Infrastructures

23 pages, 8211 KiB

Open AccessArticle

Impact Assessment of Implementing Several Retrofitting Strategies on the Air-Conditioning Energy Demand of an Existing University Office Building in Santiago, Chile

by Tomás P. Venegas, Byron A. Espinosa, Francisco A. Cataño and Diego A. Vasco

Infrastructures 2023, 8(4), 80; https://doi.org/10.3390/infrastructures8040080 - 21 Apr 2023

Cited by 3 | Viewed by 1788

Abstract

This work analyzed the thermal behavior of an existing building, considering different retrofitting strategies. The methodology starts with an in-situ survey that allowed for obtaining information about occupation, work schedules, envelope materials, lighting, and equipment, which was vital to develop an energy model [...] Read more.

This work analyzed the thermal behavior of an existing building, considering different retrofitting strategies. The methodology starts with an in-situ survey that allowed for obtaining information about occupation, work schedules, envelope materials, lighting, and equipment, which was vital to develop an energy model of the building. Then, the thermal analysis, employing simulations, demonstrates a higher relevance of heat flows through the building’s envelope than internal loads and higher cooling rather than heating demands. Afterward, several retrofit strategies focusing on modifying architectural elements were assessed. Finally, these strategies were compared based on their impact on the air-conditioning energy demand. A systematic review identified a lack of studies relating certification and energy policies to buildings retrofitting. Therefore, we assessed the energy performance of the building, when modified to meet the baseline requirements set on the Chilean certification requirements for sustainable buildings, to verify if the certification is a suitable method to assess the energy efficiency of an office building. Although the study only involves a single building, it aims to illustrate identified limitations using the energy policies for Chilean public buildings. The Chilean certification for sustainable buildings seems not to be suitable for the evaluation of energy consumption for the retrofit of existing buildings. Although this study does not demonstrate general trends, it presents a precedent for subsequent studies to evaluate the relevance of the Chilean certification guidelines. Full article

(This article belongs to the Special Issue Smart, Sustainable and Resilient Infrastructures, 2nd Edition)

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Graphical abstract

15 pages, 3211 KiB

Open AccessArticle

Analysis of Road Users’ Risk Behaviors in Different Travel Modes: The Bangkok Metropolitan Region, Thailand

by Pawinee Iamtrakul, Sararad Chayphong, Emese Makó and Souvathone Phetoudom

Infrastructures 2023, 8(4), 79; https://doi.org/10.3390/infrastructures8040079 - 19 Apr 2023

Cited by 6 | Viewed by 1803

Abstract

This study explores road users’ behaviors and accident analyses on different travel modes in the Bangkok Metropolitan Region (BMR). The questionnaire survey was adopted and designed based on contributing factors related to risk behavior perceptions in different travel modes. A total of 3000 [...] Read more.

This study explores road users’ behaviors and accident analyses on different travel modes in the Bangkok Metropolitan Region (BMR). The questionnaire survey was adopted and designed based on contributing factors related to risk behavior perceptions in different travel modes. A total of 3000 participants submitted questionnaires that provided data for a multiple regression model analysis. The results indicated that different travel modes have different risk behavior perceptions. Road users of vulnerable modes of travel, such as walking and cycling, were more aware of risky behaviors than users of others. Risky, violent behavior may occur due to fatigue, driving while taking drugs, or aggressive tactics where the driver may lose control and cause an accident. However, driver negligence, especially violating traffic rules, may sometimes cause risky behavior. The results show that age, gender, education level, income level, marital status, driving experience, accident experience, and attitude toward road safety affect risk behavior perception. In conclusion, the differentiation of vehicles plays a vital role as a critical issue that should be understood for effectively mitigating risks in different travel patterns. Full article

(This article belongs to the Special Issue Land Transport, Vehicle and Railway Engineering)

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18 pages, 1952 KiB

Open AccessArticle

Quantitative Risk Assessment Model and Optimization in Infrastructure Fast-Track Construction Projects

by Claudia Garrido Martins, Susan M. Bogus and Vanessa Valentin

Infrastructures 2023, 8(4), 78; https://doi.org/10.3390/infrastructures8040078 - 18 Apr 2023

Cited by 2 | Viewed by 2088

Abstract

The construction industry has extensively applied the fast-tracking approach to the demanding need for the fast delivery of infrastructure projects. However, the fast-track strategy might be threatened by distinctive risks or changes in risk characteristics that emerge when activities are overlapped (overlapping risks). [...] Read more.

