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002045

Dipl.-Ing. (FH) Richard Haase

2026-04-30

Punching Shear Design with Double Headed Anchors According to EOTA TR 060 for EC 2

This article deals with double-headed stud shear reinforcement according to the European Technical Guideline EOTA TR 060, which can be used for design according to EC 2. In the following, the applicability, the consideration of manufacturer-specific parameters, and a breakdown of the required verification formats are described.

1 - Consideration of Manufacturer-Dependent Parameters

In RFEM 6, the technical guideline EOTA TR 060 [1] is implemented in such a way that the product-specific parameters can be adjusted individually. The different characteristic values of the manufacturer approvals (ETA) can be found in the capacity configurations under the standard parameters.

The following parameters may differ:

γ_s – partial safety factor for headed studs
k_pu,sl – factor for calculating V_Rd,max for slabs
η (k₁,k₂) – consideration of effective static depth for slabs
k_pu,fo – factor for calculating V_Rd,max for foundations

Standard Parameters for Punching Reinforcement According to EOTA TR 060

Info

It is planned to also enable consideration of the normal compressive stresses for the calculation of the v_Rd,max value for slabs. This positive effect of consideration must be explicitly mentioned in the corresponding ETA approvals or by the manufacturer. If this prerequisite is met, an option can be activated in the capacity configurations.

2 - Concrete Resistance Values

Slabs

The v_Rd,c calculation for slabs without shear reinforcement is equivalent to the calculation from EC 2 according to Equation 6.47. In [1], this equation is referred to as 2.10.

v_{Rd,c} = C_{Rd,c} \cdot k \cdot \sqrt[3]{100 \cdot ρ_{l} \cdot f_{ck}} + k_{1} \cdot σ_{cp} \geq (v_{\min} + k_{1} \cdot σ_{cp})

Punching Shear Resistance for Slabs Without Punching Shear Reinforcement According to Eq. 2.10

For the calculation of the maximum resistance value v_Rd,max, the normal compressive stresses are neglected as the default setting (as recommended in [1]). However, as also mentioned in Chapter 1, they can be taken into account by activating them in the capacity configuration.

The resistance value of the maximum applicable punching load is calculated according to Equation 2.17.

v_{Rd,max} = k_{pu,sl} \cdot v_{Rd,c}

Maximum Punching Shear Resistance for Slabs According to Eq. 2.17

Foundations

For the calculation of the resistance value for foundation design, the preliminary value C_Rd,c is assumed to be 0.18/γc (raft slab and slender foundations). The distance a is determined iteratively and results in the governing utilization of v_Ed,red/v_Rd,c. The upper limit here is 2d. A detailed explanation can be found in the following technical article:

https://www.dlubal.com/de/support-und-schulungen/support/knowledge-base/001409

v_{Rd,c} = C_{Rd,c} \cdot k \cdot \sqrt[3]{100 \cdot ρ l \cdot f_{ck}} \cdot \frac{2 \cdot d}{a} \geq \frac{v_{\min} \cdot 2 \cdot d}{a}

Punching Shear Resistance for Foundations Without Punching Reinforcement According to Eq. 2.16

The resistance value v_Rd,max is calculated according to Equation 2.19.

v_{Rd,max} = k_{pu, f o} \cdot v_{Rd,c}

Maximum Punching Shear Resistance for Foundations According to Eq. 2.19

3 - Applicability Limits of Punching Shear Reinforcement

The punching shear failure mode cannot be prevented in principle by arbitrarily high punching shear reinforcement. The verification of the maximum resistance v_Ed ≤ v_Rd,max must be satisfied as a prerequisite. Only then can the punching shear verification also be performed by means of a corresponding selection of punching shear reinforcement.

The factors k_pu,sl and k_pu,fo mentioned in Chapter 1 therefore have a major influence. The concrete resistance value v_Rd,c is multiplied by the corresponding factor depending on the member type. Higher factors therefore allow a larger applicable punching load.

Tip

If the verification "UL0401" is not satisfied, there is the possibility of increasing the area reinforcement: The mean flexural reinforcement ratio ρ_l influences the calculation of the resistance value v_Rd,c. However, the reinforcement ratio is limited to an application limit min (2%; 0.5 * f_cd / f_yd). If this is not sufficient either, only an increase in the concrete compressive strength or a larger effective static depth d remains.

4 - Resistance Values of Headed Studs

Unlike in the Eurocode, the reinforcement value of headed studs is not calculated per control perimeter. The guideline [1] distinguishes between two zones (see images for spacing rules).

