the collapsed building, and concrete samples were taken. Both destructive and non-destructive methods were used to determine the structure's concrete strength. Many of the structural members were exposed, so as to determine the number of reinforcements in each structural element. The shear capacity of the structure was estimated using existing formulae and, compared it with the structure's actual shear capacity. The average concrete strength was 8.5 N/mm2which is less than 20 N/mm2, the prescribed concrete strength for construction of the building. The estimated shear capacity based on 8.5 N/mm2and 20 N/mm2concrete strengths were 93.9 kN and 118 kN respectively, while the actual shear capacity at collapse was 18.88 kN. The actual shear capacity is less than the estimated shear capacity of the collapsed building, because of the reduced concrete strength due to the poor quality of pit-sand used for the concrete work; hence the collapse of the building was by shear failure induced by the reduction in concrete strength.
Study on the mechanical property recovery of concrete subjected to elevated temperatures
Authors: Li Qingtao  , Yuan Guanglin  , Shu Qianjin
Published: February 2025

This investigation was aimed at improving the recovery of the compressive strength, the splitting tensile strength and the static modulus of elasticity of concrete subjected to elevated temperature. Normal-strength concrete with water-cement ratio of 0.50 was prepared and exposed to 200 °C and 600 °C. Two cooling regimens were used including natural cooling and spraying water for 30 min. After cooling, the specimens were subjected to two post-fire-curing methods with and without performance-modifying agent (PMA) for a total duration of 180 days. The compressive strength, the splitting tensile strength and the static modulus of elasticity of concrete were measured to examine the changes in the mechanical properties of concrete. The test results indicated that the PMA could improve the recovery of the compressive strength, the splitting tensile strength and the static modulus of elasticity of concrete subjected to 200 °C and 600 °C.
Reducing Nosocomial Infections: A User-centered Approach to Developing an eHealth system for Sri Lankan ICUs
Authors: Kariyawasam Nadish  , Wong Ming Chao  , Mahipala Palitha  , Turner Paul
Published: February 2025

Nosocomial infections are a health concern in hospitals both in developed and developing countries. Immuno-compromised patients in intensive care units (ICU) have been identified as being particularly vulnerable. However, despite numerous interventions, infection rates remain high and antibiotic resistance is now of global concern. In Sri Lanka, higher than anticipated infection rates appear linked to a range of factors including hierarchical work flow, poor surveillance feedback and health staff attitudes and awareness. By deploying a user-centered approach to understanding these factors this research-in-progress will develop and evaluate the capacity of an eHealth system to contribute to reduction of nosocomial infections in Sri Lankan ICUs.
eHealth for Remote Regions: Findings from Central Asia Health Systems Strengthening Project
Authors: Sajwani Afroz  , Qureshi Kiran  , Shaikh Tehniat  , Sayani Saleem
Published: February 2025

Isolated communities in remote regions of Afghanistan, Kyrgyz Republic, Pakistan and Tajikistan lack access to high-quality, low-cost health care services, forcing them to travel to distant parts of the country, bearing an unnecessary financial burden. The eHealth Programme under Central Asia Health Systems Strengthening (CAHSS) Project, a joint initiative between the Aga Khan Foundation, Canada and the Government of Canada, was initiated in 2013 with the aim to utilize Information and Communication Technologies to link health care institutions and providers with rural communities to provide comprehensive and coordinated care, helping minimize the barriers of distance and time. Under the CAHSS Project, access to low-cost, quality health care is provided through a regional hub and spoke teleconsultation network of government and non-government health facilities. In addition, capacity building initiatives are offered to health professionals. By 2017, the network is expected to connect seven Tier 1 tertiary care facilities with 14 Tier 2 secondary care facilities for teleconsultation and eLearning. From April 2013 to September 2014, 6140 teleconsultations have been provided across the project sites. Additionally, 52 new eLearning sessions have been developed and 2020 staff members have benefitted from eLearning sessions. Ethics and patient rights are respected during project implementation.
Self healing materials for bone regeneration
Authors: Douglas Timothy E.L.  , Leeuwenburgh Sander
Published: February 2025