The construction industry has extensively applied the fast-tracking approach to the demanding need for the fast delivery of infrastructure projects. However, the fast-track strategy might be threatened by distinctive risks or changes in risk characteristics that emerge when activities are overlapped (overlapping risks). This article proposes a risk assessment simulation model to quantify the economic impact of overlapping risks on fast-track infrastructure projects. The model uses Monte Carlo simulation and a proprietary engine solution for the optimization procedure. It quantifies the overlapping risk impacts in the project duration and cost that could originate in three different overlapping degrees and evaluates the optimal overlapping degree to reduce the impact of the overlapping risks. The model demonstration used a commercial renovation project. The results suggest that overlapping risks have a high potential impact on the total cost, although with a high probability of attaining the target duration. Eight top risks affected the total duration, cost, or both. The optimum overlapping to reduce the economic impact and achieve the target project duration combines different overlapping degrees. This study contribution is a model for fast-track projects considering overlapping risks, their impact characteristic as a distribution, and the potential relationship between these risks. Full article

(This article belongs to the Special Issue Smart, Sustainable and Resilient Infrastructures, 2nd Edition)

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19 pages, 24357 KiB

Open AccessArticle

Estimation of Year of Construction of Bridges in Cambodia by Analyzing the Landsat Normalized Difference Water Index

by Eam Sovisoth, Vikas Singh Kuntal, Prakhar Misra, Wataru Takeuchi and Kohei Nagai

Infrastructures 2023, 8(4), 77; https://doi.org/10.3390/infrastructures8040077 - 13 Apr 2023

Cited by 2 | Viewed by 2043

Abstract

Inspection data can be used to comprehend and plan effective maintenance of bridges. In particular, the year of initial construction is one of the most important criteria for formulating maintenance plans, making budget allocations, and estimating soundness. In an initial survey of bridges [...] Read more.

Inspection data can be used to comprehend and plan effective maintenance of bridges. In particular, the year of initial construction is one of the most important criteria for formulating maintenance plans, making budget allocations, and estimating soundness. In an initial survey of bridges in Cambodia, it was concluded that the year of construction of only 54% of 2439 bridges surveyed is known, with the remaining 46% remaining unknown. In this research, Landsat satellite data is used to estimate the year of construction of these bridges. Landsat provides spatial spectral reflectance information covering more than 30 years, and for longer bridges this can be used to estimate the year of construction by visual judgement. However, limited image resolution means this is not possible for shorter bridges. Instead, a method using the Landsat Normalized Difference Water Index (NDWI) is used to estimate the year of construction. Three pixels are selected from Landsat image data in such a way that one lies on the current location of a bridge and two other reference pixels are placed on similar terrain at a certain distance perpendicular to the bridge axis. NDWI values are plotted over time for the three pixels and the difference in value between the bridge pixel and the two reference pixels is then compared. Before the bridge is constructed, all three pixels should have similar NDWI values, but after construction the value of the target bridge pixel should differ from the other two because the NDWI value of a bridge surface is different from that of the surrounding vegetation. By looking for this change, the year of construction of a bridge can be estimated. All the bridges in the Cambodian database are classified into three categories based on length (which affects their visibility in Landsat images) and year of construction is estimated. The results show that estimated year of construction has the same accuracy in all three categories. Full article

(This article belongs to the Topic Development of Monitoring, Analysis and Maintenance Technics of Infrastructures)

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16 pages, 1378 KiB

Open AccessReview

Interdependencies between Urban Transport, Water, and Solid Waste Infrastructure Systems

by Poornima A. Jayasinghe, Sybil Derrible and Lina Kattan

Infrastructures 2023, 8(4), 76; https://doi.org/10.3390/infrastructures8040076 - 12 Apr 2023

Cited by 3 | Viewed by 8116

Abstract

Developing integrated, sustainable, and resilient urban systems requires consideration of the different types of interdependencies between their infrastructure systems. The degree and nature of interdependencies among infrastructure systems vary widely. This article identifies and analyzes the interdependencies between urban transport, water, and solid [...] Read more.

