Infrastructures

41 pages, 15385 KiB

Open AccessArticle

Investigation of the Geometrical Deterioration of Paved Superstructure Tramway Tracks in Budapest (Hungary)

by Vivien Jóvér, Zoltán Major, Attila Németh, Dmytro Kurhan, Mykola Sysyn and Szabolcs Fischer

Infrastructures 2023, 8(8), 126; https://doi.org/10.3390/infrastructures8080126 - 14 Aug 2023

Cited by 1 | Viewed by 1218

In the 21st century, one of the key requirements is to develop and maintain our infrastructure facilities most efficiently using the available resources. Tramways are of significant national economic importance and represent an important national asset. There are currently seven different types of [...] Read more.

In the 21st century, one of the key requirements is to develop and maintain our infrastructure facilities most efficiently using the available resources. Tramways are of significant national economic importance and represent an important national asset. There are currently seven different types of superstructure systems in Hungary, based on the national regulations and the related requirements currently in force. This paper compares the paved tramway superstructure systems in the context of track geometry, through-rolled axle tons of track, and the age of track sections. Paved tracks have many benefits, but the main ones are easier maintenance and road traffic use. Elastically supported continuous rail bedding (ESCRB; in Hungary, this is known as “RAFS”) and “large” slab superstructure systems are used to create paved superstructure systems. Road crossings use the latter systems, while heavily loaded lines use several ESCRB systems. This article examines the geometrical changes in several ESCRB superstructure systems. A TrackScan 4.01 instrument was used to take measurements in June and September 2021 and in April 2022, September 2022, and May 2023. Track gauge, alignment, and longitudinal level are examined. Regardless of the ESCRB superstructure system or age, a medium-loaded line’s track gauge trendline increases, which means that the track gauge is widening and, regardless of traffic load or age, the average longitudinal level is constantly increasing from year to year. When it is a medium-loaded line, the average value of alignment increases slightly, and the trendline is almost straight, but it decreases when it is an extremely heavily loaded line. The authors will analyze how the reference track section will change in the future. Based on the results, it is important to assess how subsequent measurements affect the trend lines. Because the data evaluations show similar results, comparing open tramway tracks to paved ones is crucial. Full article

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20 pages, 2626 KiB

Open AccessArticle

Soft Computing to Predict Earthquake-Induced Soil Liquefaction via CPT Results

by Ali Reza Ghanizadeh, Ahmad Aziminejad, Panagiotis G. Asteris and Danial Jahed Armaghani

Infrastructures 2023, 8(8), 125; https://doi.org/10.3390/infrastructures8080125 - 14 Aug 2023

Cited by 1 | Viewed by 1203

Abstract

Earthquake-induced soil liquefaction (EISL) can cause significant damage to structures, facilities, and vital urban arteries. Thus, the accurate prediction of EISL is a challenge for geotechnical engineers in mitigating irreparable loss to buildings and human lives. This research aims to propose a binary [...] Read more.

Earthquake-induced soil liquefaction (EISL) can cause significant damage to structures, facilities, and vital urban arteries. Thus, the accurate prediction of EISL is a challenge for geotechnical engineers in mitigating irreparable loss to buildings and human lives. This research aims to propose a binary classification model based on the hybrid method of a wavelet neural network (WNN) and particle swarm optimization (PSO) to predict EISL based on cone penetration test (CPT) results. To this end, a well-known dataset consisting of 109 datapoints has been used. The developed WNN-PSO model can predict liquefaction with an overall accuracy of 99.09% based on seven input variables, including total vertical stress (

σ_{v}

), effective vertical stress (

σ_{v}^{'}

), mean grain size (D₅₀), normalized peak horizontal acceleration at ground surface (α_max), cone resistance (q_c), cyclic stress ratio (CSR), and earthquake magnitude (M_w). The results show that the proposed WNN-PSO model has superior performance against other computational intelligence models. The results of sensitivity analysis using the neighborhood component analysis (NCA) method reveal that among the seven input variables, q_c has the highest degree of importance and M_w has the lowest degree of importance in predicting EISL. Full article

(This article belongs to the Special Issue Geotechnical Earthquake Engineering)

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23 pages, 11462 KiB

Open AccessArticle

Parametric Investigation of Interaction between Soil-Surface Structure and Twin Tunnel Excavation: A Comprehensive 2D Numerical Study

by Ammar Alnmr, Ashraf Sheble, Richard Ray and Hussein Ahmad

Infrastructures 2023, 8(8), 124; https://doi.org/10.3390/infrastructures8080124 - 11 Aug 2023

Cited by 2 | Viewed by 1149

Abstract

The growing demand for transportation tunnels in densely populated urban areas has led to the widespread adoption of twin tunnel configurations in contemporary infrastructure projects. This research focuses on investigating the complex interaction between soil, structures, and the excavation of twin tunnels. The [...] Read more.

