First pilot phase
During the months of February, March and April the first pilot tests foreseen in the BrennerLEC project have taken place. These tests have been organized mainly with the purpose of verifying the correct operation of the several hardware equipment installed in correspondence of the test sites, both as far as the electronic signage for the drivers is concerned as well as the automatic traffic and air quality monitoring stations.
The first field test covers the stretch between Trento South – Rovereto South in direction south, and has been performed in some days with heavy traffic with the aim of relieving traffic congestion along this highway stretch. During these first test session, the speed limit applied to light vehicles has been decreased from 130 km/h to 110 km/h before the appearance of tailback, with the aim to empirically verify if this measure is in the condition to enhance the stability conditions of traffic and reduce the entity and the duration of traffic jams.
Similar pilot activities will be repeated during the summer time, in particular during the week-ends in which the transit tourist flows are maximum. During the days with heaviest traffic, the speed limits will be further reduced up to 90 km/h and in some limited cases the emergency lane will be temporarily used as additional transit lane. This trial will continue during the whole 2017, with a further increase of test sessions during the Christmas time and the first months of 2018. The results will be used to better adjust the second test phase which will roughly start in March 2018.
The second field test covers the stretch between Egna / Ora and S.Michele in both directions. The first tests have tried to decrease the normal speed limits first to 110 km/h and then up to 100 km/h. Differently from the Trentino test bed, the reduction of speed limits is not directly related to traffic conditions, but is functional to the assessment of the air quality conditions near the highway.
In this field stretch, in the period between May 2017 and April 2018 the speed limit of 100 km/h will be dynamically alternated with the conventional speed limit of 130 km/h as a function of a pre-defined calendar which will be however updated underway as a function of the first empirical tests obtained. The objective is to obtain data for a number of hours that is statistically sufficient during an entire solar year: this is necessary in order to obtain first objective and quantitative indications of the possible environmental benefits that it is possible to obtain in the different seasons of a year thanks of this measure according to the reference environmental indicators. The duration of each test session can change from case to case, and approximately it will have a duration between eight and twenty-four hours. The results obtained in this first pilot phase will be used to better organize the following pilot activities, and above to start understanding how to manage the dynamic activation of the speed limits as a function of the current and predicted air quality conditions.