Developing integrated, sustainable, and resilient urban systems requires consideration of the different types of interdependencies between their infrastructure systems. The degree and nature of interdependencies among infrastructure systems vary widely. This article identifies and analyzes the interdependencies between urban transport, water, and solid waste. A comprehensive review is conducted, an interdependency matrix for the three systems is developed, and the interdependencies are analyzed qualitatively. The analysis shows that the three systems are highly interdependent, indicating that an integrated approach that considers the mutual impacts, conflicts, and interactions among them at all stages of their life cycles is necessary to promote sustainability and resilience. This article also identifies opportunities for developing new integrated planning and design approaches and emphasizes the need for further research in this area to quantify infrastructure interdependencies. This is particularly important in the context of rapid urbanization and the pressure on cities to adapt to climate change. Full article

(This article belongs to the Section Sustainable Infrastructures)

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15 pages, 2822 KiB

Open AccessArticle

IIoT-Supported Manufacturing-Material-Flow Tracking in a DES-Based Digital-Twin Environment

by Gergő Dávid Monek and Szabolcs Fischer

Infrastructures 2023, 8(4), 75; https://doi.org/10.3390/infrastructures8040075 - 10 Apr 2023

Cited by 4 | Viewed by 1739

Abstract

Manufacturing processes can be cited as significant research areas when examining infrastructure systems and infrastructure, as they are inextricably linked to both. Examples include automobile manufacturing, the production of traffic signs, etc. Connecting and utilizing Industry 4.0 technologies and processing simulation solutions to [...] Read more.

Manufacturing processes can be cited as significant research areas when examining infrastructure systems and infrastructure, as they are inextricably linked to both. Examples include automobile manufacturing, the production of traffic signs, etc. Connecting and utilizing Industry 4.0 technologies and processing simulation solutions to address industry challenges, such as process optimization and fault detection, are gaining in popularity. Cyber-physical systems and digital twins connect the physical and cyber worlds to enable intelligent manufacturing capabilities, increased system flexibility, decreased manufacturing-cycle times, and improved quality. This paper presents a solution that improves the synchronization between the real (physical) and simulation (digital) layers, using discrete-event-driven simulations to create more efficient and accurate digital-twin environments. Using a combination of inexpensive commercial microcontrollers and an inertial-measurement-unit sensor to enhance a standard programmable logic controller process, a discrete-event-simulation-based digital layer is updated in real time to produce a live digital twin. The system can accurately identify and track products throughout the production cycle while simultaneously updating the digital twin in real time. Even independently, the algorithm running on the microcontroller can be used to gather the input parameters required for the simulation of production processes. The implemented environment can serve as a suitable testing ground for investigating the practical applicability of digital-twin solutions. Full article

(This article belongs to the Special Issue Land Transport, Vehicle and Railway Engineering)

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17 pages, 13717 KiB

Open AccessArticle

Probability of Risk Factors Affecting Small-Scale LNG Supply Chain Activities in the Indonesian Archipelago

by Rossy Armyn Machfudiyanto, Windra Priatna Humang, Nurul Wahjuningsih, Insannul Kamil and Yanuar Yudha Adi Putra

Infrastructures 2023, 8(4), 74; https://doi.org/10.3390/infrastructures8040074 - 06 Apr 2023

Cited by 1 | Viewed by 2139

Abstract

In Indonesia, the CoS for power supply increased from Rp. 1025 to Rp. 1334/KWh from 2016 to 2021, respectively; this indicates an inefficient process in electricity provision. One contributing factor to this inefficiency is the existence of many high speed diesel (HSD)-fueled power [...] Read more.

