Tekniska aspekter

1.1 Scope of prEN 1993-1-4 This document provides supplementary rules for the structural design of steel structures that extend and modify the application of EN 1993-1-1, EN 1993-1-3, EN 1993-1-5 and EN 1993-1-8 to austenitic, duplex (austenitic-ferritic) and ferritic stainless steels. NOTE 1 Austenitic-ferritic stainless steels are commonly known as duplex stainless steels. The term duplex stainless steel is used in this document. NOTE 2 Information on the durability of stainless steels is given in Annex A. NOTE 3 The execution of stainless steel structures is covered in EN 1090-2 and EN 1090-4. 1.2 Assumptions Unless specifically stated, EN 1990, EN 1991 (all parts), EN 1993-1-1, EN 1993-1-3, EN 1993-1-5 and EN 1993-1-8 apply. The design methods given in prEN 1993-1-4 are applicable if - the execution quality is as specified in EN 1090-2 and EN 1090-4, and - the construction materials and products used are as specified in EN 1993-1-1, EN 1993-1-3, EN 1993 1-5 and EN 1993-1-8, or in the relevant material and product specifications.

(1) EN 1993-1-10 contains design guidance for the selection of steel for fracture toughness and for through thickness properties of welded elements where there is a significant risk of lamellar tearing during fabrication. (2) Section 2 applies to steel grades S 235 to S 690. However section 3 applies to steel grades S 235 to S 460 only. (3) The rules and guidance given in section 2 and 3 assume that the construction will be executed in accordance with EN 1090.

1.1 Scope of prEN 1993-1-6 (1) prEN 1993-1-6 provides rules for the structural design of plated steel structures that have the form of a shell of revolution (axisymmetric shell). (2) This document is applicable to unstiffened fabricated axisymmetric shells formed from isotropic rolled plates using both algebraic and computational procedures, and to stiffened axisymmetric shells with different wall constructions using computational procedures. It also applies to associated circular or annular plates and to beam section rings and stringer stiffeners where they form part of the complete shell structure. The general computational procedures are applicable to all shell forms. (3) This document does not apply to manufactured shells or to shell panels or to elliptical shell forms, except that its computational procedures are applicable to all shell structures. This document does not apply to structures under seismic or other dynamic loading. It does not cover the aspects of leakage of stored liquids or solids. (4) Cylindrical and conical panels are not explicitly covered by this document. However, the provisions of subclause 9.8 can be used provided that appropriate boundary conditions are taken into account. (5) This document defines the characteristic and design values of the resistance of the structure. (6) This document is concerned with the requirements for design against the ultimate limit states of: - plastic failure; - cyclic plasticity; - buckling; - fatigue. (7) Overall equilibrium of the structure (sliding, uplifting, overturning) is not included in this document. Special considerations for specific applications are included in the relevant application parts of EN 1993. (8) Detailed formulae for the simple calculation of unstiffened cylinders, cones and spherical domes are given in the Annexes. (9) Provisions for simple calculations on specific stiffened shell types are given in EN 1993-4-1. (10) This document is intended for application to steel shell structures. Where no standard exists for shell structures made of other metals, including high strength steels, the provisions of this document are applicable provided the appropriate material properties of the metal are taken into account. (11) The provisions of this document are intended to be applied within the temperature ranges defined in the relevant EN 1993 application parts. (12) Where no application part defines a different range, this document applies to structures within the following limits: - design metal temperatures lie within the range −50 °C to +100 °C, except when using the special provisions given in 5.1; - radius to thickness ratios (r/t) within the range 50 to 2 000; - manufactured circular hollow sections according to EN 10210 and EN 10219 are outside the scope of this standard and are covered by EN 1993-1-1. However, if no other provisions are available, the rules of this document are useful for manufactured circular hollow sections. In particular, this document is applicable to the design of manufactured piles (see EN 1993-5) provided the imperfections and tolerance requirements of EN 1993-5 are adopted in place of those specified in prEN 1993-1-6, and where no other standard covers the specific pile geometry. NOTE 1 Experimental and theoretical data relating to manufactured circular hollow sections were not considered when this document was drafted. The application of this document to such structures therefore remains the responsibility of the user. NOTE 2 The stress design rules of this document can be rather conservative if applied to some geometries and loading conditions for relatively thick-walled shells. NOTE 3 Thinner shells than r/t = 2 000 can be treated using these provisions but the provisions have not been verified for such thin shells. ...

