draft uganda standard - world trade organization · 2018. 11. 1. · us iso 7989-2, steel wire and...

DRAFT UGANDA STANDARD

DUS 193-2

First Edition 2018-10-dd

Reference number DUS 193-2: 2018

© UNBS 2018

Steel wires and wire products for fencing — Part 2: Chain link — Specification

DUS 193-2: 2018

ii © UNBS 2018 – All rights reserved

Compliance with this standard does not, of itself confer immunity from legal obligations

A Uganda Standard does not purport to include all necessary provisions of a contract. Users are responsible for its correct application

© UNBS 2018

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilised in any form or by any means, electronic or mechanical, including photocopying and microfilm, without prior written permission from UNBS.

Requests for permission to reproduce this document should be addressed to

The Executive Director Uganda National Bureau of Standards P.O. Box 6329 Kampala Uganda Tel: +256 414 333 250/1/2/3 Fax: +256 414 286 123 E-mail: [email protected] Web: www.unbs.go.ug

mailto:[email protected]

DUS 193-2:2018

© UNBS 2018 – All rights reserved iii

Contents Page

Foreword ............................................................................................................................................................. v

1 Scope ...................................................................................................................................................... 1

2 Normative references ............................................................................................................................ 1

3 Terms and definitions ........................................................................................................................... 1 3.1 chain link mesh ...................................................................................................................................... 1 3.2 mesh opening ........................................................................................................................................ 2 3.3 mesh geometry ...................................................................................................................................... 2 3.4 ends of mesh ......................................................................................................................................... 2 3.5 dimension of a chain link panel or roll ................................................................................................ 2 3.6 Connecting elements ............................................................................................................................ 2

4 Description of use and application ...................................................................................................... 2

5 Chain link wire mesh panels and rolls ................................................................................................ 2 5.1 Base material ......................................................................................................................................... 2 5.2 Mesh panel or roll dimensions ............................................................................................................. 3 5.3 Mesh opening ........................................................................................................................................ 3 5.4 Ends of meshes ..................................................................................................................................... 4 5.5 Information to be supplied by the purchaser ..................................................................................... 5

6 Requirements ......................................................................................................................................... 6 6.1 Tensile strength of wires ...................................................................................................................... 6 6.2 Mesh sizes, geometry and wire diameter............................................................................................ 6 6.3 Mesh tolerances .................................................................................................................................... 7 6.4 Coating ................................................................................................................................................... 7

7 Sampling and testing ............................................................................................................................ 7 7.1 Tensile strength and elongation testing of mesh panels .................................................................. 7 7.1.1 General ................................................................................................................................................... 7 7.1.2 Test specimen ........................................................................................................................................ 7 7.1.3 Test apparatus ....................................................................................................................................... 7 7.1.4 Test procedure ....................................................................................................................................... 8 7.1.5 Test report .............................................................................................................................................. 8 7.2 Punch test methods .............................................................................................................................. 9 7.3 Test on connected mesh panels and connection elements ............................................................. 9 7.4 Abrasion ................................................................................................................................................. 9 7.5 Corrosion spread test (for organic coatings only) ............................................................................ 9 7.6 Ductility test ........................................................................................................................................... 9

8 Marking ................................................................................................................................................. 10

9 Packaging ............................................................................................................................................. 10

Annex A (normative) ....................................................................................................................................... 11 A.1.1 General ................................................................................................................................................. 11 A.1.2 Test specimen ...................................................................................................................................... 11 A.1.3 Test equipment .................................................................................................................................... 11 A.1.4 Test procedure ..................................................................................................................................... 12 A.1.5 Test procedure ..................................................................................................................................... 12 A.2 Punch test for large area load transfer ............................................................................................. 13 A.2.1 Load bearing capacity test procedures ............................................................................................ 13 B.2.2 Measurements and observations ...................................................................................................... 15 B.2.3 Test report ............................................................................................................................................ 15

Annex B (normative) ....................................................................................................................................... 17