In Indonesia, the CoS for power supply increased from Rp. 1025 to Rp. 1334/KWh from 2016 to 2021, respectively; this indicates an inefficient process in electricity provision. One contributing factor to this inefficiency is the existence of many high speed diesel (HSD)-fueled power plants. These are distributed across the Indonesian archipelago with a supply chain that only uses sea transportation. The absence of an economical small-scale LNG (SS-LNG) supply chain also demonstrates the inadequate infrastructure for distributing LNG to refineries. This study aims to analyze the probability of risks that occur in SS-LNG supply chains in the Indonesian archipelago. The analytical methods used are descriptive statistical analysis and Delphi analysis through in-depth interviews and Focus Group Discussions (FGD) with experts. Results showed that the SS-LNG supply chain process in Indonesia includes LNG loading, unloading, shipping, picking, storage, regasification, and distribution. There are 30 risk indicators that may occur, with the highest risks including ship accidents, equipment damage, lack of transport ships, bad weather, earthquakes, tsunami, poor safety cultures, and low levels of safety leadership. These risk indicators can be used in implementing SS-LNG. Full article

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12 pages, 52314 KiB

Open AccessCommunication

Structural Design and Safety Verification of a Service Hatch Used at Airports by FEM Analysis

by Jakub Fiačan, Jozef Jenis, Damián Čechmánek, Slavomír Hrček and Pavol Michal

Infrastructures 2023, 8(4), 73; https://doi.org/10.3390/infrastructures8040073 - 06 Apr 2023

Cited by 2 | Viewed by 1760

Abstract

This paper examines the design of a maintenance shaft hatch cover at an airport service road which will be utilized at airports in the European Union. The shaft has a particular application: it will be used for information networks and airport security. The [...] Read more.

This paper examines the design of a maintenance shaft hatch cover at an airport service road which will be utilized at airports in the European Union. The shaft has a particular application: it will be used for information networks and airport security. The hatch is also subject to extremely stringent safety criteria. For instance, in a catastrophic case, a wheel from an aircraft could strike the hatch cover. Based on all the input information and after a thorough analysis of the European standards concerning the safety of transport, after performing numerous FEM static evaluations, a hatch cover that can be utilized in airport infrastructure was created. As a result of the FEM analyses, the elements with the greatest impact on static safety were identified. Finally, a simulation of stress tests based on the traffic areas for which the hatch cover was designed, in terms of traffic safety, was carried out. The test led to a positive result, showing that it is possible to apply the hatch directly in practice. Full article

(This article belongs to the Special Issue Land Transport, Vehicle and Railway Engineering)

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32 pages, 10684 KiB

Open AccessArticle

Investigations of Ratio-Based Integrated Influence Lines as Features for Bridge-Damage Detection

by Andreas Döring, Markus Vogelbacher, Oliver Schneider, Jacob Müller, Stefan Hinz and Jörg Matthes

Infrastructures 2023, 8(4), 72; https://doi.org/10.3390/infrastructures8040072 - 04 Apr 2023

Viewed by 1255

Abstract

Prestressed concrete bridges built between 1960 and 1990 no longer meet today’s requirements due to loads and increasing mileage of higher loads that have increased since the bridges were designed. Prestressed concrete bridges are representative of Germany’s existing bridges. In order to deal [...] Read more.

Prestressed concrete bridges built between 1960 and 1990 no longer meet today’s requirements due to loads and increasing mileage of higher loads that have increased since the bridges were designed. Prestressed concrete bridges are representative of Germany’s existing bridges. In order to deal with the large number of ageing bridges, recalculations and measurements for control as well as bridge monitoring are an important means of support. For both, it is important to find features that are damage-sensitive as well as robust against measurement noise, vehicle parameters (dynamics, geometry, weight, etc.) and environmental influences (temperature, wind, etc.). In this paper, we present features for damage detection based on the influence line, which are investigated with respect to the above requirements by using the analytical solution of the Euler–Bernoulli beam and more complex numerical bridge simulations. In this context, we restrict ourselves to the damage caused by bending stress. The features are calculated on the basis of single vehicle crossings over the bridge for the strain in the longitudinal direction as well as for the deflection of the bridge at different sensor positions. The ratio-based features are compared with raw data and natural frequencies in a classification. Additionally, the sensor positioning is considered. The investigations shows that the ratio-based integrated influence lines are equivalent to or better than the modal parameters, especially when noise and temperature changes are taken into account. Full article

