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A box culvert, buried at shallow depths beneath roadways, may experience deflections caused by the dynamic impact of traffic loading and the vertical pressure exerted by the soil fill. A computational model commonly employed used to various engineering issues, including those in geotechnical applications, is the beam-on- elastic-foundation model. In this context, the Moment Distribution Method (MDM) must be applied to account for the elastic foundation. To achieve this, the internal forces acting on the ends of both exterior and interior walls are transferred to the beam-like bottom slab of the culvert, which rests on an elastic soil bed. Subsequently, the secondary internal forces are determined by refining the structural parameters, taking into account the characteristics of the elastic soil bed. This study presents the development and application of an Artificial Neural Network (ANN) model to predict the shear capacity of box culverts on elastic soil under traffic loading conditions. The proposed model is trained and validated using a comprehensive database of beam on elastic foundation solutions. The input parameters include the geometrical and mechanical properties of the culvert and the soil, as well as the loading conditions. The results of the ANN model show R2 values of 0.9633 and 0.9581 for the training and testing sets, respectively, indicating the model's excellent accuracy. These findings suggest that the ANN model can reliably predict the shear capacity of culverts. [ABSTRACT FROM AUTHOR]

In view of the high-sensitivity vibration effect of precision instrument laboratory buildings under the influence of surrounding traffic loads, field micro-vibration tests under various working conditions were carried out based on actual projects. Combined with numerical simulation, measured data served as input loads to simulate the vibration effect of various traffic loads on the floor of a building structure, and the structural vibration laws under the comprehensive action of various loads were analyzed. The vibration isolation effect of the isolation ditch on the oblique orthogonal load was investigated according to the corresponding safety index. The results show that the main frequency components of the site vibration frequency caused by various traffic loads are approximately 25 Hz and that the root-mean-square speed value is stable below VC-E, which meets the design requirements. Under the comprehensive action of multiple loads, the site structure will produce a vibration amplification effect, which is obvious when all types of loads are distributed symmetrically and the curve distribution is controlled by load factors with large amplitudes. The isolation effect of a small isolation ditch is best when it is located close to the source and the building. The depth of the isolation ditch must be greater than the maximum depth of the source to achieve better results, and the width has little influence. The effect of a small isolation trench on vertical vibration is poor, and the oblique orthogonal triaxial load has a counteracting effect on the vertical component. Thus, additional structural vibration isolation measures are needed. The research results provide a reference for engineering vibration isolation, damping measures, and structural design. [ABSTRACT FROM AUTHOR]

This study aims to explore the dynamic response of loess slopes under traffic loads. By using finite difference software, a comprehensive numerical model of a typical loess slope was established. The analysis focused on understanding variations in slope deformation, vertical maximum acceleration, velocity, and displacement on the surface and inside of the slope under different axle loads and vehicle speeds. The results show that after applying traffic load, the shear strain increment zone of the slope extends from the toe to the crest. This extension indicates a potential development of the slip surface, and the instability of the slope begins with shear failure at the toe. As the distance from the load source increases, the vertical maximum acceleration, velocity, and displacement at each monitoring point on the surface and inside of the slope gradually decrease. Under the same speed and different axle load conditions, as the axle load increases, the vertical maximum velocity, acceleration, and displacement at each monitoring point on the surface and inside of the slope all show an increasing trend. Under fixed axle load and different speed conditions, the vertical maximum acceleration and velocity at each monitoring point inside and on the surface of the slope generally increase with the increase of vehicle speed, while the displacement gradually decreases with the increase of driving speed. The research findings have important theoretical significance and practical engineering application value for understanding the dynamic response of loess slopes to traffic load and road construction within loess regions. [ABSTRACT FROM AUTHOR]

When traffic flows pass through existing bridges, the dynamic effect of the vehicle loads increases due to the local surface damage rather than the entire roughness level of the bridge deck. This study presents a method for evaluating a dynamic impact factor (IM) from a bridge dynamic response under a traffic flow considering the local surface damage. The random axle loads of traffic vehicles under the deteriorated roughness conditions are presented using an input load time-history applied to each discretized deck node of a finite element bridge model. The amplification ratios of the root mean square of the simulated acceleration under nominal road surface conditions with respect to the specified IMs in the design stage are calculated. The relationship between the ratios and IMs is determined to evaluate the dynamic impact factors under any surface roughness condition. The method is validated by applying it to two existing bridges with different road surface damage and traffic conditions. The results show that the IMs depend on both the traffic loading and bridge surface roughness conditions. Under the same traffic flow conditions, the values increase when the road surface damage increases. However, the increases in the IMs vary according to the location of the surface roughness deterioration in both of the target bridges. [ABSTRACT FROM AUTHOR]

The cumulative deformation and fatigue failure of roadbeds induced by dynamic loads are fundamental considerations in road traffic design. To gain a more comprehensive understanding of the impact of drainage conditions and loading cycles on the performance of roadbeds composed of granite residual soil in southern China under various loading modes, this study conducted high-cycle dynamic triaxial tests using a DDS-70 dynamic triaxial apparatus. Through analysis of sample deformations, pore pressure development, and changes in critical cyclic stress ratio under different simulated waveforms, it was observed that the simulated waveform significantly influences the dynamic characteristics of the soil, with the half-sine wave proving effective in simulating the complex dynamic stress caused by traffic vehicles. Meanwhile, the study revealed uncertainties in the development of cumulative deformation under undrained conditions, thus indicating a need for dynamic tests to be conducted under drained conditions to more accurately replicate the effects of traffic loads. Additionally, the deformation of samples at 1000 cycles can serve as a crucial reference for estimating final deformation, which is essential for determining sample types and obtaining key parameters of foundation soil. This approach can help reduce testing workload and save time and costs. [ABSTRACT FROM AUTHOR]

The article presents the results of an analysis of snow cover pollution in different parts of the Kirovsky district of Saratov. A comparison of the obtained data with the 1992 indicators was carried out. The connection between transport hubs with the highest dust load values and an increase in the number of cars was determined. Current spatial and temporal trends in snow cover pollution have been identified. The fact was confirmed that the highest concentration of dust in the snow cover is detected in areas with high traffic load. Determining the relationship between the increase in dust load in the study areas and the increase in the number of cars over a period of 30 years confirms the significant impact of transport on the ecological state of the environment in urbanized areas.

