(800) (562) A Subsidiary of the International Code Council

Transcription

1 (800) (56) A Subsidiary o the International Code Counil ACCEPTANCE CRITERIA FOR CONCRETE AND REINFORCED AND UNREINFORCED MASONRY STRENGTHENING USING EXTERNALLY BONDED FIBER-REINFORCED POLYMER (FRP) COMPOSITE SYSTEMS AC15 Approved February 010 Eetive Marh 1, 010 Previously approved Otober 009, June 003, April 1997; editorially orreted June 007 PREFACE Evaluation reports issued by ICC Evaluation Servie, In. (ICC-ES), are based upon perormane eatures o the International amily o odes and other widely adopted ode amilies, inluding the Uniorm Codes, the BOCA National Codes, and the SBCCI Standard Codes. Setion o the International Building Code reads as ollows: The provisions o this ode are not intended to prevent the installation o any materials or to prohibit any design or method o onstrution not speiially presribed by this ode, provided that any suh alternative has been approved. An alternative material, design or method o onstrution shall be approved where the building oiial inds that the proposed design is satisatory and omplies with the intent o the provisions o this ode, and that the material, method or work oered is, or the purpose intended, at least the equivalent o that presribed in this ode in quality, strength, eetiveness, ire resistane, durability and saety. Similar provisions are ontained in the Uniorm Codes, the National Codes, and the Standard Codes. This aeptane riteria has been issued to provide all interested parties with guidelines or demonstrating ompliane with perormane eatures o the appliable ode(s) reerened in the aeptane riteria. The riteria was developed and adopted ollowing publi hearings onduted by the ICC-ES Evaluation Committee, and is eetive on the date shown above. All reports issued or reissued on or ater the eetive date must omply with this riteria, while reports issued prior to this date may be in ompliane with this riteria or with the previous edition. I the riteria is an updated version rom the previous edition, a solid vertial line ( ) in the margin within the riteria indiates a tehnial hange, addition, or deletion rom the previous edition. A deletion indiator ( ) is provided in the margin where a paragraph has been deleted i the deletion involved a tehnial hange. This riteria may be urther revised as the need ditates. ICC-ES may onsider alternate riteria, provided the report appliant submits valid data demonstrating that the alternate riteria are at least equivalent to the riteria set orth in this doument, and otherwise demonstrate ompliane with the perormane eatures o the odes. Notwithstanding that a produt, material, or type or method o onstrution meets the requirements o the riteria set orth in this doument, or that it an be demonstrated that valid alternate riteria are equivalent to the riteria in this doument and otherwise demonstrate ompliane with the perormane eatures o the odes, ICC-ES retains the right to reuse to issue or renew an evaluation report, i the produt, material, or type or method o onstrution is suh that either unusual are with its installation or use must be exerised or satisatory perormane, or i maluntioning is apt to ause unreasonable property damage or personal injury or sikness relative to the beneits to be ahieved by the use o the produt, material, or type or method o onstrution. Aeptane riteria are developed or use solely by ICC-ES or purposes o issuing ICC-ES evaluation reports. Copyright 010

