Best practice specification, design and
installation for post-installed anchors in
safety-critical applications
Dr. Jessey Lee
Dr. David Heath
Prof. Emad Gad
www.aefac.org.au
1
KEY TAKE-AWAY POINTS
TS 101 is for safety-critical applications only
Concrete is assumed to be cracked unless proven otherwise
Not all chemical anchors are the same, particularly under sustained
loading applications – not all chemicals are suitable for sustained
loading applications.
• For e.g. in uncracked concrete, a polyester may have bond
strength in the range of 5 – 9 MPa while an epoxy may have
bond strength in the range of 10 – 15 MPa
For quality assurance of safety critical applications, require:
• Product prequalification
• Design as per TS 101
• Installation by qualified installers 2
OUTLINE
Australian Engineered Fasteners and Anchors Council
Anchor types and safety-critical applications
Prequalification
Design methodology
Installation
Case study
Summary & acknowledgements
3
AUSTRALIAN
ENGINEERED
FASTENERS &
ANCHORS
COUNCIL
AEFAC FOUNDING BOARD MEMBERS
AEFAC SUPPORTING MEMBERS
5
AUSTRALIAN ENGINEERED FASTENERS AND ANCHORS COUNCIL
Guidelines for the specification Training & certification for
of anchors installers of anchors
For Designers For Contractors
Minimum performance & Guideline for field testing &
standard specification AEFAC certification of anchors
For Manufacturers For Field Engineers
Research & Development
For anchor industry
6
SAFETY-CRITICAL
APPLICATIONS &
TYPES OF ANCHORS
7
Fastening for safety-critical applications
A fastening whose failure may result in collapse or partial
collapse of the structure, endanger human life and/or cause
considerable economic loss.
8
APPLICATIONS Nonstructural
• Facades
• Suspended ceilings
• Heating & ventilation
• Pipelines
• Mechanical equip.
• Etc.
Structural
• Structural connections
• Strengthening
Eligehausen (University of Stuttgart)
9
Types of anchors:
Post installed anchors Cast in anchors
10
Post-installed applications: steel to concrete connections
Post-installed applications: concrete to concrete connections
CAST IN PLACE ANCHORS
13
WHAT CAN GO WRONG WITH ANCHORS?
Street awning collapse in Queensland
1 fatality, 5 injuries
Source: Workplace Health and Safety Queensland
14
WHAT CAN GO WRONG WITH ANCHORS?
Boston
Big Dig
Tunnel,
2006
Source: NTSB (2007) Highway Accident Report,
“Ceiling collapse in the Interstate 90 Connector
Tunnel, Boston, Massachusetts, July 10, 2006”
15
WHAT CAN GO WRONG WITH ANCHORS?
Typical chemical anchor
and roof hanger plate
assembly.
Photograph taken following incident showing roof Three of the 20 failed
hangers pulled away from tunnel roof. anchors taken from
Source: Brady, S., “Interstate 90 Connector Tunnel the site of the
ceiling collapse” The Structural Engineer, April 2013 incident illustrating
defects.
Source: NTSB (2007) Highway Accident
Report, “Ceiling collapse in the Interstate 90
Boston Big Dig Tunnel, 2006 Connector Tunnel, Boston, Massachusetts,
July 10, 2006” 16
SAFETY-CRITICAL APPLICATIONS
Three critical elements to achieve quality assurance
1. PREQUALIFICATION Products independently assessed to be “fit
for purpose”
2. DESIGN Rigorous assessment to design for critical
mode of failure
3. INSTALLATION Informed and competent installer with appropriate
supervision and experience
17
PREQUALIFICATION
SA TS101:2015 APPENDIX B
PREQUALIFICATION
Identification tests – is product fully traceable and does it
meet product specifications?
Suitability tests – is the product suitable for its intended
application?
Admissible service condition tests – will the product perform
for its service life?