Bone is a well known natural self-healing composite material, which consists of an organic component in the form of a collagen fibril-based hydrogel and an inorganic component in the form of calcium phosphate (CaP) crystals which reinforce the hydrogel.
The Importance of Architectures for Interoperability
Authors: Blobel Bernd  , Oemig Frank
Published: February 2025

The paradigm changes health systems are faced with result in highly complex and distributed systems requiring flexibility, autonomy, but first of all advanced interoperability. In that context, understanding the architecture of the system to be supported as well as the process to meet the intended business objectives is crucial. Unfortunately, there is a lot of confusion around the term architecture, which doesn't facilitate the integration of systems. Using a reference architecture model and framework, relevant existing architectural approaches are analyzed, compared and critically discussed, but also harmonized using a reference architectural model and framework.
A Study of Different Fabrics to Increase Radar Cross Section of Humans
Authors: Ödman Torbjörn  , Welinder Jan  , Andersson Nils  , Otterskog Magnus  , Lindén Maria  , Ödman Natalia  , Larsson Christer
Published: February 2025

This purpose of the study was to increase the visibility on radar for unprotected pedestrians with the aid of conducting fabric. The experiment comprised measurements of four types of fabric to determine the radio frequency properties, such as radar cross section (RCS) for the vehicle radar frequency 77 GHz and transmission (shielding) in the frequency range 3-18 GHz. Two different thicknesses of polypyrrole (PPy) nonvowen fabric were tested and one thickness for 30 % and 40 % stainless steel fabrics respectively. A jacket with the thinner nonvowen material and one with 40 % steel were tested and compared to an unmodified jacket in the RCS measurement. The measurement showed an increase in RCS of 4 dB for the jacket with the 40 % steel lining compared to the unmodified jacket. The transmission measurement was aimed at determining the fabric with the highest transmission of an incoming radio wave. The 30 % steel fabric and the two thicknesses of the nonvowen fabrics were tested. One practical application is for example the use of radar reflective material in search and rescue (SAR) clothes. The study showed that the 30 % steel fabric was the best candidate for further RCS measurements.
Groundwater of the Municipalities of Southwestern Coastal Bangladesh
Authors: Kumar Datta Dilip  , Kumar Ghosh Prosun
Published: February 2025

Aquifers of the urban conglomerates in the southwestern coastal Bangladesh—situated at the heart of the Ganges delta—are susceptible to contamination and induced saltwater intrusion because of population pressure demanding for freshwater and other anthropogenic interventions and thus are vulnerable in terms of quality and quantity. This comprehensive review endeavours to elucidate the geochemistry of solute load of such aquifers for its monitoring, management and conservation. One hundred and seventy numbers of groundwater samples from the production tube wells, penetrating mostly the shallow coastal alluvial aquifers, collected in different periods from Bagerhat, Faridpur, Jhenaidah, Paikgacha and Satkhira municipalities and Khulna City Corporation (KCC) are analyzed for major cations and anions following standard methods. The results show that the abundance of cations follow the general trend Na>Ca>Mg>K for Bagerhat, Paikgacha and KCC and Ca>Mg>Na>K for Satkhira, Jhanaidah and Faridpur municipalities. The anions on the other hand follows the general trend of HCO3>Cl>SO4>PO4for Satkhira, Jhenaidah, Faridpur and KCC and Q>HCO3>SO4>PO4for Bagerhat and Paikgacha. The spatial variation of soute load to the aquifers is statistically quite significant. Molar ionic ratio of chemical parameters suggests both carbonates and plagioclase silicates as their source rock. However seawater intrusion to the aquifers is quite revealing, may be due to localized upwelling of saline waters. Most of the groundwater is supersaturated with respect to both calcite and dolomite suggesting absence of nucleation for calcite precipitation.
Applications of GIS and Remote Sensing for Sustainable Use and Management of Groundwater: A Case Study from the Northwestern Coastal Area of Sri Lanka
Authors: Jayasingha Pathmakumara  , Pitawala A.  , Dharamagunawardhane H.A.  , Welagedara A.S.  , Jayathilaka Kanchana
Published: February 2025