2 ACCEPTANCE CRITERIA FOR CONCRETE AND REINFORCED AND UNREINFORCED MASONRY STRENGTHENING USING EXTERNALLY BONDED FIBER-REINFORCED POLYMER (FRP) COMPOSITE SYSTEMS (AC15) 1.0 INTRODUCTION 1.1 Purpose: The purpose o this riteria is to establish minimum requirements or the issuane o ICC Evaluation Servie, In. (ICC-ES), evaluation reports on iber-reinored polymer (FRP) omposite systems under the 009 and 006 International Building Code (IBC) and the 1997 Uniorm Building Code (UBC). Bases o reognition are IBC Setion and UBC Setion The reason or the development o this riteria is to provide guidelines or the evaluation o alternative onrete and masonry strutural systems, where the odes do not provide requirements or testing and determination o strutural apaities, reliability and servieability o these produts. 1. Sope: This aeptane riteria applies to passive FRP omposite systems used to strengthen existing onrete and masonry strutural elements. Properties evaluated inlude lexural, and shear apaities, perormane under environmental exposures, perormane under exposure to ire onditions, and strutural design proedures. 1.3 Reerened Codes and Standards: International Building Code (009 IBC), International Code Counil International Building Code (006 IBC), International Code Counil Uniorm Building Code (UBC), International Conerene o Building Oiials ICC-ES Aeptane Criteria or Inspetion and Veriiation o Conrete and Reinored and Unreinored Masonry Strengthening Using Fiber-reinored Polymer (FRP) Composite Systems (AC178) ASTM C 97-94, Test Method or Tensile Strength o Flat Sandwih Construtions in Flatwise Plane, ASTM International ASTM C , Pratie or Determining the Chemial Resistane o Thermosetting Resins Used in Glass-Fiber-Reinored Strutures Intended or Liquid Servie, ASTM International ASTM D , Standard Test Method or Coeiient o Linear Thermal Expansion o Plastis Between -30EC and 30EC with a Vitreous Silia Dilatometer, ASTM International ASTM D , Pratie or Preparation o Substitute Oean Water, ASTM International ASTM D 47-97, Pratie or Testing Water Resistane o Coatings in 100% Relative Humidity, ASTM International ASTM D (1995), Test Method or Apparent Interlaminar Shear Strength o Parallel Fiber Composites by Short-Beam Method, ASTM International ASTM D , Test Method or Ignition Loss o Cured Reinored Resins, ASTM International ASTM D , Test Methods or Tensile, Compressive, and Flexural Creep and Creep Rupture o Plastis, ASTM International ASTM D , Standard Test Methods or Impat Resistane o Flat, Rigid Plasti Speimens by Means o a Tup (Falling Weight), ASTM International ASTM D , Standard Test Method or Tensile Properties o Polymer Matrix Composite Materials, ASTM International ASTM D , Standard Pratie or Heat Aging o Plastis Without Load, ASTM International ASTM D , Speiiation or Flexible Poly (Vinyl Chloride) Plasti Sheeting or Pond, Canal, and Reservoir Lining, ASTM International ASTM D , Standard Test Method or Strength Properties o Adhesives in Shear by Tension Loading o Single-Lap-Joint Laminated Assemblies, ASTM International ASTM D , Standard Test Method or Constituent Content o Composite Materials, ASTM International ASTM D , Standard Pratie or Determining and Reporting Dynami Mehanial Properties o Plastis, ASTM International ASTM D , Standard Test Method or Pull-o Strength o Coatings Using Portable Adhesion Testers, ASTM International ASTM E (1996), Standard Pratie or Maintaining Constant Relative Humidity by Means o Aqueous Solutions, ASTM International ASTM E , Standard Test Method or Linear Thermal Expansion o Solid Materials by Thermomehanial Analysis, ASTM International ASTM E , Standard Terminology Relating to Thermophysial Properties, ASTM International ASTM G Standard Pratie or Operating Enlosed Carbon Ar Light Apparatus or Exposure o Nonmetalli Materials, ASTM International..0 DEFINITIONS.1 Design Values: The FRP omposite material s load and deormation design apaities, that are based on either working stress or ultimate strength methods.. Composite Material: A ombination o highstrength ibers and polymer matrix material. This FRP omposite may be applied either during manuature o the strutural element or at the projet loation..3 Craking Load and Displaement: Load and displaement at whih the moment-urvature relationship o the onrete or masonry setion irst hanges slope or at whih the raking moment is reahed..4 Yielding Load and Displaement: Load and displaement at whih longitudinal steel reinorement o the onrete or masonry setion irst yields.

