Search results

The purpose of this study was to investigate the likely causes of failure of some sections of road pavements in Ajaokuta, Northcentral Nigeria. This was achieved through a geotechnical assessment of subgrade soils in affected areas.

The methods entailed field and laboratory methods and statistical analysis. Subgrade soil samples were retrieved from a depth of 1,000 mm beneath the failed portions using a hang auger. The soils were analyzed for natural moisture content (NMC), Atterberg limit (liquid limit, plastic limit and linear shrinkage), grain size distribution, compaction and California bearing ratio (CBR), respectively.

The results of the geotechnical tests ranged from NMC (12.5%–19.4%), sand (84%–98%), fines (2%–16%), LL (16.0%–32.2%), PL (17%–27.5%), LS (2.7%–6.4%), PI (2.5%–18.4%), maximum dry density (1756 kg/m2–1961 kg/m2), optimum moisture content (13.2%–20.2%), unsoaked CBR (15.5%–30.5%) and soaked CBR (8%–22%), respectively. Pearson’s correlation coefficient performed on the variables showed that some parameters exhibited a strong positive correlation with r2 > 0.5.

Funding was the main limitation.

Comparing the results with Nigerian standards for road construction, and the AASHTO classification scheme, the subgrade soils are competent and possess excellent to good properties. The soils also exhibited very low plasticity, a high percentage of sand, high CBR and low NMC, which implies that it has the strength required for road pavement subgrades. The likely causes of the failures are, therefore, due to the use of poor construction materials, technical incompetence and poor compaction of sub-base materials, respectively.

The China’s Belt and Road Initiative (BRI, hereafter) has reenergized the Silk Road concept, with most literature focusing on the political and economic effects of the BRI. While certain aspects of the Digital Silk Road (DSR), digital component of BRI, have been researched, much less focus has been placed on the technological development, tech transfer and information diffusion aspects of the BRI. The aim of this study is to investigate the opportunities, issues and critiques that have arisen as a result of the Belt and Road Initiative’s implications on innovation, knowledge transfer and dissemination.

Research in its nature is descriptive. Literature reviews are a significant part of the development of a field. Therefore, secondary sources were considered.

The literature and the study have highlighted several opportunities, problems and criticism that decision-makers and the relevant agencies and institutions should take into account when deciding how to move forward with BRI and its digital component DSR.

This paper contributes to the research literature on BRI and its subset DSR’s impacts on innovation, knowledge transfer and information diffusion. In fact, the DSR’s primary aim is to strengthen international cooperation in the digital economy. Furthermore, digital platforms now play a significant role in global trade, emphasizing the necessity of DSR.

This Chapter examined the development of sustainable road infrastructure in Ghana including transportation roads, and laws, regulations, and frameworks. The Ministry of Transport (MoT) and the Ministry of Roads and Highways (MRH) are responsible for the development of transportation infrastructure and related services. The Department of Urban Roads (DUR) is responsible for facilitating the movement of people, goods, and services and promoting economic and social development of urban regions. The Metropolitan and Municipal Assemblies established road centres to manage, construct, and maintain city roads, the Ghana Road Fund (GRF) was established to provide funding for the maintenance of Ghana’s road network, and the Koforidua Training Centre (KTC) was established in 2007 to provide management and project implementation staff with professional development and hands-on training. The current road length is 71,418 km, including 42,045 km of feeder roads, 14,873 km of trunk roads, and 14,500 km of urban roads. The budget for preventative maintenance is expected to rise year over year. Road infrastructure development (RID) can lead to positive societal outcomes, such as financial gains, employment opportunities, social support systems, equal rights for women and men, increased productivity, and less pollution, but it can also have unintended consequences such as deteriorating air and water quality, noise and vibration, soil erosion and sedimentation, disruption of essential services, confusion between drivers and pedestrians, changes to the landscape and habitat, and eminent domain takings. Environmental and social evaluations of development projects in Ghana must comply with several laws and regulations, and there is no unified sustainability policy or guideline in place to regulate the development of highway infrastructure projects. Resettlement is expected to help those who have been displaced by development initiatives and the Environmental Protection Agency Act of 1994 provides the authority to authorize facilities, set performance standards, and ensure compliance with standards and regulations. The Forestry Policy focusses on reducing deforestation and enhancing ecological and social commitment of forest areas, while the method for managing cultural property requires investigating and cataloguing damaged objects. Sector medium-term development plan (SMTDP) provides solutions for enhanced RID access, while the strategic environmental assessment (SEA) incorporates ecological factors into the Ghana Integrated Transport Plan. The resettlement policy framework (RPF) coordinates laws, rules, and procedures to manage road infrastructure projects and establishes criteria for determining eligibility and entitlement. The Directorate of Policy and Planning of the MRH is responsible for managing road safety and the environment, while the Directorate of Monitoring and Evaluation oversees Monitoring and Evaluation of road projects. The Ghana Highway Authority’s (GHA) four-person Road Safety and Environmental Management Unit (EMU) is responsible for addressing social and environmental issues associated with the feeder roads zone. Sustainable development (SD) has not received much attention from the Ghanaian government, with state-owned institutions prioritizing economic growth over social benefits and environmental preservation. Local governments should include a sustainability framework in their strategic planning for the successful execution of sustainable projects.