Presently, Sri Lankan coastal groundwater resources is threatened due to various anthropogenic activities and becoming a vulnerable source of water in the country. Northwestern coastal area of the country is characterized by unconfined sandy aquifers such as Kalpitiya Peninsula and Mannar Island. This study focuses on application of GIS and remote sensing techniques in assessing the present situation of coastal groundwater with reference to Kalpitiya Peninsula and Mannar Island in view of introducing a suitable monitoring and management plan for conservation of coastal groundwater. Thirteen hydrogeochemical parameters of 150 locations in both Kalpitiya and Mannar areas were analyzed for the samples both collected from dug wells and shallow tube wells in September, 2013. Groundwater Quality Index, Sodium Absorption Ratio, Soluble Sodium Percentage and DRASTIC methods were used to infer the groundwater vulnerability and resistivity imaging technique were also applied to access the groundwater contamination due to seawater intrusion. GIS was applied to integrate and analyze the spatial data obtained from the above techniques. This unconfined coastal sandy aquifer system which is highly specific and productive is a very good freshwater storage and can be considered as a national heritage of the country. Its inherent characters quite dissimilar to the other coastal aquifers can help us infer the potential of easy contamination and vulnerability. Since the Kalpitiya Peninsula (and Mannar Island in future) is subjected to intense vegetable cultivations, groundwater based irrigation and fertilizer applications, groundwater is at risk and already contaminated with regard to few chemical parameters. Thus, an immediate attention is needed for the future sake of existence of those fresh groundwater storages. Remediation measures for Kalpitiya and sound planning for Mannar Island is a must. Understanding the present situation with the application of GIS and remote sensing techniques favours effective data handling and utilization.
Integration of Disease Specific Clinical and Genomics Datasets using I2B2 Framework
Authors: Mohyuddin
Published: February 2025

The availability of a patient's genomic profile along with the clinical profile for providing individualized care and treatment is paving the road for a new era of personalized medicine, and is an important area of focus in current biomedical research. One of the prominent and globally implemented solutions for clinical and genomics data integration in biomedical research is an NIH funded NCBC initiative – Informatics for Integrating Biology and the Beside (I2B2). This paper presents the development of a pilot prototype for integrating patient's clinical and genomics datasets using open source and scalable I2B2 Framework. It focuses on disease specific clinical data and genomic variants, when combined together can be used for informed decision making in clinical practices by healthcare professionals and for further investigations by biomedical researchers. The research was carried out using a case study of King Abdullah International Medical Research Center (KAIMRC) in collaboration with King Fahad National Guard Hospital (KFNGH).
National governance of archetypes in Norway
Authors: Ljosland Bakke Silje
Published: February 2025

Norwegian National ICT has implemented a national governance scheme for archetypes. The scheme uses openEHR, and is possibly the first of its kind worldwide. It introduces several new processes and methods for crowd sourcing clinician input. It has spent much of its first year establishing practical processes and recruiting clinicians, and only a few archetypes has been reviewed and approved. Some non-reusable archetypes have emerged while the governance scheme has established itself, which demonstrates the need for a centralised governance. As the mass of clinician involvement reached a critical point at the end of 2014, the rate of archetype review and approval increased.
Identifying Patients with Depression Using Free-text Clinical Documents
Authors: Zhou Li  , Baughman Amy W.  , Lei Victor J.  , Lai Kenneth H.  , Navathe Amol S.  , Chang Frank  , Sordo Margarita  , Topaz Maxim  , Zhong Feiran  , Murrali Madhavan  , Navathe Shamkant  , Rocha Roberto A.
Published: February 2025

About 1 in 10 adults are reported to exhibit clinical depression and the associated personal, societal, and economic costs are significant. In this study, we applied the MTERMS NLP system and machine learning classification algorithms to identify patients with depression using discharge summaries. Domain experts reviewed both the training and test cases, and classified these cases as depression with a high, intermediate, and low confidence. For depression cases with high confidence, all of the algorithms we tested performed similarly, with MTERMS' knowledge-based decision tree slightly better than the machine learning classifiers, achieving an F-measure of 89.6%. MTERMS also achieved the highest F-measure (70.6%) on intermediate confidence cases. The RIPPER rule learner was the best performing machine learning method, with an F-measure of 70.0%, and a higher precision but lower recall than MTERMS. The proposed NLP-based approach was able to identify a significant portion of the depression cases (about 20%) that were not on the coded diagnosis list.
Using social connection information to improve opinion mining: Identifying negative sentiment about HPV vaccines on Twitter
Authors: Zhou Xujuan  , Coiera Enrico  , Tsafnat Guy  , Arachi Diana  , Ong Mei-Sing  , Dunn Adam G.
Published: February 2025