3 .5 Passive and Ative Composite Systems: Ative systems are those FRP omposite systems where the FRP omposite materials are post-tensioned ater installation by means suh as pressure injetion between the omposite material and the onrete or masonry setion. Passive systems are not post-tensioned ater installation. Ative systems are outside the sope o this riteria. 3.0 REQUIRED INFORMATION 3.1 Desription: A detailed desription o the strengthening system is needed, inluding the ollowing items: 1. Desription and identiiation o the produt or system. Identiiation shall inlude the ICC-ES evaluation report number.. Restritions or limitations on use. 3. Installation Instrutions: Instrutions shall inlude the ollowing items. 1. Desription o how the produt or system will be used or installed in the ield.. Proedures establishing quality ontrol in ield installation. 3. Requirements or produt handling and storage. 4. Fastener installation into strutural elements. 5. For systems that depend on bond between the system and the substrate, on-site testing o bond to the substrate is required. 3.3 Strutural Design: The strutural appliations o the system shall address the ollowing items: 1. Clariiation o reognition under either Chapter 19 or Chapter 1 o the IBC or UBC.. Complete desription o details. 3. Details on how the produt or system does or does not omply with Chapter 19 o the IBC or UBC, inluding onormities and deviations. Details shall inlude positive statements that the produt or system does omply with Chapter 19 or 1 o the IBC or UBC in the ollowing areas... ; and negative statements that it does not omply in the ollowing areas Details and examples o how the produt or system is designed and analyzed, inluding ormulas, with proedures and properties needed or design and analysis. The engineering analysis shall deine ailure modes or ore and deletion limit states. 5. Use o anhors shall be onsidered where the FRP omposite material bond to substrate is ritial. 4.0 TESTING LABORATORIES AND REPORTS OF TESTS 4.1 Testing laboratories shall omply with Setion.0 o the ICC-ES Aeptane Criteria or Test Reports (AC85) and Setion 4. o the ICC-ES Rules o Proedure or Evaluation Reports. 4. Test reports shall omply with AC Produt Sampling: Produts shall be sampled in aordane with Setion 3.1 o AC QUALIFICATION TESTS 5.1 Qualiiation Test Plan: The intent o testing is to veriy the design equations and assumptions used in the engineering analysis. All or part o the tests desribed in this setion, and any additional tests identiied or speial eatures o the produt or system, shall be speiied. The test plan shall be a omplete doument. Overall, qualiiation testing must provide data on material properties, ore and deormation limit states, and ailure modes, to support a rational analysis proedure. The speimens shall be onstruted under onditions speiied by the manuaturer, inluding uring. Tests must simulate the antiipated loading onditions, load levels, deletions, and dutilities. 5. Columns: 5..1 Flexural Tests: Coniguration: Column speimens shall be onigured to indue lexural limit states or ailure modes. Either antilever or double ixity (reverse urvature) is permitted in speimens. Extremes o dimensional, reinoring, and strength parameters shall be onsidered Proedure: For seismi or wind-load appliations, the lateral load proedure shall onorm to Figure 3. For gravity (nondynami) loading appliations, the load may be monotonially applied. Axial loads within a speii range shall be applied. The limit states shall be determined based on material properties and an extreme onrete or masonry iber ompression strain o Shear Tests: Coniguration: Column speimen spans shall be onigured to indue shear limit states or ailure modes. Double ixity (reverse urvature) is required. Extremes o dimensional, reinoring, and ompressive strength parameters shall be onsidered Proedure: For seismi or wind-load appliation, the lateral load proedure shall onorm to Figure 3. For gravity (nondynami) loading appliation, the load may be monotonially applied. Axial loads within a speii range shall be applied. The limit states shall be determined based on material properties. 5.3 Beam-to-Column Joints: Coniguration: The beam-to-olumn joint shall be onigured to indue joint-related limit states or ailure modes. The olumn portion may be onstruted to represent a setion between inletion points. Extremes o dimensional, reinoring and ompressive strength parameters shall be onsidered Proedure: The lateral load proedure shall onorm to Figure 3. A vertial load shall be ontinuously applied and varied within a speiied range. The limit states shall be determined based on material properties. 5.4 Beams: Flexural Tests: Coniguration: Beam spans shall be onigured to indue lexural limit states or ailure modes. Either simple or rigid supports are permitted. Extremes o dimensional, reinoring, and ompressive strength parameters shall be onsidered.