Road transport is an important sector of the economy, however, its negative impacts on the environment, human health and sustainability of potential economic growth are significant. Transport externalities tend to be neglected within the market process. The damage generated through significant externalities of road transport in Czechia was identified, based on unique data processing, to reach almost 3.5 billion € annually. This chapter presents an overview of internalization taxes and fees, their current rates and generated receipts. If excise duty is disregarded as fundamentally unsuitable for the internalization of externalities, then the receipts from other applied taxes and fees, particularly the road tax, seem to be insufficient. Although economic growth is encouraged, its form is not sustainable in view of the rising phase of the Kuznets curve and the related irreversible environmental impacts.

The purpose of this study is to investigate the influence of institutional dynamics on road accidents and whether this relationship is moderated by information and communication technology (ICT).

The study adopted a quantitative approach with 133 respondents. Research hypotheses were tested in AMOS version 21. In addition, moderated regression analysis was used to test the moderating role of ICT on the relationship between institutional dynamics and road accidents.

The results show that vehicle maintenance, policy enforcement, safety culture, driver training and driver management positively influence road accidents. Moreover, the study established that ICT moderates the relationship between institutional dynamics and road accidents.

The results of this study serve as a practical guideline for policymakers in the road haulage sector. Managers may gain insights on how to design effective interventions to reduce road accidents.

This research contributes to the existing body of knowledge by exploring previously unexplored moderating paths in the relationship between institutional dynamics and road accidents. By highlighting the moderating role of ICT, the study sheds new light on the institutional dynamics that influence road accidents in the context of road haulage companies.

Road freight transportation companies need to take advantage of information and communication technologies to develop capabilities. This study proposes a framework to guide road freight transportation companies to achieve data visibility in their operations by developing such capabilities. By proposing this framework, this research contributes to literature and practice, highlighting the capabilities and the respective supporting technologies for improved data visibility in road freight transportation.

A mixed-method approach is used to develop the framework, considering three methodological steps. In phase 1, the capabilities are identified in the literature and validated by experts. In phase 2, an empirical assessment of cause–effect relationships between capabilities is performed using a multiple case study and DEMATEL. Lastly, in phase 3, an analysis of the cause model and significant associations is conducted to enable the development of the framework. In addition, the proposed framework was validated by the experts interviewed.

The results provide a framework that explains the link between the technology-enabled data visibility capabilities in road freight transportation operations. In addition, a pathway was established that road freight transportation companies could follow to achieve data visibility in their operations by developing such capabilities.

This work develops the first framework that provides a path for data visibility in road freight transportation operations from adopting certain technologies. The insights are compelling for researchers and practitioners to optimize the decision-making process for adopting technologies and developing capabilities related to data visibility.

Transport infrastructure in most countries is owned and maintained either by public authorities, private organisations, or individuals. However, in Sweden, about 50 per cent of the road network is owned and maintained by civic road associations. By using the analytic notion of commoning, this chapter seeks to explore how road maintenance is organised and in what ways civic participation is contributing to infrastructure maintenance. Through interviews with representatives of civic road associations in Vellinge municipality and municipal representatives, we conclude that property owners are being commoned, that is, they are obliged to be a member of the civic road association in the neighbourhood where they own property. This means that property owners are given the opportunity to collectively decide on matters of road infrastructure, including maintenance and investments. Each civic road association is also acting as an organisational collective, demanding or pressuring the municipality and its politicians to reform subsidies and the organisation of ownership of roads and responsibility for their maintenance. As a single property owner, this is difficult, but as an organisational collective, in a civic road association, they have a voice. As a citizen, local municipal election offers opportunities to push for change, but at these institutionalised moments of democracy, road infrastructure issues compete with other issues. Election campaigns rarely target road maintenance, although Vellinge seems to be an exception here. Nevertheless, as citizenship is built around the provision of universal and evenly distributed infrastructure, crumbling infrastructure in different parts of the municipality tends to raise concerns over equal access and opportunities – and also differentiated citizenships.