The growing demand for transportation tunnels in densely populated urban areas has led to the widespread adoption of twin tunnel configurations in contemporary infrastructure projects. This research focuses on investigating the complex interaction between soil, structures, and the excavation of twin tunnels. The study employs the tunnel boring machine (TBM) method and utilizes two-dimensional numerical modeling based on the finite element method (FEM). The numerical model is validated by comparing its results with field measurements obtained from a twin tunnel project in Italy, specifically the New Milan Metro Line 5. A comprehensive parametric study is conducted to analyze various parameters that influence soil–structure interaction during tunnel excavation. These parameters include the positioning of the tunnels in relation to each other, the spacing between them, the presence of structures above the tunnels, eccentricity between the structure axis and tunnel axis, and tunnel depth and diameter. Moreover, a comparative analysis is performed between scenarios with and without structures to elucidate the impact of structure presence on the interaction phenomenon. The research findings provide valuable insights into the intricate behavior of twin tunnels and their interaction with the surrounding soil and structures. Full article

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13 pages, 4099 KiB

Open AccessArticle

A Model Classifying Four Classes of Defects in Reinforced Concrete Bridge Elements Using Convolutional Neural Networks

by Roman Trach

Infrastructures 2023, 8(8), 123; https://doi.org/10.3390/infrastructures8080123 - 11 Aug 2023

Cited by 1 | Viewed by 1061

Abstract

Recently, the bridge infrastructure in Ukraine has faced the problem of having a significant number of damaged bridges. It is obvious that the repair and restoration of bridges should be preceded by a procedure consisting of visual inspection and evaluation of the technical [...] Read more.

Recently, the bridge infrastructure in Ukraine has faced the problem of having a significant number of damaged bridges. It is obvious that the repair and restoration of bridges should be preceded by a procedure consisting of visual inspection and evaluation of the technical condition. The problem of fast and high-quality collection, processing and storing large datasets is gaining more and more relevance. An effective way to solve this problem is to use various machine learning methods in bridge infrastructure management. The purpose of this study was to create a model based on convolutional neural networks (CNNs) for classifying images of concrete bridge elements into four classes: “defect free”, “crack”, “spalling” and “popout”. The eight CNN models were created and used to conduct its training, validation and testing. In general, it can be stated that all CNN models showed high performance. The analysis of loss function (categorical cross-entropy) and quality measure (accuracy) showed that the model on the MobileNet architecture has optimal values (loss, 0.0264, and accuracy, 94.61%). This model can be used further without retraining, and it can classify images on datasets that it has not yet “seen”. Practical use of such a model allows for the identification of three damage types. Full article

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16 pages, 2729 KiB

Open AccessArticle

Structural Pounding Effect on the Seismic Performance of a Multistorey Reinforced Concrete Frame Structure

by Kosmas E. Bantilas, Maria C. Naoum, Ioannis E. Kavvadias, Chris G. Karayannis and Anaxagoras Elenas

Infrastructures 2023, 8(8), 122; https://doi.org/10.3390/infrastructures8080122 - 02 Aug 2023

Cited by 1 | Viewed by 1808

Abstract

During intense ground motion excitations, the pounding between adjacent buildings may result in extensive structural damage. Despite the provision of regulations regarding the minimum separation gap required to prevent structural collisions, the majority of existing structures are poorly separated. The modern seismic design [...] Read more.

During intense ground motion excitations, the pounding between adjacent buildings may result in extensive structural damage. Despite the provision of regulations regarding the minimum separation gap required to prevent structural collisions, the majority of existing structures are poorly separated. The modern seismic design and assessment of structures are based on the definition of acceptable response levels in relation to the intensity of seismic action, which is usually determined by an acceptable probability of exceedance. From this point of view, the seismic performance of a typical eight-storey reinforced concrete (RC) frame structure is evaluated in terms of pounding. In particular, the performance is evaluated using six different separation gap distances as a fraction of the EC8 minimum distance. As the height of the adjacent structure affected the required separation distance, the examined RC structure was assumed to interact with four idealized rigid structures of one to four storeys. The typical storey height was equal between the examined structures; therefore, collision could occur at the diaphragm level. To this end, incidental dynamic analyses (IDAs) were performed, and the fragility curves for different limit states were obtained for each case. Finally, the seismic fragility was combined with the hazard data to evaluate the seismic performance probabilistically. Full article

(This article belongs to the Special Issue Advances in Structural Dynamics and Earthquake Engineering)

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15 pages, 4927 KiB

Open AccessArticle

Electrification of Transport Service Applied to Massawa–Asmara

by Cristian Giovanni Colombo, Alessandro Saldarini, Michela Longo, Wahiba Yaici, Fabio Borghetti and Morris Brenna

Infrastructures 2023, 8(8), 121; https://doi.org/10.3390/infrastructures8080121 - 01 Aug 2023

Viewed by 1341

Abstract

Considering the proposed strict new constraints of public authorities, decarbonization has become a key trend in recent years. Although several countries have started the process of decarbonization through the introduction of electric vehicles in their public services, for many countries, especially developing countries, [...] Read more.