4 Proedure: For seismi or wind-load appliation, the lateral load proedure shall onorm to Figure 3. For gravity (nondynami) loading appliation, the load may be monotonially applied. The limit states shall be determined based on material properties and an extreme onrete or masonry iber ompression strain o Shear Tests: Coniguration: Beam spans shall be onigured to indue shear limit states or ailure modes. Either simple or rigid supports are permitted. Extremes o dimensional, reinoring, and ompressive strength parameters shall be onsidered Proedure: For seismi or wind loading, the lateral load proedure shall onorm to Figure 3. For gravity loading, the load may be monotonially applied. The limit states shall be determined based on material properties. 5.5 Walls: Wall Flexural Tests (Out-o-Plane Load): Coniguration: Wall lexural speimens shall be onigured to indue out-o-plane lexural limit states and ailure modes. Extremes o dimensional, reinoring, and ompressive strength parameters shall be onsidered Proedure: Speimens may be axially loaded to onsider eets o axial loads. The loading in the out-o-plane diretion may be applied at third-points, by air-bags or by other means representing atual onditions. The lateral load proedure onsists o: Load speimens in both diretions, to ind raking and yielding load and deormation at irst raking. For unreinored masonry, only raking load and deormation are required At least two yles o loading in both diretions under displaement ontrol at eah deormation level. The deormation levels shall onsist o multiples o the deormation at yielding or reinored onrete or masonry setions or raking or unreinored masonry setions The speimens are loaded in both diretions until the strengthening system is damaged, its apaity is reahed, or desired limit states are ahieved Wall Shear Tests (In-Plane Shear): Coniguration: Wall speimens shall be onigured to indue in-plane shear limit states or ailure modes. Extremes o dimensional, reinoring and ompressive strength parameters shall be onsidered Proedure: Speimens may by axially loaded to onsider eets o axial loads. The lateral load proedure onsists o: Load speimens in both diretions to ind raking and yielding load and deormation. For unreinored masonry, only raking load and deormation are required The speimens are loaded in both diretions until the strengthening system is damaged, its apaity is reahed, or desired limit states are ahieved. 5.6 Wall-to-Floor Joints: Conigurations: The speimens shall be onigured to indue joint-related limit states or ailure modes. Extremes o dimensional, reinoring and ompressive strength parameters shall be onsidered Proedure: For seismi or wind-loading appliations, the lateral load proedure shall onorm to Figure 3. For gravity load appliations, the load may be monotonially applied. The vertial load shall be applied to loors. The limit states shall be determined based on material properties. 5.7 Slabs (Flexural Tests): Coniguration: Slab spans shall be onigured to inlude lexural limit states or ailure modes. Either simple or rigid supports are permitted. Extremes o dimensional, reinoring and ompressive strength shall be onsidered Proedure: For seismi or wind-load appliations, the lateral load proedure shall onorm to Figure 3. For gravity (nondynami) loading appliation, the load may be monotonially applied. The limit states shall be determined based on material properties and an extreme onrete iber ompression strain o Physial and Mehanial Properties o FRP Composite Materials: Required physial and mehanial properties are shown in Table. These properties, inluding reep, CTE and impat, shall be onsidered in the design riteria and limitations. 5.9 Exterior Exposure: Proedure: Strutural FRP omposite materials are tested aording to ASTM G 153. Six speimens, measuring 3 / 4 inh by 10 inhes (19.1 by 54 mm), are required. These speimens also may be ut rom a panel that has been oated and painted to represent end-use onditions. Five speimens are exposed to yles onsisting o 10 minutes light and 18 minutes light and water spray in the weatherometer hamber. Minimum duration is,000 hours. The blak-body temperature is 145 F (63 C). Both exposed and ontrol speimens are then tested to ASTM D 3039, or tensile strength, tensile modulus and elongation. Five other speimens are ontrolled samples Conditions o Aeptane: Control and exposed speimens are visually examined using 5 magniiation. Surae hanges aeting perormane, suh as erosion, raking, razing, heking, and halks, are subjet to urther investigation. The speimens shall retain at least 90 perent o tensile properties generated on ontrol speimens Freezing and Thawing: Proedure: Fiteen samples are onditioned in a 100 perent relative humidity hamber at 100 F (38 C) or three weeks. Eah yle is 4 hours, minimum, in a 0 F (-18 C) reezer ollowed by 1 hours, minimum, in the humidity hamber. At least twenty yles are required. Control speimens and yled speimens are then tested aording to Table or tensile strength, tensile modulus, elongation, glass transition temperature, and interlaminar shear strength. Speimens are tested in the primary diretion. 4

5 5.10. Conditions o Aeptane: Control speimens and yled speimens are visually examined using 5 magniiation. Surae hanges aeting perormane, suh as erosion, raking, razing, heking and halking, are unaeptable. The yled speimens shall retain at least 90 perent o the tensile properties determined or onditioned speimens Aging: These tests shall be onsidered in design riteria and limitations Proedure: Both wet and dry speimens are aged aording to Table 3. Both exposed and ontrol speimens are then tested to Table or tensile strength, tensile modulus, elongation, glass transition temperature, and interlaminar shear strength. Speimens are tested in the primary diretion. Five speimens per ondition are required Conditions o Aeptane: Control and exposed speimens are visually examined using 5 magniiation. Surae hanges aeting perormane, suh as erosion, raking, razing, heking, and halking, are unaeptable. The exposed speimens shall retain the perentage o tensile properties generated on onditioned speimens noted in Table Alkali Soil Resistane: Proedure: Tests are done on ive speimens aording to ASTM D 3083, Setion 9.5, or 1,000 hours. Both onditioned and exposed speimens are then tested or tensile strength, tensile modulus, and elongation aording to ASTM D Conditions o Aeptane: Conditioned and exposed speimens are visually examined using 5 magniiation. Surae hanges, suh as erosion, raking, razing, heking, and halking, are unaeptable. The exposed speimens shall retain at least 90 perent o tensile properties generated on onditioned speimens Fire-resistant Constrution: The eet o the FRP omposite system on ire-resistane onstrution shall be evaluated aording to Setion 703 o the IBC or UBC Interior Finish: The lassiiation o the iberreinored polymer (FRP), omposite system as an interior inish shall be determined aording to Setion 803 o the IBC or Setion 80 o the UBC Fuel Resistane: Tested speimens are tested aording to ASTM C 581. The speimens are exposed to diesel uel reagent or 4 hours, minimum. Speimens are tested aording to Table or tensile strength, tensile modulus, elongation, glass transition temperature, and interlaminar shear strength Adhesive Lap Strength: This test applies to preabriated systems. Speimens o the adhesive are tested aording to ASTM D 3165 or exposures in Table 3, and Setions 5.10 and Bond Strength: Proedure: The test applies to systems that bond to the substrate. Tests are onduted or tension aording to ASTM D 4541 or ASTM C 97 where the omposite material bonds two substrate elements together, and or shear using a method aeptable to ICC- ES sta. Speimens are exposed aording to Table 3 and Setion Conditions o Aeptane: The bond strength o FRP omposite material to onrete shall not be less than 00 psi (1378 kpa). The bond strength o the FRP omposite material to masonry shall not be less than.5 x ( m ) 0.5. In both ases, bond testing shall exhibit ailure in the onrete or masonry substrate Drinking Water Exposure: The eet o the FRP omposite system when diretly exposed to drinking water shall be evaluated based in tests in aordane with NSF QUALITY CONTROL 6.1 Manuaturing: Quality assurane proedures during manuature o the system omponents shall be desribed in a quality ontrol manual omplying with the ICC-ES Aeptane Criteria or Quality Doumentation (AC10). The quality ontrol program shall inlude periodi inspetions by an inspetion ageny urrently aredited by the International Areditation Servie, In. (IAS). 6. Installation: All installations shall be done by appliators approved by the proponent o the system. The quality assurane program shall be doumented and omply with AC178. Speial inspetion is required and shall omply with Setion 1704 o the IBC or Setion 1701 o the UBC and other setions o the appliable ode. Duties o the speial inspetor shall be desribed and inluded in the evaluation report. 7.0 FINAL SUBMITTAL 7.1 The inal submittal will onsist o a test report or test reports, and a design riteria report, as desribed in this setion. The inal submittal shall inlude the data desribed in Setion 3 o this riteria. Contents o the inal submittal are desribed in the ollowing subsetions: 7. Test Report: The independent laboratory shall report on the qualiiation testing perormed aording to the approved test plan. Besides the inormation requested in Setion 4, the test report must inlude the ollowing: 1. Inormation noted in the reerene standard.. Desription o test setup. 3. Rate and method o loading. 4. Deormation and strain measurements. 5. Modes o ailure. 6. Strain measurements. 7.3 Design Criteria: Design Criteria Report: The report shall inlude a omplete analysis and interpretation o the qualiiation test results. Design stress and strain riteria or onrete and reinored and unreinored masonry systems shall be speiied based on the analyses, but shall not be higher than speiied in Setion Design stresses and strains shall be based on a harateristi value approah veriied by test data. The CTE values determined in Table shall be onsidered in the design proedure. The reep rupture stress limits as shown in Table 1 shall be onsidered in the design proedure. 5

