Procter & Gamble (United Kingdom)
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Senzori kao deo digitalnih blizanaca kanalizacionih sistema: specifičnosti mernih metoda i mogućnosti primene pristupačnih rešenja
No full text— Uloga kanalizacionih sistema, kao dela komunalne
infrastrukture, je da bezbedno sprovode upotrebljene i
atmosferske vode sa urbanih slivova, bez prekida u radu. Jedan od
pristupa koji se razvija poslednjih godina, a koji potencijalno može
značajno da unapredi rad ovih sistema je primena digitalnih
blizanaca. Sastavni element digitalnih blizanaca je i adekvatno
prostorno raspoređena senzorska mreža, koja omogućava
praćenje merodavnih hidrauličkih veličina u realnom vremenu.
Nažalost, imajući u vidu specifičnosti rada ovih sistema i visoku
cenu profesionalne merne opreme, najčešće ovakvih senzora nema
dovoljno. U ovom radu je dat osvrt na specifičnosti mernih metoda
koje se koriste u kanalizacionim sistemima, odnosno njihovim
prednostima i manama. Analizirana su i alternativna rešenja u
vidu pristupačnih senzora, gde je posebno apostrofirano rešenje
koje se razvija na Institutu za hidrotehniku koje se bazira na
primeni videometrijskih metoda. Taksativno su navedeni i posebni
uslovi koja sva merna oprema koja se koristi u kanalizaciji, mora
da zadovolji
Assessment of Concrete and Reinforced Concrete Beams Incorporating CRT Panel Glass Using Non-Destructive and Destructive Testing Methods
No full textThis study examines the feasibility of incorporating cathode-ray tube (CRT) panel glass as a partial replacement of natural aggregate in concrete, aiming to promote sustainable material utilization without compromising structural performance. Nine mixtures were prepared using three cement types—Normal 42.5 N, PC 50M(S-V-L) 42.5 N; Profi 42.5 R, PC 20M(S-L) 42.5 R; and Cement without additions, CEM I 42.5 R—and three CRT contents (0%, 5%, and 10%). A comprehensive experimental program was conducted, including tests on natural aggregates, mortars, and concrete in both fresh and hardened states, as well as flexural testing of reinforced concrete beams, supported by ground-penetrating radar (GPR) and digital image correlation (DIC) measurements. The results revealed that replacing up to 5% of natural aggregate with CRT glass had negligible effects on workability and density while slightly improving compressive and flexural strength. At 10% replacement, a minor reduction in strength and ductility was observed. Durability-related parameters, such as water absorption and carbonation depth, increased slightly but remained within acceptable limits. Flexural tests confirmed that beams with 5% CRT content exhibited comparable load capacity and crack propagation to reference beams. This study represents the first combined application of Digital Image Correlation (DIC) and Ground-Penetrating Radar (GPR) in evaluating reinforced concrete beams with CRT-modified concrete across different cement types. The results showed that incorporating 5% CRT glass increased flexural tensile strength by up to 15% compared with the control mix, confirming both the structural feasibility and sustainability of such composites. Overall, the findings indicate that CRT panel glass can be effectively utilized up to a 5% replacement level, offering both environmental and structural advantages for sustainable concrete production. Based on the experimental results, a replacement level of up to 5% CRT glass is recommended for structural concrete applications under the tested conditions, where CRT particles replaced the 4–8 mm medium aggregate fraction, as it ensures a balance between strength, ductility, and durability
Digital Twins of Urban Drainage Systems: ML-assisted algorithm for processing sensor data
No full textDeploying sensors network and collecting and using sensor data is a backbone of Digital Twins (DTs) for engineering systems, such as Urban Drainage Systems (UDS). Such data often exhibit missing values and anomalous readings due to many factors (e.g. sensors malfunction, hardware limitations, weather and site conditions). System analytics in DTs rely on these data and requires postprocessing algorithms capable to detect and reduce problems in collected data. This research aims to develop an advanced ML-powered algorithm for automated data anomaly detection (data validation) and estimation of missing data. This algorithm utilizes an ensemble of ML models to address data quality issues. The algorithm is tested on a synthetic dataset for a part of Belgrade stormwater system
Dependency of Fatigue Resistance on Roughness in Wire Arc Additively Manufactured Carbon Steel Components