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20 pages, 11811 KiB

Open AccessArticle

Prediction of Strain in Embedded Rebars for RC Member, Application of Hybrid Learning Approach

by Ali Mirzazade, Cosmin Popescu and Björn Täljsten

Infrastructures 2023, 8(4), 71; https://doi.org/10.3390/infrastructures8040071 - 04 Apr 2023

Viewed by 1269

Abstract

The aim of this study was to find strains in embedded reinforcement by monitoring surface deformations. Compared with analytical methods, application of the machine learning regression technique imparts a noteworthy reduction in modeling complexity caused by the tension stiffening effect. The present research [...] Read more.

The aim of this study was to find strains in embedded reinforcement by monitoring surface deformations. Compared with analytical methods, application of the machine learning regression technique imparts a noteworthy reduction in modeling complexity caused by the tension stiffening effect. The present research aimed to achieve a hybrid learning approach for non-contact prediction of embedded strains based on surface deformations monitored by digital image correlation (DIC). However, due to the small training dataset collected by the installed strain gauges, the input dataset was enriched by a semi-empirical equation proposed in a previous study. Therefore, the present study discussed (i) instrumentation by strain gauge and DIC as well as data acquisition and post-processing of the data, accounting for strain gradients on the concrete surface and embedded reinforcement; (ii) input dataset generation for training machine learning regression models approaching hybrid learning; (iii) data regression to predict strains in embedded reinforcement based on monitored surface deformations; and (iv) the results, validation, and post-processing responses to make the method more robust. Finally, the developed model was evaluated through numerous statistical performance measures. The results showed that the proposed method can reasonably predict strain in embedded reinforcement, providing an innovative type of sensing application with highly improved performance. Full article

(This article belongs to the Special Issue Application of AI for Non-invasive Assessment Methods to Monitor Surface Transportation Infrastructure)

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23 pages, 5627 KiB

Open AccessArticle

Multilevel Approach for Management of Existing Bridges: Critical Analysis and Application of the Italian Guidelines with the New Operating Instructions

by Agnese Natali, Antonella Cosentino, Francesco Morelli and Walter Salvatore

Infrastructures 2023, 8(4), 70; https://doi.org/10.3390/infrastructures8040070 - 31 Mar 2023

Cited by 3 | Viewed by 2000

Abstract

This paper provides a discussion and thoughtful application on a large sample of the procedures for the classification of existing bridges recently adopted in Italy and defined within the Italian Guidelines for the classification, risk management, safety evaluation and monitoring of existing bridges [...] Read more.

This paper provides a discussion and thoughtful application on a large sample of the procedures for the classification of existing bridges recently adopted in Italy and defined within the Italian Guidelines for the classification, risk management, safety evaluation and monitoring of existing bridges and the early published Operating Instructions. Focusing on the classification at the territorial level, first the logic flows to the classification on the base of the structural risk are shown, resulting in the definition of the “structural warning class”, providing the motivations that support the criteria for the definition of such procedures. Then, a statistical analysis of the results obtained from the classification of 661 existing Italian bridges is performed, focusing on the vulnerability classification and on the influence of each parameter on its evaluation. Full article

(This article belongs to the Section Infrastructures and Structural Engineering)

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28 pages, 9890 KiB

Open AccessArticle

Investigation of the Track Gauge in Curved Sections, Considering Hungarian Railway Lines

by Szabolcs Fischer, Dalma Németh and Henriett Horváth

Infrastructures 2023, 8(4), 69; https://doi.org/10.3390/infrastructures8040069 - 30 Mar 2023

Cited by 3 | Viewed by 1811

Abstract

In this paper, the authors examined the change in track gauges in curves for several railway lines with low and high traffic in Hungary (i.e., secondary lines and main lines). They covered the processing of raw data as well as statistical calculations. The [...] Read more.

