https://biblio.ugent.be/publication/331076/file/563471.pdf

The influence of traffic flow dynamics on urban soundscapes

Three families of road noise prediction models can be distinguished. Static noise models only consider free-flow constant-speed traffic with uniformly distributed vehicles. Analytic noise models assume that all vehicles are isolated from one another but account for their mean kinematic profile over the network. Micro-simulation noise models relax the hypothesis of no interaction between vehicles and fully capture traffic flow dynamic effects such as queue evolution. This study compares the noise levels obtained by these three methodologies at signalized intersections and roundabouts. It reveals that micro-simulation noise models outperform the other approaches. Particularly, they are able to capture the effects of stochastic transient queues in under-saturated conditions as well as stop-and-go behaviors in oversaturated regime. Accounting for traffic dynamics is also shown to improve predictions of noise variations due to different junction layouts. In this paper, a roundabout is found to induce a 2.5 dB(A) noise reduction compared to a signalized intersection in under-saturated conditions while the acoustic contributions of both kinds of junctions balance in oversaturated regime.

/pdf/improving-noise-assessment-at-intersections-by-modeling-3cm8nqnsi0.pdf

Improving noise assessment at intersections by modeling traffic dynamics

Accounting for traffic dynamics improves noise assessment: Experimental evidence

Urban noise mapping traditionally involves the use of a traffic simulation model, which is often based on the estimation of macroscopic traffic flows. However, intersections and other local traffic management measures are not always modeled correctly. It is well known that the specific deceleration and acceleration dynamics of traffic at junctions can influence local noise emission. Finding the best strategy for using traffic modeling results in noise mapping is a current topic of research in the IMAGINE project. In this paper, a case study is presented, consisting of a large set of microscopic traffic simulations and associated noise emission calculations, which provides some insight into the specific dynamics of the noise emission near different types of intersections. It will be shown that it is possible to refine current traffic noise prediction models, based on macroscopic traffic simulation, using a correction on the average vehicle emission, aggregated in lane segments. A spatial approach should be used, in which inbound and outbound lanes are divided into deceleration, queuing, stopline and acceleration zones. Results from regression analysis on the numerical simulations indicate that meaningful relations between noise corrections and traffic flow parameters such as traffic intensity and composition can be deduced.

https://biblio.ugent.be/publication/394261/file/587492.pdf

Masanori Fujimoto

Papers

A model of interrupted road traffic noise