Facts & Figures

Construction

The Cabauw mast is build as a steel cylinder with a diameter of 2 m. The mast is founded on a strong concrete floor in the basement of the small building at the foot of the mast. The floor is supported by concrete piles that rest on a solid sandy layer. The top platform is at 213 m above the surface.

The construction method was simple as well as ingenious: 47 cylinders each of approximately 5 m length and 4000 kg were prefabricated, galvanized and painted in the factory. On site these elements were mounted on top of eachother, somewhat like a big Meccano construction box. At the height of 50, 100, 170 and 210 m resp. guy wires are attached to tower and secure the mast in three directions. These guy wires (steel cables) are 37 mm in diameter and have breaking strain of 115000(?) kg each. The guy wires are pre-strained at 23000 kg, and have a maximum strain strength of 46000 kg.

The first pile was driven into the soil on 21st of October 1969, the last one of the 58 in total 7 days later on 28th of October. Next the concrete foundation of the mast was build, and the first cylinder section was installed on 21st of April 1970. On 6th of August the section at 200 m was put into its position. The top section, including the elevator machine room and lightning rod, was mounted on 24th of August 1970.

The next step was to install all the booms at 20 m interval from 20 upto 200 m. The booms can be swivelled upwards hydraulically for installation and maintenance of the instruments to be mounted at the end of the booms. The booms extend 9.4 m from the outer surface of the mast and are pointing in 10°, 130° and 250° resp. End of October 1970 the installation of the booms and a small 2-persons elevator inside the mast was completed.

(Source: T.S. Andringa, "De 200 m-mast te Cabauw ten behoeve van het K.N.M.I", see "articles")