Cracking ice

As Eissprengen refers to the blasting of ice , to hazards that are caused directly or indirectly through the ice to reduce or eliminate. A special course must be completed in Germany for the “ice sprinkling” qualification.

Types of exposure

After periods of severe frost, the ice layer on standing or flowing water can reach a thickness of several decimeters. As a result, strong pressure from the ice can be exerted on hydraulic structures (e.g. locks, weirs, bridges) but also on frozen ships, which can then cause damage to the walls, some of which can even be irreparable.

Ice drift is the floating of drift ice on water. Especially during the snowmelt, but also due to shipping, drift ice can accumulate on obstacles in the water ( ice rush ) and damage buildings. In extreme cases, the ice rush can even overflow its banks and cause damage to the ice floes far inland.

The formation of ground ice on the bottom of the water, possibly supported by ice drift or ice rush on the surface of the water, can lead to the formation of floods during the frost period. Serious damage to buildings and infrastructure can also occur here.

Types of explosions

Is often used as explosives gelatinous explosives or detonating cord used because they are usually sufficiently waterproof.

Throwing Charge

Pent-up ice floes can usually be loosened and set in motion again with thrown charges, i.e. packages made of explosives, which are provided with a safety fuse and thrown into the ice floes after ignition. This type of detonation is quick and easy, but has the disadvantage that the explosive charge can often not be placed precisely and is therefore usually too inefficient.

Placed cargo

If it is possible to remove the explosive charge from a structure, e.g. B. a bridge, or a boat with a rope or a pole, this method should be preferred, because this way the cargo can be placed in or even under the pile and its energy can develop most effectively.

Load brought in

If the ice cover is accessible, the explosive charges can be introduced directly under the ice surface. By precisely positioning the explosive charges, it is possible to break open and loosen the surface of the ice and thus reduce the ice pressure on buildings and to detach the ground ice by means of explosive charges using deeply inserted explosive charges. The detonating cord can be inserted directly into the slits made in the ice and thus develop the detonating effect in a finely dosed manner. With this method, however, the risk to the blasting personnel increases as the preparations for the blast have to take place on the ice surface.

application

With the increase in the performance of construction machines, they are sometimes also used to remove ice drift. In addition, hydraulic engineering measures and climatic changes mean that, on the one hand, ice drift is increasingly rare and, on the other hand, hydraulic structures are increasingly protected, e.g. B. by building icebreakers .

swell

1. ^ Federal Institute for Hydraulic Engineering (ed.): Ice drift near Passau / Inn . 1955.
2. ^ Ice drift near Passau / Inn  in the German Digital Library
3. ↑ Basic study - ice chipping problem at Krems and Thaya - abridged version ( Memento of the original from June 28, 2013 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. October 28, 2011 Retrieved January 5, 2012. 

literature

• Civil protection regulations 250 (KatS-DV 250) . Bonn 1984.
• Horst Roschlau: Sprengen - theory and practice . German publishing house for basic industry, Leipzig 1993, ISBN 3-342-00492-4 .