The manner in which people preferentially interact with others like themselves suggests that information about social connections may be useful in the surveillance of opinions for public health purposes. We examined if social connection information from tweets about human papillomavirus (HPV) vaccines could be used to train classifiers that identify anti-vaccine opinions. From 42,533 tweets posted between October 2013 and March 2014, 2,098 were sampled at random and two investigators independently identified anti-vaccine opinions. Machine learning methods were used to train classifiers using the first three months of data, including content (8,261 text fragments) and social connections (10,758 relationships). Connection-based classifiers performed similarly to content-based classifiers on the first three months of training data, and performed more consistently than content-based classifiers on test data from the subsequent three months. The most accurate classifier achieved an accuracy of 88.6% on the test data set, and used only social connection features. Information about how people are connected, rather than what they write, may be useful for improving public health surveillance methods on Twitter.
Standardized Cardiovascular Quality Assurance Forms with Multilingual Support, UMLS Coding and Medical Concept Analyses
Authors: Varghese Julian  , Schulze Sünninghausen Sarah  , Dugas Martin
Published: February 2025

Standardized quality assurance (QA) plays an import role to maintain and develop success of cardiovascular procedures (CP). Well-established QA models from Germany could be shared in a form repository for world-wide reuse and exchange.
Detecting, Monitoring, and Reporting Possible Adverse Drug Events Using an Arden-Syntax-based Rule Engine
Authors: Fehre Karsten  , Plössnig Manuela  , Schuler Jochen  , Hofer-Dückelmann Christina  , Rappelsberger Andrea  , Adlassnig Klaus-Peter
Published: February 2025

The detection of adverse drug events (ADEs) is an important aspect of improving patient safety. The iMedication system employs predefined triggers associated with significant events in a patient's clinical data to automatically detect possible ADEs. We defined four clinically relevant conditions: hyperkalemia, hyponatremia, renal failure, and over-anticoagulation. These are some of the most relevant ADEs in internal medical and geriatric wards. For each patient, ADE risk scores for all four situations are calculated, compared against a threshold, and judged to be monitored, or reported. A ward-based cockpit view summarizes the results.
Accessible Web Design – The Power of the Personal Message
Authors: Whitney Gill
Published: February 2025

The aim of this paper is to describe ongoing research being carried out to enable people with visual impairments to communicate directly with designers and specifiers of hobby and community web sites to maximise the accessibility of their sites. The research started with an investigation of the accessibility of community and hobby web sites as perceived by a group of visually impaired end users. It is continuing with an investigation into how to best to communicate with web designers who are not experts in web accessibility. The research is making use of communication theory to investigate how terminology describing personal experience can be used in the most effective and powerful way. By working with the users using a Delphi study the research has ensured that the views of the visually impaired end users is successfully transmitted.
Developing Deep Water Excercise Equipment for Low Back Pain (LBP) Patients: medical validation experiences
Authors: Jókai Erika  , Hárságyi Ágnes
Published: February 2025

Authors describe a joint work of practicing physicians and rehabilitation specialist engineers. In our work we wanted to prove the efficacy of deep-water physiotherapy among the hydrotherapy treatments in patients with degenerative chronic low back pain, by monitoring both objective and subjective parameters. On the other hand, we are also seeking the possibilities of developing a water exercise tool which can spare the shoulders, can be used in deep water and is suitable for helping the three-dimensional movements of the spine without burdening the upper limbs and shoulders.
Risk Management based Ground deformation monitoring during Queens Bored Tunnels project
Authors: Mooney Michael  , Grasmick Jacob  , Prantil Eric  , Thompson Andrew
Published: February 2025