19
PREQUALIFICATION IN TS101
Two approaches for prequalification:
1. Testing and assessment in accordance with Appendix B
Testing in accordance with ETAG001 parts 1 to 5 or EAD as
applicable and assessment as outlined in Appendix B
Or
2. European Technical Assessment (ETA)
A current ETA satisfies the relevant testing and assessment
requirements as outlined in Appendix B
20
SAFETY-CRITICAL ANCHORS
Three critical elements to achieve quality assurance
1. PREQUALIFICATION Products independently assessed to be “fit
for purpose”
2. DESIGN Rigorous assessment to design for critical
mode of failure
3. INSTALLATION Informed and competent installer with appropriate
supervision and experience
21
SA TS 101—2015
“DESIGN OF POST-INSTALLED
AND CAST-IN FASTENINGS FOR
USE IN CONCRETE”
22
SA TS 101—2015
Deemed-to-satisfy provisions
Primary reference in 2016 NCC:
NCC Volume One – Clause B1.4(b)(iii)
NCC Volume Two – Clause 3.11.6(f)(iii)
23
SA TS 101—2015
2016 NCC
SA TS 101 ALTERNATIVE
(Deem-to-Satisfy) SOLUTION
AEFAC Installer
PREQUALIFICATION
Certification Program
(APPENDIX B)
(RECOMMENDED)
TEST & ASSESS
(APPENDIX B) ETA
(ETAG & EAD)
24
SA TS 101—2015
Overview
Based on European guidelines
Compatible with products prequalified through Appendix B
Scope – safety-critical fasteners
Post-installed Cast-in
Mechanical anchors Anchor channel
Chemical anchors
25
SA TS 101—2015
Exclusions
Design for exposure to fire, durability and seismic actions
Design of fixtures
Design of fasteners for lifting, transport and erection (brace inserts, lifting
inserts, etc.)
Headed fasteners
Ferrules
Reinforcement for development length considerations
Headed reinforcement
Anchorage for prestressing strands
26
SA TS 101—2015
Determination of forces acting on fasteners
Load sharing among fasteners
Eccentricity in a fastener group
Influence of edges
Influence of a lever arm
Influence of fixture plate
Load resisted by supplementary
reinforcement (if present)
27
SA TS 101—2015
Permissible configurations of fastenings:
a) Configurations of fasteners close to an edge (ci < max(10hef, 60dnom)), tension only
b) Configurations of fasteners remote from edges (ci ≥ max(10hef, 60dnom)), all load directions
c) Configurations of fasteners close
to an edge (ci < max(10hef,
60dnom)), all load directions
28
TS 101: CRACKED CONCRETE
• Limited to maximum crack width of 0.3
mm
• Concrete assumed to be CRACKED in
design unless proven otherwise.
• Note: Not all products can be used in
cracked concrete!!
SA TS 101: FAQ (www.aefac.org.au) 29
SA TS 101—2015
ANCHOR CONCRETE PULL-OUT CONE & PULL- SPLITTING BLOW-OUT
TENSION
FRACTURE CONE OUT
SUPPLEMENTARY SUPPLEMENTARY
ANCHOR CHANNEL LIP CHANNEL ANCHOR/ REINFORCEMENT – REINFORCEMENT30–
BOLT FLEXURE CHANNEL FRACTURE ANCHORAGE FAILURE
FRACTURE CONNECTION
30
SA TS 101—2015
FRACTURE (NO BENDING (LEVER EDGE PRYOUT (a) FRACTURE (b) ANCHORAGE
LEVER ARM) ARM) FAILURE FAILURE SUPPLEMENTARY REO.
SHEAR
31
FRACTURE BENDING ANCHOR ANCHOR/ LIP FLEXURE EDGE PRYOUT
(NO LEVER (LEVER FRACTURE CHANNEL FAILURE FAILURE
ARM) ARM) CONNECT.
SUPPLEMENTARY REO.
31
SA TS 101—2015: SHEAR LOADS DISTRIBUTION CLOSE TO AN EDGE
Shear load perpendicular to edge (only 2
Shear load parallel to edge
fasteners closest to edge considered)
32
SA TS 101—2015
Steel failure – bolt failure
Steel failure – anchor channel modes
Other failure modes
COMBINED
Supplementary reinforcement
33
SA TS 101—2015 : DESIGN METHODOLOGY
Example: Concrete cone failure mode (tension)
Ac , N
N Rk ,c N Rk
0
0
,c
s , N re, N ec , N M , N Inverted rectilinear
Ac , N pyramid
Cross-section
,c characteristic concrete cone strength (no spacing effects, edge effects,
0
N Rk
etc.
k9 f 'c hef
1.5
Ac , N
0 adjustment for effects of fastener spacing and edge effects (can the full
A inverted rectilinear pyramid cone form?)
c, N
s, N factor accounting for disturbance of stresses in concrete due to an edge
re, N factor accounting for a dense layer of reinforcement in concrete
Plan view
ec, N factor accounting for different tension loads on fasteners in a group subjected
to eccentric loading
M , N factor accounting for the influence of a compression force between the fixture
and concrete when a bending moment is present
NB: Still need to consider other potential modes of failure
to determine decisive failure mode!
SA TS 101—2015 : DESIGN METHODOLOGY
Software
Freely available from reputable
manufacturers
Rapidly solve complex designs
(minutes vs. hours/days!)
Include prequalified products (i.e.