DUS 193-2: 2018

iv © UNBS 2018 – All rights reserved

B.1.1 General ................................................................................................................................................. 17 B.1.2 Test specimen ..................................................................................................................................... 17 B.1.3 Test apparatus .................................................................................................................................... 17 B.1.4 Test procedure .................................................................................................................................... 18 B.1.5 Test report ........................................................................................................................................... 18

Bibliography ..................................................................................................................................................... 20

DUS 193-2:2018

© UNBS 2018 – All rights reserved v

Foreword

Uganda National Bureau of Standards (UNBS) is a parastatal under the Ministry of Trade, Industry and Cooperatives established under Cap 327, of the Laws of Uganda, as amended. UNBS is mandated to co-ordinate the elaboration of standards and is

(a) a member of International Organisation for Standardisation (ISO) and

(b) a contact point for the WHO/FAO Codex Alimentarius Commission on Food Standards, and

(c) the National Enquiry Point on TBT Agreement of the World Trade Organisation (WTO).

The work of preparing Uganda Standards is carried out through Technical Committees. A Technical Committee is established to deliberate on standards in a given field or area and consists of key stakeholders including government, academia, consumer groups, private sector and other interested parties.

Draft Uganda Standards adopted by the Technical Committee are widely circulated to stakeholders and the general public for comments. The committee reviews the comments before recommending the draft standards for approval and declaration as Uganda Standards by the National Standards Council.

The committee responsible for this document is Technical Committee UNBS/TC 04, Mechanical Engineering and Metallurgy.

This US 193 series edition cancels and replaces the first edition (US 193:2001), which has been technically revised.

US 193 consists of the following parts, under the general title Introductory element — Main element:

Part 1: Barbed wires — Specification

Part 2: Chain link — Specification

DRAFT UGANDA STANDARD DUS 193-2: 2018

© UNBS 2018 – All rights reserved 1

Steel wires and wire products for fencing — Part 2: Chain link — Specification

1 Scope

This standard specifies the requirements for the dimensions, tolerances, coatings, test methods and delivery conditions of chain link steel wire mesh products specified for fencing and civil engineering purposes.

2 Normative references

The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

US ISO 7989-2, Steel wire and wire products — Non-ferrous metallic coatings on steel wire — Part 2: Zinc or zinc-alloy coating

ISO 7500-1, Metallic materials — Calibration and verification of static uniaxial testing machines — Part 1: Tension/compression testing machines — Calibration and verification of the force - measuring system

US ISO 6892-1, Metallic materials — Tensile testing — Part 1: Method of test at room temperature

US ISO 16120-1:2011, Non-alloy steel rod for drawing and/or cold rolling — Part 1: General requirements

US ISO 16120-2:2017, Non-alloy steel wire rod for conversion to wire — Part 2: Specific requirements for general purpose wire rod

US ISO 22034-2, Steel wire and wire products — Part 2: Tolerances on wire dimensions

ISO 10474, Steel and steel products — Inspection documents

ISO 7802, Metallic materials — Wire — Wrapping test

3 Terms and definitions

For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at http://www.iso.org/obp

3.1 chain link mesh

mesh manufactured from interlocking of steel wire which provide approximately square or rhomboidal meshes

http://www.iso.org/obp

DUS 193-2: 2018

2 © UNBS 2018 – All rights reserved

3.2 mesh opening

diameter of inner circle of single mesh (rhomboid or quadratic shape), Di

3.3 mesh geometry

geometry of a single mesh defined by the dimensions, length (X) and width (Y), and angle of mesh opening (α) of two connected wires.

3.4 ends of mesh

connection of two wires at the outer faces of the mesh along the longitude direction

3.5 dimension of a chain link panel or roll

length and width expressed in meters

3.6 Connecting elements

elements which serve to connect chain link mesh panels (e.g. wires, wire ropes, clips, shackle, …)

4 Description of use and application

The typical use of the considered products in civil engineering is for perimeter and security netting, retaining of unstable slopes, controlling and preventing of rock fall and loose debris flow along roads, highways and railways, urban areas, mines and quarries and related applications.