Ground, building and utility deformation monitoring is a well-accepted and required practice for underground construction works in urban environments. The availability of real-time monitoring data during construction allows stakeholders to stay ahead of potential problems, to make decisions prior to damage occurrence, and ultimately to reduce damage and cost risk. This paper presents the analysis of a comprehensive monitoring program carried out during the East Side Access Queens bored tunnels project in New York City. The project involved the construction of four near surface, closely spaced metro transit tunnels beneath the rail yards and mainline railroad tracks. The close proximity of the tunnels provides a unique opportunity to examine the influence of multiple closely spaced tunnel openings on ground deformation, particularly the accumulation of vertical surface deflection due to consecutive tunnels. The project also allows for a direct comparison between deformation monitoring techniques as both manual survey based monitoring and automated total station monitoring were used on the project. This paper will provide an overview of the monitoring program as a component of the risk management process on the project. The monitoring program will be described in detail and results will be presented. The paper also addresses potential improvements to risk-reduction through monitoring.
Geotechnical Risks in a Deep Building Pit in The Hague's Old City Centre – Project Veenkade Case Study of the Restoration of an Old Canal and a New Underground Parking Garage
Authors: van Seters Adriaan J.  , Spendel Kees J.
Published: February 2025

In The Hague, a 2 storey parking garage was built beneath a reinstated canal at the Veenkade with 160 parking places. The canal and the parking garage were installed at minimum 3 – 6 m distance from old houses with a shallow foundation by means of a 10 m deep building pit. A risk analysis was undertaken and major risks were identified, resulting in mitigating measures, e.g. compensation grouting in combination with very accurate monitoring. The structure was completed in 2014.
Risk Evolution during the Design of the Adaptation of a Railway Bridge Foundation
Authors: Spruit Rodriaan  , Hannink Geerhard  , Mastbroek Hans  , van Hengstum Luuk
Published: February 2025

During a design process the risk profile of a project continuously evolves. Often a project progresses through a diamond shaped risk envelope. The initial concept is simple, but during the engineering process several risks are defined and mitigated, making the design increasingly complex. With additional investigations and calculations, some of the identified risks can be better defined. As a result, the design should evolve into a matured design in which only a few risks remain. These risks should be manageable. If uncontrollable risks remain, even though the chance of occurrence may be small, this could render the project unfeasible. This paper will show how the risk profile of a bridge foundation adaptation has evolved.
Uplift Risk Maps for Sewerage Renewal Planning in Deltaic Cities
Authors: Borst Mattijs  , van der Hout Ella
Published: February 2025

A method was developed to identify areas where uplift is likely to occur during sewerage renewal. The results were presented as a map that can be used by generalist civil engineers in the early stage of the sewerage renewal planning process.
Influence of Model Accuracy on Load and Resistance Factor Calibration of Steel Strip Walls
Authors: Miyata Yoshihisa  , Bathurst Richard J.  , Otani Yoshinori
Published: February 2025

This study examines the load and resistance factor design calibration for the ultimate pullout limit state for steel strip reinforced soil walls (SSWs). The tensile loads and pullout capacities of reinforcement strips that were measured during full-scale tests are compared with predicted (nominal) values using analytical models recommended by the Public Works Research Center (PWRC) in Japan. Modified load and resistance models are also proposed in this study. The new load model preserves the general form of the current PWRC load equation. A new pullout capacity model is proposed that has the same number of coefficient terms as the current PWRC equation. The coefficients in both new equations are empirical and are selected by back-fitting to measured load and pullout capacity values to achieve a bias mean equal to one and a low coefficient of variation of bias values. Here, bias is the ratio of measured to predicted value. This study demonstrates the influence of model accuracy on the computed resistance factor in LRFD calibration of SSWs for the pullout limit state.
Probabilistic VHM Failure Envelopes for Skirted Foundations in Spatially Variable, Normally Consolidated Clay
Authors: Charlton T.S.  , Rouainia M.
Published: February 2025

