Adjustable telescopic aluminium props - Product specifications, design and assessment by calculation and tests

This European Standard specifies materials, design requirements, designation together with assessment methods using both calculations and testing for adjustable telescopic aluminium props which are intended for use on construction sites. It specifies eleven classes of nominal specified values for strengths for adjustable telescopic aluminium props each having a series of maximum extended lengths.

Baustützen aus Aluminium mit Ausziehvorrichtung - Produktfestlegungen, Bemessung und Nachweis durch Berechnung und Versuche

Diese Europäische Norm sieht für Baustützen aus Aluminium mit Ausziehvorrichtung, die für die Verwendung auf Baustellen bestimmt sind, Festlegungen vor für Werkstoffe, Konstruktion, Bezeichnung sowie Nachweisverfahren durch Berechnung und Versuch.
Diese Europäische Norm legt elf Klassen nominell festgelegter Werte der Tragfähigkeit für Baustützen aus Aluminium mit Ausziehvorrichtung fest. Jede Klasse hat eine Reihe maximaler Auszugslängen.

Etais télescopiques réglables en aluminium - Spécifications du produit, conception et évaluation par calculs et essais

La présente Norme européenne spécifie les matériaux, les exigences de conception, la désignation et les
méthodes d'évaluation utilisant les calculs et les essais pour les étais télescopiques réglables en aluminium
qui sont destinés à une utilisation sur des chantiers de construction.
Elle spécifie onze classes de valeurs de résistances nominales pour les étais télescopiques réglables en
aluminium, chaque classe ayant une série de longueurs d'extension maximale.

Nastavljive aluminijaste teleskopske podpore - Specifikacije izdelka, oblikovanje in ocena z izračunom in preskusi

Ta evropski standard določa materiale, zahteve za oblikovanje in označevanje skupaj z metodami ocenjevanja na podlagi izračunov in preskusov za nastavljive aluminijaste teleskopske podpore, namenjene za uporabo na gradbiščih. Opredeljuje enajst razredov določenih nazivnih vrednosti za trdnost nastavljivih aluminijastih teleskopskih podpor, pri čemer ima vsaka vrsto maksimalnih podaljšanih dolžin.

General Information

Status
Published
Publication Date
11-Jun-2012
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
06-Jun-2012
Due Date
11-Aug-2012
Completion Date
12-Jun-2012

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2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Baustützen aus Aluminium mit Ausziehvorrichtung - Produktfestlegungen, Bemessung und Nachweis durch Berechnung und VersucheEtais télescopiques réglables en aluminium - Spécifications du produit, conception et évaluation par calculs et essaisAdjustable telescopic aluminium props - Product specifications, design and assessment by calculation and tests91.220Gradbena opremaConstruction equipment77.150.10Aluminijski izdelkiAluminium productsICS:Ta slovenski standard je istoveten z:EN 16031:2012SIST EN 16031:2012en,fr,de01-september-2012SIST EN 16031:2012SLOVENSKI
STANDARD



SIST EN 16031:2012



EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN 16031
May 2012 ICS 91.220 English Version
Adjustable telescopic aluminium props - Product specifications, design and assessment by calculation and tests
Etais télescopiques réglables en aluminium - Spécifications du produit, conception et évaluation par calculs et essais
Baustützen aus Aluminium mit Ausziehvorrichtung - Produktfestlegungen, Bemessung und Nachweis durch Berechnung und Versuche This European Standard was approved by CEN on 28 April 2012.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre:
Avenue Marnix 17,
B-1000 Brussels © 2012 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 16031:2012: ESIST EN 16031:2012



EN 16031:2012 (E) 2 Contents PageForeword . 4Introduction . 51 Scope . 62 Normative references . 63 Terms and definitions . 64 Symbols . 95 Classification . 106 Designations . 117 Materials . 128 Requirements . 128.1 Tubes . 128.2 Welding . 128.3 Length adjustment device . 128.4 Permanent prevention against unintentional disengagement . 128.5 Anti hand trap . 138.6 Overlapping length . 138.7 Endplates . 149 Verification . 149.1 General . 149.2 Calculation of prop strength. 159.2.1 General . 159.2.2 Imperfections . 159.2.3 Behaviours of inner and outer tube . 179.2.4 Boundary conditions . 179.2.5 Verification of prop strength . 219.3 Verification of the strength of length adjustment device . 229.4 Verification of the prevention against unintentional disengagement . 229.5 Confirmation of the calculation results by testing . 2210 Tests . 2210.1 General . 2210.2 Detail tests . 2210.2.1 Compression tests on unthreaded tubes . 2210.2.2 Compression tests on threaded tube . 2310.2.3 Bending tests on threaded tube . 2510.2.4 Tests for the limit eccentricities of prop ends . 2710.2.5 Compression tests on length adjustment device . 3010.3 Test of the prevention against unintentional disengagement . 3010.3.1 Purpose of test . 3010.3.2 Test arrangement . 3110.3.3 Evaluation of test results . 3110.4 Confirmation test for the prop strength . 3110.4.1 Material properties . 3110.4.2 Global test . 3211 Documentation of test results . 32SIST EN 16031:2012