Bridges are a critical element of the transport network. In case of neglected maintenance, war conflict or natural disaster, they may be damaged or destroyed. An alternative solution in the form of a detour is mostly feasible only in the case of ground communication. But even in this case, it can be a very difficult and lengthy solution. Therefore, temporary bridges are often used to replace the permanent bridge structure for a certain time. The history of temporary bridges is essentially as old as that of permanent bridges. The first patented temporary bridge was the Eifel Bridge, which had a span of up to 60.0 m in 1888. Before the Second World War, the most widespread structures were the German S-bridge with spans of up to 15.0 m, Herbert-brücke with a span of up to 25.0 m and the English Bailey bridge system. In the post-war era, the ŽM 60 temporary bridge was designed as a universal bridge structure, which was to serve to temporarily bridge obstacles of medium and long spans. As standard, it was to serve as a railway bridge with a span of up to 60.0 m and as a road bridge with a span of 84.0 m. The task of the study published in this paper is to approach the possibilities of deploying the ŽM 60 bridge at present in compliance with the requirements arising from currently applicable standards and regulations.

The seamless integration of intelligent Internet of Things devices with conventional wireless sensor networks has revolutionized data communication for different applications, such as remote health monitoring, industrial monitoring, transportation, and smart agriculture. Efficient and reliable data routing is one of the major challenges in the Internet of Things network due to the heterogeneity of nodes. This paper presents a traffic-aware, cluster-based, and energy-efficient routing protocol that employs traffic-aware and cluster-based techniques to improve the data delivery in such networks. The proposed protocol divides the network into clusters where optimal cluster heads are selected among super and normal nodes based on their residual energies. The protocol considers multi-criteria attributes, i.e. energy, traffic load, and distance parameters to select the next hop for data delivery towards the base station. The performance of the proposed protocol is evaluated through the network simulator NS3.40. For different traffic rates, number of nodes, and different packet sizes, the proposed protocol outperformed LoRaWAN in terms of end-to-end packet delivery ratio, energy consumption, end-to-end delay, and network lifetime. For 100 nodes, the proposed protocol achieved a 13% improvement in packet delivery ratio, 10 ms improvement in delay, and 10 mJ improvement in average energy consumption over LoRaWAN. [ABSTRACT FROM AUTHOR]

In the evaluation of existing bridges and viaducts, relying solely on a desk study is often inadequate for determining their structural reliability. Performing a proof load test provides valuable field data that offers detailed information about the structural integrity. However, the relation between the magnitude of the load and the structural reliability is not immediately clear. This study addresses the challenges associated with determining the target load and highlights the uncertainties that play a key role. A case study is presented that shows the time-dependent character of the structural reliability and the influence of an informative and a weakly informative prior distribution in a Bayesian context. It is shown how both past traffic loads and a proof load test may contribute to the proven strength of a structure. The described method provides a starting point towards a flexible approach for proof load testing in which structure-specific knowledge levels and requirements are considered. [ABSTRACT FROM AUTHOR]

Using coal gangue as a subgrade filler will produce good benefits, and its application prospects are very broad. It is of great engineering and scientific value to study the improvement method and dynamic characteristics of coal gangue subgrade filler under traffic load. Combining the properties of coal gangue material, fly ash and lime and soil were added to improve the bearing behavior of coal gangue subgrade filler. Then, a compaction test was carried out using the principle of orthogonal experimental design. By analyzing the compaction test results, the optimal proportion of each additive was obtained. A large-scale dynamic triaxial test was carried out with the proportion of each admixture in the maximum dry density group in the compaction test. Based on the dynamic triaxial test results, the effect of confining pressure on the permanent strain was analyzed, the analysis model of permanent deformation and cycle number of traffic loading was proposed, and the correctness of the model was verified. In addition, a modified Hardin–Drnevich model was established, which can describe the dynamic stress–dynamic strain curve of coal gangue subgrade filler under traffic load, and then, the dynamic modulus and damping ratio were analyzed. [ABSTRACT FROM AUTHOR]

Various numerical methods are commonly used to model the loading response of traffic infrastructures. However, the broader implementation of these methods into practice is typically limited by the high computing cost or technical complexity of the models. Computationally lighter methods are especially needed when a substantial number of calculations must be performed. Hence, this paper introduces a new simplified approach to estimating the loading response of different traffic infrastructures, e.g. roads and railways. This approach is based on the novel approximate solution for the vertical and shear stress fields caused by a uniformly distributed circular surface load. The presented theory has been validated using versatile field measurement data from different types of road structures under varied loading conditions. In the verification calculations, both the vertical stresses within the structure and the deflection of the road surface were examined. The findings indicate that the model closely aligns with the behavior observed in actual structures. The approach presented in this paper enables a quick and easy determination of the loading response of multi-layer traffic infrastructures, providing a new practical calculation tool for researchers and practitioners.