5 Chain link wire mesh panels and rolls

5.1 Base material

The base material of chain link wire mesh shall be for medium and high carbon steel wire produced from wire rod complying with US ISO 16120-1 and US ISO 16120-2.

The diameter of the wire shall range from 1.0 mm and 6.0 mm with tolerances as defined in accordance with US ISO 22034-2.

DUS 193-2: 2018


5.2 Mesh panel or roll dimensions

The chain link mesh dimensions and geometry are defined as shown in Figure 1 (a) for rhomboid shape and in Figure 1(b) for rectangular shape:

Figure 1.a — Rhomboidal shaped chain link

Figure 1.b — Rectangular shaped chain link

Key W width of panel or roll

L length of panel or roll

Figure 1 — Panel or roll dimensions

5.3 Mesh opening

The mesh opening is defined as shown in Figure 2:

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Key Di inner diameter of mesh opening X mesh lenght (in direction of the length of the roll) Y mesh width (in direction of width of the roll) α angle of mesh opening

Figure 2 — Mesh opening

5.4 Ends of meshes

The ends of meshes can be manufactured as shown in Table 1 and figures 3 to 6:

Table 1 — Types of mesh end

Type Description

A Knuckled end

B Knotted end

C Barbed end

D Twisted knuckle end

Figure 3 — Knuckled end (Type A)

DUS 193-2: 2018


Figure 4 — Knotted ends (Type B)

Figure 5 — Barbed ends (Type C)

Figure 6 — Twisted knuckle end (Type D)

5.5 Information to be supplied by the purchaser

The following information shall be supplied by the purchaser at the time of enquiry and order:

a) number of this standard;

b) quantity of rolls or panels;

c) size of the rolls or panels in m (W x L);

d) mesh opening dimensions and geometry (Di, X, Y, α)

e) wire diameter d in mm;

f) minimum wire tensile strength in N/mm2;

g) end of mesh specification according to table 1 – types of mesh end — Types of mesh end

h) minimum mesh tensile strength Tmax in kN/m and test direction (longitudinal and transversal);

i) Maximum mesh elongation at break of first wire in the tensile strength test according to 7.1 lmax for a max. pretension mesh of 3% of Pspec

j) wire material specification (number of bendings, number of torsion)

k) coating type and class of coating or material specification (US ISO 7989-2);

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l) inspection documentation requirements.

6 Requirements

6.1 Tensile strength of wires

The base wire for chain link shall have a minimum tensile strength of 350 N/mm2 when tested in accordance with US ISO 6892-1.

6.2 Mesh sizes, geometry and wire diameter

The chain link shall be manufactured in different sizes using corresponding wire diameters as given in Table 2: The geometry of the mesh opening shall either be rhomboidal or rectangular.

Table 2 – Typical mesh sizes, wire tolerances

Inner diameter of mesh opening, Di

(mm)

Angle of mesh opening, α

(°)

Wire diameter, d (mm) a)

25 50-130° 2

2.5

40 50-130°

2

2.5

3

3.5

45 50-130°

2

2.5

3

3.5

50 50-130°

2

3

4

5

60 50-130°

2

3

4

5

65 50-130°

2

3

4

5

75 50-130°

2

3

4

5

6

80 50-130°

2

3

4

5

6

100 50-130°

2

3

4

5

DUS 193-2: 2018


6 a) 1.5 mm is also possible related to security fencing.

6.3 Mesh tolerances

All mesh dimensions and geometry measures shall be within tolerances of +/-3%

6.4 Coating

6.4.1 The steel wires used shall be coated in accordance with the US ISO 7989-1 and US ISO 7989-2, with at least class D. Method of assessment and acceptance criteria for zinc and zinc alloy coating weight are prescribed in US ISO 7989-2. The corrosion resistance of the connecting elements (e.g. wires, wire ropes, clips, shackle) shall be the same class as the wires used.

6.4.2 Wire used for chain link can also be additionally organic coated. The polymeric coating material mechanical characteristics (tensile strength and elongation), after exposure to UV-rays, the number of hours QUV-A (ISO 4892-3 exposure mode 1) shall not decrease by more than 25% from the initial test results.

