Add to ORKGThe models that correlate the road characteristics and the operating speed on tangent are studied all around the world. Although the issue of speeds on tangent sections has not been studied extensively, several U.S. and international researchers have studied operating speeds and average running speeds, design speeds, speed limits, and the impact of geometric and traffic measures on speeds. The objective of this experimental study is to get relationships of general validity for the prediction, in phase of project, of the speeds that will be indeed practiced on the infrastructure. The experimental investigation has been conducted employing traffic counters, able to record, for every vehicular passage in both senses: length, instant speed and ...