Inspection of protections

Inspection of dynamic protection barriers against falling rock blocks, alluvium (torrential flows) and avalanches, inspection of slope stabilization meshes and inspection of galleries and protection dikes against rock falls, in accordance with the ONR24810 standard. Drafting of inspection and maintenance plan and repair proposals for its future functionality.

The maintenance of protection structures against the fall of rock blocks, alluvium and avalanches must follow a maintenance strategy that defines the moment and the extension of the control measures. The maintenance strategy is governed by the requirements for safety and effectiveness of protection, the number of protective structures, the category of structures, and the financial resources available.

The inspection does not include activities that lead to the conservation, modification or improvement of the state of a structure (or part of it); therefore not sufficient to maintain functionality - should wear and tear be discovered. The inspection serves to ensure the effectiveness (load security, practical utility, permanent stability) and the operational safety of a structure.

To the Prepare the state record, the current state of the structure is inspected. This includes the observation of the location, the function, the geometric measurements, the materials used and their characteristics, as well as the static system.

When preparing the state record, the recorded data is evaluated, qualified and analyzed, this is done based on the record and qualification of the current state, as well as based on a forecast about the future evolution of the state of the structure and the consequences for the established shelf life.

The following maintenance strategies are feasible for protective structures:

Foresight Strategy and Maintenance

The minor and previously determined measures are carried out by means of the maintenance regulations (internal regulations of the supply company). The material wear reserve according to DIN 31051 may not be fully utilized.

Preventive strategy due to status

Maintenance measures are established depending on the state. This presupposes the constant monitoring of the state of the protection structures.

Corrective strategy in the medium/long term

Maintenance measures are established when a critical state for the functionality of the structures is reached. The wear reserve is fully utilized.

Short-term corrective strategy

The measures are established when there is a danger of immediate loss of functionality or failure of the structure (wear reserve limit value exceeded). This strategy can lead to an irreversible loss of functionality. Neglected maintenance usually leads to the same result.

The anticipatory, preventive strategy due to the state, or corrective in the medium or long term, is admitted for all protective structures when this is in accordance with the determining security requirements. The short-term corrective strategy is only admitted in exceptional cases, if by means of it the protective effect is not reduced.

status levels

The structures should be organized by status levels, as cited in the following table. The lower the health level of a protective structure, the better its state of health.

Consequently, the maintenance/repair measures and the urgency of action can be deduced from the status levels.

The condition qualification must consider the condition at the time of data recording, a forecast on the evolution of stability and functionality depending on the useful life and the events that impact the structure.