Anchor (climbing)

When mountain climbing and sport climbing is meant by fixed point ( also savepoint ) a reliable attachment point at which a sling, a Expressset or a snap hook can be fitted to protect. Fixed points are required for belays and for the establishment of stands. In state courts as well as abseiling particularly reliable anchor points are required, since a failure would have particularly serious consequences. In these cases, the backup is usually the simultaneous use of multiple (redundant ) fixed points.

With many established routes in the rock was preparing fixed points found in the form of bolts. Often fixed points but must be attached by the climbers themselves, using the appropriate material. Such fixed points will be set as a rule, from the pre- doughs ends and removed from Nachsteigenden.

Fixed points at Rock Climbing

Proof mounting points

Fixed savepoints are permanently attached to the rock (often from the catalogers of the route ) and remain there. That's why they are as weatherproof.

" Glued " bolts are currently the most reliable security device. The " bonding " refers to the use of cement, sand and water. Special adhesive hooks, called Buhler hook and AV safety hooks, it can also be used as a full stand, that is, it may be waived under certain circumstances the use of another fixed point. Redundancy through a second fixed point, however, is always recommended. When mounted in rock Buhler hook of the breaking load value is in a radial loading direction at 30 to 60 kN.

Widely used are also not glued bolts. This offer is not quite the safety of the adhesive hook, but belong - with some exceptions - the most reliable backup means. Normal hooks are wrapped itself in crevices of rock climbers and usually remain there. Already embarked hooks before use but still to be checked for strength. Today, mountaineers and climbers use hardly normal hook, these have been largely replaced by bolts or mobile securing means such as clamping devices and clamping wedges ( see below).

In modern sport climbing, the most routes with bolts at frequent intervals be hedged. The increased security is one of the main reasons why the Climbing has become a popular sport. In route descriptions and climbing guides fixed fixed points are given and plotted in graphical representations route, so-called topos, with symbols. Bolts are with a big " X" symbolizes, stands with a double major " XX" and normal hook with a small " p". The fixed points can be apart from 2 up to 50 meters, so to an entire cable length. Routes that have few or no fixed securing points for belays are called "Alpine protected ".

In general, well-worn hard routes are more secure than lighter. In routes with very high difficulty almost exclusively fixed securing points are possible because the compact rock structure often provides no opportunity for self- creation of additional fixed points. Width climbing routes where no securing points are present and no can be attached are referred to as "moral", because there the Climbing must enter into a high risk.

Self to be set up checkpoints

Here, a natural fixed points such as hourglasses, trees or rock outcrops are used to. Using a sling at the appropriate length in this case, a fixed point will be established where rock heads, this is called Köpfelschlinge.

In addition, today there are nodes slings, clamping wedges and terminal devices ( for example, Friends ) are common. The latter are referred to as active security agents, as they change shape under load and counteract this way a pull-out. How safe is a fixed point such produced depends on the rock structure, the material used and on the experience and the skills of the Anbringenden.

Chocks or Köpfelschlingen allowed only in one direction - to be charged, else the loop is stripped or pulled the wedge out of the crack - most usefully for Sturzzug down. If a belaying used to stand is to be subsequently used for securing the lead climber, when use of such fixed points is a remodeling of the stand needed ( guying down against Sturzzug up). Another way to provide a nearly full checkpoint, even when using this securing means is set up over one another two fixed points at a distance, wherein the lower and the upper top can be loaded down and to clamp together. However, it must be noted that no lateral forces may also occur in such a strain of the fixed points.

Fixed points in snow and ice

When setting up checkpoints in the ice is to assess the quality of the ice is crucial. In the solid ice ice screws are most often used for pitches is usually used two of them. In fine, this ice can be used " in series ", meaning that the second Eisscharaube will only be charged when the first one fails. In bad ice is used, the set triangle of forces, which distributes power equally to both ice screws. Another possibility in the ice to set up a fixed point represents a Eissanduhr

In snow or firn one uses a T armature as a fixed point, that is, a transversely to the direction buried in the snow elongated object such as an ice pick or backpack. Rare Firnanker be used elongated metal angles that are driven into the firn.

Compensation anchoring

To increase the security checkpoints are often set up with a double triangle of forces. For this purpose, two or more backup points with a tape loop are connected and hooked a central carbine. As a result:

• Load balancing: the load is distributed between two savepoints
• Redundancy: if a savepoint fails, the other keeps

Load balancing is crucial that the angle between the belt loops on the central carbine is as small as possible ( more pointed than an equilateral triangle).

For the redundancy is crucial that a strand of webbing sling is twisted hooking the carabiner central to an eye so that the carabiner still hangs in the sling after failure of a backup point.

Forces at checkpoint

The forces that act on a single backup point depend on the weight of the climber, the headroom on the fall factor, the elasticity of the rope, the friction losses in the dynamic security cable and in the intermediate backups and the friction between the rope and rock.

What forces occur directly in a fall in the state, is given in the adjacent table.