Slackline with COEUR PULSE and COEUR BOLT anchors - Petzl Netherlands
Search

Slackline with COEUR PULSE and COEUR BOLT anchors

The tension and bouncing on a slackline generates high cyclic loads that can exceed those found in climbing and other activities that the anchors were designed for.

Warnings

  • Read the technical notice before viewing the following techniques.
  • It is important to fully understand the information provided in the technical notice before using this complementary information
  • Mastering these techniques requires training.
  • Consult a professional before attempting to perform these techniques on your own.

The importance of proper installation for slackline anchors

Among our expansion anchors, only COEUR PULSE and COEUR BOLT 12 mm are recommended by Petzl for slacklining.

Direction of pull: place the bolts perpendicular to the load

Tests show that COEUR PULSE and COEUR BOLT do not hold up well under repeated axial loading.

Tests show that COEUR PULSE and COEUR BOLT do not hold up well under repeated axial loading.
Tests show that COEUR PULSE and COEUR BOLT do not hold up well under repeated axial loading.

Load-sharing: increasing the number of anchors is insufficient

The installation must allow each anchor to share an equal part of the load. If one anchor is loaded more than the others and fails, the shock load on the other anchors can cause them to fail as well. There are many techniques for load-sharing between anchors, the basic rule being the more acute the angle, the better the load-sharing. The more anchors there are, the more complex the installation.

WARNING: to effectively share the load between the anchors, the focal point must be mobile OR the direction of pull perfectly defined and taken into account during installation.

The installation must allow each anchor to share an equal part of the load.
The installation must allow each anchor to share an equal part of the load.

Insufficient strength of PULSE anchors and caving anchors

The maximum strength of PULSE and caving anchors, tested in high-quality concrete during certification, might seem sufficient for slacklining if the direction of pull is perfectly oriented. However, the risk of a pull in the wrong direction is significant; therefore Petzl recommends that these anchors not be used for slacklining or for any other similar activity.

Insufficient strength of PULSE anchors and caving anchors
Insufficient strength of PULSE anchors and caving anchors
Insufficient strength of PULSE anchors and caving anchors

Strength testing of anchors

An anchor is designed to support a static load and/or an occasional dynamic load (fall). Cyclic dynamic loading is inherent in slacklining.

Anchor fatigue resistance

A characteristic of slacklining is that the highly tensioned webbing transmits cyclic loads to the anchors (vibration, bouncing, falls). The load sustained by the anchor is not only the initial tension in the webbing: the use of the line increases this tension.

The frequency and the force applied to the anchors depends on many parameters: initial tension, line length, type of displacement, number of falls, number of anchors and efficacy of load-sharing...

Laboratory test of anchor fatigue resistance:

A load value of 5 kN was chosen for the tests; this corresponds to a 10 to 12 kN load on the slackline which would be roughly shared between three anchors.

The test consists of a succession of loads at the chosen value, then unloading, at a frequency of 1 Hz. The number of cycles before break is measured.

Anchor fatigue resistance.
Anchor fatigue resistance.

Static strength of COEUR PULSE and COEUR BOLT anchors

The maximum strength of COEUR PULSE and COEUR BOLT anchors, tested in high quality concrete during certification, is hypothetically sufficient for slackline use.

Note 1: any incorrect installation or installation in poor-quality rock or concrete can reduce anchor strength; see the Instructions for Use for COEUR PULSE and COEUR BOLT.

Note 2: the maximum strength value does not take into account any non-destructive deformation of the anchors, which can occur at significantly lower values.

Static strength of COEUR PULSE anchors.
Static strength of COEUR BOLT anchors.
Static strength of COEUR BOLT anchors.