Traditional fascine mattresses
Handcrafted classic fascine mattresses
To protect riverbeds and riverbanks from erosion by the floating water, fascine mattresses were constructed already about 50 to 60 years ago. The classic fascine mattress are still made in that same traditional way, using only natural materials (brushwood). The classic fascine mattress is labor intensive to produce, due to the use of only natural materials. But this makes it also environmental friendlier than the modern fascine mattresses, in which (plastic) cloth is used.
Van Aalsburg has the knowledge of and experience in manufacturing and installing all types and sizes of fascine mattresses, used to protect riverbanks and riverbeds.
Producing the classic fascine mattress
The “zate” is the construction site - partly next to, and partly in the water - were the fascine mattresses are made. Because much brushwood has to be used, the construction site is accessible for the mobile crane.
Large plastic pipes - connected to ropes that will be used as draglines later on - will be placed at the construction site. Because of the huge weight and size of fascine mattresses, the pipes are usefull to help the mattresses slide easily into the water without any damage. Van Aalsburg has the experience and expertise to produce 3.000 m2 fascine mattresses a day.
First of all the framework of weips will be placed on the plastic pipes: every meter a weip for the first layer, followed by a second layer at right angles to the first one. Each intersection will be tied with rope which is also the rope to be used for further tying up brushwood into the mattress. The rope has a special sisal-polypropleen composition that will secure further, once it is in the wet condition.
When all weips are tied, the brushwood will be divided and spread into the framework to a thickness of 10 to 15 centimeters. A second layer of brushwood will be placed, at right angles to the first one. The customer decides about the number of layers and the thickness of weips and brushwood.
On top of the last brushwood layer, two layers of weips will be placed again, at right angles to each other. All the layers will be tied secure with the rope that was placed at the beginning of the production of the mattress. In this way, the whole mattress is firmly tied together, using special knots and the ancient technique that is still used by Van Aalsburg staff.
With the draglines that were earlier placed under the pipes and mattress, the construction will be dragged to the destination and will be sunk to protect the bottom of river- and canalbeds. In some cases the mattresses are sunk to a depth of 20 meters.
Weips - the compressed sausages of brushwood, machine wrapped with rope - are used in classic fascine mattresses. With harvesting the 2 to 4 years old brushwood during wintertime, the brushwood will be bundled instantly into 65 centimeter bundles. The brushwood will be transported to the Van Aalsburg plant, where the twigs will be squeezed and rope-wrapped by the weipmachine. Van Aalsburg can produce about 20 to 30 kilometers of weips a day.
The size of the weips comply to the needs of the various customers, in general weips have a 30 centimeters thickness and length varies from 1 to 20 meters. At Van Aalsburg all equipment is available to do the job, even to transport the weips with huge lengths, throughout Europe.