7 Sampling and testing

7.1 Tensile strength and elongation testing of mesh panels

7.1.1 General

The aim of this test is to determine the maximum tensile strength (Tmax) of chain link wire mesh in longitudinal and transverse direction.

7.1.2 Test specimen

The chain link wire mesh specimens shall be representative of proper field construction as to materials and geometry. The test specimen shall have identical ends with knots according to Table 1. The dimension of a specimen shall be 1.0 x 1.0 m (-10%/+20%).

7.1.3 Test apparatus

The test apparatus consists of traction machine and rigid steel beams conforming to ISO 7500-1 class A (A and B, see Figure A.1) to allow the specimen to be connected to them at all four sides.

Figure 7 — Test arrangement (Direction of the mesh)

Key 1 fixed frame

DUS 193-2: 2018


2 movable beam

3 lateral fixation points

4 longitudinal fixation points

7.1.4 Test procedure

The tests shall be run with the load applied in longitudinal or transverse mesh direction. The specimen is fixed at all peripheral mesh openings at all four sides, longitudinal and transverse fixation points. The test shall be carried out thrice with three specimens of the same type.

The fixations shall rotate and shift freely without any friction to allow the steady displacement of specimen fixation points.

The bolts of all fixation pints of the mesh shall have a diameter between 10 % - 20% of Di (diameter of the mesh opening)

The load shall initially be taken to a pre-load of 3% of the specified minimal tensile strength (Pspec) by the supplier. The load P is then applied at a uniform rate between 80 mm/minute to 90 mm/minute. Loading shall then continue uniformly until first fracture of an individual wire or another damage of the mesh occurs (P=Tmax).

The load and elongation of the mesh in longitudinal direction should be measured continuously with an appropriate measuring device with resolution of not more than 1 % of the test specimen specified minimal tensile strength (PSpec) and length.

7.1.5 Test report

The test report shall contain the following information:

a) detailed and particular description of all three test specimen:

i) mesh construction;

ii) mesh panel size;

iii) knot type,

iv) mesh opening geometry;

v) mesh characteristics; and

vi) specifications (diameter of wires, breaking force of wire, specified minimal tensile strength);

b) date of test;

c) testing institution;

d) nominal dimensions W and L of test specimen, number of repetitions in both directions;

e) initial dimensions of test specimen with applied preload;

f) description of testing apparatus;

g) direction of the testing (longitudinal and transverse)

h) load – elongation diagram, see Figure 8 (the load expressed by tensile strength);

i) description of failure mode;

j) elongation lmax at maximum tensile strength, Tmax when the first break of the mesh occurs; and

k) maximum tensile strength (Tmax) in kN and (Tmax/b) in kN/m, where Tmax is the breaking force and b is the nominal width of the installed specimen (number of repetitions orthogonal to the testing direction x mesh length (X) or width (Y).

DUS 193-2: 2018


Figure 8 — Load elongation diagram

7.2 Punch test methods

If a perpendicular load transfer of the mesh is a decisive issue a suitable punch test has to be performed according to Annex A.2.

7.3 Test on connected mesh panels and connection elements

If the aim of the mesh is to transfer the complete tensile strength of the mesh by the connection elements the mesh test with connection elements has to be conducted according to Annex C.

7.4 Abrasion

If abrasion is a design issue an abrasion index test might be necessary to clarify abrasion rates for different applications. The suitable test method shall be defined by the designer.

7.5 Corrosion spread test (for organic coatings only)

7.5.1 The corrosion spread test is relevant for organic coatings to assess, in the event of a local damage to an over sheath, any consequential corrosion of the outer surface of the steel wire core, and ensure that the corrosion effect will remain confined to the damaged area of the covering.

7.5.2 The procedure consists of immersing wire samples 250 mm long in a 5% wt solution of hydrochloric acid (HCl).

7.5.3 Samples are removed from the solution and analyzed after 100 h, 500 h, 1 000 h, 1 500 h, 2 500 h of immersion. The organic coating shall be removed and the length of the corroded wire measured. It is considered as corroded if the diameter of the immersed wire reduces. The average corrosion lengths measured and plotted against time shall show which is the maximum length after witch there is no more increase in corroded length in time. This maximum length measured shall be always less than a mesh repetition. Organic coating shall be UV resistant

7.6 Ductility test

The chain link wires shall be subjected to the wrapping test in accordance with ISO 7802. The line wire shall withstand wrapping and unwrapping eight turns round its own diameter without fracture.

