Tower design
Wind turbine towers are structure subject to highly dynamic loads and require attention to the design of the details as well as a good understanding of the general dynamic behavior. The market is progressively driving down the cost of such structures, thus continuously demanding improvements and optimizations in the design and construction processes. A concrete tower design requires the verification of the structure as a whole as well as the verification of the connection joints along the shaft.
We use analytical as well as numerical methods and tools to calculate the internal forces in the tower and proceed with the necessary verification. The type of model used largely depends on the scope of the study:
- Design
- Optimization
- Assessment of existing structure
When required, large use of nonlinear analyses is performed in order to take into account of the material resources.
Tower behavior
Designing a wind turbine tower requires a deep knowledge of structural dynamics as well as mechanics of materials. Tower components/parts are always subject to dynamical actions that cause fatigue accumulation in the materials.
Therefore, linear static calculations are not always sufficient to perform the design of this highly wind sensitive structures. Furthermore, for concrete towers the transition from the intact state to the cracked state is of particular importance when it comes to the definition of the load structure.
Nonlinear concrete analyses are often used to asses the post-cracking behavior of the tower under extreme loads. The stiffness reduction must be carefully evaluated and discussed with the load team. Its impact on the structure response, durability and maintenance is of very high importance.
Numerical analysis
Hand made analytical calculation can be easily done for the structural design of a concrete tower. They give already good results for an economical shape of the structure. However, when improvements and cost-down is necessary, more attention to the details is needed. We use concrete nonlinear analysis exactly in order to fine tune the predictions obtained from hand made calculations. Different technical solution may be considered when analyzing service or ultimate load conditions and they influence each other. Sometimes, computationally expensive analyses must be made in order to obtain even small savings. Such analyses may become necessary also in the assessment phase of existing structure:
- Lifetime extension
- Structural upgrades
- Structural integrity/reliability assessment
We provide support for all design and assessment requirements and the selection of the type of investigation is always presented and discussed with the Customer based on the specific target.