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Part B - Certificates and approval requirements 
• With regard to certifying the fatigue strength of reinforced concrete and reinforced concrete compo 
nents, refer to the DASt publication 439 „CEB-FIP Model Code 1990“ (Berlin 1994) f151. 
• With regard to the structural design of solid structures, refer to the current version of the Offshore 
Standard DNV-OS-C502 „Offshore concrete structures“ £16]. 
• With regard to the structural design of grouted joint connections, refer to the DNV publication „Struc 
tural Design of Grouted Connection in Offshore Steel Monopile Foundations“ (Global Windpower, 
2004) f 171 as well as the GL Guideline for the Certification of Offshore Wind Turbines [6], chapter 
5.4.4 „Grouted connections“. 
• With regard to certificates using the finite element method, refer to the GL Guideline for the Certifica 
tion of Offshore Wind Turbines [6], chapter 5.A „Strength Analysis with the Finite Element Method“. 
3.2.3.3 Required certificates 
• Certificates of dynamic properties: 
Natural frequencies of the overall system comprising turbine, tower and substructure including 
the foundation elements 
Testing compliance of natural frequencies in the load simulation with the natural frequencies 
calculated based on the support structure data 
Checking of vibration amplitudes and vibration speeds as well as accelerations with regard to 
the functions of the offshore wind turbine 
• Certificates in the ultimate limit state (ULS): 
Strength certificates 
Stability certificates 
Certificates of force applications and connections 
• Certificates in the fatigue limit state (FLS): 
Certificate against fatigue (operational stability) 
• Certificates in the serviceability limit state (SLS): 
Limitation of deformation 
Limitation of concrete compressive stresses, steel stresses and decompression 
Limitation of crack widths 
• Certificates of durability: 
Certificate of the corrosion protection concept: 
Cathodic corrosion protection with sacrificial anodes or by impressed-current systems and 
coatings 
• Certificates in the accidental limit state (ALS) if such are provided. 
• Evaluation of hull-retaining properties of the support structure: 
Estimate of the potential damage to a ship's hull on collision between unmanoeuvrable ships 
and support structures of the offshore wind turbine 
Evaluation of the positional security of the components of the offshore wind turbine (nacelle) 
under short-time effect of collision loads 
• Representation of the noise emissions from the support structure, in particular the substructure: 
Noise emissions during the construction phase and 
Noise emissions during the operation phase 
• Representation of the planned inspection of the support structure by a condition inspection system 
(CMS) for at least 1/10 of the offshore wind turbines