EN 16031:2012 (E) 3 Page12 Marking . 3213 Assessment . 3314 User manual . 33Annex A (informative)
Ongoing production control . 34Bibliography . 36
SIST EN 16031:2012



EN 16031:2012 (E) 4 Foreword This document (EN 16031:2012) has been prepared by Technical Committee CEN/TC 053 “Temporary works equipment”, the secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by November 2012, and conflicting national standards shall be withdrawn at the latest by November 2012. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. SIST EN 16031:2012



EN 16031:2012 (E) 5 Introduction This European Standard deals with the more common types of adjustable telescopic aluminium props in current use. It is not intended to prevent development of other types of props. For example, props may have hinged ends or other length adjustment devices or be made of other materials. Whilst such props cannot comply with this European Standard, it is nevertheless recommended that the principals of this European Standard be considered in the design and assessment of such props. This European Standard is a product standard primarily for use in the field of falsework and formwork standardized in EN 12812. The specified values for load bearing capacity listed in this European Standard are figures for classification. For site use, Fγ and Mγ can be found in EN 12812. SIST EN 16031:2012



EN 16031:2012 (E) 6 1 Scope This European Standard specifies materials, design requirements and designation together with assessment methods using both calculations and testing for adjustable telescopic aluminium props which are intended for use on construction sites. It outlines eleven classes of nominal specified values for strengths for adjustable telescopic aluminium props, each having a series of maximum extended lengths. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 74-1, Couplers, spigot pins and baseplates for use in falsework and scaffolds — Part 1: Couplers for tubes – Requirements and test procedures EN 74-2, Couplers, spigot pins and baseplates for use in falsework and scaffolds — Part 2: Special couplers — Requirements and test procedures EN 1999-1-1, Eurocode 9: Design of aluminium structures — Part 1-1: General structural rules EN 1065:1998, Adjustable telescopic steel props — Product specifications, design and assessment by calculation and tests EN 1090-3:2008, Execution of steel structures and aluminium structures — Part 3: Technical requirements for aluminium structures EN 10204:2004, Metallic materials — Types of inspection documents EN 12811-1, Temporary works equipment — Part 1: Scaffolds — Performance requirements and general design EN 12811-2:2004, Temporary works equipment — Part 2: Information on materials EN 12811-3:2002, Temporary works equipment — Part 3: Load testing EN 12812, Falsework — Performance requirements and general design 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 adjustable telescopic aluminium prop compression member consisting of two tubes circular or profiled which are telescopically displaceable within each other with a length adjustment device with threaded inner tube (see Figure 1) or with a pin inserted into holes in the inner tube and a mean of fine adjustment using a threaded collar (see Figure 2) Note 1 to entry: Such props are normally used as a temporary vertical support in construction works. 3.2 endplate plate which is fixed at right angles to one end of inner and outer tube SIST EN 16031:2012



EN 16031:2012 (E) 7 3.3 collar nut nut internally threaded to provide fine length adjustment to the prop to transfer the force from the inner to the outer tube either to a threaded inner tube or through a pin 3.4 inner tube smaller tube that may be profiled or provided with thread or holes for the coarse adjustment of the prop 3.5 outer tube larger tube that may be profiled, one end of which could be threaded externally (see Figure 1 and 2) 3.6 length at maximum extension nominal distance measured between the outside faces of the endplates when the prop is in the fully extended position (fully opened) 3.7 length at minimum extension nominal distance between the outside faces of endplates when the prop is in the fully closed position 3.8 minimum working length nominal distance between the outside faces of the endplates necessary to allow safely the dismounting and removal of prop 3.9 safety devices devices to prevent unintentional disengagement of the inner and outer tube and/or devices to guarantee the minimum overlapping length 3.10 pin part of the length adjustment device which is inserted through the inner tube holes and is secured to the prop 3.11 working load nominal characteristic strength of the prop for different classes divided by at least the safety factors given in EN 12812 Note 1 to entry: Safety factors can be greater in national regulations.
SIST EN 16031:2012



