In the following calculation a combination of Eurocode 2 and Eurocode 7 has been used. Design yield strength. Young modulus. Poisson coefficient.

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1 In the following calculation a combination of Eurocode and Eurocode 7 has been used. Materials Partial safety factors EN : γ c 1.5 γ s 1.15 Partial safety factor for concrete. Partial safety factor for steel. Concrete: C30/37: f ck 30MPa Characteristic compressive strenght. f cd f ck γ c Design compressive strenght. E cm 33GPa ρ Rc 500 kg m 3 Mean young modulus for concrete. Mass density for reinforced concrete. Reinforcement: Ribbed bar B500S f yk 500MPa Characteristic yield strength. f yd f yk γ s Design yield strength. E s 10000MPa ν 0.3 ρ s 7850 kg m 3 Young modulus. Poisson coefficient. Mass density. Moraine soil: Reference [31] σ b 1600kPa θ d 34deg c u 0kPa Dimensions: Tower: R tower 3.875m Bearing capacity of the soil. Friction angle of the soil. Undrained shear strength Base outer radius of the tower. F -

2 Slab: b 14m l 14m h slab m Length of the slab. Width of the slab. Height of the slab. ϕ 5mm ϕ' 1mm Diameter of the reinforcement in the main direction.. Diameter of the reinforcement in the secondary direction. ϕ s 15mm ϕ' Diameter of the shear reinforcement. Concrete cover: The concrete cover c nom is the distance between the surface of the reinforcement closest to the nearest concrete surface EN (4.4.1). c nom c min Δc dev EN (4.1) c min : Minimum distance satisfaying the requirements for both bond and environmental conditions for a service life of 50 years. EN c min.b ϕ Minimum cover due to bond requirement EN (3) c min.dur Δc dur.γ 30mm Minimum cover due to environmental conditions EN (5) 0mm Additive safety element EN (6) Δc dur.st 0mm Reduction of minimum cover for use of stainless steel EN (7) Δc dur.add 0mm Reduction of minimim cover for use of additional protection EN (8) 30 mm c min max c min.b c min.dur Δc dur.γ Δc dur.st Δc dur.add 10mm Δc dev : Increase of the required minimum cover by the accepted negative deviation EN Δc dev 10mm c cov c min Δc dev 40 mm c lat 70mm Concrete cover in the base and the top of the slab. Lateral concrete cover of the slab. Depth to bottom reinforcement, placed in tow directions and two layers: d 1 h slab c cov ϕ s d h slab c cov ϕ s 0.5ϕ 1.5ϕ mm mm Depth to he first reinforcement layer. Depth to he second reinforcement layer. d 1 d d m 190 mm Average dept to the bottom reinforcement. F - 3

3 Depth to top reinforcement, placed in tow directions and two layers: d' 1 c cov ϕ s d' c cov ϕ s 0.5ϕ' 1.5ϕ' 61 mm 73 mm Depth to he first reinforcement layer. Depth to he second reinforcement layer. d' 1 d' d' m 67 mm Average dept to the bottom reinforcement. Loads applied to the slab See appendix F1 All the forces applied to the wind trubine are transferred to the foundation base as: Vertical force V. Overtunrning moment M. Horitzontal force H. H 1000kN V 777kN M 11076kNm M e m Eccentricity of the slab. Reference [15]. V b eff b e l eff l 14m 6.03 m Effective width of the equivalent rectangular foundation.reference [15]. Effective length of the equivalent rectangular foundation.reference [15]. A eff b eff l eff 84.39m Effective area of the equivalent rectangular foundation. σ soil V A eff 39.33kPa Compressive stress applied to the soil. l cantilever l R tower 3.15 m Length of the cantilever equivalent to the slab. Load per unit length because of the reaction of the soil: g soil σ soil b eff 1m l cantilever kn m Load per unit length because of the weight of the slab: f slab h slab 1mρ Rc g kn m Moment that needs to be resisted by the top reinforcement: 1 M top f slabl cantilever 39.4kNm F - 4

4 Moment that needs to be resisted by the bottom reinforcement: 1 M bottom g soill cantilever M top F - Design of foundations for the prestressed concrete tower kNm Load that needs to be resisted by the shear reinforcement: kN V shear max f slab l cantilever f slab l cantilever g soil l cantilever Limit states verification Bearing resistance failure: EN σ b σ soil 1600kPa 39.33kPa Design bearing resistance of the soil. Ultimate limit state stress normal to the foundation. Verification 1 σ b σ soil 1 Failure by sliding: EN H 1000kN S d Vtan θ d kn Horitzontal component of the design load. Design shear resistance between the base of the foundation and the ground. For the safety against failure by sliding on a horitzontal base, the following inequality shall be satisfied: Verification H S d 1 In addition, according to [15] the following expression must also be fulfilled: Verification 3 H V Failure by overturning: [15] γ d 1.5 Partial safety factor for the overturning moment. Verificaiton 4 V l M γ d 1 Reinforcement Bottom reinforcement: A s M bottom f yd d m d' m mm Bottom reinforcement amount per unit width. F - 5

5 A s.total A s l mm Total required bottom reinforcement. n bar ceil A s.total π ϕ 4 10 Number of reinforcing bars required. b c lat n bar ϕ s f n bar cm Spacing bars. 400 mm s max min 3h slab 400mm Maximum distance between bars in the main direction. EN s f s max 1 Top reinforcement: A' s M top f yd d m d' m mm Bending top reinforcement amount per unit width. A' s.total A' s l mm Total required top reinforcement. n' bar ceil A' s.total π ϕ' 4 37 Number of reinforcing bars required. b c lat n' bar ϕ' s' f n' bar cm Spacing bars. 450 mm s' max min 3.5h slab 450mm Maximum distance between bars in the secondary direction. EN s' f s' max 1 Shearing reinforcement: Calculation of the reinforced bars required to support the shearing force V R. Desing shear resistance of the cantilever without shear reinforcementty V Rd.C :EN (6..a) 3 V Rd.c C Rd.c K 100ρ fck 1000d 0.18 C Rd.c γ c 0.m K d m Recommended factor by EC-. Factor to consider the grainy effect of the aggregate. F - 6

6 ρ A s d m 1m 0.00 Mechanical volume of the section. f ck 30 MPa Characteristic yield strenght of concrete. 3 V Rd.c C Rd.c K 100ρ fck d m 1000mm kn V Rd.c V shear 0 Concrete cannot support the shear force. As a concequence, shearing reinforcement is needed. V Rd.shear A s.shear f yd z s shear cot( θ) Desing shear force which can be sustained by the yielding shear reinforcement. ϕ s A s.shear π mm z d m d' m f yd MPa mm Mechanical contribution of the stirrups. Inner lever arm of the cross-section. Characteristic yield strenght of steel. θ 45deg s shear 1cm Angle between concrete compression struts and the main tension chord. Spacing of the stirrups. V R.shear A s.shear f yd z s shear cot( θ) kN V R.shear V shear 1 Number of stirrups needed: b 14m Length of the slab. n s 103 Number of stirrups used. b c lat n s ϕ s n s 1s shear 1 F - 7