Reinforcement cover
This window contains inputs for the calculation of minimum cover in accordance with EN 1992-1-1, chapter 4.4.1.
Environment
The window shows exposure class specified in the window "Materials", as this input has an impact on the calculation of minimum cover. The exposure class can be change in the window "Environment" that can be launched by the button "Edit".
Structure class
The structure class is used for the determination of the value cmin,dur (minimum cover due to environmental conditions). Recommended class for the structures with design working life 50 years is S4. This class may be increased or reduced according to the rules given in the table 4.3N. The class shall be increased for design working life 80 or 100 years, reduction is possible for slabs or for members with special quality control of th production. The determination of the value cmin,dur is done in accordance with table 4.4N of EN 1992-1-1.
Other influences
This part contains parameters that affects minimal cover cmin and allowance in design for deviation Δcdev.
The minimum cover of elements exposed to abrasion should be increased by sacrificial layer in accordance with 4.4.1.2.(13). The "Abrasion class" has to be specified in this case. Available options are:
No abrasion | - The surface isn't exposed to abrasion, the minimum cover isn't increased
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XM1 - moderate abrasion | - The surfaces with moderate abrasion (e.g. members of industrial sites frequented by vehicles with air tyres) should be increased by k1. Recommended value is 5mm.
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XM2 - heavy abrasion | - The surfaces with heavy abrasion (e.g. members of industrial sites frequented by fork lifts with air or solid rubber tyres) should be increased by k2. Recommended value is 10mm.
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XM3 - extreme abrasion | - The surfaces with extreme abrasion (e.g. members industrial sites frequented by fork lifts with elastomer or steel tyres or track vehicles) should be increased by k3. Recommended value is 15mm.
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The window contains also following settings:
Max accregate diameter is greater than 32mm | - The minimum cover due to bond requirement cmin,b should be increased by 5mm if the nominal maximum aggregate size is greater than 32mm in accordance with 4.4.1.2.(3) of EN 1992-1-1.
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Uneven surface | - The minimum cover should be increased by at least 5mm for uneven surfaces (e.g. exposed aggregate) in accordance with 4.4.1.2.(11) of EN 1992-1-1.
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The additive safety element | - The concrete cover should be increased by the additive safety element Δcdur,γ in accordance with 4.4.1.2.(6). Recommended value is 0mm.
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Stainless steel | - The minimum cover may be reduced by Δcdur,st according to 4.4.1.2.(7) in cases where stainless steel is used or where other special measures have been. Recommended value of Δcdur,st is 0mm.
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Additional protection | - The minimum cover may be reduced by Δcdur,add for concrete with additional protection (e.g. coating) in accordance with 4.4.1.2.(8) of EN 1992-1-1. Recommended value is 0mm.
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Allowance in design for deviation | - The minimum cover shall be increased in design to allow for the deviation Δcdev in accordance with 4.4.1.3(1). Recommended value is 10mm. This value may be reduced for fabrication with a quality assurance system (includes measurements of the concrete cover). Permissible value should be within the interval <10mm, 5mm>. The allowance Δcdev may be reduced to <10mm, 0mm> for quality assurance system with very accurate measurement device and with rejection of non conforming members (e.g. precast elements).
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The minimum cover should be increased for concrete cast against uneven surfaces in accordance with 4.4.1.3(4). These options are available:
Concrete cast against prepared ground | - The minimum cover should be at least k1 for concrete cast against prepared ground (including blinding). The value of k1 should be considered as 40mm.
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Concrete cast against soil | - The minimum cover should be at least k2 for concrete cast against soil. The value of k2 should be considered as 75mm.
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Calculation can be checked in the bottom part of the window. Procedures are described in the chapter "Minimum cover".
Window "Reinforcement cover"