Skirted foundations are used in offshore applications to resist the large horizontal and moment loads that are characteristic of the ocean environment. The ultimate capacity of a skirted foundation subjected to vertical-horizontal-moment (VHM) loading combinations can be described using failure envelopes in VHM load space. This represents a far more versatile design approach than classical bearing capacity solutions and is able to accommodate complex loading scenarios and similarly complex stress conditions in the soil. Typically, VHM envelopes are constructed using deterministic plastic limit analyses or numerical methods. However, soil is a natural material and as such is inherently variable. The value of soil parameters fluctuates through the ground, as evident in field or laboratory test results. In this study, the ultimate capacity of a skirted foundation in spatially variable undrained clay under VHM loading is investigated. Spatial variation is taken into account using a random field representation of undrained shear strength and the increase of strength with depth typical of a normally consolidated marine clay is considered. The random field is coupled with a finite element method to assess the ultimate limit state. The failure mechanism and ultimate capacity are consequently direct results of the spatial variation of undrained shear strength. Monte Carlo simulation is used to produce probabilistic failure envelopes, based on the probability that the true combination of VHM loads causing failure will fall inside on or inside that envelope. Hence, this method allows designers to select a failure envelope that is associated with an acceptable level of risk.
Effects of Soil Spatial Variability on Bearing Capacity of Shallow Foundations
Authors: Daryani K.E.  , Mohamad H.
Published: February 2025

This paper studies the effect of soil spatial variability on bearing capacity of shallow foundations. The stochastic soil property is the undrained shear strength considered as a non-Gaussian random variable. The random variable is simulated using Local Average Subdivision Method. A Monte Carlo simulation approach is followed in combination with non-linear finite difference analysis to study the realistic behaviour of the foundations. It is demonstrated that the inherent spatial variability of soil shear strength can drastically modify the basic form of the failure mechanism in this bearing capacity problem. This behavior of the failure mechanism translates into a substantial reduction in the ultimate bearing capacity (in an average sense), compared to the corresponding deterministic (homogeneous soil) case. In addition, differential settlements are computed in the stochastic analysis, something impossible in a deterministic analysis of a symmetric problem. A parametric study is performed to investigate the effects of various probabilistic parameters involved in the problem. It is found that the coefficient of variation and the correlation length of the soil's shear strength (both controlling the amount of loose pockets in the soil mass) are the two most important parameters in variation of the bearing capacity and producing substantial differential settlements in heterogeneous soils compared to homogeneous soils.
Application of Fragility Curves in Operational Flood Risk Assessment
Authors: Wojciechowska K.  , Pleijter G.  , Zethof M.  , Havinga F.J.  , van Haaren D.H.  , Ter Horst W.L.A.
Published: February 2025

The aim of this article is to present and discuss fragility curves that were derived for numerous dikes in the Netherlands within the Dike Data Service Centre (DDSC) initiative. A fragility curve of a dike is a mapping from the set of loads, acting on the dike, to the set of conditional dike failure probabilities. The DDSC is a platform around a database for measurements related to water defences in the Netherlands. The measurements include real-time and historical data such as height measurements, pore water pressures, temperature etc. Besides the database functionality, the DDSC can be applied to interpret the information and issue warnings. The fragility curves were derived for failure mechanisms overtopping, piping and macro-stability as well as for combination of these mechanisms. Also, application of the fragility curves is addressed. The application includes: (i) insight into the effect of reducing uncertainties in subsoil-related parameters on the dike's reliability, (ii) derivation of the actual flooding probability and the actual local mortality risk, and (iii) prioritization of emergency flood measures. The derived fragility curves are conform findings of past studies: for water levels lower than the dike height, piping and macro-stability play an important role. Furthermore, the fragility curves prove to have an added value in operational flood risk assessment.
Evaluation of Differential Settlement along Bridge Approach Structure on Soft Bangkok Clay
Authors: Seawsirikul Sorasak  , Chantawarangul Korchoke  , Vardhanabhuti Barames
Published: February 2025