Tmax

Working load 80% of Pspec

DUS 193-2: 2018


8 Marking

Each roll of chain link shall be provided with the following information on a label attached to the chain link roll:

a) manufacturer’s name and address;

b) dimensions of the chain link roll (length and width);

c) diameter of the chain link wire;

d) tensile strength of chain link wire;

e) size of openings;

f) class of coating in accordance with US ISO 7989-2;

g) mass of the chain link roll in kg; and

h) reference number of this Uganda standard;

9 Packaging

Chain link wire mesh shall be supplied in rolls with standard width of 1.0 m to 4.0 m and standard length varying between 15 m – 50 m length but individual measures can be agreed to between the supplier and purchaser.

Mesh sizes (width and length) shall be subjected to a tolerance of ± 3 % measured at right angles between wires.

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Annex A (normative)

A.1 Test method for determination of puncturing bearing resistance

A.1.1 General

For soil nailing the aim of this test is to determine the bearing resistance of the mesh to puncturing V in perpendicular way.

A.1.2 Test specimen

The chain link wire mesh specimens shall be representative as to materials and geometry. The test specimen shall be ended by the same way as during the mesh manufacturing and without any reinforcement elements. The test specimen shall be constituted of panels of dimensions 300 cm x 300 cm (+/- 20%).

A.1.3 Test equipment

The test setup consists of a steel frame and a hydraulic press. Inside the frame there are four U shape profiles with holes and bolts to hold the chain link mesh in its position and with each two threaded bars to adjust to the specimen size and to straighten the mesh equally. The pitch of the holes shall be according to the X and Y dimensions of the mesh. The threaded bars of the U shape profiles run through corresponding holes at the metal frame and are adjusted with screw nuts.

A circular plate with a thickness of 40 mm, a radius of 10 mm at all edges, an outer diameter of 200 mm and a traction bolt in the centre, is positioned in the middle of the test specimen over the guiding nail. The traction bolt has a diameter of 0.8 x Di (Inner diameter of mesh opening).

DUS 193-2: 2018


Figure A.1 — Test apparatus for punching test.

Key 1 rigid steel frame 2 U shape profiles 3 mesh fixation points 4 threaded bars 5 circular plate 6 vertical traction bolt 8 vertical force V

A.1.4 Test procedure

The test specimen is mounted into the four frames and pre tensioned by the two threaded bars and nuts on each side. Pre tensioning should be such that sagging (b) of the mesh in measured at the centre is 30 +/-3 cm.

The circular plate is pulled by means of a traction machine, with a corresponding vertical force V (8). The force V is transmitted directly into the mesh over the bolt and circular plate.

The forces V and the vertical displacement of the circular plate shall be recorded continuously by load cells and appropriate measuring device. The test ends when the mesh fails at the plate location or by the rupture of a first mesh somewhere else.

A.1.5 Test procedure

The test report shall contain:

DUS 193-2: 2018


a) Detailed and particular description of all three test specimen: mesh construction, mesh panel size, knot type, mesh opening geometry, mesh characteristics and specifications (diameter of wires, breaking force of wire, specified minimal tensile strength);

b) Date of test;

c) Testing body;

d) Nominal dimensions W and L of test specimen, number of repetitions in both directions;

e) Nominal dimensions and W and L of test specimen;

f) Diameter of circular plate used;

g) Date of test;

h) Testing body;

i) Vertical displacement at failure and corresponding applied load;

j) Detailed description of failure mode including location and photography;

k) Load – vertical displacement diagram;

A.2 Punch test for large area load transfer

A.2.1 Load bearing capacity test procedures

The test consists in loading a sample of net perpendicularly to its plane by means of a hemispherical-shaped load sharing device (press). The press must be located in the central point of the panel.

