Search results for "structural"
showing 10 items of 5047 documents
Using Genetic Algorithms for Optimizing the PPC in the Highway Horizontal Alignment Design.
2016
Various studies have emphasized the interesting advantages related to the use of new transition curves for improving the geometric design of highway horizontal alignments. In a previous paper, one of the writers proposed a polynomial curve, called a polynomial parametric curve (PPC), proving its efficiency in solving several design problems characterized by a very complex geometry (egg-shaped transition, transition between reversing circular curves, semidirect and inner-loop connections, and so on). The PPC also showed considerable advantages from a dynamic perspective, as evidenced by the analysis of the main dynamic variables related to motion (as well as rate of change of radial accelera…
Using a hazard-independent approach to understand road-network robustness to multiple disruption scenarios
2021
Abstract A range of predictable and unpredictable events can cause road perturbations, disrupting traffic flows and more generally the functioning of society. To manage this threat, stakeholders need to understand the potential impact of a multitude of predictable and unpredictable events. The present paper adopts a hazard-independent approach to assess the robustness (ability to maintain functionality despite disturbances) of the Sioux Falls network to all possible disruptions. This approach allows understanding the impact of a wide range of disruptive events, including random, localised, and targeted link failures. The paper also investigates the predictability of the link combinations wh…
Assessment of proneness to distraction: English adaptation and validation of the Attention-Related Driving Errors Scale (ARDES) and cross-cultural eq…
2016
Abstract Prior research developed the Attention-Related Driving Errors Scale (ARDES), a 19-item questionnaire aimed at evaluating the drivers’ predisposition to attentional error, and also provided validity evidence of ARDES measures across two countries: Argentina and Spain. In the current work we adapt the Spanish version of the ARDES to the English language and the culture, traffic regulations and driving habits of the UK, and then provide new evidence of the cross-cultural equivalence of the scale. First, an improved forward and backward translation design was used to translate the Spanish ARDES into English. A committee-approach review process was also performed during the translation …
The social acceptance of airport expansion scenarios: A factorial survey experiment
2020
Abstract Against the background of growing aviation and protests against air traffic in many countries, we employ a factorial survey experiment to examine the social acceptance of airport expansion scenarios in two European cities located near the international airports of Frankfurt (Germany) and Zurich (Switzerland), respectively. In our experiment, respondents evaluated short descriptions of airport expansion scenarios that varied in several impact attributes. The experiment helps to disentangle to what extent environmental impacts (aircraft noise), economic impacts (job creation), participatory justice aspects (participation opportunities), and distributive justice aspects (noise distrib…
Schedule-Based Integrated Intercity Bus Line Planning via Branch-and-Cut
2018
This work addresses integrated line planning for intercity bus lines, which differs in several respects from line planning in public transit. Passengers in intercity transportation decide on specific timetabled services to get to their destination. This is a contrast to an urban setting with higher frequencies, where it is generally sufficient to choose a line. Furthermore, intercity bus transportation in deregulated markets is usually characterized by fierce competition within and across modes. Customers are highly sensitive to price, time of day, duration, convenient access to stations, and service quality. Hence, bus line operators need to decide thoroughly on every single timetabled se…
Branch-and-Price-and-Cut for the Periodic Vehicle Routing Problem with Flexible Schedule Structures
2019
This paper addresses the periodic vehicle routing problem with time windows (PVRPTW). Therein, customers require one or several visits during a planning horizon of several periods. The possible visiting patterns (schedules) per customer are limited. In the classical PVRPTW, it is common to assume that each customer requires a specific visit frequency and offers all corresponding schedules with regular intervals between the visits. In this paper, we permit all kinds of schedule structures and the choice of the service frequency. We present an exact branch-and-price-and-cut algorithm for the classical PVRPTW and its variant with flexible schedules. The pricing problems are elementary shortes…
Performance of a sustainable asphalt mix incorporating high RAP content and novel bio-derived binder
2019
The recent drive to find ways to increase sustainability and decrease costs in asphalt paving has led researchers to find innovative ways to incorporate more recycled materials and bio-derived binders into mixes with varying success. A new novel bio-derived binder made from refined pine chemistry stabilised with a polymer can increase the sustainability of asphalt mixes while maintaining pavement performance. Laboratory performance testing was conducted on asphalt mixes containing 50% Reclaimed Asphalt Pavement (RAP) by mix weight and the novel bio-derived binder. Results show that the bio-derived binder outperforms the conventional 50/70 pen grade binder mixes with respect to resistance to…
Intrinsic adhesive and cohesive assessment of the moisture sensitivity of bio-rejuvenated recycled asphalt binders
2019
Alternative binders not derived from fossil fuels, known as biobinders, are opening new paths for multiple applications in road infrastructure. Biobinders, usually produced from bio-oils obtained from the processing of biomass and industry by-products, are tuneable materials whose properties can be adjusted to meet specific targets. For this reason, an interesting approach is to couple biobinders with Reclaimed Asphalt (RA) by taking advantage of their rejuvenating properties to design bio-asphalt mixtures with high-content RA and no additional virgin bitumen. Recent research has proven the feasibility of this approach through validation at full-scale (BioRePavation project). However certai…
Analysis of Kinematic Parameters and Driver Behavior at Turbo Roundabouts
2018
This study focuses on both vehicle kinematic parameters (speed and acceleration) and behavior parameters (critical interval and follow-up time) of drivers at turbo-roundabouts. Empirical evaluations of such parameters can be helpful in calibrating traffic microsimulation models or assigning behavior parameters to closed-form capacity models in turbo-roundabouts (gap-acceptance capacity models) and are also related to evaluation of vehicles pollutant emissions. The research was based on traffic process observed in the first turbo-roundabout implemented in the city of Maribor in Slovenia. In 2016 a great number of traffic samples were taken with high-frame-rate video recordings [>50 frames pe…
“Pédaler en toute sécurité”: The Cycling Behavior Questionnaire (CBQ) in Belgium – A validation study
2021
Abstract Introduction: During the last few years, the use of behavioral questionnaires for assessing risky behaviors of road users different from motor-vehicle drivers has grown considerably in applied research for road safety. In this regard, recent tools such as the Cycling Behavior Questionnaire (CBQ) are gaining ground, being adapted and tested in further languages, thus getting useful to address the case of countries whose language is different to the English and Spanish. Therefore, and in order to extend the use of the CBQ, this study aimed (i) to develop the validation of the CBQ to the French and Dutch languages, in order to cover the population of Belgian cyclists and (potentially)…