The temperature state of warm permafrost is in the negative temperature near-phase-transition interval and thus is extremely sensitive to small fluctuations of the heat and stress environment. The dynamic load induced by the vehicle operation not only changes its magnitude cyclically, but also its principal stress direction (PSD) consistently changes rotationally. However, the existing conventional dynamic research methods can only simulate the cyclic stress environment with constant PSD, which is very different from the stress environment induced by locomotive operation, and thus the conventional dynamic research results are bound to be difficult to accurately reflect the influence of the stress field induced by vehicle operation on the development law of warm permafrost permanent settlement deformation. Therefore, in this paper, a series of dynamic studies were carried out for the Qinghai-Tibet silt at −2 °C by simulating the cardioid-shaped stress path induced during the operation of a heavy-duty locomotive using a frozen hollow cylinder apparatus. It is found that the rotational effect of the principal stress direction under the conditions of the cardioid-shaped stress path (CSSP) action accelerates the development of vertical permanent deformation in the frozen soil. The main reason that caused the axial strain increases advantage is the rotation of principal stress direction can accelerate the viscous energy dissipation during dynamic loading process. According to the law of axial strain development in the high-temperature frozen soil under the conditions of different CSSP action, an empirical model of permanent deformation development in high-temperature frozen soil considering the PSD rotation effect was established, and it was found by this model calculation that under the general condition of heavy-load locomotive operation, compared with the conventional research method without considering the PSD rotation, the axial cumulated strain in high-temperature frozen soil increased by 33.3% after considering the rotation effect in the PSD. [ABSTRACT FROM AUTHOR]

In view of the high-sensitivity vibration effect of precision instrument laboratory buildings under the influence of surrounding traffic loads, field micro-vibration tests under various working conditions were carried out based on actual projects. Combined with numerical simulation, measured data served as input loads to simulate the vibration effect of various traffic loads on the floor of a building structure, and the structural vibration laws under the comprehensive action of various loads were analyzed. The vibration isolation effect of the isolation ditch on the oblique orthogonal load was investigated according to the corresponding safety index. The results show that the main frequency components of the site vibration frequency caused by various traffic loads are approximately 25 Hz and that the root-mean-square speed value is stable below VC-E, which meets the design requirements. Under the comprehensive action of multiple loads, the site structure will produce a vibration amplification effect, which is obvious when all types of loads are distributed symmetrically and the curve distribution is controlled by load factors with large amplitudes. The isolation effect of a small isolation ditch is best when it is located close to the source and the building. The depth of the isolation ditch must be greater than the maximum depth of the source to achieve better results, and the width has little influence. The effect of a small isolation trench on vertical vibration is poor, and the oblique orthogonal triaxial load has a counteracting effect on the vertical component. Thus, additional structural vibration isolation measures are needed. The research results provide a reference for engineering vibration isolation, damping measures, and structural design.

The European railway network includes many steel truss girder bridges, often dating back to the end of the nineteenth century. Assessment by the partial factor method according to Eurocodes often reveals insufficient reliability of these bridges. In particular, they fail to satisfy the equilibrium limit state when a strong wind occurs simultaneously with an unloaded train crossing the bridge. To avoid unnecessary structural interventions and expensive traffic restrictions, representative types of these bridges are tested in a wind tunnel to refine the force coefficients of wind pressure for the specific shape of the bridge and selected types of lightweight train. The values of force coefficients based on wind tunnel tests correspond to 70–80% of those provided in EN 1991–1–4. Traffic flow records for the railway line under consideration are then utilised to obtain distributions of weights and heights of lightweight trains. Detailed probabilistic analysis focused on a long-span truss bridge with an intermediate bridge deck demonstrates that the reliability of this bridge is close to the target reliability level when wind tunnel force coefficients are considered along with site-specific free-field wind and railway traffic records. [ABSTRACT FROM AUTHOR]

Piezoelectric energy harvesting from traffic load has gained extensive attention for potentiality as a renewable energy source. In existing in situ experiments, generally only one vehicle is employed, while the wheel-path of the vehicle and embedded positions of piezoelectric energy harvester (PEH) units are both fixed. However, in an actual traffic condition, vehicles travel randomly along width of pavements, which means the wheel-path varies over time and among vehicles. In this study, an electromechanical model is established for the PEH units under actual traffic conditions with wheel-path distribution, and is validated with finite element analysis and experiments. Then the electrical performance of PEH units embedded at various locations along pavements' lateral direction is investigated under various traffic speeds. It is found that the optimal lateral embedded locations of the PEH units should be adjusted according to the prescribed traffic speed of the roads. Specifically, PEH units should be embedded at the tire-road contact areas for road with low traffic speeds (<15 m/s), while they should be embedded at the center of the pavement with high traffic speeds (>25 m/s). These mathematical results may serve as guidelines for selecting optimal lateral embedded locations for PEH units embedded in pavements. [ABSTRACT FROM AUTHOR]