The hemisphere of the press is formed by a durable material such as concrete or steel.

The surface of the press must be smooth, without any corners. Any attachment devices fitted on the surface of the press must not interfere in any way with the test piece during the test.

The geometrical characteristics of the press are (Figure A.2):

a) radius of curvature 1 200 mm b) maximum diameter of the sample projected on a plane 1 000 mm c) radius of curvature at the side 50 mm

The test piece is loaded at the intersection of its diagonals (centre of test piece), moving the press with a speed not greater than 10 mm/s.

The test may be interrupted to allow the stroke of the thrust device to be restarted.

The sample tested has a rectangular shape, with a 3.0 m side (average value - tolerance ± 20%). To allow installation of the system, the test applicant must supply the sample to the laboratory with the dimensions planned for the test or larger, and the laboratory will then carry out the sampling. It must be representative of the product in terms of materials and construction method.

The tests must be performed in the laboratory at ambient temperature, and always in compliance with the standards which regulate the testing procedures for the various materials.

The puncturing test is carried out after fixing the test piece to a rigid frame and it is aimed at measuring the force - movement curve of the central point of the press measured perpendicularly to the plane of the test piece. The test must allow failure of the specimen to be reached. The panel is considered to have failed when it is no longer able to support any increase to the applied force. The puncturing strength of a test piece is therefore defined as the maximum force imparted by the test piece during the test.

DUS 193-2: 2018


Figure A.2 — Geometrical characteristics of the press (dimensions in mm)

The test may also be performed without reaching failure of the panel. In this case, the limit strength which may be certified is equal to the maximum value of the force reached during the test.

The contrast frame is made from a rigid rectangular or square structure, the size of which fully holds the net test piece and the constraint devices (Figure A.3). The distance between the rigid frame and the net test piece, that is, the space holding the constraint devices, must not be greater than 15% of the average side length of the test piece.

The test piece must be centred in the test frame; the width a of the constraining area must be measured along the centreline of each side of the frame.

All the perimeter nets of the test piece are fixed to the frame by means of the constraining devices (e.g. shackles, connecting links, steel ropes or other methods agreed between the testing laboratory and the party requesting the test, and in line with the structural characteristics of the piece to be tested; however, the means of constraint must not interfere with the structural behaviour of the test piece of a size suitable to obtain the planarity of the test piece before starting the test), by using either specific devices (e.g. screw tensioners), or frames with a variable shapes.

The reference plane is defined by the four sides of the frame.

Before starting the test, the test piece must be tensioned until it reaches a condition of “planarity”, which is considered to have been reached when the maximum sag at the centre is less than 20% of the smallest side length of the test piece.

Key

a is constraining Area < 0.15* L

DUS 193-2: 2018


b < 0.2* L [m]

L 3.0 ± 0.2 * 3.0 [m]

1 Net test piece

2 Tensioning devices

3 Rigid frame

Figure B.3 — Section of the frame containing the net test piece and definition of the level conditions

B.2.2 Measurements and observations

The origin of the load – movement diagram is measured from the plane holding the panel constraining devices.

The following measurements must be taken continuously during the test: a. force exercised by the press; b. movement of the press relative to the reference plane.

The force must be measured by class 1 load cells, in accordance with ISO 376.

These measurements must allow the curve characterised by the following parameters to be obtained: a) PBR maximum value of the force reached at failure of the test piece. If failure is not reached, this

must be declared; b) BR movement corresponding to actual failure load reached.

The load – movement curve measured at the centre of the press must be provided for each product, example of graph shown in Figure B4.