Considering the proposed strict new constraints of public authorities, decarbonization has become a key trend in recent years. Although several countries have started the process of decarbonization through the introduction of electric vehicles in their public services, for many countries, especially developing countries, transportation is still a hard sector to decarbonize. The presence of obsolete and polluting vehicles discourages citizens from using public transport and thus incentivizes the use of private vehicles, which create traffic congestion and increase emissions. Based on these considerations, this paper aimed to implement a simulation for a public service in Eritrea, evaluating whether it is possible to take a long trip using an electric minibus. A case study is implemented highlighting the barriers of electrifying transportation in this area, producing results on fuel consumption and service reliability. In the case study, four scenarios are presented to estimate the service. The scenarios evaluate the possibility to perform from three to five recharges. Fewer charges mean longer charging time, leading to a 2 h charging phase in Scenario 1, while recharging more than twice along the route will lead to shorter 30 min charges, as in Scenario 3. The case study also highlights the relevance of the slope in electric vehicle performance, as reported for the case of Asmara–Massawa travel (

E_{c o n s} =

6.688 kWh). Finally, an environmentally sustainable solution, such as a 92 kWh/day photovoltaic plant, is proposed to power the service. Full article

(This article belongs to the Special Issue Smart Mobility: Advancements and Innovations in Intelligent Transportation Systems)

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23 pages, 5297 KiB

Open AccessArticle

Improved Alkali–Silica Reaction Forecast in Concrete Infrastructures through Stochastic Climate Change Impact Analysis

by Md Asif Rahman and Yang Lu

Infrastructures 2023, 8(8), 120; https://doi.org/10.3390/infrastructures8080120 - 31 Jul 2023

Viewed by 1373

Abstract

The assessment of concrete infrastructures’ functionality during natural hazards is fundamental in evaluating their performance and emergency response. In this work, the alkali–silica reaction (ASR) in concrete is evaluated under the climate change impact. The ASR is greatly influenced by the weather parameters, [...] Read more.

The assessment of concrete infrastructures’ functionality during natural hazards is fundamental in evaluating their performance and emergency response. In this work, the alkali–silica reaction (ASR) in concrete is evaluated under the climate change impact. The ASR is greatly influenced by the weather parameters, such as temperature and humidity. Climate change has led the quickening of global warming and has caused extreme weather events in recent years. These events can create anomalies in weather and thus convey potential threats to the concrete infrastructures affected by the ASR. Capturing these extreme events is the key prerequisite for the precise quantification of the ASR chemophysics. This work develops a novel stochastic approach to understand the influence of stochastic temperature and humidity on ASR expansion. To assess the stochastic weather impacts on concrete, a physics-informed domain is developed by capturing the variably saturated porous medium of concrete. This is an effort to analyze ASR kinetics that integrates chemo-physical damage under extreme weather events. Results elucidate that the ASR-affected concrete would experience 83.33% more damage in 10 years than from seasonal change due to the stochastic weather impacts from climate change. This improved predictive model will guide the durable infrastructure materials design practices and enhance the resiliency of concrete infrastructures. Full article

(This article belongs to the Special Issue Resilience of Infrastructures to Natural Hazards)

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9 pages, 3507 KiB

Open AccessCommunication

Wander Effect on Pavement Performance for Application in Connected and Autonomous Vehicles

by Jorge Pais, Paulo Pereira and Liseane Thives

Infrastructures 2023, 8(8), 119; https://doi.org/10.3390/infrastructures8080119 - 31 Jul 2023

Viewed by 1178

Abstract

Connected and Autonomous Vehicles (CAV) will change how road engineers design road pavements because they can position themselves within a traffic lane, keeping their position in the lane more precisely than human-driven vehicles. These vehicles will have lower lateral wandering, which can induce [...] Read more.

