The Lamme Bridge is a road bridge over the Rhine-Schie Canal. This bridge is part of the N206 and is important for the connection to the A4 motorway. The narrow bridge has been a bottleneck for traffic for many years, in addition, the bridge is often open because the headroom for ships is only 2.75 meters.
A concrete structure will soon take its place, which together with the new Trekvliet bridge forms an important link in the Rijnland Route project, which also includes the recently opened Corbulo tunnel. This route connects the A4 with the A44 and should provide better traffic flow around Leiden and Katwijk. The new Lammebrug will soon be 5.5 meters high. A fixed construction, so traffic will no longer have to wait for an open bridge as is currently the case.
Preparatory works
Since vehicular traffic must be able to continue as normal during the works, a temporary bridge had to be built over the Rijn-Schie Canal, a steel structure resting on ten heavy pillars consisting of tubular piles. In order to place those piles deep into the ground, Van Schie – commissioned by Gebr. de Koning – carried out pre-drilling from a pontoon formation. A precision job, performed with an ABI TM 15/16 drilling crane that can drill to a depth of 16 meters. And since there were also various obstacles and an old casing pipe in the ground at the site of the drilling, these had to be rendered harmless first by “crushing” them. The floating work platform consisted of so-called container pontoons, stable enough for the 55-ton drilling crane.