Zone C is the area located 1.125d away from the column edge, the wall end, or the wall corner for slabs and 0.8d for foundations. All cross-sectional areas of the headed stud shanks in Zone C are added together to give the available reinforcement value. For slab design, there is also an η factor that takes the effective static depth into account.

Zone D is located between the outer control perimeter and Zone C.

V_{R d, s y} = n_{c} \cdot m_{c} \cdot \frac{{d^{2}}_{A} \cdot π \cdot f_{yk}}{4 \cdot γ_{s} \cdot η}

Double-Headed Anchor Resistance for Plates According to Eq. 2.18

V_{R d, s} = f_{ywd} \cdot A_{sw; 0.8d}

Double-Headed Anchor Resistance for Foundations and Slabs According to Eq. 2.20

5 - Outer Control Perimeter

The outer control perimeter is located at a distance of 1.5d from the last control perimeter reinforced with headed studs. The verification is satisfied if the acting force at the outer control perimeter no longer requires any punching shear reinforcement, i.e. if the concrete resistance is sufficient. This verification is carried out by comparing the required and available perimeter of the outer control perimeter.

u_{out,erf} = \frac{β_{red} \cdot V_{E d}}{v_{R d, c} \cdot d}

Required Circumference of Outer Perimeter Section According to Eq. 2.21

6 - Design Rules

Slabs

The following applies for radial spacing:

The first control perimeter must be arranged between 0.35d and 0.5d (from the edge of the punching shear control perimeter).
The second control perimeter may be located at a maximum of 1.125d (from the edge of the punching shear control perimeter); this is the boundary line of Zone C.
The subsequent control perimeters may not exceed a radial spacing of 0.75d to the previous control perimeter.

The following applies for tangential spacing:

Up to a radial spacing of 1.0d (from the edge of the punching shear control perimeter), the tangential spacing must be less than or equal to 1.7d.
On the boundary line of Zone C at 1.125d (from the edge of the punching shear control perimeter), the tangential spacing must be less than or equal to 1.8d.
In Zone D, the tangential spacing must be less than or equal to 3.5d.

Spacing Requirements for Double-Headed Anchors According to EOTA TR 060 for Plates

Isolated Footings and Raft Foundations

The following applies for radial spacing:

The first control perimeter must be arranged at 0.3d (from the edge of the punching shear control perimeter).
The second control perimeter may be located at a maximum of 0.8d (from the edge of the punching shear control perimeter); this is the boundary line of Zone C.
The subsequent control perimeters may not exceed a radial spacing of 0.5d to 0.75d (depending on the footing type) to the previous control perimeter.

The following applies for tangential spacing:

On the boundary line of Zone C at 0.8d (from the edge of the punching shear control perimeter), the tangential spacing must be less than or equal to 1.5d.
In Zone D, the tangential spacing must be less than or equal to 2.0d.

Spacing requirements for double-headed anchors according to EOTA TR 060 for Foundations

7 - Verifications

In order for the punching shear verification to be satisfied, four conditions must be met.

As mentioned in Chapter 3, the V_Rd,max verification must be satisfied so that the punching shear verification can generally be carried out. k_ETA are the manufacturer-specific values in this case. They differ for slabs (k_pu,sl) and for foundations or raft foundations (k_pu,fo).

V_Ed ≤ k_ETA ⋅ V_Rd,c

If the acting force V_Ed ≤ V_Rd,c (in the critical control perimeter), no punching shear reinforcement is required and the verification is satisfied. If V_Ed ≥ V_Rd,c, the punching shear reinforcement must be increased until the resistance value V_Rd,s ≥ V_Ed.

V_Ed ≤ max (V_Rd,c ; V_Rd,s)

The outer control perimeter is located at a distance of 1.5d from the last control perimeter installed with headed studs. The available perimeter of this outer control perimeter must be greater than or equal to the required perimeter.

u_out,erf ≤ u_out,vorh

Furthermore, the constructive installation rules must be observed and the following conditions fulfilled:

At least two control perimeters in Zone C
Radial spacings between the control perimeters
Tangential spacings between the headed studs on a control perimeter

Author

Richard works in Product Engineering, specializing in reinforced concrete, and also assists with Customer Support. He applies his expertise to develop practical solutions.

Links

Download Link for EOTA TR 060

References

https://www.eota.eu/sites/default/files/uploads/Technical%20reports/eota-tr-060.pdf

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