Key

X Deformation at the centre, measured perpendicularly to the test piece

Y Load

Figure B.4 — Example of load-movement curve

B.2.3 Test report

The test report must provide the following information:

a) nominal dimensions of test piece and actual dimensions under test conditions;

b) description of instrumentation used and temperature during test;

c) detailed description of the test piece constraining condition, complete with photographic documentation;

DUS 193-2: 2018


d) maximum sag, b reached at the start of the test in those cases in which it may be measured;

e) average dimension, a of the constraining area on the four sides;

f) general description of the failure mode;

g) actual failure load and relative stoke;

h) load - elongation diagram;

i) photographic documentation of the test piece before and after the test;

Key

1 Net

2 Press

3 Perimeter constraining device

Figure B.5 — Example of set up for puncturing test

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Annex B (normative)

B.1 Test method for determination of load transfer of connection elements

B.1.1 General

The aim of this test is to determine the ability of connection elements between mesh panels to transfer the existing transversal tensile load of the mesh. The mesh panels are connected at their traversal edges.

B.1.2 Test specimen

The specimen consists from two individual panels of the same dimensions which are connected together by means of connection elements so the connection itself is located in the middle of completed sample. The chain link wire mesh specimens shall be representative of proper field construction as to materials and geometry. The test specimen shall be ended by the similar way as during the mesh manufacturing with knots according to Table 1.

The width (dimension perpendicular to the direction of loading) of a specimen shall be 1.0 m in length and 1.0 m in width (-10%/+20%). The connection elements need to be installed according to the indications of the supplier.

B.1.3 Test apparatus

The test apparatus consists of a traction machine and rigid steel beams (see Figure B.1) to allow the specimen to be connected to them.

4

3

2

1 5

DUS 193-2: 2018


Figure B.1 — Test arrangement for rhomboid mesh (upper) and quadratic (lower).

Key 1 fixed frame

2 movable beam

3 lateral fixation points

4 longitudinal fixation points

5 connecting elements (for example rope, shackles, clips)

B.1.4 Test procedure

The tests shall be run with the load applied in the transverse direction of mesh/net according to Figure B.1 that the connections of the mesh are tested in.

The specimen is fixed in all opening at all four sides, longitudinal and transverse fixation points. The fixation at all four sides of the sample maintains the specimen shape in transverse/longitudinal direction thus ensuring the uniform load distribution created by the rigid beam.

The fixations shall rotate freely around the axis orthogonal to the plane of tested mesh without any friction to allow the steady displacement of it.

The grips may be left loose until the preload is applied to allow the wires to seat. The load shall initially be taken to a preload of 4 kN. The load Tmax is then applied at a uniform rate between 80 mm/minute to 90 mm/minute. Loading shall then continue uniformly until first fracture or damage of individual connection member or the whole connection occurs.

If any failure of mesh occurs before the individual connection member or the whole connection damage, the test shall not be accepted and the connection shall not be considered to be satisfactory.

B.1.5 Test report

The test report shall contain the following information:

a) Detailed and particular description of test specimen: mesh/net construction, mesh size, component characteristics, connection member characteristics and way of connection;

b) Date of test;

DUS 193-2: 2018


c) Testing institution;

d) Nominal dimensions b and l of test specimen, number of repetitions in both directions and the connection;

e) Initial dimensions of test specimen;

f) Description of testing apparatus;

g) Description of failure mode;

h) Maximum force at failure Tmax and corresponding tensile strength zc = Tmax/b.

DUS 193-2: 2018


Bibliography

[1] US 193:2001, Specification for steel wires and wire products used for fencing

[2] ISO/CD 21124:2017, Chain link steel wire mesh products for civil engineering purposes

DUS 193-2: 2018


Certification marking

Products that conform to Uganda standards may be marked with Uganda National Bureau of Standards (UNBS) Certification Mark shown in the figure below.

The use of the UNBS Certification Mark is governed by the Standards Act, and the Regulations made thereunder. This mark can be used only by those licensed under the certification mark scheme operated by the Uganda National Bureau of Standards and in conjunction with the relevant Uganda Standard. The presence of this mark on a product or in relation to a product is an assurance that the goods comply with the requirements of that standard under a system of supervision, control and testing in accordance with the certification mark scheme of the Uganda National Bureau of Standards. UNBS marked products are continually checked by UNBS for conformity to that standard.

Further particulars of the terms and conditions of licensing may be obtained from the Director, Uganda National Bureau of Standards.

draft uganda standard - world trade organization · 2018. 11. 1. · us iso 7989-2, steel wire and...

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