Pierre-Marie-Jérôme Trésaguet
Pierre-Marie-Jérôme Trésaguet | |
---|---|
Born | |
Died | 1796 (aged about 80) |
Known for | Establishing the first scientific approach to road building |
Scientific career | |
Fields | Engineering, road building |
Institutions | Corps des Ponts et Chaussées, Paris; chief engineer, Limoges |
Pierre-Marie-Jérôme Trésaguet (15 January 1716 – 1796) was a French
Trésaguet was born in Nevers, the youngest son from a family of engineers. He began his career as a sub inspector in the Corps des Ponts et Chaussées (Bridges and Highways Corps), in Paris. He later moved to Limoges, Haute-Vienne as chief engineer in 1764. In 1775 he was appointed inspector general of roads and bridges for all of France. He published a paper describing his road building methods.
Method of road building
First of all, an earth foundation was excavated parallel with but about ten inches below the finished surface of the new road. This was convex in cross section to encourage water to drain off the finished surface.
Next, large stones were laid on edge and any protruding pieces on their upper edges broken off to leave an even surface. This stone foundation was covered with a second course of smaller rounded stones.
Finally, a third layer of hard broken stone, (about the size of walnuts) was spread by a shovel to produce the surface layer.
This system was used continuously in France from 1775 until 1820 when the country changed to the cheaper Macadam method.
See also
References
- Arthur G. Bruce, Highway Design and Construction, International Textbook Company, Scranton, Pennsylvania (1934)