According to modern structural codes, a design is considered to be adequate if the limit states are not exceeded. For the ultimate limit state, the design value of action effect Ed is required to be less or equal than the design value of ultimate resistance Rd. This ensures, according to the Eurocode, a sufficiently low probability of failure expressed as the target reliability index β. Consequently, the distributions of action effect and of resistance need to satisfy the following conditions: P E > E d ≤ Φ + α E β and P R ≤ R d ≤ Φ − α R β , where αE and αR, with |α| ≤ 1, are the values of the FORM sensitivity factors. The values of the sensitivity factors αE and αR are suggested, according to EN1990, as −0.7 and 0.8, respectively; for the accompanying actions, the sensitivity factor is recommended as 0.28. In this paper, the dependence of the sensitivity factors for traffic live load, dead load, and resistance on the ratio of traffic load to dead load is studied (which is directly proportional to the maximum span of the bridge). Significantly different sensitivity factors for resistance, dead load, and traffic load, other than proposed by the Eurocode, has been calculated for typical ratio of traffic to dead load. It further showed that, if it is assumed that Ed = Rd and the Eurocode partial safety factors are used, a different design point than the starting point, i.e., Ed = Rd, is obtained. [ABSTRACT FROM AUTHOR]

Differential settlement is the most intuitive embodiment of the safety of an embankment near the junction of above soft and hard subgrade. The prestressed geosynthetic-reinforced embankment (GRE) was implemented to avoid excessive settlement disasters. The settlement resistance of the prestressed GRE was explored by experimental and numerical investigation. The laboratory model test of the GRE with and without prestress under the traffic load was presented. The results are shown that there is larger stress diffusion range and faster stress attenuation along the depth direction of the GRE with prestress than that without prestress. In comparison with the GRE, the differential settlement of the prestressed GRE was smaller by about 38%–53% of the decreasing percentage range. Moreover, based on numerical test results and gray correlation analysis, the influence and susceptibility of the prestress value and the prestressed member spacing on the settlement control capability of the prestressed GRE were also investigated. It was found that reducing the member spacing has a positive impact on avoiding settlement disasters, and increasing prestress also can significantly control settlements. The spacing of prestressed members is more sensitive to the settlement resistance of prestressed GRE than the prestress value. It is of practical significance, considering the obvious settlement resistance, to apply the prestressed GRE to mountainous areas with potential excessive settlement hazards. [ABSTRACT FROM AUTHOR]

Purpose: The vibration isolation performance of a novel graded wave-impeding block (WIB) was studied under various train loads. Methods: Large-scale indoor model tests were conducted to simulate the train motion vibration, and the vibration isolation performance between a novel graded WIB and an ordinary homogeneous WIB was measured and compared. The novel graded WIB was primarily composed of three layers of media with different physical and mechanical properties, and a concrete canvas was used as an interlayer between each layer. Results: By simulating different train speeds and loads, the subgrade settlement, vertical vibration velocity, frequency, and displacement were compared and analysed under various working conditions. Moreover, the vibration response of the subgrade soil was analysed using the vibration control equation. Conclusions: The experimental results showed that the novel graded WIB had a better vibration isolation effect compared with the homogeneous WIB. [ABSTRACT FROM AUTHOR]

Accurate estimation of traffic load plays a crucial role in the economical design of pavements. The cross sectional distribution of the vehicle positions means that the traffic load is spread across the surface of the pavement. Several factors influence the distribution of vehicle positions and hence load. When wheel paths are perfectly aligned with each other, this is termed channelised traffic (or channelisation). This study investigated the impact of channelisation on asphalt pavement rutting. Data was collected on 100 sections of pavement in the city of Portsmouth, United Kingdom including vehicle/wheel positions and rut depths. Regression analysis was conducted to understand how the degree of channelisation influenced the rut depths that the traffic loading had created. The analyses revealed that the degree of channelisation of traffic has a statistically significant contribution to the progress of rutting. In this study, the difference between the maximum and minimum degrees of channelisation observed, related to a seven-fold difference in the rut depth. These findings give further guidance to pavement engineers when designing new pavements and considering the maintenance schedules for existing pavements, as it allows them to better predict the future condition and lifespan of a pavement. [ABSTRACT FROM AUTHOR]

Cavities under roads are one of the main reasons for early structural damage to pavements. It is necessary to conduct a structural analysis of road sections with cavities and evaluate the possibility of pavement cracking caused by different cavity sizes. In this study, an analysis method for evaluating the possibility of pavement cracking based on the load-mechanical response is proposed. An example library of the mechanical response of asphalt concrete (AC) pavements was established by numerical simulation. Based on the tensile cracking characteristics of pavements in the mechanical response research, the tensile strain at the bottom of the AC layer was selected as the key analysis parameter. Sensitivity analysis of the tensile strain was conducted, and the main factors controlling pavement cracking were determined. A tensile strain response prediction model was established using multiple linear regression, and its reliability was verified. The cavity influence coefficient (CIC) and pavement cracking factor (PCF) were constructed to analyze the cracking possibility. The variation in PCF with the cavity size and pavement structure parameters was studied. A quantitative relationship between the depth and length of the cavity for a given PCF was obtained. This law conforms to a power function. The possibility of pavement cracking can be determined by measuring the cavity size. Compared to the existing cavity management system, the proposed method provided analysis results of the cracking possibility that were more consistent when the cavity depth was small and the length was long. The findings of this study provide new insights for evaluating the possibility of pavement cracking. [ABSTRACT FROM AUTHOR]

Using coal gangue as a subgrade filler will produce good benefits, and its application prospects are very broad. It is of great engineering and scientific value to study the improvement method and dynamic characteristics of coal gangue subgrade filler under traffic load. Combining the properties of coal gangue material, fly ash and lime and soil were added to improve the bearing behavior of coal gangue subgrade filler. Then, a compaction test was carried out using the principle of orthogonal experimental design. By analyzing the compaction test results, the optimal proportion of each additive was obtained. A large-scale dynamic triaxial test was carried out with the proportion of each admixture in the maximum dry density group in the compaction test. Based on the dynamic triaxial test results, the effect of confining pressure on the permanent strain was analyzed, the analysis model of permanent deformation and cycle number of traffic loading was proposed, and the correctness of the model was verified. In addition, a modified Hardin–Drnevich model was established, which can describe the dynamic stress–dynamic strain curve of coal gangue subgrade filler under traffic load, and then, the dynamic modulus and damping ratio were analyzed.

