Design Criteria for Improving Safety Performance of Rural Intersections

This paper, on the one hand, aims to identify significant crash risk factors at unsignalized three-leg intersections connecting rural two-lane two-way roads and minor roads with a STOP control on the approaches (3ST) and, on the other, to make adjustments to the Highway Safety Manual (HSM) procedure, fine-tuning its Safety Performance Function (SPF) based on observation of the local context. Over an 8-year period of study, a total of 240 crashes on 35 3ST intersections were observed, with no geometric-infrastructure adjustments or changes in the Annual Average Daily Traffic (AADT) and surrounding context noted at the intersections investigated. To obtain reliable results, the study period was divided into two groups: (a) 5 years to calibrate a new SPF, and (b) the remaining 3, not included in the first dataset, were used to validate the results. A negative binomial regression model was adopted to calibrate the new SPF. It was found that the AADT on the major and minor roads, the intersection skew angle, the co-occurrence of left and right-turn lanes on the major roads, and lighting seriously affect the crash scenario

Surface monitoring of road pavements using mobile crowdsensing technology

Pavement-surface characteristics should be considered during road maintenance for safe and comfortable driving. A detailed and up-to-date report of road-pavement network conditions is required to optimize a maintenance plan. However, manual road inspection methods, such as periodic visual surveys, are time-consuming and expensive. A common technology used to address this issue is SmartRoadSense, a collaborative system for the automatic detection of road-surface characteristics using Global Positioning System receivers and triaxial accelerometers contained in mobile devices. In this study, the results of the SmartRoadSense surveys conducted on Provincial Road 2 (SP2) in Salerno, Italy, were compared with the Distress Cadastre data for the same province and the pavement condition indices of different sections of the SP2. Although the effectiveness of the crowdsensing-based SmartRoadSense was found to vary with the distress type, the system was confirmed to be very efficient for monitoring the most critical road failures

Multiobjective railway alignment optimization using ballastless track and reduced cross-section in tunnel

The increasing need for railway planning and design to connect growing cities in inland mountainous areas has pushed engineering efforts toward the research of railway tracks that must comply with more restrictive constraints. In this study, a multiobjective alignment optimization (HAO), commonly used for highway projects, was carried out to identify a better solution for constructing a high-speed railway track considering technical and economic feasibilities. Then, two different and innovative scenarios were investigated: an unconventional ballastless superstructure, which is more environment-friendly than a gravel superstructure, and a reduced cross-section in a tunnel, which enables a slower design speed and then, less restrictive geometric constraints and earthmoving. The results showed that the first solution obtained a better performance with a slight increase in cost. Moreover, both scenarios improved the preliminary alignment optimization, reducing the overall cost by 11% for the first scenario and 20% for the second one

Optimization of Enzymatic Biochemical Logic for Noise Reduction and Scalability: How Many Biocomputing Gates Can Be Interconnected in a Circuit?

We report an experimental evaluation of the "input-output surface" for a biochemical AND gate. The obtained data are modeled within the rate-equation approach, with the aim to map out the gate function and cast it in the language of logic variables appropriate for analysis of Boolean logic for scalability. In order to minimize "analog" noise, we consider a theoretical approach for determining an optimal set for the process parameters to minimize "analog" noise amplification for gate concatenation. We establish that under optimized conditions, presently studied biochemical gates can be concatenated for up to order 10 processing steps. Beyond that, new paradigms for avoiding noise build-up will have to be developed. We offer a general discussion of the ideas and possible future challenges for both experimental and theoretical research for advancing scalable biochemical computing

BIM Reverse Engineering: Digital Transformation of Existing Roads

The raising of the transport infrastructure sector through the digital transformation of roads is a factor for sustainable and intelligent development of the Country, in order to create safer, cheaper, better-used and fruited infrastructures generating data and services for a better travel experience for citizens, facilitating freight transport and helping to determine a technology-friendly ecosystem for businesses. A specific need for the digital transformation of roadways consists in acquiring the geometric features of existing roads. The process is known as reverse engineering, or Scan to BIM, and generates object models that can be implemented and usable on BIM platforms. BIM is the tool that best suits these operational needs in the various fields and in all the advancing stages of the life cycle of the work, from conception to disposal. The case study shows the solid parametric modeling of the rural road SP430 "Cilentana" (SS18VAR), one of the main route for the Southern areas of Campania Region. The BIM platform provides the ability to extract road alignment, profiles and cross sections from the 3D model at any time. Processes can be dynamically updated as a result of any modifications made to the model for extraordinary adjustments and/or maintenance of the road. Autodesk Software packages Civil 3D and Infraworks were used in a combined approach

BIM-Based Design for Road Infrastructure: A Critical Focus on Modeling Guardrails and Retaining Walls

Although building information modeling (BIM) has been widely adopted in the building industry for several decades, the use of BIM in the context of transportation infrastructure has been slow in terms of both adoption and application. Industry and academia are increasingly making efforts to adopt BIM for other non-building civil infrastructure but, so far, there has not been a comprehensive review of these efforts specifically regarding transportation. This paper explores BIM implementation in an infrastructure design project. An Autodesk ® BIM-based tool, Civil 3D, is proposed as a potential BIM tool platform. This paper also focuses on modeling specific road elements not editable from the standard library, such as guardrails and retaining walls, as well as proposing different solutions using Revit and Subassembly Composer and analyzing the interoperability among BIM-based tools

