ISO 5091-4:2023

INTERNATIONAL ISO
STANDARD 5091-4
First edition
2023-07
Structural intervention of
existing concrete structures using
cementitious materials —
Part 4:
Jacketing
Intervention structurelle sur les structures en béton existantes
utilisant des matériaux cimentaires —
Partie 4: Chemisage
Reference number
© ISO 2023
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
Contents Page
Foreword .v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Investigation of existing structure.2
4.1 General . 2
4.2 Investigation . 2
4.2.1 Investigation using documents, records . 2
4.2.2 On-site investigation . 3
5 Intervention design. 3
5.1 General . 3
5.2 Structural plan . 3
5.3 Structural details . 3
6 Materials . 4
6.1 General . 4
6.2 Materials in existing structure . 4
6.3 Materials used in repairing or strengthening parts . 4
6.3.1 General . 4
6.3.2 Cementitious materials . 5
6.3.3 Reinforcing materials . 6
6.3.4 Bonding products . 6
6.3.5 Filling materials . 7
6.4 Characteristic values and design values of materials . 7
6.4.1 General . 7
6.4.2 Cementitious materials . 7
6.4.3 Reinforcing materials . 7
6.4.4 Bonding products . 7
7 Actions . 7
7.1 General . 7
7.2 Actions for intervention design . 7
8 Performance verification for repaired or strengthened structure .7
8.1 General . 7
8.2 Calculation of response values . 8
8.2.1 General . 8
8.2.2 Modelling of structure. 8
8.2.3 Structural analysis . 8
8.2.4 Calculation of response . 8
8.3 Durability verification . 8
8.4 Safety verification . 8
8.4.1 General . 8
8.4.2 Verification related to failure . 9
8.5 Serviceability verification . 10
8.5.1 General . 10
8.5.2 Verification related to appearance . 10
8.5.3 Verification related to vibration . 10
8.5.4 Verification related to displacement and deformation . 10
8.6 Seismic performance verification. 10
8.7 Structural details . 10
8.7.1 Arrangement of reinforcing materials and spacing of reinforcing steel . 10
8.7.2 Covering and jacketing thickness of reinforcing materials. 11
iii
8.7.3 Joints for lateral reinforcing materials . 11
8.7.4 Anchorage of longitudinal reinforcement to footings . 11
8.7.5 Intermediate penetrating tie . 11
9 Construction .11
9.1 General . 11
9.2 Prior investigation and construction plan.12
9.3 Surface treatment . 13
9.4 Assembly of reinforcing materials . 13
9.5 Execution of concrete jacketing . 14
9.6 Execution of mortar jacketing . 14
9.6.1 Surface preparation . 14
9.6.2 Storage, mixing and transportation of jacketing materials . 14
9.6.3 Execution of mortar jacketing . 14
9.6.4 Curing . 14
9.7 Surface protection . 15
9.8 Quality control . 15
9.9 Inspection . 15
10 Records . .15
11 Maintenance .15
Annex A (informative) Examples of design and execution .16
iv
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO document should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use
of (a) patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed
patent rights in respect thereof. As of the date of publication of this document, ISO had not received
notice of (a) patent(s) which may be required to implement this document. However, implementers are
cautioned that this may not represent the latest information, which may be obtained from the patent
database available at www.iso.org/patents. ISO shall not be held responsible for identifying any or all
such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 71, Concrete, reinforced concrete and pre-
stressed concrete, Subcommittee SC 7, Maintenance and repair of concrete structures.
A list of all parts in the ISO 5091 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
v
Introduction
As a repairing and strengthening method, attaching of cementitious material layer to surface of existing
concrete structures has been widely accepted. Since the cementitious layer does not have enough tensile
strength, tension reinforcement is generally placed in the cementitious layer. There are two types of
attaching way. For the first way, the cementitious layer is attached either on top surface or bottom
surface of horizontal concrete members, especially slabs, while, for the second way, the cementitious
layer is attached to jacket vertical concrete members, especially columns. There has not been any ISO
standard on design, execution and maintenance for this method with attaching cementitious layer. The
ISO 5091 series serves as the first ISO standard for the intervention by attaching cementitious material
layer with tension reinforcement inside.
At the same time, the ISO 5091 series is the first ISO standard developed for a specific intervention
method, which conforms to the umbrella code, ISO 16311, especially ISO 16311-3 and ISO 16311-4.
The ISO 5091 series consists of four parts. ISO 5091-1 provides the issues common to all three parts,
while ISO 5091-2, 3 and 4 provide the issues specific to each attaching way of cementitious material
layers.
The jacketing is cases of intervention in which the jacketing method is used to repair or strengthen
concrete structures such as reinforced concrete bridge piers damaged by seismic actions. When
a damaged concrete structure is repaired or strengthened using the jacketing method, the status of
damage such as concrete cracking and spalling are grasped through a prior investigation and crack
injection or sealing, patching repair and other measures are taken in advance as necessary.
The ISO 5091 series can serve as a practical standard for construction industry, such as client, design
consultant and general contractor, to apply the structural intervention with externally attached
cementitious layer. Additional technical information, which is not provided explicitly in the ISO 5091
series, needs to be provided in each application case with consideration of the provisions of the ISO 5091
series.
vi
INTERNATIONAL STANDARD ISO 5091-4:2023(E)
Structural intervention of existing concrete structures
using cementitious materials —
Part 4:
Jacketing
1 Scope
This document specifies the standard requirements regarding design, construction and maintenance
to be applied for structural intervention using the jacketing method, which places reinforcing materials
such as reinforcing steel or fibre-reinforced polymer (FRP) grids around the periphery of existing
concrete column or beam and jackets these members with cementitious materials.
This document specifies structural intervention of existing concrete structures using cementitious
materials design and execution principles, and strategies for defects and on-going deterioration
including, but not limited to:
a) mechanical actions, e.g. fatigue, impact, overloading, movement caused by settlement, blast,
vibration, and seismic actions;
b) chemical and biological actions from environments, e.g. sulfate attack, alkali-aggregate reaction;
c) physical actions, e.g. freeze–thaw, thermal cracking, moisture movement, salt crystallization, fire,
and erosion;
d) reinforcement corrosion;
e) original construction defects that remained unaddressed from the time of construction.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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.
ISO 5091-1:2023, Structural intervention of existing concrete structures using cementitious materials —
Part 1: General principles
ISO 22966, Execution of concrete structures
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
jacketing
method in which additional cementitious materials and associated reinforcement are added to the
periphery of the existing concrete member to increase its strength, stiffness and/or ductility
Note 1 to entry: It is applicable to columns, bridge piers, rigid-frame pier beams, etc.
3.2
bonding product
material, such as a primer or adhesive, that is applied to bond concrete and mortar
Note 1 to entry: The grouting material for bonding concrete and reinforcing material is also included in this term.
3.3
filling material
material injected to fill the gap between a reinforcing material, such as intermediate penetrating tie,
and concrete
3.4
intermediate penetrating tie
reinforcing member, generally made of steel or fibre-reinforced polymer (FRP), that is installed inside
the drilled hole and glued into the concrete substrate to improve the ductility and shear strength of
bridge piers
3.5
reinforcing material
steel or FRP material used to sustain, restore or improve the mechanical performance of a structure
3.6
polymer hydraulic cement mortar
hydraulic composition made cementitious materials and fine aggregate modified by the addition of a
polymer
3.7
FRP grid
resin-impregnated FRP reinforcing materials formed into a grid shape
4 Investigation of existing structure
4.1 General
The investigation of the existing structure for which to consider intervention using the jacketing
method shall be conducted as set forth in ISO 5091-1:2023, Clause 4.
When an earthquake-affected structure is repaired or strengthened using the jacketing method, the
status of damage to that structure shall be studied in detail.
4.2 Investigation
4.2.1 Investigation using documents, records
An investigation using documents, records, etc. shall be conducted in accordance with ISO 5091-1:2023,
4.2.1.
Details of the materials used in the target existing structure and the structural specifications shall be
understood from the design documents created at the time of construction, the design documents for
the intervention work performed before the consideration of intervention.
4.2.2 On-site investigation
The on-site investigation on the existing structure shall be conducted in accordance with
ISO 5091-1:2023, 4.2.2. Specifically, an earthquake-affected structure shall involve studying the status
of damage caused by the earthquake in detail.
In the structural performance evaluation based on the appearance changes, the grades of structural
performance shall be established on mechanical grounds taking into full consideration the degree
of each graded appearance change and the impact of the changed region on structural performance.
Appearance changes can be classified into the following three grades.
— Grade I: No or minor damage
— Grade II: Moderate damage
— Grade III: Severe damage
The mechanical resistance of the change region should be classified into the following four levels.
— Level a: Resistance remaining intact
— Level b: Slightly degraded resistance
— Level c: Significantly degraded resistance
— Level d: No resistance
5 Intervention design
5.1 General
In the intervention design using the jacketing method, a rational structural plan shall be formulated,
and structural details shall be established based on that plan so that the structure after intervention
fulfils the required performance throughout the remaining design service life.
When an earthquake-affected structure is repaired or strengthened using the jacketing method,
it is necessary to take appropriate measures for the members damaged by the earthquake first. The
intervention plan shall be considered.
5.2 Structural plan
In the intervention plan using the jacketing method, the intervention method shall be selected,
taking into consideration the structural properties, materials, construction method and restrictions,
maintenance method, economy to ensure that the required performance is fulfilled under the
environmental conditions of the structure, factoring in the structure’s importance.
In the design phase, it can be considered that the public safety requirements regarding the spalling off
of the jacketing part and other public disaster risks for users of the structure, third parties, etc. are met
if the requirements set forth in 8.3 are met.
5.3 Structural details
In intervention using the jacketing method, structural details shall be determined so as to ensure the
integrity between the existing members and jacketing parts.
The members to be repaired or strengthened using the jacketing method, the range of intervention, the
arrangement of reinforcing materials around the periphery of the existing members, the thicknesses of
reinforcing material covering and jacketing material, etc. shall be established appropriately so that the
performance requirements of the structure are met.
If the flexural load-carrying capacity needs to be improved, the reinforcement placed around the
periphery shall be anchored securely enough to the existing parts.
If the ductility needs to be improved, it is advisable to consider placing intermediate penetrating tie
according to the cross-sectional shape of the existing structure.
6 Materials
6.1 General
The materials used for jacketing shall be of proven quality to ensure that the required performance is
fulfilled for a necessary period. Specifically, for jacketing for the seismic strengthening of an existing
structure, materials shall be selected to ensure the integrity between the existing parts and jacketing
parts so that the structure repaired or strengthened through jacketing fulfils the seismic performance.
6.2 Materials in existing structure
The characteristic values of material strength, design values and material factors of the materials in an
existing and earthquake-affected structure shall be determined in accordance with ISO 5091-1:2023,
6.2.
When intervention is targeted at an earthquake-affected structure, the materials in the existing
structure can have incurred severe damage, such as yielding or buckling of reinforcing steel, cracking of
concrete or crushing of core concrete, and the impact of that damage shall be evaluated appropriately.
If any measure such as cracking repair or patching repair has been taken for such damage prior to
intervention through jacketing, the characteristic values, design values and material factors of the
materials in the existing part shall be determined, appropriately taking into consideration the influence
of that measure as necessary.
6.3 Materials used in repairing or strengthening parts
6.3.1 General
The quality of the materials used in the parts repaired or strengthened through jacketing shall be as set
forth in ISO 5091-1:2023, 6.3.
Table 1 shows the classification of the materials used for jacketing. In this document, they refer to the
following materials.
— Primer used to improve the bond strength of the existing concrete and mortar.
— Anchor grouting material used to anchor longitudinal reinforcement or other reinforcing materials
to footings.
— Adhesive used to bond reinforcing materials and existing concrete. It is mainly used for a construction
method that requires a bond for reinforcing materials placed in grooves on existing concrete cover
or for bonding intermediate penetrating tie.
Table 1 — Types of materials used for jacketing
Construction Cementitious mate- Reinforcing materials Bonding products Filling mate-
method rials rials
— Reinforcing steel
— Prestressing steel
— Primer
Concrete jacketing — Concrete
— Non-shrink
— FRP reinforcing
— Anchor grouting
grout
materials
material
— Mortar
— Reinforcing steel
— Adhesive
Mortar jacketing — Mortar
— FRP reinforcing
materials
6.3.2 Cementitious materials
The cementitious materials used for jacketing shall be selected in accordance with ISO 5091-1:2023,
6.3.2.
In principle, as the concrete used for concrete jacketing, high-quality materials having the required
level of workability appropriate for construction through jacketing shall be selected and an appropriate
mix proportion shall be established by performing trial mixing so as to minimize the change in quality
over time after hardening.
When appropriate testing and analysis have confirmed that the compressive strength and other
material properties of the concrete, which have been created with an appropriate mixing design
through the use of materials of proven quality, will exhibit almost no change over time, the material
properties at the time of verification may be used as those for intervention construction.
With the jacketing method, reinforcing materials, such as reinforcing steel, are placed on the outer
surface of the existing structure. It is therefore advisable to make the reinforcement covering of the
jacketing concrete sufficiently thick or, if necessary, provide the jacketing parts with surface protection
so as to ensure that the reinforcing materials deteriorate as little as possible over time. When
deterioration in the material properties over time can be prevented through appropriate protection,
the material properties at the time of verification may be used as those for intervention construction.
As the mortar used for mortar jacketing, materials with proven quality and safety for which an
appropriate mix proportion is established shall be used according to the type of spraying or trowelling
work.
As the materials for dry or wet spraying, those proven to meet the quality and safety requirements for
spraying mortar shall be used. Table 2 shows typical examples of the composition of the materials used
in spraying mortar.
Table 2 — Typical examples of the composition of the materials used in spraying mortar
Materials Materials for dry spraying Materials for wet spraying
Cement Ultrarapid hardening cement Portland cement, Portland blast-fur-
(high early strength Portland nace slag cement, Portland fly ash
cement or normal Portland cement and calcium-aluminate
cement to be used depending cement
on circumstances)
a
Fine aggregate Dry natural fine aggregate Dry natural fine aggregate and
lightweight
Aggregate
Fibre Steel fibre and organic fibre Mainly organic fibre
b
Cement mixing polymer Polymer dispersion Polymer dispersion and redispersi-
ble polymer powder
Water reducing agent - Can be used.
Water retention agent - Used in many cases.
Accelerant - Can be used when thickening is
required for construction in cold
Admixture
weather.
Retarder - Can be used for construction in hot
weather.
c
Quick setting agent Can be used. Can be used.
Expansive additive - Used in many cases.
Fine powder Can be used. Used in many cases.
Water Tap water is used normally.
a
Mainly mechanically stabilized prepacked aggregate.
b
In the case of polymer hydraulic cement mortar.
c
When high early strength Portland cement or ordinary Portland cement is used.
6.3.3 Reinforcing materials
The reinforcing materials used for jacketing shall be selected in accordance with ISO 5091-1:2023, 6.3.3.
The reinforcing steel and FRP materials shall be checked to confirm that they possess mechanically
reliable material properties including strength, elongation capacity, Young's modulus and coefficient of
linear thermal expansion. Steel materials that fulfil the quality requirements set forth in the relevant
national standards should be used.
The durability of an FRP reinforcing material varies depending on the types of continuous fibre and
matrix resin. It is necessary to check the durability of the composite material after molding.
6.3.4 Bonding products
The bonding products used for jacketing shall be selected in accordance with ISO 5091-1:2023, 4.3.5.
A primer that meets the performance requirements shall be selected so that stress is transferred
between the existing concrete and the cementitious materials of the jacketing parts.
With the mortar jacketing method, a primer is generally applied before the jacketing of mortar to
ensure the transfer of stress between the existing concrete and mortar. A primer of proven quality that
ensures the bonding property of the existing concrete and mortar shall be selected according to the
type of mortar used.
An anchor grouting material that has the required strength and ensures the anchorage strength
between the existing concrete and reinforcement shall be selected.
An adhesive having the required strength and capable of integrating the existing concrete and
reinforcing materials shall be selected.
The adhesive shall also meet the quality requirements related to construction, such as the viscosity and
fluidity appropriate for the construction work at the site.
6.3.5 Filling materials
A filling material having the required fluidity that reliably fills the gap between the reinforcing
materials and existing concrete shall be selected.
A filling material having appropriate workability and corrosion inhibitor shall be selected considering
the space between the reinforcing materials and concrete and the injection method.
6.4 Characteristic values and design values of materials
6.4.1 General
The characteristic values and design values of the materials used for jacketing shall be as set forth in
ISO 5091-1:2023, 6.4.
6.4.2 Cementitious materials
The characteristic values and design values of the cementitious materials used for jacketing shall be as
set forth in ISO 5091-1:2023, 6.4.2.
6.4.3 Reinforcing materials
The characteristic values and design values of the reinforcing materials used for jacketing shall be as
set forth in ISO 5091-1:2023, 6.4.3.
6.4.4 Bonding products
The characteristic values and design values of the bonding products used for jacketing shall be as set
forth in ISO 5091-1:2023, 6.4.4.
7 Actions
7.1 General
The actions to be considered in the performance verification of a structure repaired or strengthened
using the jacketing method shall be as set forth in ISO 5091-1:2023, Clause 7.
7.2 Actions for intervention design
The actions to be considered for the intervention design shall be as set forth in ISO 5091-1:2023, 7.2.
8 Performance verification for repaired or strengthened structure
8.1 General
The items to be verified for the members repaired or strengthened through jacketing shall be established
appropriately to ensure that the structure meets its performance requirements after intervention.
For members configured so that the existing concrete and jacketing parts behave as one, the verification
can be performed in accordance with Clause 8. If no integrity is ensured between the existing concrete
and jacketing parts, the performance verification shall be performed by means of an appropriate
method, such as analyses and experiments, in accordance with ISO 5091-1.
If the existing concrete and jacketing parts cannot be thought to be integrated or, in other words, if it
is necessary to take into consideration any separation or slip at the interface between the jacketing
parts and existing concrete, the performance verification needs to be performed through appropriate
analyses and experiments, factoring in the effect of the separation or slip.
8.2 Calculation of response values
8.2.1 General
The response values of a structure repaired or strengthened through jacketing shall be calculated as
set forth in ISO 5091-1:2023, 8.2.
8.2.2 Modelling of structure
A structure repaired or strengthened through jacketing shall be modelled in accordance with
ISO 5091-1:2023, 6.2.2 according to the required performance of the structure.
Members repaired or strengthened through jacketing shall be modelled appropriately, taking into
consideration the cross-sectional shape after intervention, and the range of strengthening and
anchorage length shall be taken into account.
The materials of members repaired or strengthened through jacketing shall be modelled in accordance
with ISO 5091-1.
A structure repaired or strengthened through jacketing shall be modelled appropriately based on
inspection and diagnosis results, taking into consideration the degradation of and damage to the
existing members.
8.2.3 Structural analysis
The structural analysis of a structure repaired or strengthened through jacketing shall be performed
as set forth in ISO 5091-1:2023, 8.2.3.
8.2.4 Calculation of response
The response of members repaired or strengthened through jacketing shall be calculated as set forth in
ISO 5091-1:2023, 8.2.4.
8.3 Durability verification
The durability of a structure repaired or strengthened through jacketing shall be verified as set forth
in ISO 5091-1:2023, 8.3 in order to check that the structure is not subject to changes over time, such
as steel corrosion due to environmental actions and degradation of the existing concrete and the
cementitious materials of the jacketing parts, or that the degree of such change remains minor.
8.4 Safety verification
8.4.1 General
In general, the safety of a structure repaired or strengthened through jacketing shall be verified by
establishing a limit state for cross-sectional failure.
8.4.2 Verification related to failure
8.4.2.1 General
The verification related to failure shall be generally performed with respect to bending moment, axial
force, shear capacity and torsion.
8.4.2.2 Verification related to bending moment and axial force
The safety verification related to bending moment and axial force shall be performed taking into
consideration the state of failure appropriately.
The strength can be calculated assuming that the existing and jacketing parts are integrated as one and
that multiple layers of reinforcing materials are placed.
When strength is calculated in a verification such as the verification related to the limit state of failure
of a member subject to bending moment, as well as to bending moment and axial force, the model can be
used for the stress-strain curve of concrete.
When the physical properties of the concrete of the jacketing parts can be deemed to be identical to
those of the existing concrete, the stress-strain curve of the existing concrete may be assumed.
The stress-strain curve of the cementitious materials used for the jacketing parts shall be as set forth in
ISO 5091-1:2023, 6.4.2.
When strength is calculated in a verification such as the verification related to the limit state of failure,
the impact on the cross-section shall be taken into consideration and, if the cementitious materials can
be deemed to be the same as the existing concrete, the stress-strain curve of the existing concrete can
be assumed.
When strength is calculated in a verification such as the verification related to the limit state of failure,
the model can be used for the stress-strain relationship of steel.
The stress-strain curve of FRP reinforcing materials shall be as set forth in ISO 5091-1:2023, 6.4.3.
8.4.2.3 Verification related to shear force
In principle, the safety verification related to shear force shall be performed with respect to the design
shear capacity V and design diagonal compressive failure strength of the web concrete V ,
yd wcd
respectively, taking into consideration the state of failure appropriately. The calculation example is
shown in Annex A. The safety of members that are modelled as simple beams or cantilever beams shall
be verified with respect to both design shear capacity and design diagonal compressive failure strength.
If the shear span to depth ratio is small, however, the safety shall be verified with respect to design
diagonal compressive failure strength.
As for the shear reinforcement of the jacketing parts, only that wrapped around the entire periphery of
the existing members is taken into consideration in principle.
When not wrapped around the entire periphery, the shear reinforcement of the jacketing parts is not
anchored completely and may fail to function effectively. Therefore, only the shear reinforcement
wrapped around the entire periphery of the existing members shall be taken into consideration in
principle.
8.4.2.4 Verification related to torsional moment
If the action of the torsional moment is not negligible, a safety study shall be performed by means of an
appropriate method.
If the action of torsional moment is substantial and its impact on the safety of the structure cannot be
ignored, a safety verification shall be performed with respect to torsion. The impact on the cementitious
materials and reinforcing materials of the jacketing parts should be checked through appropriate
analyses, experiments or other means.
8.5 Serviceability verification
8.5.1 General
The serviceability verification for a structure repaired or strengthened through jacketing shall involve
a verification related to appearance, a verification related to vibration and verification related to
displacement and deformation if necessary.
8.5.2 Verification related to appearance
The appearance of a structure repaired or strengthened through jacketing shall be verified as set forth
in ISO 5091-1:2023, 8.5.3.
8.5.3 Verification related to vibration
The verification related to vibration for a structure repaired or strengthened through jacketing shall
be performed as set forth in ISO 5091-1:2023, 8.5.4 and involve checking by means of an appropriate
method that the vibration of the repaired or strengthened structure does not affect the comfort in use
of the structure itself or any surrounding structure.
8.5.4 Verification related to displacement and deformation
The verification related to displacement and deformation shall involve checking by means of an
appropriate method that the comfort in use is not affected by the displacement or deformation that
occurs in a structure repaired or strengthened through jacketing.
8.6 Seismic performance verification
When a seismic performance verification is performed for members repaired or strengthened through
jacketing, a level of seismic performance and a limit value of damage corresponding to that seismic
performance level shall be established in advance.
Establishing the seismic performance of a structure shall involve taking into consideration the
response properties of the structure corresponding to the assumed earthquake scale. In addition to
the behaviour duri
...