This research aims to present a novel cooperative control architecture designed specifically for roads with variations in height and curvature. The primary objective is to enhance the longitudinal and lateral tracking accuracy of the vehicle.

In addressing the challenges posed by time-varying road information and vehicle dynamics parameters, a combination of model predictive control (MPC) and active disturbance rejection control (ADRC) is employed in this study. A coupled controller based on the authors’ model was developed by utilizing the capabilities of MPC and ADRC. Emphasis is placed on the ramifications of road undulations and changes in curvature concerning control effectiveness. Recognizing these factors as disturbances, measures are taken to offset their influences within the system. Load transfer due to variations in road parameters has been considered and integrated into the design of the authors’ synergistic architecture.

The framework's efficacy is validated through hardware-in-the-loop simulation. Experimental results show that the integrated controller is more robust than conventional MPC and PID controllers. Consequently, the integrated controller improves the vehicle's driving stability and safety.

The proposed coupled control strategy notably enhances vehicle stability and reduces slip concerns. A tailored model is introduced integrating a control strategy based on MPC and ADRC which takes into account vertical and longitudinal force variations and allowing it to effectively cope with complex scenarios and multifaceted constraints problems.

This study aimed to explore the spatial accessibility dynamics of urban parks and their driving forces from 1901 to 2010 in terms of the dynamic relationships between spatial morphology and road networks, taking Nanjing City as an example.

This study mapped and examined the spatiotemporal distribution of urban parks and road networks in four time points at Nanjing: the 1910s, 1930s, 1960s and 2010s, using the analysis methodology of spatial design network analysis, kernel density estimation and buffer analysis. Two approaches of spatial overlaying and data analysis were adopted to investigate the accessibility dynamics. The spatial overlaying compared the parks' layout and the road networks' core, subcore and noncore accessible areas; the data analysis clarified the average data on the city-wide and local scales of the road networks within the park buffer zone.

The analysis of the changing relationships between urban parks and the spatial morphology of road networks showed that the accessibility of urban parks has generally improved. This was influenced by six main factors: planning implementation, political policies, natural resources, historical heritage and cultural and economic levels.

The results provide a reference for achieving spatial equity, improving urban park accessibility and supporting sustainable urban park planning.

An increasing number of studies have explored the spatial accessibility of urban parks through the relationships between their spatial distribution and road networks. However, few studies have investigated the dynamic changes in accessibility over time. Discussing parks' accessibility over relatively long-time scales has practical, innovative and theoretical values; because it can reveal correlational laws and internal influences not apparent in short term and provide reference and implications for parks' spatial equity.

To proactively draw efficient maintenance plans, road agencies should be able to forecast main road distress parameters, such as cracking, rutting, deflection and International Roughness Index (IRI). Nonetheless, the behavior of those parameters throughout pavement life cycles is associated with high uncertainty, resulting from various interrelated factors that fluctuate over time. This study aims to propose the use of dynamic Bayesian belief networks for the development of time-series prediction models to probabilistically forecast road distress parameters.

While Bayesian belief network (BBN) has the merit of capturing uncertainty associated with variables in a domain, dynamic BBNs, in particular, are deemed ideal for forecasting road distress over time due to its Markovian and invariant transition probability properties. Four dynamic BBN models are developed to represent rutting, deflection, cracking and IRI, using pavement data collected from 32 major road sections in the United Arab Emirates between 2013 and 2019. Those models are based on several factors affecting pavement deterioration, which are classified into three categories traffic factors, environmental factors and road-specific factors.

The four developed performance prediction models achieved an overall precision and reliability rate of over 80%.

The proposed approach provides flexibility to illustrate road conditions under various scenarios, which is beneficial for pavement maintainers in obtaining a realistic representation of expected future road conditions, where maintenance efforts could be prioritized and optimized.