EN 16031:2012 (E) 8
Key1 endplates 2 outer tube 3 inner tube 4 length adjustment device (collar) 5 locking (security) device Figure 1 — Example of adjustable telescopic aluminium prop (type 1)
Key1 endplate 2 outer tube 3 inner tube 4.1 attached pin
4.2 collar nut 4.3 handle 5 central hole 6 connection holes
7 pin hole Figure 2 — Example of adjustable telescopic aluminium prop (type 2) SIST EN 16031:2012



EN 16031:2012 (E) 9 4 Symbols Symbol Designation Unit Di outer diameter of the inner tube mm mD collar nut major thread diameter mm pD diameter of the pin mm coreb,e eccentricity at the base at which the spring becomes effective mm e(N) limiting eccentricity of the axial forces mm cb spring stiffness N ⋅ mm/rad limitb,e unit eccentricity at the base mm b,0e initial eccentricity at the base mm et eccentricity at the top mm fy yield strength N/mm2 actyf actual yield strength N/mm2 nomyf nominal yield strength N/mm2 f0 characteristic value of proof strength at the transitions point between prop and base plate
N/mm2 f0,HAZ characteristic value of proof strength at the transitions point between prop and base plate determined by taking the heat effected zone into account N/mm2 l actual extension length of the prop m maxl length of a prop at maximum extension m 0l overlapping length mm plM plastic moment resistance of the cross section kN ⋅ m Npl,M reduced plastic moment resistance of the cross section kN ⋅ m N normal (axial) force kN NR,k characteristic compression resistance kN iC,N ideal buckling force kN plN nominal plastic compression resistance of the cross section kN R strength of a prop kN tb,R bearing resistance of the tube kN pR shear resistance of the pin kN uR failure load of a test kN
SIST EN 16031:2012



EN 16031:2012 (E) 10 Symbol Designation Unit acty,R actual characteristic strength of the prop class y where y corresponds to classes from A to W kN ky,R nominal characteristic strength of the prop class y where y corresponds to classes from A to W kN ty,R lowest evaluated test result in the global test kN ay,R average value test result in the global test kN kad,R characteristic strength in compression kN V vertical load kN ∆ϕ0 angle of inclination between the inner and outer tube rad Mγ partial safety factor for the resistance 1 M1γ,M2γ splitted partial safety factors for the material 1 Fγ partial safety factor for the action 1
5 Classification Adjustable telescopic aluminium props shall be classified according to its specified value for nominal characteristic strength Ry,k given in Table 1 (load classes) and its maximal extension length maxlgiven in Table 2 (length classes). Table 1 — Load classes of adjustable telescopic aluminium props Load class Specified value for nominal characteristic strength Ry,k A kN0,440,512max≤⋅ll B kN0,510,682max≤⋅ll C kN5,590,1022max≤⋅ll D 34,0 kN E 51,0 kN R 66,0 kN S 82,5 kN T 99,0 kN U 115,5 kN V 132,0 kN W 148,5 kN
SIST EN 16031:2012



EN 16031:2012 (E) 11 Where maxl is the length at the maximum extension in metres; l is the actual extension length in metres. Table 2 — Length classes of adjustable telescopic aluminium props Length class Length at maximum extension lmax 10 1,00 m ≤ maxl ≤ 1,49 m 15 1,50 m ≤ maxl ≤ 1,99 m 20 2,00 m ≤ maxl ≤ 2,49 m 25 2,50 m ≤ maxl ≤ 2,99 m 30 3,00 m ≤ maxl ≤ 3,49 m 35 3,50 m ≤ maxl ≤ 3,99 m 40 4,00 m ≤ maxl ≤ 4,49 m 45 4,50 m ≤ maxl ≤ 4,99 m 50 5,00 m ≤ maxl ≤ 5,49 m 55 5,50 m ≤ maxl ≤ 5,99 m 60 6,00 m ≤ maxl ≤ 6,49 m 65 6,50 m ≤ maxl ≤ 6,99 m 70 7,00 m ≤ maxl ≤ 7,50 m
6 Designations EXAMPLE EN 16031 R65/49 T1 M Designation of a prop in accordance with EN 16031, class: “R65”, with a minimum extended length: “49” dm, “T1” type 1 with threaded inner tube, “M” with an ongoing production inspection level M:
EN16031R65/49T1 M
European Standard number block
Load class, length class/minimum extended length
Prop type 1 with threaded inner tube
With an ongoing production inspection level
SIST EN 16031:2012