6 The design riteria report shall provide guidane on proteting the omposite materials in areas where they are prone to impat. The design shall onsider seondary stresses resulting when dead loads are relieved during appliation and subsequently reapplied. Adoption o the minimum aeptable standards or design outlined in Setion 7.3. does not eliminate the need or strutural testing. Situations not overed in Setion 7.3. shall be subjet to speial onsiderations and testing, and design values shall be ompatible with the onservative approah adopted in Setion 7.3., and disussed in reerene [4] Minimum Aeptable Design Criteria: Flexural Strength Enhanement o Reinored Conrete Members: Fiber-reinored polymer (FRP) omposite material bonded to suraes o onrete may be used to enhane the design lexural strength o setions by ating as additional tension reinorement. In suh ases, setion analysis shall be based on normal assumptions o a) plane setions remain plane ater loading; b) the bond between the FRP and the substrate remains peret; ) the maximum usable ompressive strain in the onrete is 0.003; d) FRP has a linear elasti behavior to ailure. The lexural strength o a reinored onrete setion depends on the ontrolling ailure mode. Failure modes or an FRP-strengthened setion inlude: Crushing o the onrete in ompression beore yielding o the reinoring steel. Yielding o the steel in tension ollowed by rupture o the FRP laminate. Yielding o the steel in tension ollowed by onrete rushing. Shear/tension delamination o the onrete over (over delamination). Debonding o the FRP rom the onrete substrate (FRP debonding). The eetive strain in FRP reinorement shall be limited to the strain level at whih debonding may our, ε d, as deined in Eq. (1a): = (1a) ε d ε u ne t ' ε d = ε u ne t (SI Units) The nominal eetive stress level in the FRP reinorement shall be alulated in aordane with Equation (1b): e =0.85.E.ε e where ε e ε d (1b) Cheks must be done to ensure that the strain in the member is at least as high as what is assumed in design. Fibers shall not have a misalignment o more than 5 degrees. Dependable lexural strengths shall be determined by multiplying the nominal lexural strength, inluding the eets o iber aording to Equation (1b), by the 6 appropriate lexural strength redution ator aording to the IBC or UBC. Design moment apaity or lexure shall be alulated in aordane with Equation (1). øm n = ø(m s +M ) (1) Servieability: The stress in the steel reinorement under servie load shall be limited to 80 perent o the yield strength s, s () y Creep Rupture and Fatigue Stress Limits: The servie stress levels in the FRP reinorement under servie load shall be limited to the values shown in Table Flexural Strength Enhanement o Masonry Elements: The lexural strength o a masonry element strengthened with FRP shall be based on the assumptions presented in Setion However, the eetive strain in FRP reinorement shall be limited to the strain level at whih debonding may our as deined in Equations (3a) and (3b): ε = (3a) e ε u = ε (3b) e E e The ore per unit width provided by FRP shall be determined rom Equation (4). = 1500 / (4) = 63 / (SI units) Axial Load Capaity Enhanement: FRP omposite material may be bonded to external suraes o onrete or masonry members to enhane axial load apaity. Retangular setions where the ratio o longer to shorter setion side dimension is not greater than.0, may have axial ompression apaity enhaned by the onining eet o FRP omposite material plaed with ibers running essentially perpendiular to the members axis. The stress-strain or FRP-onined onrete is illustrated in Figure 1 and shall be determined using the ollowing expressions: ( E E ) ( ) Eε ε 0 ε ε t = 4 + E ε ε ε ε ε t u t = E E E (5a) (5b) = (5) ε u The maximum onined onrete ompressive strength,, and the maximum oninement pressure, l, shall be alulated using Equations (6) and (7),

