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Annex 3 
Use of the observation method according to EC 7 and DIN 1054 
The observation method in accordance with EC 7 is provided in DIN 1054 F181 as a method for certifying 
stability against collapse. It is a combination of the normal investigations and certifications (forecasts) 
with ongoing measuring checks of the structure, in which critical situations are controlled by using suita 
ble prepared technical measures. This method represents the recognised state of the art for structures 
whose foundation design is not based on secure engineering experience. The observation period for 
offshore wind turbines shall be extended to the operating phase. Boundary conditions that can neither 
be calculated with sufficient accuracy nor recognised in good time through observation shall be avoided 
by conducting work on the safe side and through design measures. Where possible, computer forecasts 
shall be supplemented by experience in comparable construction measures. The following preparations 
shall be made prior to the start of construction in order to use the observation method: 
• The limits of structural and ground behaviour to be maintained shall be defined. 
• The area in which the structural behaviour will probably take place shall be ascertained based on 
existing survey results. 
• It shall be demonstrated that the structural behaviour shall stay within the limits to be maintained, 
with an adequate degree of probability. 
• A measuring programme shall be prepared using significant parameters to check whether the actu 
al structural behaviour is within the limits that are to be maintained. 
• A plan of suitable countermeasures shall be developed for every possible eventuality in which mea 
surements indicate that limits to be maintained have been exceeded; this plan forms part of the 
certificate of stability against collapse. It shall be possible for the planned countermeasures to be 
taken at any time. 
• The measuring intervals and measurement results shall be capable of indicating the need for coun 
termeasures at a sufficiently early stage for the countermeasures to be taken in good time. 
• During construction work and operation, the measurement programme and its timely evaluation 
shall be carried out as scheduled and shall be documented. Deviations from the plan shall be docu 
mented.