LGA Institut für Umweltgeologie und Altlasten GmbH

Rockfall protection fence and then what? About the need for regular construction inspections

Posted on 20 April 2023.

High demands are placed on safety constructions (SiBW) against falling rocks and boulders with regard to structural safety, serviceability and durability. It is often forgotten that the construction of rockfall protection fences, meshes, rock nails, shotcrete and the like does not per se provide protection for decades. To reliably fulfill their function, regular inspection and, if necessary, maintenance (servicing) and repair (overhaul) of the SiBW are required.

For inspections, a distinction is made between initial recording, visual inspection, checking, testing and special checking. During the initial recording, the structure is inspected and all data relevant to the construction are recorded on a form. The annual visual inspection is used to check for any events that may have occurred and/or major damage (possibly affecting the serviceability of the SiBW). The visual inspection also serves to check the SiBW for vegetation that would hinder a reliable inspection of the construction in the following year, so that an clearing can be arranged in good time. If, in the opinion of the expert, the serviceability of the SiBW is impaired or an incident is reported, a special check of the SiBW is recommended. The regular inspection in the 5-year cycle replaces the visual inspection in the corresponding year and includes a manual inspection specific to the construction. The inspection in the 15-year cycle replaces visual inspection or checking in the corresponding year. Like the checking, the testing is carried out close to the hand and specific to the construction. In addition, the environment of the SiBW is checked for relevant changes to ensure the continued suitability and serviceability of the SiBW.

Inspection at an old safety construction

The inspections of the past months show the usefulness and necessity of initial recordings and periodical inspections. This year again, numerous “minor” defects were found, ranging from incorrectly installed wire rope clamps and missing components to incompletely filled boreholes with exposed anchors, thus negatively affecting the serviceability of the SiBW. As far as the defects are not due to external influence (missing component, theft, vandalism), experience has shown that they are usually remedied by the construction company at no cost, especially if the defect is claimed within the warranty period.

Exposed anchor

Other defects, in turn, included severe corrosion on constructions as well as uninspected self-built constructions on rock sections above residential buildings that are at risk of falling. Here, the defects cannot be remedied with simple steps, but the inspection should still not be avoided. After all, the inspection of the condition of a SiBW is closely linked to the question of insurance and liability in the event of personal injury and property damage.

Old metal cramps and rock nails, checking via rappelling

Feel free to contact us when:

• There are SiBW of unknown age and origin on your parcels of land
• You are a SiBW owner and have not had any inspections carried out yet
• You do not know for sure what condition your SiBW is in
• You wish to ensure that any claims for defects can be asserted before the expiry of the warranty period (in the case of buildings in accordance with VOB/B §13 Para. 4 four years after acceptance of the building)
• You want a tabular record and spatial location of your SiBW
• You wish to have an inspection plan for your SiBW for your long term planning
• You wish to be advised in any other way on SiBW and inspections