No full textThe fatigue resistance of rough components produced by wire-arc additive manufacturing (WAAM) is highly sensitive to geometric discontinuities as sur-face undulations contribute to stress concentration where fatigue cracks initi-ate. This research investigates the fatigue resistance of WAAM plates made of S355 carbon steel by combining fatigue experiments on samples character-ised by different roughness and finite element (FE) models. The experiments evaluated the fatigue lives of a range of rough specimens under constant amplitude cyclic loading. The as-deposited surfaces were measured with high precision three-dimensional laser scanning. A generalised notch stress (GNS) approach estimating the fatigue resistance of as-deposited specimens is then developed. Based on parametric FE assessment, different surface roughness is studied and their influence on the fatigue resistance is computed, highlight-ing key correlations between the ten-point roughness height and the fatigue strength
Addressing aquaplaning challenges on wide motorway pavements: A review of pavement superelevation methods in poorly drained zones
No full textThe effective drainage of motorway pavements is of the utmost importance for ensuring road safety and the longterm durability of the pavement structure. Motorway sections with inadequate drainage exhibit accelerated deterioration, necessitating increased investments for rehabilitation or reconstruction. Inflection zones on motorways constructed in flat terrain are especially prone to aquaplaning (or hydroplaning). In such topographically favourable conditions, the motorway's horizontal geometry, typically comprising large circular and transition curves, is
combined with shallow longitudinal grades dictated by the flat terrain. As a result, in the motorway inflection zones both cross and longitudinal grades are close to zero, thus producing poorly drained pavement surfaces with increased water film depths. This issue is exacerbated with an increase in the number of driving lanes or the overall width of the motorway cross-section. To reduce poorly drained pavement areas in motorway inflection zones, national road authorities across Europe use different measures against aquaplaning. These measures encompass the construction of porous asphalt as the pavement wearing course, increase in longitudinal grades, implementation of special superelevation methods - such as crowned pavement and variable pavement superelevation along reverse curves, occasional application of "negative" pavement cross grades in curves of extremely large radii (thus avoiding superelevation et all) and the incorporation of additional construction measures, such as transverse gutters set across the roadway. This paper primarily addresses superelevation methods that could be applied for aquaplaning risk mitigation in motorway inflection zones in light of anticipated climate changes that may impact road infrastructure across European countries
Prirodom inspirisana rešenja u urbanom odvodnjavanju: mogućnosti i izazovi poroznog popločanja
No full textUrbane sredine suočavaju se sa sve učestalijim pluvijalnim poplavama usled klimatskih promena i sve većeg udela nepropusnih površina. Tradicionalni sistemi kanalizacije često ne mogu efikasno da prihvate uvećane velike količine atmosferskih otpadnih voda, što dovodi do izlivanja vode u
najnižim etažama objekata, zadržavanja vode na terenu i potencijalne kontaminacije prostora. Primena prirodom inspirisanih rešenja, poput poroznih betonskih popločanja, omogućava kontrolisanu infiltraciju i retenziranje atmosferskih voda, smanjujući vršne protoke, zapreminu otekle vode i povećavajući trajnost infrastrukture. Integracija prirodom inspirisanim rešenja i sive infrastrukture vodi ka uvećanom korišćenju recikliranih materijala što održivosti i rezilijentnosti urbanih sredina prema pluvjalnim poplavama
Development of a Hybrid Model for Risk Assessment and Management in Complex Road Infrastructure Projects
No full textDuring the execution of road infrastructure projects, project managers face significant challenges, including financial, technical, regulatory, and operational risks. More than 90% of infrastructure projects have incurred costs exceeding initial estimates, impacting both completion timelines and the operational efficiency of road infrastructure. Effectively assessing and managing these risks is crucial for improving project outcomes and ensuring the sustainability of infrastructure investments. To address these challenges, this study developed a hybrid model for risk assessment and management in road infrastructure projects. The model quantifies risks across seven key categories: Design, External, Resource, Employer, Contractor, Engineer, and Project, based on three primary input factors: Environment coefficient, Contractual coefficient, and Design coefficient. Initially, various machine learning models, including linear regression, Random Forest, Gradient