Industrial production of chemical cement leads to extreme emissions of greenhouse gases. Biological or bio-inspired sustainable materials for soil treatment projects can be employed instead of chemical cement to heal the carbon cycle in the ecosystem. The enzyme-induced calcite precipitation (EICP) method is one of the novel bio-inspired technologies that can be employed in soil treatment projects to increase desired properties of soils. While the monotonic and cyclic behavior of the enzymatically treated sands has been investigated comprehensively, the strain accumulation pattern in these improved soils under cyclic traffic loads has not been evaluated yet. In this paper, confined and unconfined cyclic compression tests are applied to the enzymatically lightly cemented sands, and the effects of the different parameters on their strain accumulation pattern are investigated for the first time in the literature. This study uses two types of specimens with unconfined compression strengths (UCS) equal to 42 ​kPa and 266 ​kPa. It is shown that the treated specimens have a rate-dependent behavior where cyclic loads with low frequencies lead to more resilient and plastic strains in the specimens. The results show that by approaching the maximum applied stresses to the UCS of the specimens (by breaking more calcite bonds between sand particles), the rate dependency behavior of specimens will reduce. Investigation of the effects of the cementation level demonstrated that by increasing the amount of the precipitated calcite from 0.38% to 0.83%, accumulated plastic strains are reduced almost 95% under the same loading condition. Effects of the initial static loads, confining pressures, the number of cycles, and amplitudes of the cyclic loads are also evaluated.

Suspension bridge is a flexible structure. The weight, location and number of traffic on the bridge will affect the geometric alignment of the bridge. Although the finite element software can analyze the geometric nonlinearity of the bridge, the calculation of random load combination in finite element software is huge. In this paper, based on the deformation coordination, static equilibrium and constitutive model of the bridge, the force expression considering the geometric nonlinearity of the bridge is derived. Finite element software is used to simulate the internal force of components of suspension bridge under train load and vehicle load. The accuracy is verified by comparing the finite element results. Considering the random number of traffics, the random location of traffics, and the random weight of traffics, this paper analyzes the stress state of bridge under the random process of train load and vehicle load respectively. The method in this paper can be well used to analyze the actual stress state of the bridge, and provide a theoretical basis for related calculations. [ABSTRACT FROM AUTHOR]

Traffic loads have an important impact on long-term performance of buried urban pipelines due to generation of cyclic stress and fatigue damage. As a key task for pipeline fatigue assessment, the investigation of traffic-induced pipe stress and fatigue load spectrums is always a big challenge. Focusing on the metal pipelines buried under urban intersection, an integrated framework is proposed for fatigue assessment of the pipelines under traffic loads using video monitoring data acquired by the widespread surveillance cameras in cities. The computer vision algorithms and a quarter vehicle model are first employed to identify traffic loads. Analytical pipe-soil models are then developed to calculate pipeline stress and establish the traffic-induced fatigue load spectrums of buried pipelines, based on which the Monte-Carlo simulations are finally conducted to evaluate cumulative fatigue damage and fatigue reliability. A case study on a DN500 steel pipeline buried under an urban intersection demonstrates and validates the fatigue assessment procedure. The results can provide a basis for decision support regarding maintenance and replacement of urban pipelines. [ABSTRACT FROM AUTHOR]

Due to increasing precipitation intensity, rising sea level, and land development, urban flooding has become a major issue in many places around the world. This research aims to develop underground storage tanks (USTs) using fiber-reinforced polymer (FRP) materials for stormwater detention, storage, and reuse. The USTs are intended to be placed underneath highway or street pavements. FRP as one of the emerging structural materials possesses several advantages including high strength-to-weight ratio and corrosion resistance. The mechanical performance of USTs has rarely been visited in the literature, the majority of which focuses on leakage issues and associated environmental problems. This paper presents detailed analyses of the mechanical performance of FRP USTs, including a laboratory test on a small-scale FRP UST and a verified finite element (FE) analysis on full-scale FRP USTs. The influences of various factors on the mechanical performance of the USTs were examined, including wall thickness, water storage, interfacial roughness between FRP and soil, and tank sizes. Both results from experiments and FE studies agree satisfactorily and reveal that (i) underground FRP UST developed tensile axial strains at the top surface at the mid-span of the tank and the side surface at the mid-height; (ii) compressive axial strains developed in most of the cap region; and (iii) large compressive circumference strains developed in the FRP UST in most locations. Insights gained from the laboratory test and the FE analysis are expected to provide a general guidance on the design of FRP USTs under road pavements for urban flooding mitigation and stormwater harvesting. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

