For centuries scaffolding has been used as a means to facilitate the construction process. Towers, bridges, churches, have all been erected using scaffolds.
In the past, calculation and design was aimed at the structure itself. A scaffold was merely a means to attain the goal. In the present era, the analysis of the scaffold as a ‘true’ structure has gained a huge importance.
One of the main reasons for this are the numerous accidents that occurred with scaffolding over time which in many cases were caused by faulty design.
Recently European standard EN 12811 has been published which gives guidelines on the safety and design of scaffolding structures. In addition, a specific standard EN 12810 was published concerning façade scaffolds.
In this paper first of all an overview is given of the method of analysis which is presented in these European standards. In a separate chapter the modelling and analysis of scaffolding structures within SCIA Engineer is outlined.
The method of analysis is then illustrated and verified by comparing the results of a SCIA Engineer analysis model to an actual laboratory test.
The final part of this paper details the SCIA Scaffolding design methodology which uses a single intelligent model for all phases of the working process. The advantages of this approach compared to the existing workflow are illustrated.
Complexity of Scaffolds
In many cases, scaffolds are designed using common linear analysis together with the effective length method. In this case the internal forces are derived from a linear 1st order analysis and the members are designed according to a relevant design code.
It has however been pointed out that this method of design is not reliable in case of scaffolding structures due to the following:
- Scaffolds contain a high degree of non-linearity.
- Scaffolds are prone to large deflections.