In this paper, the authors examined the change in track gauges in curves for several railway lines with low and high traffic in Hungary (i.e., secondary lines and main lines). They covered the processing of raw data as well as statistical calculations. The considered curved sections were transition curves (TCs) and circular curves (CCs), as well as—in some cases—entire curves (ECs), including TCs and CCs, but not dividing them into parts. The change of track gauge parameter as a function of elapsed time was analyzed based on the distribution functions by calculating the Vaszary-type shape number. A statistical test with the Kolmogorov–Smirnov test was performed, in which the question as to whether the measurement data of the railway lines followed a normal or lognormal distribution was examined; additionally, the skewness and kurtosis parameters were calculated and analyzed. The authors also took into account the impact of the track system and the sleepers. For the selected curves, the authors observed how the average track gauge changes and categorized them according to tolerances. In presenting and summarizing the tests, the authors formulated a conclusion for each study fulfilled. Despite higher traffic loads, the value of track degradation over time is lower for mainline curves than for secondary line curves. It is because the main line has stricter tolerances due to the higher speeds allowed, and more maintenance work is carried out on these lines. The authors concluded that the type of the track system and the sleeper type also influence the change in track gauges in curves. The accurate deterioration ratios for all analyses are contained in the paper. Full article

(This article belongs to the Special Issue Land Transport, Vehicle and Railway Engineering)

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22 pages, 4320 KiB

Open AccessArticle

Environmental Impact Analysis of Alkali-Activated Concrete with Fiber Reinforcement

by Pujitha Ganapathi Chottemada, Arkamitra Kar and Patricia Kara De Maeijer

Infrastructures 2023, 8(4), 68; https://doi.org/10.3390/infrastructures8040068 - 30 Mar 2023

Cited by 2 | Viewed by 2957

Abstract

The scientific community is shifting its focus towards construction materials with a low carbon footprint, such as alkali-activated concrete (AAC). The present study conducts an environmental impact assessment using the cradle-to-grave approach to examine the environmental implications of three different types of ambient-cured [...] Read more.

The scientific community is shifting its focus towards construction materials with a low carbon footprint, such as alkali-activated concrete (AAC). The present study conducts an environmental impact assessment using the cradle-to-grave approach to examine the environmental implications of three different types of ambient-cured AACs with varied combinations of precursors. The 28-day compressive strength values of the concrete mixes used for comparing environmental impacts vary from 35 to 55 MPa. Among these mixtures, the one with the least environmental impact is chosen for further impact assessment with the inclusion of fibers. Three different fiber reinforced AAC mixes containing 0.3% steel, glass, and polypropylene fibers, respectively by volume of AAC, are used in this study. The findings show that Portland Cement concrete has 86% and 34% higher impacts than AAC on the ecosystem and human health, respectively. In the production of AAC, sodium silicate is found to have the highest impact on the environment, in the range of 30–50% of the total impact. Among the various fibers used, glass fibers have the highest impact, which is 12% and 13% higher than that of the plain AAC mix, on the ecosystem and human health, respectively. Full article

(This article belongs to the Special Issue IOCI 2022 Special Issue Session 4: Materials and Sustainability)

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24 pages, 6297 KiB

Open AccessArticle

A Risk Assessment Technique for Energy-Efficient Drones to Support Pilots and Ensure Safe Flying

by Szabolcs Kocsis Szürke, Norbert Perness, Péter Földesi, Dmytro Kurhan, Mykola Sysyn and Szabolcs Fischer

Infrastructures 2023, 8(4), 67; https://doi.org/10.3390/infrastructures8040067 - 28 Mar 2023

Cited by 2 | Viewed by 2002

Abstract

Unmanned Aerial Vehicles, also known as UAVs, play an increasingly important part in daily life. However, the ever-increasing number of UAVs pose an ever-increasing threat to the transportation infrastructure. Despite their precision and general efficiency, infrastructural-scale Unmanned Aerial Systems (UASs) have a disadvantage [...] Read more.