It is beneficial to the sustainable development of expressway engineering to reuse excavated soil as roadbed filling material. There are a large number of filling projects using loess as a filling material in Northwest China. In this paper, the loess subgrade of an expressway in Lanzhou is taken as the research object, and a series of experimental studies are conducted using a hollow cylindrical torsion shear system to simulate the formation of a "heart-shaped" stress path and the principal stress rotation (PSR) under long-term traffic loads. The effects of the vertical cyclic dynamic stress ratio, torsion shear stress ratio, initial static shear stress, and intermediate principal stress coefficient on the axial plastic deformation and rebound deformation of compacted loess in Lanzhou were studied. The results show that the vertical cyclic stress ratio (VCSR) has a significant effect on the axial deformation of compacted loess in Lanzhou. When the VCSR is less than 0.6, all the axial strain curves develop stably with the number of cycles. With an increasing VCSR, the axial plastic deformation increases obviously, and the axial rebound deformation also increases. The vertical cyclic dynamic stress of the specimen is constant. Moreover, increasing the torsional shear stress ratio (that is, increasing the amplitude of cyclic shear stress) can greatly increase the development of axial deformation, but it has no effect on the rebound deformation curve. When the initial static shear stress exists in the specimen, the larger the initial static stress ratio (SSR) is, the larger the axial plastic deformation. The axial plastic deformation increases by approximately 33% for every 0.1 increase in the SSR. The rebound deformation of different SSRs fluctuates at the initial stage of cyclic loading, but the final stable rebound deformation is basically the same as that at the initial stage of cyclic loading. The intermediate principal stress coefficient has no effect on the development of axial strain, and the effect on axial rebound deformation is negligible. Finally, the calculation model of the axial plastic strain of Lanzhou compacted loess under traffic loads is obtained. The research results can provide a reference for the durability and settlement prediction in loess engineering. [ABSTRACT FROM AUTHOR]

The generalized integration of new communication technologies is expected to improve the lives of humans and edge us closer to achieving the Sustainable Development Goals in the next ten years. People will benefit from the rapid exchange of information, high-speed data transfer, the high-quality protection of uploaded and transmitted information, greater accessibility to medicine, the development of smart cities and homes, etc. But there are factors that significantly hinder the spread of fifth-generation mobile networks, the most critical being the high energy consumption that comes with the rapidly growing number of devices, machines, and mobile subscribers. Most often, base stations always operate at full capacity, but there are statistics that show that the flow of base station clients is not always the same, so energy consumption may be managed. It was found that cell zooming algorithms that mostly consider client flow can save 14–80% of base station power consumption; however, not all studies pay attention to the quality of service. By balancing energy saving and the quality of service, base station energy savings of about 15% can be achieved. In modern research, dynamic network scaling algorithms are more often presented, and location management investigation has been identified as a solution that can help improve energy-saving techniques and keep the quality of service at the optimal level. [ABSTRACT FROM AUTHOR]

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Future smart cities are expected to provide intelligent services such as predictions, detections, and automation through digital twins. However, the creation of digital twins requires the processing of an enormous amount of data, thereby leading to an increase in mobile network traffic. This traffic is produced by applications in user devices and city services, which engage in local consumption at the city scale through sensor and camera devices using mobile networks. Such increased traffic can compromise the communication speed and stability. To alleviate this burden, traffic offloading becomes a crucial consideration in the beyond-5G era. This paper presents a scheme known as Area-Controlled Mobile Ad-Hoc Networking (AMoND). AMoND uses a hierarchical structure of a location layer and an ad-hoc layer to construct area-controlled mobile ad-hoc networks (MANETs) for mutual support of the digital twin and MANETs. AMoND effectively suppresses mobile network traffic by harnessing the digital twin to assist the MANETs during data collection for the digital twin construction. Importantly, the digital twin used in AMoND focuses on the management of node location information and does not need to reproduce the real space on a computer fully. AMoND is not dependent on a specific MANET protocol and can be used as an add-on. AMoND exhibits the ability to reduce traffic volumes by up to approximately 65%, while maintaining arrival rates that are comparable to existing MANET protocols under certain conditions.

Abstract Allocating resources is crucial in large-scale distributed computing, as networks of computers tackle difficult optimization problems. Within the scope of this discussion, the objective of resource allocation is to achieve maximum overall computing efficiency or throughput. Cloud computing is not the same as grid computing, which is a version of distributed computing in which physically separate clusters are networked and made accessible to the public. Because of the wide variety of application workloads, allocating multiple virtualized information and communication technology resources within a cloud computing paradigm can be a problematic challenge. This research focused on the implementation of an application of the LSTM algorithm which provided an intuitive dynamic resource allocation system that analyses the heuristics application resource utilization to ascertain the best extra resource to provide for that application. The software solution was simulated in near real-time, and the resources allocated by the trained LSTM model. There was a discussion on the benefits of integrating these with dynamic routing algorithms, designed specifically for cloud data centre traffic. Both Long-Short Term Memory and Monte Carlo Tree Search have been investigated, and their various efficiencies have been compared with one another. Consistent traffic patterns throughout the simulation were shown to improve MCTS performance. A situation like this is usually impossible to put into practice due to the rapidity with which traffic patterns can shift. On the other hand, it was verified that by employing LSTM, this problem could be solved, and an acceptable SLA was achieved. The proposed model is compared with other load balancing techniques for the optimization of resource allocation. Based on the result, the proposed model shows the accuracy rate is enhanced by approximately 10–15% as compared with other models. The result of the proposed model reduces the error percent rate of the traffic load average request blocking probability by approximately 9.5–10.2% as compared to other different models. This means that the proposed technique improves network usage by taking less amount of time due, to memory, and central processing unit due to a good predictive approach compared to other models. In future research, we implement cloud data centre employing various heuristics and machine learning approaches for load balancing of energy cloud using firefly algorithms.

