BS EN 61773:1997

This standard BS EN 61773:1997 Overhead lines. Testing of foundations for structures is classified in these ICS categories:

• 29.240.20 Power transmission and distribution lines

This International Standard is applicable to the testing procedures for foundations of overhead line structures. This standard distinguishes between:

1. foundations predominantly loaded by axial forces, either in uplift or compression, acting in the direction of the foundation central axis. This applies to foundations of rigid lattice towers with typical individual footings, that is concrete pad and chimney foundations, steel grillages, concrete piers, piles and grouted anchors. Guy (stay) foundations are included when they are tested in line with their true guy inclinations;

2. foundations predominantly loaded by lateral forces, overturning moments, or a combination of both. This applies to single poles with typical compact foundations, for example monoblock foundations, concrete slabs, concrete piers, piles and poles directly embedded in the ground. It may also apply to H-frame structure foundations for which the predominant loads are lateral forces, overturning moments, or a combination of both;

3. foundations loaded by a combination of forces mentioned under a) and b).

Tests on reduced scale or model foundations are not included. However, they may be useful for design purposes.

Dynamic foundation testing is excluded from the scope of this document.

The object of this standard is to provide procedures which apply to the investigation of the load-carrying capacity and/or the load response (deflection or rotation) of the total foundation as an interaction between the foundation and the surrounding soil and/or rock. The mechanical strength of the structural components is not within the object of this standard. However, in the case of grouted anchors, the failure of structural components, for example the bond between anchor rod and grout, may predominate.

This provides a procedure which apply to the investigation of the load carrying capacity and or the load response of the total foundation as an interaction between the foundation and the surrounding soil and/or rock.