Boosting, Stacking Models, and neural networks, were applied to assess risk predictions. However, due to the specific nature of the dataset, these models did not achieve satisfactory predictive accuracy. As a result, fuzzy logic systems (Mamdani and Sugeno) were employed, demonstrating superior performance in modeling risk occurrence probabilities. Comparative analysis between these two fuzzy logic approaches revealed that the Sugeno model provided the most accurate predictions. The findings highlight the benefits of applying fuzzy logic for risk assessment in complex infrastructure projects, providing a structured framework for enhancing decision-making processes. This study provides a structured methodology for accurately predicting risks and enhancing project safety, efficiency, and long-term sustainability
Experimental investigation of the influence of chemical admixtures on the basic properties of 3D printed concrete
No full textThis study analyzes the impact of chemical admixtures on the basic properties of 3D
printed concrete. The investigation was carried out using two commercial chemical admixtures, the
superplasticizer SikaViscoCrete®-5500 Iron and the hydration controller SikaTard®-930, both
manufactured by Sika. The experimental program included the testing of concrete properties in fresh
and hardened states, using four different mixtures (named A, B, C, and D), which were prepared by
varying the dosages of the used admixtures. The open time and extrudability were determined in the
fresh state for all mixtures, and the extrudability test was used as an indicator of the printability of the
concrete mixture. For selected mixtures (A and D), the bulk density and compressive strength was
tested at various ages on mold cast and 3D printed samples. Based on the obtained results, an
analysis of the impact of chemical admixtures was performed, highlighting the main conclusions
regarding the effects of admixtures on the basic properties of 3D printed concrete
ESE Framework for Rapid Post-earthquake Assessment of Repair Cost and Duration for Residential Buildings
No full textThis research advances the development of the RELA framework by introducing the ESE (El
ements-Severity-Extent) sub-framework for rapid post-earthquake repair cost and duration
estimation. Unlike fragility-based models relying on seismic intensity, ESE directly observes
damage, enabling deterministic repair assessments. Using a structured decision tree method
ology, ESE links observed damage to predefined repair methods, work items, and construc
tion norms to quantify materials and labour. Field inspectors document damage through a
spreadsheet-based tool, ensuring quick and reliable data collection. The system generates a
Repair Bill of Quantities for resource-constrained repair planning. Compared to FEMA P-58
PACT, ESE provides higher accuracy and real-world applicability. While PACT delivers rap
id probabilistic estimates, it lacks structured scheduling and resource-driven cost calcula
tions. On the contrary, ESE offers precise, implementable outputs to aid post-earthquake re
covery. A case study for masonry walls demonstrates ESE’s efficiency, highlighting the fa
vourable speed/accuracy/effort trade-off, as RELA-ESE requires low effort from non-expert
inspectors while providing accuracy comparable to a building-specific repair design. By
combining rapid assessment with structured planning, ESE delivers a fast, scalable, and pre
cise tool for disaster recovery. Real-time field validation will enhance its applicability
Prediction of free-edge stresses in composite laminates using full-layerwise-theory-based finite elements
No full textThis paper deals with the 3D analysis of free-edge stresses in laminated composite plates using Reddy’s full-layerwise-theory-based finite element model (FLWT-FEM). The theory assumes a piece-wise linear variation of all displacement components and quadratic variation of interlaminar stresses within each layer. The free-edge effects are related to singular stress states at the interfaces between dissimilar layers along the free edges of the laminar composite. Stress concentrations at free edges can further lead to delamination and the significant drop in stiffness, with failure occurring at lower loads than expected.
Starting from the strong formulation of the FLWT, a family of layered finite elements has been derived and implemented in original object-oriented MATLAB code. Free-edge stress field under axial strain has been analyzed. A validation example of cross-ply composite has been presented, and the results are compared against the existing analytical solutions and those obtained using the commercial software. The accuracy of the model is verified, and the possibilities for the further improvement and applications are provided