This research aims to assess the effect of temperature gradient developed within the concrete slab of rigid pavement, and to investigate its impact when incorporated with the traffic load, and the heat transfer pattern. The rigid pavement model considers an isotropic, uniform, and linear-elastic schemes to simulate the material properties. A numerical analysis approach was employed using Abaqus software incorporated with the 3D Solid model. The traffic loads were obtained from the field surveys, while the temperature of the slabs was measured directly on the site. The dimension of the rigid panel is 2.75 m in width, 5 m long, slab thickness of 25 cm, and concrete specification of 41.33 MPa. The results showed that the temperature gradient produced a significant impact on stress development within the concrete slab of rigid pavement. It was observed that the temperature gradient during the daytime generated higher stress than at night, with a value reaching the MOR (Modulus of Rupture). The exposure of the rigid pavement to 500C tends to produce a principle slab stress of 2.395 MPa, while 1.31 MPa was developed due to the traffic load. When the two factors were combined, the concrete slab acquired a maximum principle stress of 3.322 MPa, which is close to the MOR of 83.34% fa. These results showed that the pavement is capable of withstanding stress from temperature gradient and traffic load as indicated by the ratio of less than one (1). However, this ratio is high for fatigue failure mitigation purposes, and this reduces the quality of life of the rigid pavement. [ABSTRACT FROM AUTHOR]

Recently, different techniques have been applied to detect, predict, and reduce traffic congestion to improve the quality of transportation system services. Deep learning (DL) is becoming increasingly valuable for solving critiques. DL applications in transportation have been collected in several recently published surveys over the last few years. The existing research has discussed the cloud environment, which does not provide timely traffic forecasts, which is the cause of frequent traffic accidents. Thus, a solid understanding of the difficulties in predicting congestion is required because the transportation system varies widely between non-congested and congested states. This research develops a bi-directional recurrent neural network (BRNN) using Gated Recurrent Units (GRUs) to extract and classify traffic into congested and non-congested. This research uses a bidirectional recurrent neural network to simulate and forecast traffic congestion in smart cities (BRNN). Urban regions worldwide struggle with traffic congestion, and conventional traffic control techniques have failed miserably. This research suggests a data-driven approach employing BRNN for traffic management in smart cities, which uses real-time data from sensors and linked devices to control traffic more efficiently. The primary measures include predicting traffic metrics such as speed, weather, current, and accident probability. Congestion prediction performance has also been improved by extracting more features such as traffic, road, and weather conditions. The proposed model achieved better measures than the existing state-of-the-art methods. This research also explores an overview and analysis of several early initiatives that have shown promising results; moreover, it explores two potential future research approaches to increase the accuracy and efficiency of large-scale motion prediction. [ABSTRACT FROM AUTHOR]

To reveal the mechanical characteristics of BRT asphalt pavement structures under the combined effects of the temperature field and load of buses, a series of finite element analysis models were established in the software application ABAQUS to simulate the Lanzhou BRT asphalt pavement project. The actual BRT road temperature field in summer and loads of buses at different speeds were introduced in the model with user subroutines before conducting a sequentially coupled thermal-mechanical analysis. The results indicated that the BRT asphalt pavement structure readily experienced permanent deformation, mainly comprising unstable rutting during the high-temperature season, and the possibility of cracking was higher for the subbase bottom than for the base. Temperature imposed a greater influence than BRT vehicle frequency. To delay fatigue cracking of the base and subbase and the shear failure of asphalt pavement structures, BRT operating speed should be controlled within 30–40 km/h. In actual BRT asphalt pavement engineering, special attention should be given to the deformation resistance of the intermediate surface layer. [ABSTRACT FROM AUTHOR]

The long-span suspension bridge has suffered from multiple failures of restraints such as supports, dampers, and expansion joints due to excessive accumulated displacement at the girder end. To investigate the main girders’ characteristics in the longitudinal motion of these bridges and the influence of the restraint device on the longitudinal displacement, the motion characteristics were first analyzed based on the measured displacement data of a certain bridge’s main girder; a dynamic finite element model of the bridge’s random traffic flow was then established based on the measured WIM data; combined with the girder end displacement monitoring data, the Euclidean distance was used to verify the correctness and rationality of the proposed model; finally, the model is used to discuss the influence of restraint devices (i.e., viscous dampers and supports) on the main girder in the longitudinal direction. The results show that dynamic loads (such as vehicles and wind) are the principal reasons for huge accumulated travel at the girder end; The viscous damper can effectively control the longitudinal movement; in a certain range, the larger the damping index, the better the control effect of the damper; meanwhile, the friction coefficient of the support also affects the longitudinal motion, but the effect is limited. When the friction coefficient is ≤ 0.03, the girder end’s cumulative displacement gradually decreases with the increasing friction coefficient, and compared to the damping index, the friction coefficient plays a major controlling role in the girder end displacement; when the friction coefficient is >0.03, the damping index plays a major controlling role in the girder end displacement.

Urban flooding has become one of the major issues in many cities around the world, due to rising sea level, increasing precipitation intensity, and land development. This research aims at the development of underground storage tanks (USTs) using fiber-reinforced plastic (FRP) materials for stormwater detention, storage, and reuse. The USTs are proposed to be placed underneath road or highway pavements. FRP as one of the emerging structural materials possesses several advantages including high strength-to-weight ratio and excellent corrosion resistance, compared with steel and other conventional materials. The mechanical performance of FRP USTs has rarely been investigated in existing literature; the majority of the existing studies have generally focused on leakage issues and associated environmental problems. This paper presents the results of the first-ever field test on an FRP UST buried underneath a pavement subjected to traffic loads. Sophisticated instruments using optic fiber sensors were installed to measure the responses of the FRP UST. The influences of traffic location and the water storage on the behavior of the FRP UST were investigated. The test results demonstrated the reliability of the FRP UST in resisting the traffic loads. Finally, finite element modelling was conducted to simulate the test results. The insights gained from the field test and the finite element analysis are expected to provide a general guidance on the design of FRP USTs under road pavements for “Sponge City” development.