1.1 Scope of prEN 1993-1-7 (1) prEN 1993-1-7 provides rules for the structural design of assemblies of unstiffened and stiffened steel plates whose elements are under predominantly distributed transverse loads. (2) prEN 1993-1-7 is applicable to containment structures such as silos, tanks, digesters and lock gates, where the external actions chiefly act transversely on their individual plates or panels. Where a plate or panel under bending is additionally subject to membrane forces that have a significant effect on the resistance, this document covers assessment of the resistance through its computational analysis procedures. (3) prEN 1993-1-7 is applicable to structures with rectangular, trapezoidal or triangular component plate segments, each with one axis of symmetry. (4) prEN 1993-1-7 does not apply to plates or panels where the dominant structural resistance requirement relates to membrane forces in the plates (for these, see EN 1993-1-5). (5) prEN 1993-1-7 does not apply to plates or panels whose curvature (out of flatness) exceeds that defined in 1.1 (14). For such curved plates, see EN 1993-1-6. (6) prEN 1993-1-7 does not apply to circular or annular plates. For such plates, see EN 1993 1-6. (7) prEN 1993-1-7 does not apply to cold-formed sheeting. For such plates, see EN 1993-1-3. (8) This document is only concerned with the requirements for design of plates and plate assemblies against the ultimate limit states of: - plastic failure; - cyclic plasticity; - buckling; - fatigue. (9) Overall equilibrium of the structure (sliding, uplifting, or overturning) is not included in this document. Special considerations for specific applications are available in the relevant applications parts of EN 1993. (10) The rules in this document refer to plate assemblies that are fabricated using unstiffened or stiffened plates or panels. The document is also applicable to the design of individual plates or panels that are predominantly subject to actions transverse to the plane of each plate. Both frictional actions on the plate surface and forces imposed by adjacent components of the plate assembly also induce in-plane actions in each plate. (11) This document gives algebraic rules and guidance to account for bending with small membrane forces in the individual plates or panels. Where an unstiffened or stiffened plates or panels is subject to significant magnitudes of both bending and in-plane forces, the computational analysis procedures of this document apply. (12) Where no application part defines a different range, this document applies to structures within the following limits: - design metal temperatures within the range −50 °C to +100 °C; - the geometry of individual plate segments is limited to rectangular, triangular and trapezoidal shapes with b/t greater than 20, or b1/t greater than 20, as appropriate (see Figure 3.2); - Single plate elements are treated as flat where the deviation from flatness e0 meets the condition (see Figure 9.1). Where this criterion is not met, it is appropriate to treat the plate as a shell panel (see EN 1993-1-6). 1.2 Assumptions (1) Unless specifically stated, the provisions of EN 1990, EN 1991 (all parts) and EN 1993 (all parts) apply. (2) The design methods given in prEN 1993-1-7 are applicable if: - the execution quality is as specified in EN 1090 2, and - the construction materials and products used are as specified in the relevant parts of EN 1993 (all parts), or in the relevant material and product specifications. (3) The provisions in this document apply to materials that satisfy the brittle fracture provisions given in EN 1993-1-4 and EN 1993-1-10. (4) In this document, it is assumed that wind loading, seismic actions and bulk solids flow can, in general, be treated as quasi-static actions. ...

(1) EN 1993-1-9 gives methods for the assessment of fatigue resistance of members, connections and joints subjected to fatigue loading. (2) These methods are derived from fatigue tests with large scale specimens, that include effects of geometrical and structural imperfections from material production and execution (e.g. the effects of tolerances and residual stresses from welding). NOTE 1 For tolerances see EN 1090. The choice of the execution standard may be given in the National Annex, until such time as EN 1090 is published. NOTE 2 The National Annex may give supplementary information on inspection requirements during fabrication. (3) The rules are applicable to structures where execution conforms with EN 1090. NOTE Where appropriate, supplementary requirements are indicated in the detail category tables. (4) The assessment methods given in this part are applicable to all grades of structural steels, stainless steels and unprotected weathering steels except where noted otherwise in the detail category tables. This part only applies to materials which conform to the toughness requirements of EN 1993-1-10. (5) Fatigue assessment methods other than the R-N methods as the notch strain method or fracture mechanics methods are not covered by this part. (6) Post fabrication treatments to improve the fatigue strength other than stress relief are not covered in this part. (7) The fatigue strengths given in this part apply to structures operating under normal atmospheric conditions and with sufficient corrosion protection and regular maintenance. The effect of seawater corrosion is not covered. Microstructural damage from high temperature (> 150 °C) is not covered.