Excessive differential settlement along bridge approach is commonly found in the lower central region of Thailand. To overcome the differential settlement problem, engineers have developed different types of bridge approach structure and improved design procedures. Two types of bridge approach structure are currently used in Thailand, including the approach slab on ground and the approach slab on pile. This research conducts field investigation, subsoil exploration and laboratory testing, and long-term geotechnical instrumentation and monitoring program of two bridge approaches which were constructed in Bangkok and vicinity. After construction for 3 to 7 years, the study results show that the main cause of differential settlement along bridge approach is due to the foundation of bridge approach structure is rest on different soil layers having much different compressibility properties and thickness. The differential settlement problem is found at locations where the bridge approach foundation changes from end bearing pile to friction pile, and to shallow foundation. The long-term observations show that the differential settlement could cause a sudden change in the longitudinal slope and discomfort driver. Moreover, it could create large voids underneath the approach slab, failure of concrete slab, and damage of pavement and structure members along bridge approach. Back analysis results show that the settlement prediction using the Terzaghi consolidation theory and elastic theory with equivalent foundation approach for vertical stress distribution gives 0.44 to 1 times the value observed in the field.
Probabilistic Slope Stability Analyses Using Limit Equilibrium and Finite Element Methods
Authors: Akbas Burak  , Huvaj Nejan
Published: February 2025

This paper compares the results of different probabilistic approaches and emphasizes the necessity of probabilistic analyses in slope stability studies. To do that, Limit Equilibrium Method (LEM) and Finite Element Method (FEM) are utilized and their outputs are compared in terms of probability of failure (PF), reliability index (RI), factor of safety (FS) and the failure surface. Lastly, concept of Random Finite Element Method (RFEM) is studied and effects of spatial correlation distance are investigated.
Eight Things Successful Geotechnical Risk Managers Do
Authors: Smits E.P.T.
Published: February 2025

Looking back over a period of 10 years of underground works, geotechnical risk management has matured and has definitively contributed to the success of geotechnical projects in Rotterdam. But, what exactly was it that made geotechnical risk management successful? Looking back, and analysing the process, 8 habits of the (geotechnical) risk manager can be distinguished which made the Rotterdam approach successful.
Interpretation of CPTU Tests with Statistical and Geostatistical Methods
Authors: Spacagna Rose Line  , Fouquet Chantal de  , Russo Giacomo
Published: February 2025

In the paper statistical methods for the interpretation of CPT data for the definition of subsoil stratigraphy have been applied to a subsoil CPTU data set of the Italian Center of Aerospatial Research (CIRA) in Capua (Italy). Results obtained by following the method proposed by Wickremesinghe and Campanella (1991) have been compared with those obtained by a geostatistical method recently proposed by Spacagna (2014), based on the spatial variability analysis of CPTU data. The latter results showed a more detailed definition of the transitions between different subsoil layers along the investigated vertical axes.
Risk Management for the Underground Car Park Kruisplein
Authors: Allaart A.P.  , Portengen C.
Published: February 2025

In the preparation and construction stages of the underground car park beneath Kruisplein with diaphragm walls, risk management played an important role. After a description of the structure and the construction, the preventive measures that were invented and carried out are summarised. These relate to the organisation of the project (experienced advisors, consequent risk management), the preparation of the construction stage (detailed plan of action, lessons learned from other projects, analysis of the environment and physical conditions), environment management, monitoring and the supervision of the construction process. The monitoring process and a new method to detect anomalies in the joints of diaphragm walls are presented in more detail.
Interpretation of CPTU Tests with Statistical and Geostatistical Methods
Authors: Spacagna Rose Line  , de Fouquet Chantal  , Russo Giacomo
Published: February 2025

In the paper statistical methods for the interpretation of CPT data for the definition of subsoil stratigraphy have been applied to a subsoil CPTU data set of the Italian Center of Aerospatial Research (CIRA) in Capua (Italy). Results obtained by following the method proposed by Wickremesinghe and Campanella (1991) have been compared with those obtained by a geostatistical method recently proposed by Spacagna (2014), based on the spatial variability analysis of CPTU data. The latter results showed a more detailed definition of the transitions between different subsoil layers along the investigated vertical axes.
Considering Parameter Uncertainty in a GIS-Based Sliding Surface Model for Large Areas
Authors: Mergili Martin  , Marchesini Ivan  , Rossi Mauro  , Alvioli Massimiliano  , Schneider-Muntau Barbara  , Cardinali Mauro  , Ardizzone Francesca  , Fiorucci Federica  , Valigi Daniela  , Santangelo Michele  , Bucci Francesco  , Guzzetti Fausto
Published: February 2025