Connected and Autonomous Vehicles (CAV) will change how road engineers design road pavements because they can position themselves within a traffic lane, keeping their position in the lane more precisely than human-driven vehicles. These vehicles will have lower lateral wandering, which can induce more damage to pavements, such as cracking and permanent deformation, than the conventional vehicles, with consequences for the infrastructures due to the increased cracking and reduced safety due to the rutting. Thus, it is essential to assess the wander effect on pavement performance to define policies for its implementation on CAV. This paper studies the impact of the lateral wander of the traffic on pavement performance, considering its fatigue and permanent deformation resistance. This impact can be used to define limits for the wander to minimize distresses on the pavement. The results of this study allow us to conclude that for a pavement with a 10 cm asphalt layer, the wander effect is more significant for fatigue life. A pavement life increase of 20% was observed for a wander of 0.2 m, while for 0.6 m, the fatigue life can increase up to 48%. For the permanent deformation, a pavement life increase of 2% for a wander of 0.2 m was observed, but for 0.6 m, the pavement life can be increased up to 34%. Full article

(This article belongs to the Special Issue Selected Papers from the 5th International Conference on Transportation Infrastructures Conference)

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12 pages, 2100 KiB

Open AccessArticle

Asset Valuation Model for Highway Rigid Pavements Applicable in Public–Private Partnerships Projects

by Luis Arce, Rodrigo Delgadillo, Alelí Osorio-Lird, Felipe Araya and Carlos Wahr

Infrastructures 2023, 8(8), 118; https://doi.org/10.3390/infrastructures8080118 - 30 Jul 2023

Viewed by 1275

Abstract

Recently, in Chile, infrastructure asset value has been incorporated into highway concession contracts. However, the current valuation model used for rigid pavements is not adapted to the standards and conditions of such projects. This study develops a valuation model for rigid pavements of [...] Read more.

Recently, in Chile, infrastructure asset value has been incorporated into highway concession contracts. However, the current valuation model used for rigid pavements is not adapted to the standards and conditions of such projects. This study develops a valuation model for rigid pavements of interurban highway concessions and evaluates it in a case study. The proposed model captures the loss in asset value associated with the performance degradation over time, considering a typical Jointed Plain Concrete Pavement (JCPC) configuration. The value is calculated using performance indicators that represent the structural capacity and level of service provided to road users. The model represents a significant improvement compared to current asset valuation models used in highway concessions. It enables the public agency to objectively evaluate the preservation of asset value carried out by the private partner during the concession. Additionally, it could also be used as a tool to establish payments between infrastructure stakeholders. Some of the concepts applied could also be relevant for other highway assets existing in Public–Private Partnership (PPP) projects. Full article

(This article belongs to the Special Issue Selected Papers from the 5th International Conference on Transportation Infrastructures Conference)

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17 pages, 2522 KiB

Open AccessArticle

Effect of Coarse Aggregate Grading on Mechanical Parameters and Fracture Toughness of Limestone Concrete

by Grzegorz Ludwik Golewski

Infrastructures 2023, 8(8), 117; https://doi.org/10.3390/infrastructures8080117 - 27 Jul 2023

Cited by 11 | Viewed by 1127

Abstract

This work presents a discussion of the basic properties of broken mineral limestone aggregates with the specification of the properties affecting the fracture toughness of concretes made with these aggregates. To determine the influence of the grain-size distribution of coarse aggregates for each [...] Read more.

This work presents a discussion of the basic properties of broken mineral limestone aggregates with the specification of the properties affecting the fracture toughness of concretes made with these aggregates. To determine the influence of the grain-size distribution of coarse aggregates for each concrete series, two types of aggregate grain were used, with maximum grain sizes of 8 mm (series of concrete L1) and 16 mm (series of concrete L2). Fracture-toughness tests were carried out using mode I fractures in accordance with the RILEM Draft recommendations, TC-89 FMT. During the experiments the critical stress-intensity factor

(K_{I c}^{S})

and crack-tip-opening displacements (

C T O D c

) were determined. The main mechanical parameters, i.e., the compressive strength (f_cm) and splitting tensile strength (f_ctm), were also assessed. Based on the obtained results, it was found that the grain-size distribution of the limestone aggregate influenced the concrete’s mechanical and fracture-mechanics parameters. The obtained results showed that the series-L2 concrete had higher strength and fracture-mechanics parameters, i.e.,: f_cm—45.06 MPa, f_ctm—3.03 MPa,

K_{I c}^{S}

—1.22 MN/m^3/2, and

C T O D c

—12.87 m10⁻⁶. However, the concrete with a maximum grain size of 8 mm (series of concrete L1) presented lower values for all the analyzed parameters, i.e.,: f_cm—39.17 MPa, f_ctm—2.57 MPa,

K_{I c}^{S}

—0.99 MN/m^3/2, and

C T O D c

—10.02 m10⁻⁶. The main reason for the lower fracture toughness of the concretes with smaller grain sizes was the weakness of the ITZ in this composite compared to the ITZ in the concrete with a maximum grain size of 16 mm. The obtained test results can help designers, concrete producers, and contractors working with concrete structures to ensure the more conscious composition of concrete mixes with limestone aggregates, as well as to produce precise forecasts for the operational properties of concrete composites containing fillers obtained from carbonate rocks. Full article

(This article belongs to the Special Issue Advanced Structural Analysis of Masonry and Reinforced Concrete Structures)

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Infrastructures, Volume 8, Issue 8 (August 2023) – 10 articles

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