Unmanned Aerial Vehicles, also known as UAVs, play an increasingly important part in daily life. However, the ever-increasing number of UAVs pose an ever-increasing threat to the transportation infrastructure. Despite their precision and general efficiency, infrastructural-scale Unmanned Aerial Systems (UASs) have a disadvantage regarding their capability of being implanted in the ecosystem. There are several reasons for this, but the primary bottleneck is that their systems are not transparent to society and have very complicated processes. As a result, the authors decided to investigate the functional properties of UASs and make improvements to those properties. Throughout the study, the authors’ primary focus was on analysis, which boosts productivity and ensures a significant level of safety for routine flights. The amount of power that a UAV uses depends on several variables, including the amount of power that its individual components require, the temperature of its surroundings, and the condition of the battery that it is powered by. Therefore, critical parameters and interdependencies are taken into account in the risk assessment strategy for energy-efficient Unmanned Aerial Vehicles (UAVs). In the case of UAVs, the algorithm performs a risk calculation before take-off to estimate the amount of risk that can be associated with the given flight time when using the provided battery. On the one hand, several instances of the pre-take-off state and how its parameters interact are investigated. On the other hand, they demonstrate the calculation of the risk while in flight, which is based on actual flight data. Full article

(This article belongs to the Special Issue Land Transport, Vehicle and Railway Engineering)

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20 pages, 22254 KiB

Open AccessArticle

Image-Based Corrosion Detection in Ancillary Structures

by Amrita Das, Eberechi Ichi and Sattar Dorafshan

Infrastructures 2023, 8(4), 66; https://doi.org/10.3390/infrastructures8040066 - 28 Mar 2023

Cited by 2 | Viewed by 2449

Abstract

Ancillary structures are essential for highways’ safe operationality but are mainly prone to environmental corrosion. The traditional way of inspecting ancillary structures is manned inspection, which is laborious, time-consuming, and unsafe for inspectors. In this paper, a novel image processing technique was developed [...] Read more.

Ancillary structures are essential for highways’ safe operationality but are mainly prone to environmental corrosion. The traditional way of inspecting ancillary structures is manned inspection, which is laborious, time-consuming, and unsafe for inspectors. In this paper, a novel image processing technique was developed for autonomous corrosion detection of in-service ancillary structures. The authors successfully leveraged corrosion features in the YCbCr color space as an alternative to the conventional red–green–blue (RGB) color space. The proposed method included a preprocessing operation including contrast adjustment, histogram equalization, adaptive histogram equalization, and optimum value determination of brightness. The effect of preprocessing was evaluated against a semantically segmented ground truth as a set of pixel-level annotated images. The false detection rate was higher in Otsu than in the global threshold method; therefore, the preprocessed images were converted to binary using the global threshold value. Finally, an average accuracy and true positive rate of 90% and 70%, respectively, were achieved for corrosion prediction in the YCbCr color space. Full article

(This article belongs to the Special Issue Application of AI for Non-invasive Assessment Methods to Monitor Surface Transportation Infrastructure)

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13 pages, 1944 KiB

Open AccessArticle

Influence of Traffic Characteristics on Pavement Performance of Parking Lots

by Maen Qaseem Ghadi, Hesham Ahmad and Ismael Jannoud

Infrastructures 2023, 8(4), 65; https://doi.org/10.3390/infrastructures8040065 - 27 Mar 2023

Cited by 1 | Viewed by 2068

Abstract

This research aims to identify and interpret the main traffic characteristics affecting the pavement condition index (PCI) of asphalt within parking areas. The study also examines the effect of severity and type of asphalt pavement distress on parking decisions. Previous literature examines the [...] Read more.

