Several members of the Swiss family Grubenmann were famous as carpenters and civil engineers in the 18th century. The sons were innovators in bridge construction.
The brothers were village carpenters in Teufen. The principal structures are known to be:
Crossing of the RhineatSchaffhausen in two spans of 52 m and 59 m respectively, (Hans Ulrich, 1757);
A single-span of 67 m at Reichenau, (Johannes, 1757);
Crossing of the LimmatatWettingen, a 60 m span thought to be the first use of a true arch in a timber bridge, (Hans Ulrich and Johannes, 1778).
Very few of their bridges have survived, those at Schaffhausen and Wettingen being burnt by the French in the war of 1799, but their designs were influential, making use of novel combinations of arches and trusses. The surviving bridges include: