Anchorage in Concrete Construction, First edition

382 Pages·2006·6.16 MB·English

by  R. Eligehausen

Preface
Modern fastening technology is becoming and the dependence of the behaviour on the
increasingly important in civil and structural loading direction and failure mode are pre-
engineering worldwide. Cast-in-place fasten- sented. The influence of the condition of the
ings, which are placed in the formwork before concrete, non-cracked versus cracked, as well
the concrete is poured, as well as post-installed as the behaviour of fastenings under fire loading
fastening systems, which are installed in hard- and the corrosion behaviour of fasteners is
ened concrete or masonry, have found wide- examined. Additionally, a detailed discussion of
spread use in construction practice. the design of fastenings is provided.
Anchor bolts transfer applied tension loads to This book builds on the volume ‘Befestigungs-
the anchorage material through mechanical technik in Beton- and Mauerwerk’ by Elige-
interlock, friction, bond, or a combination of hausen, Mallée (2000) and translated into the
these mechanisms. Regardless of the load-trans- English by Philip Thrift (Hannover). Extensive
fer mechanism, however, fastening systems rely editing of the translated text was performed by
on the tension strength of the concrete or John Silva. The content in this book, however,
masonry. This fact must be accounted for both has been significantly extended and updated.
in the design of the fastening and the design of
Research in the field of fastening technique
the supporting (or supported) concrete or
from around the world is brought together in
masonry member.
this book. Much of this research was conducted
Every fastening element is designed for optimal
at the Department of Fastening Technology at
performance for a specific application. When a
the University of Stuttgart. The department was
fastening element is used for an application for
founded in the 1970’s by Professor Emeritus
which it was not intended, its performance can
Dr.-Ing. Dr.-Ing. E.h. (mult) Gallus Rehm and
be negatively affected. Knowledge of the
flourished under his oversight until his retire-
behaviour of different fastenings is therefore
ment in 1989. The authors owe him a great deal
necessary to select the proper fastening system
of gratitude.
for a given application and to implement the
design of the fastening correctly. Fastening This book would not have been possible with-
behaviour may be influenced by many parame- out the support of many individuals. We would
ters. Environmental conditions such as chemi- like to thank Mr. M. Hoehler, M.Sc., who con-
cal attack, temperature fluctuation, and fire tributed to section 10 on seismic loading, and
exposure must also be considered. edited the completed manuscript as well as Dr.-
Ing. J. Asmus and Dr.-Ing. T. Sippel for supply-
Although each year millions of anchors are
ing numerous figures. Furthermore we would
installed in concrete and masonry elements on
like to thank Ms. Dipl.-Ing. A. Clauss, Ms.
construction sites around the world, the state of
Dipl.-Ing. Y. Grewin, Ms. Dipl.-Ing. I. Simons,
knowledge about this technology in the practice
Dipl.-Ing. J. Appl, Dipl.-Ing. L. Bezecny, Dipl.-
is often very poor. It is therefore the goal of this
Ing. J. Hofmann, Dipl.-Ing. T. Huer, Dipl.-Ing.
book to present the state of the art relative to
M. Potthoff, Dipl.-Ing. K. Schmid, for their tire-
fastening technology for concrete. Fastening
less effort preparing and editing figures.
products currently available on the market, as
well as their intended areas of application, are
discussed. The fundamentals of their load-bear- Rolf Eligehausen
ing behaviour under short- and long-term load- Rainer Mallée
ing, dynamic loading including seismic loading, John Silva
Contents
1 Introduction ........................................................................................................ 1
1.1 Ahistorical review ............................................................................................... 1
1.2 Requirements for fastenings ................................................................................. 2
1.3 Nature and direction of actions ............................................................................ 2
2 Fastening systems ............................................................................................... 5
2.1 General ................................................................................................................. 5
2.2 Cast-in-place systems ........................................................................................... 5
2.2.1 Lifting inserts ....................................................................................................... 6
2.2.2 Anchor channels ................................................................................................... 7
2.2.3 Headed studs ......................................................................................................... 9
2.2.4 Threaded sleeves .................................................................................................. 9
2.3 Drilled-in systems ................................................................................................. 10
2.3.1 Drilling techniques ............................................................................................... 10
2.3.2 Installation configurations .................................................................................... 10
2.3.3 Drilled-in anchor types ......................................................................................... 11
2.3.3.1 Mechanical expansion anchors ............................................................................. 11
2.3.3.2 Undercut anchors .................................................................................................. 16
2.3.3.3 Bonded anchors .................................................................................................... 19
2.3.3.4 Screw anchors ....................................................................................................... 25
2.3.3.5 Ceiling hangers ..................................................................................................... 25
2.3.3.6 Plastic anchors ...................................................................................................... 27
2.4 Direct installation ................................................................................................. 29
3 Principles ............................................................................................................. 33
3.1 General ................................................................................................................. 33
3.2 Behaviour of concrete in tension .......................................................................... 34
3.3 Failure mechanisms of fastenings ........................................................................ 37
3.3.1 Theoretical studies ................................................................................................ 37
3.3.2 Experimental studies ............................................................................................ 45
3.3.3 Conclusions drawn from theoretical and experimental studies ........................... 50
3.4 Cracked concrete .................................................................................................. 51
3.5 Why anchors may use the tensile strength of concrete ........................................ 54
3.6 Prestressing of anchors ......................................................................................... 55
3.7 Loads on anchors .................................................................................................. 58
3.7.1 Calculation according to elastic theory ................................................................ 58
3.7.1.1 Tension load .......................................................................................................... 58
3.7.1.2 Shear loads ........................................................................................................... 59
3.7.2 Calculation according to non-linear methods ...................................................... 61
3.7.3 Calculation of loads on anchors of anchor channels ............................................ 61
3.7.3.1 Tension loads ........................................................................................................ 61
3.7.3.2 Shear loads ........................................................................................................... 63
VIII Contents
4 Behaviourof headed studs, undercut anchors and metal expansion
anchors in non-cracked and cracked concrete ................................................ 65
4.1 Non-cracked concrete ........................................................................................... 65
4.1.1 Tension load .......................................................................................................... 65
4.1.1.1 Load-displacement behaviour and modes of failure ............................................ 65
4.1.1.2 Failure load associated with steel rupture ............................................................ 68
4.1.1.3 Failure load associated with concrete cone breakout ........................................... 69
4.1.1.4 Failure load for local concrete side blow-out failure ........................................... 93
4.1.1.5 Failure loads associated with pull-out and pull-through failures ......................... 97
4.1.1.6 Failure load associated with splitting of the concrete .......................................... 100
4.1.2 Shear ..................................................................................................................... 103
4.1.2.1 Load-displacement behaviour and modes of failure ............................................ 103
4.1.2.2 Failure load associated with steel rupture ............................................................ 105
4.1.2.3 Failure load associated with pry-out ................................................................... 109
4.1.2.4 Concrete edge failure for a shear load perpendicular to the edge ....................... 112
4.1.2.5 Concrete edge breakout load associated with shear loads oriented
at an angle α< 90°to the edge ............................................................................ 125
4.1.3 Combined tension and shear (oblique loading) .................................................... 128
4.1.3.1 Load-displacement behaviour and modes of failure ............................................ 128
4.1.3.2 Failure load ........................................................................................................... 132
4.1.4 Bending of the baseplate ...................................................................................... 137
4.1.5 Sustained loads ..................................................................................................... 138
4.1.6 Fatigue loading ..................................................................................................... 139
4.2 Cracked concrete .................................................................................................. 142
4.2.1 Tension .................................................................................................................. 143
4.2.1.1 Load-displacement behaviour and modes of failure ............................................ 143
4.2.1.2 Failure load corresponding to steel failure ........................................................... 146
4.2.1.3 Failure load associated with concrete cone breakout ........................................... 146
4.2.1.4 Failure load associated with local blow-out failure ............................................. 154
4.2.1.5 Failure load associated with pull-out/pull-through failure ................................... 155
4.2.1.6 Failure load associated with splitting of the concrete .......................................... 157
4.2.2 Shear ..................................................................................................................... 157
4.2.2.1 Load-displacement behaviour and modes of failure ............................................ 157
4.2.2.2 Failure load associated with steel failure ............................................................. 157
4.2.2.3 Failure load associated with pry-out failure ......................................................... 158
4.2.2.4 Failure load associated with concrete edge breakout ........................................... 158
4.2.3 Combined tension and shear ................................................................................ 159
4.2.3.1 Load-displacement behaviour and modes of failure ............................................ 159
4.2.3.2 Failure load ........................................................................................................... 159
4.2.4 Sustained loads ..................................................................................................... 160
4.2.5 Fatigue loading ..................................................................................................... 162
5 Behaviourof cast-in anchorchannels in non-cracked and
cracked concrete ................................................................................................. 163
5.1 Non-cracked concrete ........................................................................................... 163
5.1.1 Tension .................................................................................................................. 163
5.1.1.1 Load-displacement behaviour and modes of failure ............................................ 163
5.1.1.2 Failure load associated with steel failure ............................................................. 164
5.1.1.3 Failure load associated with concrete cone breakout ........................................... 165
5.1.1.4 Failure load associated with local concrete side blow-out failure ....................... 168
5.1.1.5 Failure load associated with pull-out failure ........................................................ 168
Contents IX
5.1.1.6 Failure load associated with splitting of the concrete .......................................... 169
5.1.2 Shear ..................................................................................................................... 170
5.1.2.1 Load-displacement behaviour and modes of failure ............................................ 170
5.1.2.2 Failure load associated with steel failure ............................................................. 170
5.1.2.3 Failure load associated with pry-out failure ......................................................... 170
5.1.2.4 Failure load associated with concrete edge failure .............................................. 170
5.1.3 Combined tension and shear ................................................................................ 178
5.1.4 Sustained and fatigue loading .............................................................................. 179
5.2 Cracked concrete .................................................................................................. 179
6 Behaviourof bonded anchors in non-cracked and cracked concrete ........... 181
6.1 Non-cracked concrete ........................................................................................... 181
6.1.1 Tension load .......................................................................................................... 181
6.1.1.1 Load-displacement behaviour and modes of failure ............................................ 181
6.1.1.2 Failure load associated with steel failure ............................................................. 184
6.1.1.3 Failure load associated with concrete breakout/pull-out failure .......................... 184
6.1.1.4 Failure load associated with splitting ................................................................... 200
6.1.2 Shear load ............................................................................................................. 200
6.1.2.1 Load-displacement behaviour and modes of failure ............................................ 200
6.1.2.2 Failure load associated with steel failure ............................................................. 200
6.1.2.3 Failure load associated with pry-out failure ......................................................... 200
6.1.2.4 Failure load associated with concrete edge breakout ........................................... 200
6.1.3 Combined tension and shear load ........................................................................ 200
6.1.4 Sustained and fatigue loading .............................................................................. 200
6.1.5 Environmental factors .......................................................................................... 202
6.2 Cracked concrete .................................................................................................. 204
6.2.1 Tension load .......................................................................................................... 204
6.2.1.1 Load-displacement behaviour and modes of failure ............................................ 204
6.2.1.2 Failure load corresponding to steel failure ........................................................... 205
6.2.1.3 Failure load corresponding to pull-out failure ..................................................... 205
6.2.1.4 Failure loads corresponding to concrete cone failure and splitting
of the concrete ...................................................................................................... 206
6.2.2 Shear load ............................................................................................................. 207
6.2.3 Combined tension and shear load ........................................................................ 207
6.2.4 Sustained and fatigue loads .................................................................................. 208
6.2.5 Environmental factors .......................................................................................... 208
6.3 Bonded undercut anchors and bonded expansion anchors .................................. 208
6.3.1 Non-cracked concrete ........................................................................................... 208
6.3.2 Cracked concrete .................................................................................................. 208
6.3.2.1 Tension load .......................................................................................................... 208
6.3.2.2 Shear and combined tension and shear load ........................................................ 210
7 Behaviourof plastic anchors in non-cracked and cracked concrete ............. 211
7.1 Non-cracked concrete ........................................................................................... 211
7.1.1 Tension load .......................................................................................................... 211
7.1.2 Shear and combined tension and shear load ........................................................ 215
7.1.3 Long-term behaviour ............................................................................................ 215
7.2 Cracked concrete .................................................................................................. 220
7.2.1 Tension load .......................................................................................................... 220
7.2.2 Shear and combined tension and shear load ........................................................ 222
7.2.3 Long-term behaviour ............................................................................................ 222
X Contents
8 Behaviourof poweractuated fasteners in non-cracked and
cracked concrete ................................................................................................. 223
8.1 Non-cracked concrete ........................................................................................... 223
8.1.1 Tension load .......................................................................................................... 223
8.1.2 Shear and combined tension and shear load ........................................................ 224
8.1.3 Sustained and repetitive loading .......................................................................... 224
8.2 Cracked concrete .................................................................................................. 225
8.2.1 Tension load .......................................................................................................... 225
8.2.2 Shear and combined tension and shear load ........................................................ 226
9 Behaviourof screw anchors in non-cracked and cracked concrete .............. 227
9.1 Installation ............................................................................................................ 227
9.2 Non-cracked concrete ........................................................................................... 231
9.2.1 Tension load .......................................................................................................... 231
9.2.1.1 Load-displacement behaviour and failure modes ................................................ 231
9.2.1.2 Failure loads associated with steel failure ............................................................ 231
9.2.1.3 Failure loads associated with pull-out failure ...................................................... 231
9.2.1.4 Failure loads associated with concrete cone failure ............................................. 231
9.2.2 Shear load ............................................................................................................. 233
9.2.2.1 Load-displacement behaviour and modes of failure ............................................ 233
9.2.2.2 Failure load associated with steel failure ............................................................. 233
9.2.2.3 Failure load associated with pry-out failure ......................................................... 233
9.2.2.4 Failure load associated with concrete edge breakout ........................................... 233
9.2.3 Combined tension and shear load ........................................................................ 234
9.2.4 Sustained and fatigue loads .................................................................................. 234
9.3 Cracked concrete .................................................................................................. 234
9.3.1 Tension load .......................................................................................................... 234
9.3.2 Shear load and combined tension and shear load ................................................ 235
9.3.3 Sustained and fatigue loads .................................................................................. 235
10 Behaviour of anchors under seismic loading ....................................................... 237
10.1 Anchor applications .............................................................................................. 237
10.2 Seismic actions ..................................................................................................... 238
10.3 Assumptions regarding the condition of the concrete .......................................... 239
10.4 Behaviour of anchors under seismic conditions .................................................. 240
10.4.1 Tension cycling ..................................................................................................... 241
10.4.2 Shear cycling ........................................................................................................ 242
10.4.3 Combined tension and shear cycling .................................................................. 245
10.4.4 Loading rate .......................................................................................................... 245
10.4.5 Load cycle sequence ............................................................................................. 246
10.4.6 Crack cycling ........................................................................................................ 247
11 Behaviourof anchors in fire .............................................................................. 249
12 Corrosion of anchors .......................................................................................... 255
Contents XI
13 Influence of fastenings on the capacity of components in
which they are installed ..................................................................................... 259
14 Design of fastenings ............................................................................................ 265
14.1 General ................................................................................................................. 265
14.2 Verifying the suitability of an anchor system ...................................................... 266
14.3 Design of fastenings with post-installed metal expansion, undercut and
bonded expansion anchors according to the EOTAGuideline ............................ 267
14.3.1 General ................................................................................................................. 267
14.3.2 Scope .................................................................................................................... 268
14.3.3 Design concept ..................................................................................................... 269
14.3.3.1 Analysis for the ultimate limit state ..................................................................... 269
14.3.3.2 Analysis for the serviceability limit state ............................................................. 270
14.3.4 Forces on anchors ................................................................................................. 271
14.3.5 Characteristic resistances ..................................................................................... 274
14.3.5.1 Tension resistances ............................................................................................... 275
14.3.5.2 Shear resistances ................................................................................................... 277
14.3.5.3 Combined tension and shear ................................................................................ 280
14.3.6 Serviceability limit state ....................................................................................... 281
14.3.6.1 Anchor displacements .......................................................................................... 281
14.3.6.2 Shear load with changing sign ............................................................................. 281
14.3.7 Additional analyses for ensuring the characteristic resistance of
concrete member .................................................................................................. 281
14.3.7.1 General ................................................................................................................. 281
14.3.7.2 Shear resistance of the concrete member ............................................................. 281
14.3.7.3 Resistance to splitting forces ................................................................................ 283
14.4 Design of fastenings according to the CEN Technical Specification .................. 283
14.4.1 General ................................................................................................................. 283
14.4.2 Scope .................................................................................................................... 283
14.4.3 Basis of design .................................................................................................... 285
14.4.4 Partial safety factors ............................................................................................. 286
14.4.4.1 Static actions, indirect actions and fatigue actions .............................................. 286
14.4.4.2 Resistances ........................................................................................................... 286
14.4.4.2.1 Ultimate limit state (static loading) and seismic loading ..................................... 286
14.4.4.2.2 Limit state of fatigue ............................................................................................ 287
14.4.4.2.3 Serviceability limit state ....................................................................................... 287
14.4.5 Forces acting on fasteners .................................................................................... 287
14.4.5.1 Tension loads ........................................................................................................ 287
14.4.5.2 Shear loads ........................................................................................................... 287
14.4.5.2.1 Distribution of loads ............................................................................................. 287
14.4.5.2.2 Shear loads without lever arm .............................................................................. 288
14.4.5.2.3 Shear loads with lever arm ................................................................................... 289
14.4.6 Design of headed fasteners ................................................................................... 289
14.4.6.1 Determination of action effects ............................................................................ 289
14.4.6.2 Verification of ultimate limit state by elastic analysis ......................................... 290
14.4.6.2.1 Tension loads ........................................................................................................ 290
14.4.6.2.2 Shear loads ........................................................................................................... 293
14.4.6.2.3 Combined tension and shear loads ....................................................................... 302
14.4.7 Design of anchor channels ................................................................................... 302
14.4.7.1 Derivation of forces acting on the anchors of the anchor channel ...................... 303
14.4.7.1.1 Tension loads ........................................................................................................ 303
XII Contents
14.4.7.1.2 Shear loads ........................................................................................................... 304
14.4.7.2 Tension forces in the supplementary reinforcement ............................................ 304
14.4.7.2.1 Tension loads ........................................................................................................ 304
14.4.7.2.2 Shear loads ........................................................................................................... 304
14.4.7.3 Verification of ultimate limit state by elastic analysis ......................................... 305
14.4.7.3.1 Tension loads ........................................................................................................ 305
14.4.7.3.2 Shear loads ........................................................................................................... 309
14.4.7.3.3 Combined tension and shear loads ....................................................................... 313
14.4.7.3.3.1 Anchor channels without supplementary reinforcement ...................................... 313
14.4.7.3.3.2 Anchor channels with supplementary reinforcement ........................................... 313
14.4.8 Design of post-installed fasteners – mechanical systems .................................... 313
14.4.8.1 Scope .................................................................................................................... 313
14.4.8.2 Determination of action effects ............................................................................ 313
14.4.8.3 Verification of ultimate limit state by elastic analysis ......................................... 313
14.4.8.3.1 General ................................................................................................................. 313
14.4.8.3.2 Tension loads ........................................................................................................ 314
14.4.8.3.3 Shear loads ........................................................................................................... 314
14.4.8.3.4 Combined tension and shear loads ....................................................................... 315
14.4.9 Design of post-installed fasteners – chemical systems ........................................ 315
14.4.9.1 Tension resistances ............................................................................................... 315
14.4.9.2 Shear loads ........................................................................................................... 316
14.4.9.3 Combined tension and shear loads ....................................................................... 316
14.4.10 Fatigue loads ......................................................................................................... 316
14.4.11 Seismic loads ........................................................................................................ 319
14.4.11.1 General ................................................................................................................. 319
14.4.11.2 Actions .................................................................................................................. 320
14.4.11.3 Resistances ........................................................................................................... 322
14.4.12 Verification of serviceability limit state ............................................................... 322
14.4.13 Fire ........................................................................................................................ 323
14.4.13.1 General ................................................................................................................. 323
14.4.13.2 Partial safety factors ............................................................................................. 323
14.4.13.3 Resistance ............................................................................................................. 323
14.4.13.3.1 Tension loading .................................................................................................... 323
14.4.13.3.2 Shear loading ........................................................................................................ 324
14.4.13.3.3 Combined tension and shear loading ................................................................... 325
14.4.14 Plastic design of fastenings with headed fasteners and post-installed fasteners ..... 325
14.4.14.1 Field of application ............................................................................................... 325
14.4.14.2 Loads on fastenings .............................................................................................. 326
14.4.14.3 Design of fastenings ............................................................................................. 328
14.4.14.3.1 Partial safety factors ............................................................................................. 328
14.4.14.3.2 Resistance to tension load .................................................................................... 328
14.4.14.3.3 Resistance to shear load ....................................................................................... 329
14.4.14.3.4 Resistance to combined tension and shear load ................................................... 329
14.5 Design of fastenings with cast-in and post-installed metal anchors
according to ACI 318-05 Appendix D ................................................................. 330
14.5.1 General ................................................................................................................. 330
14.5.2 Scope .................................................................................................................... 330
14.5.3 Design concept ..................................................................................................... 331
14.5.3.1 Analysis for the ultimate limit state ..................................................................... 331
14.5.3.2 Serviceability limit state ....................................................................................... 333
14.5.4 Forces on anchors ................................................................................................. 333
Contents XIII
14.5.5 Characteristic resistances ..................................................................................... 333
14.5.5.1 General ................................................................................................................. 333
14.5.5.2 Tension resistance ................................................................................................. 333
14.5.5.3 Shear resistance .................................................................................................... 336
14.5.5.4 Combined tension and shear ................................................................................ 339
14.5.6 Required edge distances, spacings and member thicknesses to
preclude splitting failure ....................................................................................... 339
14.5.7 Resistance where load cases include seismic forces ............................................ 340
14.5.8 Provisions of ACI 349-01 Appendix B ................................................................ 340
14.5.8.1 Scope .................................................................................................................... 340
14.5.8.2 Ductile design requirements ................................................................................. 340
14.5.8.3 Baseplate design ................................................................................................... 341
References ............................................................................................................................... 343
Subject Index ............................................................................................................................ 371
Anchorage in Concrete Construction, First edition
by R. Eligehausen, R. Mallée and J. F. Silva
© 2006 Ernst & Sohn GmbH & Co. KG. Published 2006 Ernst & Sohn GmbH & Co. KG.
1 Introduction
1.1 A historical review The mortar used in masonry assemblies can be
regarded as the oldest type of connection mate-
The task of connecting building components is
rial. In fact, the hewn dovetails, cast metal
as old as building itself. Throughout history, the
joints and embedded metal studs or sleeves his-
job has been handled in different ways depend-
torically employed in stone masonry may be
ing on the building material, the structural sys-
considered to be the predecessors of today’s
tem and the particular requirements of the con-
modern fastening technology. Today, these
struction.
methods have been largely replaced by plastic
In wood construction traditional joinery began and/or metal elements of sophisticated design
with timbers bound with tough natural fibres inserted into pre-drilled holes and secured via
and developed into various types of interlock- friction, mechanical interlock, chemical bond,
ing, screwed and doweled joints, glued and fin- or a combination thereof. Today there are sys-
ger joints as well as embedded steel plates and tems available that are suitable for practically
ring connectors. any type of masonry.
Steel construction, a comparatively ‘young’dis- Concrete and reinforced concrete construction
cipline, employs connection techniques ranging initially borrowed fastening techniques from
from cast-iron fittings to rivets, bolts and weld- other building trades, either unchanged or only
ing, whereby only bolting and welding are in slightly modified. Wood lathe placed in the
common use today. formwork was anchored in the concrete via pre-
In concrete and masonry construction, various driven nails and served as an attachment point
means of anchoring are in regular use for the entire range of building systems, as well
(Fig. 1.1). as for suspended ceilings. Later, threaded
Fig. 1.1 Fastening methods in concrete
2 1 Introduction
sleeves, anchor channels and headed studs 1.2 Requirements for fastenings
welded to steel plates were employed, these
Fastenings must be designed in such a way that
being secured inside the formwork and cast into
they do the job for which they are intended, are
the concrete.
durable and robust, and exhibit sufficient load-
These so-called “cast-in-place” techniques were carrying and deformation capacity. Fastenings
later rivalled by systems designed to be for less critical applications, e.g. securing light-
installed after the concrete had cured. The evo- weight duct, lighting, and wiring, can be
lution of drilling technology from chisels to selected on the basis of the user’s experience
rotary-percussion tools and the more recent and do not usually require analysis or structural
development of diamond core drilling has review (outside areas of seismic hazard). On the
opened up new opportunities for the field of other hand, fastenings that are relevant to life
post-installed anchoring technology. safety, i.e. whose failure could pose a hazard to
life or result in significant economic loss, must
For minor loads, the ubiquitous plastic anchor, generally be selected on the basis of structural
successor to hemp and lead plugs, has all but considerations and are typically designed and
replaced other techniques. To cope with higher detailed by a structural engineer. The design
loads, various types of metal expansion anchors establishes whether the requirements of the ser-
have been developed that employ, in principle, viceability and ultimate limit states are met. The
the same functional principles but with varying serviceability limit state includes requirements
construction details and attendant variations in for limiting deformation, and requirements on
installation and application conditions. durability (corrosion, chemical resistance). At
the ultimate limit state it must be proven that the
Bonded anchors, in which a steel rod is grouted
design value of the actions does not exceed the
into a pre-drilled hole, continue to be frequently
design value of the fastening resistance. Analy-
used. Representing the latest stages in this chain
ses of the serviceability and ultimate limit states
of development are undercut anchors, hybrid
generally make a distinction between the type
systems employing bond, friction and/or
and direction of the load. Section 1.3 deals with
mechanical interlock, and second-generation
loads acting on connections and section 3.7
self-tapping screws.
with the distribution of these loads to the fas-
Parallel with the development of anchors for teners. The capacities of the fastenings are
pre-drilled holes, the technology of high- explained in relation to the type of fastener and
strength steel nails or studs driven into steel and type of base material as well as failure mode in
concrete by an explosive or pneumatic energy sections 4 to 9. The behaviour of fasteners
source (so-called power-actuated fastening) has under seismic excitations and under fire is dealt
seen growing use over the past four decades. with in sections 10 and 11 respectively. Corro-
These systems serve to simplify the attachment sion and corrosion protection is discussed in
of piping systems, lightweight suspended ceil- section 12 and the influence of fastenings on the
ings, etc., and are also widely employed for the capacity of concrete members in which they are
attachment of metal deck to steel framing. installed is explained in section 13. Require-
ments on the suitability of fasteners for the
Clearly, post-installed fastening in concrete and application in question and the design of fasten-
masonry is a relatively young discipline, mean- ings are discussed in section 14.
ing that the state of the art is generally in a state
of flux. Consequently, these systems typically
1.3 Nature and direction of actions
cannot be regulated via prescriptive standards,
as is done, say, with high-strength structural Actions (loads) can be classified according to
bolts. Consequently, in the member states of the the frequency of their occurrence and their
European Community, the U.S. and other coun- duration. In addition, we can make a distinction
tries the design and installation of post-installed as to whether or not inertial forces are involved.
fastenings is usually carried out in accordance Table 1.1 provides an overview of various
with product-specific approvals. actions. Dynamic forces arise in cases of