I-BIM based approach for geotechnical and numerical modelling of a conventional tunnel excavation

Very recently the Building Information Modeling (BIM) design approach has landed in the infrastructure field, giving life to the I-BIM, the BIM for the infrastructures, including geotechnical underground works likes tunnels. In this framework, the present paper shows an application in the field of geotechnical engineering of the BIM based design approach to the case of an underground line. It is a tunnel excavated by means of traditional method, currently under construction. The project defines, in a central BIM model, a detailed tunnel structure model integrated with geological-geotechnical information for the definition of the subsoil 3D model. Once the BIM model of the tunnel stretch under study was completely defined, it was imported into a finite element (FE) model to perform deformation analyses. Thus, BIM-to-FEM-to-BIM interoperability was exploited in order to verify the maturity level of the BIM approach in the field of application for geotechnical infrastructures. Finally, the BIM fourth dimension (4D) was also implemented in the central model for the time management of the tunnel excavation process, synchronized with the numerical model. The BIM based procedure proposed in the present work can be considered as a case study in the technical literature of I-BIM for tunnels, putting in evidence limitations and advantages: i) a high level of BIM maturity was not yet achieved in the infrastructures field; ii) the BIM-to-FEM interoperability seems to be not fully effective and many operations still require the manual intervention; iii) the FEM-to-BIM interoperability brings back all geotechnical choices and hypothesis to the central BIM model, linking the models into a continuously interoperable circuit; iv) an important part of the design of civil infrastructures consists of addressing geotechnical aspects, hence the inclusion of ground conditions and geotechnical data into the BIM model can improve the quality and the usefulness of the model, not only during the design phase but also, and in particular, during the construction and the lifecycle management of the infrastructure, as a support to decision making process especially in urban context

Rheological properties comparing hot and cold bituminous mastics containing jet grouting waste

The use of reclaimed asphalt pavement is a practice that is adding significant environmental value to road technologies, not only due to the reduction of materials sent to landfill but also because of the mechanical properties of the reclaimed asphalt (RA) that can be reused. This research focuses on the rheological properties of hot and cold bituminous mastics made up as follows: (1) hot mastics mixed with limestone filler (LF) and bitumen, (2) hot mastics, made from bitumen mixed with jet grouting waste (JW), a mixture of water, cement, and soil derived from land consolidation work in underground tunnels, and (3) hot mastics mixed with LF and JW as filler and bitumen. Three different ratios (0.3, 0.4, and 0.5) of filler per unit of neat bitumen (B50/70) were studied. The same number was used for mixing cold mastics, by using an appropriate laboratory protocol designed since the adoption of a cationic bituminous emulsion. A total of 18 mastics were prepared and investigated. The comparison was carried out using the frequency sweep (FS) test, analysing shear modulus G∗, applying the multistress creep and recovery (MSCR) test (40°C and 60°C) as well as the delta ring and ball (ΔR&B) test, focusing on two main issues: (1) the stiffening effect caused by the filler type used for mixing each mastic, and (2) a comparison, in terms of stiffening effects and nonrecoverable creep compliance (Jnr) of hot and cold mastic performance to highlight JW reuse in mastics. The results showed that the best G∗ performance at test temperatures higher than 30°C is given by cold mastic after 28 days of curing time when JW is added to LF and bitumen. The lowest Jnr value was 40°C and 60°C for the same mastic

Influence of fly ashes as alternative filler in asphalt mixtures

This study defined the mechanical/volumetric properties and the environmental compatibility of bituminous mixtures containing fly ashes as alternative of traditional limestone filler. The research study is articulated in different steps as follows: a) characterization of fly ashes according to UNI EN 1303 Standard; b) environmental compatibility analysis of mastics containing fly ashes by using a leaching test; c) stiffness evaluation of the mastics containing limestone and fly ash filler by static testing, as Delta Ring and Ball Test, and dynamic testing, as Frequency Sweep Test; d) mechanical and volumetric characterization of asphalt concrete containing fly ashes and limestone filler starting from a phase of mix design of hot mix asphalt mixtures. The characteristics of rigidity of the bituminous conglomerates has been evaluated using the HMA optimal mixture analysis through a dynamic test with a sinusoidal load. Then, the ability of two different HMA to endure a permanent deformation was evaluated by a Repeated Load Axial Test. The results has shown that mixtures of Hot Mix Asphalt with flying ashes as filler, compared to Hot Mix Asphalt containing limestone filler, is preferred in terms of mechanical performances and relevant environmental compatibility evaluated with a leaching test

Ship tracking for maritime traffic management via a data quality control supported framework

Ship trajectory in maritime surveillance videos provides crucial on-site traffic information (e.g., ship speed, traffic volume, density) to help maritime traffic situation awareness and management in the smart ship era. To that aim, many focuses are paid to track ships from maritime videos by exploring distinct visual features from maritime images, which may fail under complex maritime environment interference (occlusion, sea clutter interference, etc.). The study proposes a novel video-based ship tracking framework with the help of Multi-view learning model and data quality control procedure. First, we obtain raw ship positions from maritime images with particle filter and Multi-view learning models. Then, a data quality control procedure is implemented to suppress ship tracking outliers with the help of Kalman filter. Finally, we verify our proposed model performance on three typical maritime traffic situations (ship occlusion, sea clutter interference and small ship tracking)