EN 16031:2012 (E) 12 7 Materials Materials shall have a good resistance and be protected against atmospheric corrosion. They
shall be free of any impurities and defects which might affect their satisfactory use. Steels of deoxidation type FU (rimming steels) are not permitted. Materials should be selected from the relevant existing European and International Standards and, whenever applicable, should be in accordance with the following standards: EN 12811-2:2004 (in particular Clause 6) and EN 1999-1-1 for aluminium. 8 Requirements 8.1 Tubes For the purposes of assessment, the method of making holes shall be stated on the relevant drawings. NOTE The preferred method of forming holes is by drilling. For aluminium profiled tubes, the minimum nominal wall thickness shall be at least 2 mm. For tubes for which it is possible to attach EN 74-1 and EN 74-2 couplers see EN 12811-1. 8.2 Welding The welding shall be carried out in accordance with execution class 2 (EXC 2) of EN 1090-3:2008. 8.3 Length adjustment device A prop shall be provided with a length adjustment device to modify the length from the minimum to the maximum extension. The adjustment device shall be one of two types: 1) a threaded collar connected to the outer tube with a threaded inner tube (type 1) (see Figure 1); or 2) a pin inserted into holes in the inner tube and a threaded collar connected to the thread in the outer tube (type 2) (see Figure 2). 8.4 Permanent prevention against unintentional disengagement The inner and outer parts of a prop shall be prevented from being permanently separated except by intentional action. One of the following methods shall by applied:  safety method 1: permanent locking connection (see Figure 3a); NOTE Safety method 1 is usually used for prop type 2.  safety method 2: an automatic safety device and an additional permanent locking connection (see Figure 3b);  safety method 3: two independent automatic safety devices arranged on the circumference not opposed each other (see Figure 3c);  safety method 4: an automatic safety device locked by an additional automatic permanent safety device (see Figure 3d). SIST EN 16031:2012



EN 16031:2012 (E) 13 The additional permanent safety device shall be so designed that the safety device can only be detached or attached by at least two consecutive deliberate manual actions. Key 1 permanent locking connection 2 automatic safety device 3 additional automatic safety device 4 spring Figure 3 — Examples of methods of locking safety devices
8.5 Anti hand trap For prop type 2, when the prop is fully closed without the pin inserted, there shall remain at least 100 mm clearance between the endmost part of the outer tube and the inside of the endplate. 8.6 Overlapping length There shall be an overlapping length between the outer and inner tube, l0, of at least 300 mm when the prop is fully open. SIST EN 16031:2012



EN 16031:2012 (E) 14 8.7 Endplates Props with endplates of classes A, B, C, D and E shall be in accordance with 7.5 of EN 1065:1998. For classes R, S, T, U, V and W endplates shall be square or rectangular. Endplates shall have at least two holes for connection purposes. If a central hole is required in the endplates, it shall have a minimum diameter of 28 mm. Plain aluminium endplates shall be made from material having a minimum proof stress of 195 N/mm2. They shall have a minimum nominal thickness of 10 mm.
Profiled endplates shall have a spring stiffness and a bending resistance at least equal to that of plain endplates. At corners which would otherwise be sharp, the radius shall be at least 5 mm. 9 Verification 9.1 General The properties of a prop shall be verified following the steps in Table 3. The actual characteristic strength acty,R of a prop shall be verified both with the outer tube at the bottom and with the inner tube at the bottom. The actual characteristic strength of a prop acty,R shall be verified at maximum extension for the classes A, B or C in the fully closed extension and also in the most unfavourable extension in between. The most unfavourable extension is the length with the smallest quotient acty,R/ky,R. For all extended lengths, the actual characteristic strength acty,R of a prop shall be at least equal to the nominal characteristic strength Ry,k specified in Table 1. Table 3 — Verification steps Step Property Verification method 1 Actual characteristic strength acty,R Determined by calculation supported by detail tests in accor-dance to 10.2 and confirmed by tests in accordance with 10.4 2 Characteristic strength of length adjustment device Determined by tests in accordance with 9.3 3 Prevention against unintentional disengagement Tests in accordance with 10.3
The global analysis to determine the internal forces and moments shall use elastic analysis design principles, assuming that the behaviour of the material is linear at all stress levels. The resistances of cross sections may be calculated by using plastic stress distributions. For the global analysis, the second order theory shall be used, taking into account the influence of the deformations of the structure on the internal forces and moments. The values for resistance in compression, bending moment, stiffness and eccentricities at the base shall be defined or calculated or determined by tests in accordance with 10.2 to support the analysis model chosen. SIST EN 16031:2012



