Execution Class

The Execution Class defines the allowable construction tolerances. In the absence of any particular client requirements, the Execution Class can be determined using the following procedure.

1. Determine the Consequences Class

For bridges, the UK National Annex to EN 1990:2002 Clause NA.3.2.1 recommends Consequence Class CC2.

Table B1 of EN 1990:2002+A1:2005 suggests the following Consequence Classes:

Consequences Class Description Examples of buildings and civil engineering works
CC3 High consequence for loss of human life, or economic, social or environmental consequences very great Grandstands, public buildings where consequences of failure are high (e.g. A concert hall)
CC2 Medium consequence for loss of human life, economic, social or environmental consequences considerable Residential and office buildings, public buildings where consequences of failure are medium (e.g. an office building)
CC1 Low consequence for loss of human life, and economic, social or environmental consequences small or negligible Agricultural buildings where people do not normally enter (e.g. Storage buildings), greenhouses

2. Determine the Service Category

EN 1090-2:2008+A1:2011 suggests the following descriptions for Service Categories

Service Category Description
SC1 Structures and components designed for quasi static actions only (Example: Buildings)
Structures and components with their connections designed for seismic actions in regions with low seismic activity and in Ductility Class DCL*
Structures and components designed for fatigue actions from cranes (class S0)**
SC2 Structures and components designed for fatigue actions according to EN 1993. (Examples: Road and railway bridges, cranes (class S1 to S9)**, structures susceptible to vibrations induced by wind, crowd or rotating machinery)
Structures and components with their connections designed for seismic actions in regions with medium or high seismic activity and in Ductility Class DCM* and DCH*

* DCL, DCM, DCH: ductility classes according to EN 1998-1

** For classification of fatigue actions from cranes, see EN 1991-3 and EN 13001-1

3. Determine the Production Category

Table B.2 of EN 1090-2:2008+A1:2011 suggests the following descriptions for Product Categories

Production Category Description
PC1 Non welded components manufactured from any steel grade products
Welded components manufactured from steel grade products below S355
PC2 Welded components manufactured from steel grade products from S355 and above
Components essential for structural integrity that are assembled by welding on construction site
Components with hot forming manufacturing or receiving thermic treatment during manufacturing
Components of CHS lattice girders requiring end profile cuts

4. Determine the Execution Class

Table B.3 of EN 1090-2:2008+A1:2011
Table B.3 of EN 1090-2:2008+A1:2011

Alternatively, 1700 Series of the UK Specification for Highway Works recommends Execution Class EXC3 for concrete bridges.