7 respetively with the inlusion o an additional redution ator, ψ = (6) = + ψ 3. 3κ nt E ε e D l = nt E ε e b + h a l Cirular Cross-setion Non-irular Cross-setion In Equation (7), the eetive strain level in the FRP at ailure, ε e, shall be given by: ε e = 0.55ε u (8) The minimum oninement ratio l / shall not be less than The maximum ompressive strain in the FRPonined onrete, ε u, shall not exeed 0.01 to prevent exessive raking and the resulting loss o onrete integrity. The orresponding maximum value o shall be alulated using the ollowing stress-strain relationship: 0.45 ε l e εu = ε κb 0.01 (9) ε In Equation (9), the eiieny ator, κ b, shall be alulated using Equation (10b) Cirular Setions: For irular ross setions the shape ators κ a and κ b in Equations (6) and (9), respetively, shall be taken as Retangular Setions: For retangular setions onined with transverse FRP omposite material, setion orners must be rounded to a radius not less than 3 / 4 inh (0 mm) beore plaing FRP omposite material. Axial ompression apaity enhanement by FRP omposite material to retangular setions within aspet ratio h/b >.0 shall be subjet to speial analysis onirmed by test results. The shape ators κ a in Equation (6) and κ b in Equation (9) shall be alulated using Equation (10), and is shown in Figure. κ κ where, Ae b a = A h 0.5 Ae h b = A b (( bh)( h r) ( hb)( b r) ) ( Ag ) g (7) (10a) (10b) A ρg e = (10) A 1 ρ Dutility Enhanement: FRP omposite material oriented essentially transversely to the members axis may be used to enhane lexural dutility apaity o irular and retangular setions where the ratio o longer to shorter setion dimension does not exeed.0. The 7 enhanement is provided by inreasing the eetive ultimate ompression strain o the setion Cirular Setions: Ultimate ompression strain o irular setions o diameter D, onined with iber o eetive thikness t at angle θ = 90 to the longitudinal axis o the member, shall be given by.5ρsj uj ε uj ε u = (11) where N is given by Equation (6), and ρ sj is (4t /D) Retangular Setions: Ultimate ompression strains o retangular setions o side lengths B and H where H # 1.5B, and with iber o eetive thikness t at an angle θ to the longitudinal axis o the member, shall be given by 1.5ρsj uj ε uj ε u = (1) where N is given by Equation (6) and ρ sj is t [(B+H)/BH]. For retangular setions onined with transverse FRP omposite material, setion orners must be rounded to a radius o not less than 3 / 4 inh (0 mm) beore plaing FRP omposite material. Dutility enhanement aording to Equation (1) shall not be relied on or slender members where the aspet ratio M/VB $ Lap-Splie Coninement: Lap-splies in irular olumns an be onined by jakets to prevent bond ailure. The required volumetri ratio o FRP omposite material, at an angle θ to the longitudinal axis o the member (ρ sj ) shall not be less than 1.4A ρ b s sj (13) pl s j where p is the perimeter o the rak surae orming beore splie ailure given by the lesser o Equations (14) and (15): = + ( + ) (14) = ( + d ) (15) In Equation (13), the irular setion is reinored with n bars eah o diameter d b, area A b, uniormly distributed around the setion on ore diameter DN. Required stress to be transerred is s, and the splie length l s must not be less than l s 0.05d b y (16) For SI: s = 0.3d b y u

8 The jaket stress j in Equation (13) shall not be taken larger than j = E j # 0.75 uj. Note: Retangular setions annot generally be eetively onined by retangular jakets against splie ailure, and so no provisions are inluded here Shear Strength Enhanement o Conrete Elements: Shear strength o irular and retangular setions o onrete elements an be enhaned by FRP omposite materials with iber oriented essentially perpendiular to the members axis. Shear strengthening using external FRP may be provided at loations o expeted plasti hinges or stress reversal and or enhaning post-yield lexural behavior o members in moment rames resisting seismi loads only by ompletely wrapping the setion. For external FRP reinorement in the orm o disrete strips, the enter-toenter spaing between the strips shall not exeed the sum o d/4 plus the width o the strip. The design shear strength o an FRP-strengthened onrete member an be determined using Eq. (17). An additional redution ator shall be applied to the ontribution o the FRP system, as ollows: 0.85 or three-sided FRP U-wrap or two-sided strengthening shemes; 0.95 or ully wrapped setions. ( V + V ψ V ) φ V + n = φ s (17) The shear ontribution o the FRP shear reinorement shall given by Equation (18) V where: A = v A v = nt w e = ε e E e ( sinα + osα) d s v (18) The eetive design strain ε e is the maximum strain that shall be ahieved in the FRP system at the nominal strength and is governed by the ailure mode o the FRP system and o the strengthened reinored onrete member. ε e = ε u or ompletely wrapped members ε e = κ v ε u or -sides or 3-sides (U-wrapped) members The bond-redution oeiient shall be omputed rom Equations (19) through (): k k L = 468ε κv 1 e u k k Le = 11,900ε κv u 0.75 (19) (SI Units) 500 L e = ( n t E 0.58 ) 3,300 L e = ( n t E 1 = k ' 4000 ' 7 1 = k k / ) / 3 1 or Completely wrapped d v Le = or U - wrapped d v d v Le or two sides bonded d v (0) (SI Units) (1) (SI Units) () The total shear strength provided by FRP and steel reinorement shall be limited to the ollowing: V + V 8 s s V + V 0.66 ' b d w ' b d w (3) (SI Units) For retangular setions with shear enhanement provided by transverse FRP omposite material, setion orners must be rounded