Evaluation of Transverse Thermoplastic Pavement Markings for Speed Reduction in Costa Rica

Author(s): Javier Zamora-Rojas, Didier Eduardo Fonseca-Obando

Slidedeck Presentation:

4C - Zamora


In an effort to reduce vehicle speeds in highway sections of the national road network, LanammeUCR at the University of Costa Rica is coordinating research on low-cost road safety infrastructure countermeasures. In 2010-2011, the performance of transverse pavement markings in Canada had been studied as a speed-reduction countermeasure for intersections in the City of Fredericton, New Brunswick. The evaluation of transverse pavement markings in Costa Rica was based on the experience and results of the project undertaken in Canada.

Transverse pavement markings were proposed at three specific locations in Costa Rica's central metropolitan area, including two different marking designs. The purpose of the markings at two urban highway locations was to create such an effect on drivers that will give them the feeling of driving faster as going through the speed zone encouraging drivers to reduce their speeds. A second pattern was designed to alert drivers of an upcoming school zone in a rural mountainous two-lane highway. The use of double-layered thermoplastic material added a noticeable vibration effect, mainly for passenger vehicles.

A before-and-after statistical study was proposed to measure the effectiveness of the markings based on speed data collected using a digital speed radar. Results distinguished between the two patterns at the three study road sections, and the lasting effect over time. Based on statistical analyses, average speed reductions were more noticeable at the end of the speed zone and downstream at the three sites, achieving speed reductions of up to 18%, similar to the findings in the project in Fredericton. Operating speed reductions ranged 2-17% in all three sites. In terms of the effect over time, there is no evidence of a novelty effect during the first 6 months after the installation of the markings. A similar effect was observed at the intersections in Fredericton.