ETA)
Compatible with TS 101 (with
conversion)
SA TS 101—2015: DESIGN SOFTWARE
List of software that design to SA TS 101 / ETAG
• Ramset – iExpertTM
• Hilti - PROFIS Free download
• Wurth – Technical Software on website
• Powers – Design Assist
• Simpson Strong Tie – Anchor Designer
36
SA TS 101—2015: FAO
Refer to AEFAC’s website www.aefac.org.au
for FREQUENTLY ASKED QUESTIONS on SA TS
101
37
SAFETY-CRITICAL ANCHORS
Three critical elements to achieve quality assurance
1. PREQUALIFICATION Products independently assessed to be “fit
for purpose”
2. DESIGN Rigorous assessment to design for critical
mode of failure
3. INSTALLATION Informed and competent installer with appropriate
supervision and experience
38
AEFAC
INSTALLER
CERTIFICATION
PROGRAM
39
AEFAC INSTALLER CERTIFICATION PROGRAM
“The best product is only as good as its installation”
Correct installation is imperative to ensure the designer’s intent is met
Until now, performed on an ad-hoc basis – job dependent, product specific
Reasonable errors acceptable, gross errors dangerous
Combination of appropriate training and supervision critical
Clear need for a program to provide:
Written and practical test
How to correctly drill
How to correctly prepare a hole
Understanding anchor systems
Understanding risks of errors
40
INSTALLER CERTIFICATION PROGRAM
41
AEFAC INSTALLER CERTIFICATION PROGRAM
Importance of hole cleanliness
Drill dust will prevent proper bonding -> Strength reduction!
Well-cleaned Poorly cleaned
Courtesy of IWB, University of Stuttgart
42
AEFAC INSTALLER CERTIFICATION PROGRAM
Sensitivity to cleaning method
Drill dust will prevent proper bonding -> Strength reduction!
120 Method of hole
cleaning
100
1 – 2xblowing,
Bond Strength, %
80 2xbrushing,
2xblowing
60
2 – 1xblowing,
40 1xbrushing
1xblowing
20 3 – 2xblowing
0 4 – No cleaning
1 2 3 4 (drilling machine
retracted 3 times)
Method of Hole Cleaning
43
AEFAC INSTALLER CERTIFICATION PROGRAM
Written examination
Training
Face to face training,
Installer Training Manual Practical examination
Part 1: Vertical down installation
Part 2: Overhead injection
Certification awarded
*This program is based on the US ACI-
CRSI Adhesive Anchor Installer
Recertification period
Program modified for Australian Initial: Three years
practice Additional: Every five years
44
AEFAC INSTALLER CERTIFICATION PROGRAM
Important note:
“By completing certification, you have demonstrated that
you understood the risks involved in poor installation
practices”
Abide to the AEFAC Installer Code of Conduct
Failure to comply after certification awarded
Certification status revoked
Potential legal implications!
Certified Installer Card awarded &
registration on AEFAC’s website 45
AEFAC INSTALLER CERTIFICATION PROGRAM
46
AEFAC INSTALLER CERTIFICATION PROGRAM
47
INSTALLER CERTIFICATION PROGRAM – OVERHEAD INJECTION
48
INSTALLER CERTIFICATION PROGRAM – OVERHEAD INJECTION
49
But I’ve been doing it this way for years!
AEFAC TECHNICAL
NOTE – ENGINEERING
GENERAL NOTES
HTTP://WWW.AEFAC.ORG.AU/D
OCUMENTS/AEFAC-TN-ENG-
GEN-NOTES.PDF
51
AEFAC TECHNICAL
NOTE – ENGINEERING
GENERAL NOTES
www.aefac.org.au/resources
52
AEFAC ENGINEERING GENERAL NOTES
Proposed notes for contract drawings
53
SUMMARY & ACKNOWLEDGEMENTS
Anchor industry is safety-critical.
Anchor failures should not happen – they do!
AEFAC has created a body of knowledge and expertise to
introduce governance to the Australian anchor industry
Satisfactory anchor performance is achieved from: i)
appropriate product prequalification, ii) robust design, and iii)
correct installation.
TS 101 provides a consistent and robust approach to anchor
design based on best practice
The AEFAC Installer Certification Program has been
developed to equip installers with the skill to ensure that
anchors are installed as intended
54
SUMMARY & ACKNOWLEDGEMENTS
Website
Overview of AEFAC
AEFAC members
Education events
Technical Notes
Sample Specifications
Installer Certification
TS 101: FAQ
Links to resources
www.aefac.org.au
55
SUMMARY & ACKNOWLEDGEMENTS
Founding Board Members
Supporting Members
56