According to modern structural codes, a design is considered to be adequate if the limit states are not exceeded. For the ultimate limit state, the design value of action effect Ed is required to be less or equal than the design value of ultimate resistance Rd. This ensures, according to the Eurocode, a sufficiently low probability of failure expressed as the target reliability index β. Consequently, the distributions of action effect and of resistance need to satisfy the following conditions: PE>Ed≤Φ+αEβ and PR≤Rd≤Φ−αRβ, where αE and αR, with |α| ≤ 1, are the values of the FORM sensitivity factors. The values of the sensitivity factors αE and αR are suggested, according to EN1990, as −0.7 and 0.8, respectively; for the accompanying actions, the sensitivity factor is recommended as 0.28. In this paper, the dependence of the sensitivity factors for traffic live load, dead load, and resistance on the ratio of traffic load to dead load is studied (which is directly proportional to the maximum span of the bridge). Significantly different sensitivity factors for resistance, dead load, and traffic load, other than proposed by the Eurocode, has been calculated for typical ratio of traffic to dead load. It further showed that, if it is assumed that Ed = Rd and the Eurocode partial safety factors are used, a different design point than the starting point, i.e., Ed = Rd, is obtained.

In many instances, the safety of existing structures can no longer be demonstrated by standard code-based assessments. Reasons for this include changes in the code, changes in the demands on the structures and deterioration. To address this problem, it is common practice to perform a more detailed assessment utilizing advanced models. In this way, many structures can be shown to comply with safety requirements, even if they cannot be verified by standard assessments. The standard code models are often conservatively biased. This leads to designs which include hidden safety. If the reassessment is performed with more advanced models in lieu of standard models, the hidden safety can vanish. Concurrently, the reduced uncertainty of advanced models may compensate this safety reduction. In this paper we investigate this issue on a hypothetical population of existing bridge structures under traffic. We consider that the standard code model is exchanged by an advanced traffic load simulation.

Problems of large settlements and uneven settlements on the road always happen during service stage. Reinforced embankments can reduce these problems. But currently the study on the mechanical properties of reinforced embankments during service stage are so few, and lack of measured data. This study uses numerical simulation and on-site measured data analysis to set up a geogrid creep damage model and traffic load model. Based on the analysis of the mechanical properties of reinforced embankment under the conditions of new test section and widening test section, the influence laws of traffic load amplitude, frequency and driving interval on reinforced embankment are obtained. When the traffic load amplitude is 2q0, there is little difference in settlement between the two test sections, but the settlement ratio gets the maximum value of 0.028 mm/d when the amplitude is 2q0. When the traffic load frequency increases from 1 Hz to 4 Hz, the embankment settlement is in the sudden settlement stage, and the settlement is almost stable after 4 Hz. When the driving interval is greater than 4 s, the rebound value and rebound time are almost stable.

This research aims to assess the effect of temperature gradient developed within the concrete slab of rigid pavement, and to investigate its impact when incorporated with the traffic load, and the heat transfer pattern. The rigid pavement model considers an isotropic, uniform, and linear-elastic schemes to simulate the material properties. A numerical analysis approach was employed using Abaqus software incorporated with the 3D Solid model. The traffic loads were obtained from the field surveys, while the temperature of the slabs was measured directly on the site. The dimension of the rigid panel is 2.75 m in width, 5 m long, slab thickness of 25 cm, and concrete specification of 41.33 MPa. The results showed that the temperature gradient produced a significant impact on stress development within the concrete slab of rigid pavement. It was observed that the temperature gradient during the daytime generated higher stress than at night, with a value reaching the MOR (Modulus of Rupture). The exposure of the rigid pavement to 500C tends to produce a principle slab stress of 2.395 MPa, while 1.31 MPa was developed due to the traffic load. When the two factors were combined, the concrete slab acquired a maximum principle stress of 3.322 MPa, which is close to the MOR of 83.34% fa. These results showed that the pavement is capable of withstanding stress from temperature gradient and traffic load as indicated by the ratio of less than one (1). However, this ratio is high for fatigue failure mitigation purposes, and this reduces the quality of life of the rigid pavement.

Pavements are significant resources of expressway infrastructure. The nation has seen colossal expansion in the vehicle population and expanded hub stacking design during the last decade, leaving its street network overemphasized and prompting untimely disappointment. The kind of weakening present in the asphalt ought to be considered for deciding if it has a useful or underlying inadequacy, so that suitable overlay type and configuration can be created. The structural properties of asphalt are redirection and it is completed by Benkelman Beam & deflectometer test. The evaluation of street conditions is needed to distinguish the explanations behind disintegration before any restoration work is completed. The fundamental boundaries including in the appraisal of street conditions are avoidance and unpleasantness estimation which decided utilizing different test, for example, FWD, Benkelman shaft test, profilometer, and slide obstruction test. This appraisal additionally helps in focusing on the upkeep works as indicated by the necessity. A few procedures are utilized to evaluate the road conditions and contrast and standard standards. In this concentrate on a stretch of road is break down for similar where techniques utilized are visual strategy, Benkelman beam test and slide opposition test. The structural and useful assessment are dissected and created by different specialists. The paper presents an itemized audit of different asphalt exhibitions on primary and utilitarian assessment of adaptable asphalt to inspect the job of components identified with asphalt materials, surface deflection, ecological conditions, sort of traffic and volume of traffic, and to distinguish the constraints and holes in the current information on such examinations. [ABSTRACT FROM AUTHOR]