Advisory Desk / Codes and Standards
NSC 31
Nov/Dec 18
AD 424:
Shear stud length
SCI has been advised that shear
studs which are shorter than usual
have been placed on the market in
the UK, and this AD warns against
using them unless the length has
been reflected in the design, and
unless the studs meet the necessary
material specification.
AD 380 indicates that a stud that
starts with a manufactured length
of 105 mm would typically have
a length after welding (LAW) of
100 mm when welded directly to
a beam flange and 95 mm when
welded through decking. The studs
are identified as nominally 100 mm
BS EN PUBLICATIONS
BS EN ISO 15626:2018
Non-destructive testing of welds.
Time-of-flight diffraction technique
(TOFD). Acceptance levels
Supersedes BS EN ISO 15626:2013
studs. AD 380 also indicates that
studs of diameter d = 19 mm and a
nominal length of 100 mm may be
deemed to satisfy the requirement
that a stud extends at least 2d
above the height of the decking,
when that height is 60 mm. UK
practice in composite construction
for buildings generally involves
the use of through deck welded
shear studs. Tests have shown that
through deck welded studs of 100
mm nominal length, with 60 mm
decking, perform satisfactorily.
A complication is that studs
identified as nominally 100 mm
BS IMPLEMENTATIONS
BS ISO 1835:2018
Round steel short link chains for
lifting purposes. Medium tolerance
sling chains. Grade 4, stainless steel
No current standard is superseded
PUBLISHED DOCUMENTS
PD CEN ISO/TR 20173:2018
Welding. Grouping systems for
materials. American materials.
Supersedes PD CEN ISO/TR 20173:2009
long have actual lengths “out of the
box” which differ from manufacturer
to manufacturer. It is understood
that the shorter studs referred to in
the opening paragraph are 90 mm
before welding, so are likely to be
less than 85 mm LAW when welded
through decking. Clearly they
should not simply be substituted for
nominal 100 mm studs unless the
design is verified with the shorter
length.
All shear studs should conform
to EN ISO 13918, as noted in the
National Structural Steelwork
Specification (NSSS). Composite
BRITISH STANDARDS REVIEWED
AND CONFIRMED
BS EN ISO 19232-1:2013
Non-destructive testing.
Image quality of radiographs.
Determination of the image quality
value using wire-type image quality
indicators
BS ISO 14346:2013
Static design procedure for
welded hollow-section joints.
Recommendations
BRITISH STANDARDS
WITHDRAWN
BS EN ISO 15626:2013
Non-destructive testing of welds.
Time-of-flight diffraction technique
(TOFD). Acceptance levels
Superseded by BS EN ISO 15626:2018
PD CEN ISO/TR 20173:2009
Welding. Grouping systems for
materials. American materials
Superseded by PD CEN ISO/TR
20173:2018
New and revised codes & standards
From BSI Updates October 2018
beam design generally assumes a
certain level of slip between the
steel and concrete so the studs
must be ductile, regardless of the
fact that failure is normally in the
concrete (at least for the grades
of materials typically found in
buildings). Annex B of BS EN 1994-1
describes the stud test arrangement
to demonstrate ductility.
Contact: Eleftherios
Aggelopoulos
Tel: 01344 636525
Email: advisory@steel-sci.com
the box was in one position, ie
with the web horizontal, thus saving
a part turn.
Additionally, the edges of the bottom
flanges were bevelled in line
with the web to avoid a shadow
line on the bridge.
Non-destructive testing
All plates were ultrasonically
tested in the works and shop
butt welds in both top and bottom
flanges were subject to 100
per cent radiographic testing. In
addition, coupon plates were provided
for further testing of these
butt welds, the tests being: one
tensile, one normal bend, one reverse
bend for each flange, with
three charpy ‘V’-notch tests for the
tension flange. The latter were
carried out, with the notch in the
weld metal vertical to the plate
surface at -15°C and the requirements
for NDII steel to BS.2762
in this respect, ie average value of
20 ft lb for three specimens with
no individual specimen breaking
under less that 15 ft lb, were fully
met. The other mechanical tests
were conducted in accordance
with BS.709.
All inside fillet welds on tension
flanges were tested for cracks
using K-07 Magnaflux simplified
crack detector with Ardrox No
800-2 black magnetic particle inspection,
kerosene based.
Tests for welding procedures
All welders were required to pass
the appropriate tests specified in
BS.2645 according to the degree
of skill necessitated by the procedures,
manual, semi-automatic, or
automatic, on which they were to
be employed.
The Irwell Valley Bridge was
designed by Lancashire County
Council and the contract was
placed by the MoT North Western
Road Construction Unit (Director,
Mr James Drake, CBE).
/Design
/Advisory_Desk_Notes
/Composite_construction
/Welding#Drawn_arc_stud_welding.2C_process_783
/Welding
/Steel_construction_products#Decking_for_floors
/Steelwork_specification#The_National_Structural_Steelwork_Specification_for_Building_Construction
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