The GIS-based open source software r.slope.stability computes broad-scale spatial overviews of shallow and deep-seated slope stability through physically-based modelling. We focus on the landslide-prone 90 km2Collazzone area, central Italy, exploiting a comprehensive set of lithological, geotechnical and landslide inventory data available for that area. Inevitably, the geotechnical and geometric parameters are uncertain, particularly for their three-dimensional variability. Considering the most unfavourable set of geotechnical parameters (worst case scenario, appropriate for engineering purposes) is less useful to obtain an overview of the spatial probability (susceptibility) of landslides over tens of square kilometres. Back-calculation of the parameters based on topographic and geotechnical considerations would better suit for such a purpose, but obtaining one single parameter combination would require information on one of the parameters. Instead, we estimate the slope failure probability by testing multiple combinations of the model parameters sampled deterministically. Our tests indicate that (i) the geotechnical parameterization used allows to reproduce the observed landslide distribution partly (a challenge consists in the appropriate treatment of the variation of the geotechnical parameters with depth); (ii) the evaluation outcome depends strongly on the level of geographical aggregation; and (iii) when applied to large study areas, the approach is computing-intensive, and requires specific strategies of multi-core computing to keep computational times at an acceptable level.
Giant Steps in Jazz Practice with the Social Virtual Band
Authors: Ramona Mathieu  , Pachet François  , Gorlow Stanislaw
Published: February 2025

This chapter deals with the issue of learning how to improvize. Traditional MOOCs provide jazz students with comprehensive theoretical and motivate students to practice intensively on their own. However, without a view of one's progress, and without feedback, individual practice is a long and winding road along which many students get lost. Indeed, most jazz learning systems lack these two crucial ingredients, resulting in high drop-out rates. This chapter addresses the issue of designing tools for supporting improvisation practice by bringing in a social dimension enabling peer-to-peer feedback, as well as a cloud-based infrastructure enabling arbitrary vizualisations of the evolution of the student performance. We introduce Social Virtual Band, a system that lets learners improvize solos on dynamically created accompaniments, and that records and archives all the training sessions along with the provided accompaniments on the cloud. Simple automatic feedback is presented to measure the evolution of his skills, based on a comparison between played note with scales obtained from automatic harmonic analysis. We describe the overall infrastructure underlying such a tool and discuss how such infrastructure opens up new possibilities for learning music.
Steps Towards Intelligent MOOCs:
Authors: Beuls Katrien  , Loeckx Johan
Published: February 2025

Despite their overwhelming success, present-day Massive Open Online Courses are far removed from the student modelling capacities displayed by earlier Intelligent Tutoring Systems. Being mere content delivery tools, MOOCs typically lack a thorough assessment module as well as tools for personalising the learner's track. When learning music, particularly, these two properties are indispensable. This chapter surveys suggestions made by experts in the field of AI in education today towards the incorporation of ITS tools and techniques into MOOCs. Yet, more traditional student models and tutoring modules are not without shortcomings themselves and the real challenge lies in making active models of both the tutor and the student, which can be used to predict future learning tracks and set the right challenges. Agent-based tutoring systems offer an attractive framework for building such active tutor/student models. The proposed concepts are illustrated in the domain of music composition. A tutoring system has been implemented to teach students the craft of counterpoint, a commonly used strategy for learning polyphonic music composition. It is based on the theory of flow to keep students motivated and optimize learning.
Collaborative Peer Assessment using PeerLearn
Authors: Brito Ismel  , Gutierrez Patricia  , Hazelden Katina  , de Jonge Dave  , Lemus Lisette  , Osman Nardine  , Rosell Bruno  , Sierra Carles  , Roig Carme
Published: February 2025

In this chapter we introduce the PeerLearn methodology and its associated tools. We base the design of pedagogical workflows for students on the definition of rubrics (using PeerAssess) as the starting element that drives the creation of lesson plans (using LessonEditor). These plans run over our web platform (Peer-Flow). Students can evaluate one another following given rubrics and teachers can accept (or not) marks produced by a collaborative assessment tool (COMAS). Experimental results show that PeerLearn provide students with a highly satisfying new pedagogical experience and increased learning outcomes.