Factors Considered When Determining Execution Class
The procedure for determination and use of execution class according to EN 1090 – 2 considers that the design will be carried out in accordance with EN 1993 for steel structures or EN 1994 for steel parts of composite structures to achieve consistency between the assumptions made in the structural design and the requirements for execution of the work. The determination of execution classes is done in the design phase where specifics for design and execution of the structure are evaluated and the information on execution requirements are give in the execution specification.
A Consequence Class would consider the potential loss of life / injury, commercial or environmental issues relating to failure of a component and or structure
Intended use of the structure
Hazards may arise from the intended use of the structure, these can include service factors and production factors
Service factors arising from the actions to which the structure is likely to be exposed to during erection and use
Production factors arising from the complexity of the execution of the structure and its components
Service Category (intended Use)
Service category 1:
Structures and components designed for quasi static actions only
Structures and their components with their connections designed for seismic actions in regions with low seismic activity
Structures and their components designed for fatigue actions from cranes
Service category 2:
Structures and components designed for fatigue actions according to EN 1993, structures susceptible to vibrations
Structures and components with their connections designed for seismic actions in regions with medium or high seismic activity
Determination of Execution classes
The recommended procedure for determination of execution classes is:
1. Selection of consequence class
2. Selection of a service category
3. Determination of the execution class from the results of the operations 1 and 2.
The above is used to determine the execution class
Some structures may contain different execution classes for various parts of the building, for example a main stadium structure could be execution class 4 and some secondary steel work i.e. fire escapes may only be considered execution class 2.
Companies that are EN 1090 certified by a Notified Body can register here http://www.1090register.com