EN 16031:2012 (E) 15 9.2 Calculation of prop strength 9.2.1 General Characteristic strength calculations shall be carried out using the structural model given in Figure 4. The deformation of the inner tube in the overlap zone shall be taken into account. Additional contact points which occur when the looseness between the inner and outer tube have been taken up may also be allowed for. 9.2.2 Imperfections 9.2.2.1 Angle of inclination ∆ϕ0 The angle of inclination ∆ϕ0 (see Figure 4) caused by the clearance between the tubes in the overlap zone shall be determined from the nominal dimensions of the components. For detail X see Figure 5 or Figure 8. SIST EN 16031:2012



EN 16031:2012 (E) 16
a) Prop type 1 b) Prop type 2 c) Structural model
Key 1 end plate on top 2 threaded inner tube 3 outer tube 4 end plate on the base 5 inner tube with holes
et eccentricity at the top w0 preflexure ∆ϕ0 angle of inclination V vertical load (Ry,k or Ry,act) Figure 4 — Structural model for the verification of the actual characteristic strength of different prop types 9.2.2.2 Preflexure In addition to the angle of inclination, a sine-shaped preflexure of the prop as a whole with a maximum offset w0 in accordance with the verification procedure shall be assumed:  verification procedure elastic-elastic: w0 = l/375  verification procedure elastic-plastic: w0 = l/250 SIST EN 16031:2012



EN 16031:2012 (E) 17 9.2.3 Behaviours of inner and outer tube 9.2.3.1 Rigidity The axial compression stiffness and the bending stiffness of the tubes shall be calculated or determined by detailed tests in accordance with 10.2. For the inner tube of type 2 props, the reduction of the flexural rigidity due to the holes shall be calculated; for circular tubes in accordance with Annex A of EN 1065:1998. If the holes are not produced by drilling, the resultant deformations of the tube shall be measured and the sectional properties of the deformed tube calculated. 9.2.3.2 Resistances of tubes The characteristic moment resistance Mpl,k and the characteristic compression resistance Npl,k of the tubes shall be calculated or determined by detail tests in accordance with 10.2. The moment capacity MR,k(N) shall be determined, taking into account the effects of axial forces. This capacity MR,k(N) may be calculated for circular and profiled tubes using Formula (1): ⋅⋅=kpl,kpl,kR,2cos)(NNMNMπ (1) where MR,k(N) is the reduced plastic resistance moment allowing for axial force; Mpl,k is the characteristic moment resistance of the gross cross-section (αpl ≤ 1,25); N is the axial force (Ry,k, (see Table 1 or Ry,act)); Npl,k is the characteristic compression resistance of the gross cross section. Local buckling effects should be evaluated according to EN 1999-1-1 or taken into consideration according to 10.2.1. NOTE 1 In case of verification procedure elastic-elastic, the resistance of the tubes needs to be calculated using the linear stress distribution. NOTE 2 Equations for determining the structural properties of a perforated circular tube, are to be taken into account in accordance with Annex A of EN 1065:1998. 9.2.4 Boundary conditions 9.2.4.1 Eccentricities at the ends 9.2.4.1.1 Eccentricity at the top At the top of the prop an eccentricity et = 10 mm (see Figure 4) shall be assumed. SIST EN 16031:2012



EN 16031:2012 (E) 18 9.2.4.1.2 Eccentricity at the base At the base of the prop, one of two structural models, a) or b), for the calculation of the eccentricities shall be used. Structural model a) The following eccentricities shall be assumed (see Figure 5): 10b,40.0De⋅=; 1coreb,25.0De⋅−=; {})(;50.0min1limb,NeDeit⋅−=.
Figure 5 — Eccentricities at the base plate — structural model a) where 1D effective diameter at the base in millimetres (see Figure 6). The effective diameter 1D shall be calculated by taking both the outer diameter of the profile and, if welded to the profile, the thickness of the endplate, into account. The following calculations and Figure 6 are examples:  welded endplate: tDD⋅+=21  non welded endplate: DD=1 SIST EN 16031:2012



EN 16031:2012 (E) 19
Figure 6 — Effective diameter 1D
NOTE The minimum elastic bending resistance of the profile may correspond with the maximum effective diameter D1. A simplified analysis may use the minimum of bending resistance and minimum effective diameter. Otherwise, calculations should be performed for both directions using corresponding parameters. )(Ne limiting eccentricity of the axial forces N may be determined either  by detail tests according 10.2.4, or  by the following simplified calculation when assuming a load-path via a partial area solely under compression (see Figure 7). For the calculation )(Ne is the distance between the centre of gravity C and the centre of gravity S(A(N)) of an ideal necess
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