This research aims to identify and interpret the main traffic characteristics affecting the pavement condition index (PCI) of asphalt within parking areas. The study also examines the effect of severity and type of asphalt pavement distress on parking decisions. Previous literature examines the impact of the environment on asphalt pavement deterioration. This paper will focus on the shape of traffic operations within a parking area. The methodology includes applying a multilevel mixed regression model to reveal the hidden hierarchical relationship between traffic activities and the different types of pavement distresses and then discovering their effect on asphalt PCI. The resulting models showed that parking lots are aging faster than the common traveling roads due to the increased impact of axial loads on their surfaces at low and static speeds and some distinctive traffic characteristics. Moreover, some types of pavement distress, such as alligator cracks, potholes and depressions, appear more widely than others on the parking lot surface and significantly influence the parking decision. The conclusion of the research may significantly impact pavement design and maintenance management for parking lots. Full article

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33 pages, 45713 KiB

Open AccessArticle

Calibration of Micromechanical Parameters for the Discrete Element Simulation of a Masonry Arch using Artificial Intelligence

by Ghulam Kibriya, Ákos Orosz, János Botzheim and Katalin Bagi

Infrastructures 2023, 8(4), 64; https://doi.org/10.3390/infrastructures8040064 - 24 Mar 2023

Cited by 4 | Viewed by 1788

Abstract

This study focuses on an old but still unresolved problem of automatically calibrating the constitutive parameters of discrete element models. Instead of the troublesome and time-consuming manual trial-and-error method, which is typical today, the authors suggest using artificial intelligence techniques. A masonry arch [...] Read more.

This study focuses on an old but still unresolved problem of automatically calibrating the constitutive parameters of discrete element models. Instead of the troublesome and time-consuming manual trial-and-error method, which is typical today, the authors suggest using artificial intelligence techniques. A masonry arch is analysed, whose experimental static load–displacement behaviour is known from the literature. An attempt is made to match this behaviour with discrete element models, through finding appropriate quantitative values for the parameters. Two methods (Genetic Algorithm (GA) and Particle Swarm Optimisation (PSO)) are tested and, since PSO turns out to be more reliable, a further improved version, ‘Trust-Based Particle Swarm Optimisation’ (TBPSO), is proposed. The results show that (1) TBPSO quickly leads to suitable alternative parameter sets that make the discrete element model match the behaviour of the real experiments and (2) the optimal values of the parameters strongly depend on the loading velocity and the discretisation method used. Full article

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

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11 pages, 3644 KiB

Open AccessArticle

Validation of Solid-State LiDAR Measurement System for Ballast Geometry Monitoring in Rail Tracks

by Enrique Aldao, Higinio González-Jorge, Luis Miguel González-deSantos, Gabriel Fontenla-Carrera and Joaquin Martínez-Sánchez

Infrastructures 2023, 8(4), 63; https://doi.org/10.3390/infrastructures8040063 - 23 Mar 2023

Cited by 2 | Viewed by 2071

Abstract

The inspection and maintenance of track ballast are fundamental tasks for the preservation of the condition of railway networks. This work presents an application based on a low-cost solid-state LiDAR system, which allows the user to accurately measure the ballast geometry from a [...] Read more.

The inspection and maintenance of track ballast are fundamental tasks for the preservation of the condition of railway networks. This work presents an application based on a low-cost solid-state LiDAR system, which allows the user to accurately measure the ballast geometry from a mobile inspection trolley or draisine. The solid-state LiDAR system, the LiVOX Avia, was validated on a test track through comparison with a traditional static LiDAR system, the Faro Focus 3D. The results show a standard deviation of around 6 mm for the solid-state LiDAR system. The LiVOX system also provides the capability to measure the ballast digital elevation model and profiles. The LiVOX results are in agreement with those obtained from the Faro Focus. The results demonstrate that the LiVOX system can sufficiently measure even the displacement of a single layer of ballast stones typically between 2.5 cm and 5 cm. The data provided can be easily digitalized using image processing tools and integrated into geographic information systems for infrastructure management. Full article

(This article belongs to the Topic Development of Monitoring, Analysis and Maintenance Technics of Infrastructures)

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