to a radius not less than 3 / 4 inh (0 mm) beore plaement o the FRP omposite material Retangular Wall Setions: Nominal shear strength enhanement or retangular wall setions o depth h parallel to the diretion o applied shear ore, with iber thikness t on both sides o the wall at an angle θ to the members axis, shall be given by V sj = t j h sin θ (4) where j = E j #0.75 uj (or ompletely wrapped on all our sides). Where wall setions have iber bonded to one side only at an angle $ 75 to the member axis, nominal shear strength enhanement shall be taken as V sj = 0.75t j j h sin θ (5) where j = E j # 0.75 uj. Where wall setions have iber bonded to one side at an angle $ 75 degrees to the member axis and with anhorage provided by bonding to the wall ends, the eetive strain used to alulate j shall be determined through ull-sale strutural testing Shear Strength Redution Fator: Dependable shear strength enhanement shall be ound 8

9 by multiplying the nominal shear strength given by Equations (18), (4), or (5), as appropriate, by a shear strength redution ator. Note: These provisions do not apply to shear strength enhanement provided by iber that does not extend the ull setion width bonding to perpendiular aes (setion ends). These provisions do not apply to shear strength enhanement or langed setions requiring plaement o iber around re-entrant orners. These ases must be subjet to speial study. The use o speial anhors attahing the FRP omposite material at the wall edges may be eetive in transerring the design iber stress between wall or beam and iber. 7.4 Quality Control: The quality ontrol douments desribed Setions 6.1 and 6. shall be submitted. 7.5 Nomenlature: A = ross-setional area o onrete in ompression member, in (mm ). A e = ross-setional area o eetively onined onrete setion, in (mm ). A g = gross area o onrete setion, in (mm ). A v = area o FRP shear reinorement with spaing s, in (mm ). AFRP = Aramid iber reinored polymer b = short side dimension o ompression member o non-irular ross setion, in. (mm). b w = web width or diameter o irular setion, in. (mm). d = distane rom extreme ompression iber to entroid o tension reinorement, in. (mm). CFRP = Carbon iber reinored polymer. D = diameter o irular olumns, inhes (mm). d b = reinorement bar diameter, inhes (mm). d v = eetive depth o FRP shear reinorement, in (mm). E = modulus o elastiity o onrete, psi E j E = modulus o elastiity o FRP omposite material, psi E = slope o linear portion o stress-strain model or FRP-onined onrete, psi F = inrease in axial ore, lb (N). = ompressive stress in onrete, psi (MPa) = speiied ompressive strength o onrete, psi = ompressive strength o onined onrete, psi e = eetive stress in the FRP; stress level attained at setion ailure, psi (MPa) N m = speiied ompressive strength o masonry, psi t N = tensile strength o onrete or masonry, psi l = maximum onining pressure due to FRP jaket, psi e = eetive stress in the FRP; stress level attained at setion ailure, psi j = onining strength o FRP omposite material, uj = ultimate tensile strength o omposite material, j = hoop stress developed in jaket material, GFRP = Glass iber reinored polymer. h = long side length o a retangular olumn, inhes (mm). k 1 = modiiation ator applied to κ v to aount or onrete strength. k = modiiation ator applied to κ v to aount or wrapping sheme. L e = ative bond length o FRP laminate, in. l s = reinorement bar splie length, inhes (mm). p = perimeter o raked surae, inhes (mm). p m = ore per unit width that the FRP system transers to the masonry substrate,lb/in (N/m) p sj = volumetri ratio o retroit jaket. M u = bond strength between FRP omposite material and onrete or masonry, psi n = number o plies o FRP reinorement. r = radius o edges o a non-irular ross setion onined with FRP, in. (mm). s = enter-to-enter spaing o FRP shear reinorement, in (mm). t = eetive FRP omposite material thikness. V = shear strength enhanement provided by omposite material, lb (N). V = nominal shear strength provided by onrete with steel lexural reinorement, lb (N). V s = nominal shear strength provided by steel stirrups, lb (N). w = width o FRP reinoring plies, in. (mm). α = angle o iber inlination to member axis, degrees. ε = onrete ompression strain. ε = strain at peak stress or onined onrete. ε u = ultimate ompression strain o unonined onrete. ε u = ultimate ompression strain o onined onrete. 9

10 ε = strain omposite material at designated strength. ε e = eetive strain level in FRP reinorement attained at ailure, in/in (mm/mm). ε d = debonding strain o externally bonded FRP reinorement. ε u = ultimate strain o FRP omposite material. ε t = transition strain in stress-strain urve o FRPonined onrete, in/in (mm/mm) φ = strength redution ator. κ a = eiieny ator or FRP reinorement in determination o (based on geometry o ross setion). κ b = eiieny ator or FRP reinorement in determination o ε u (based on geometry o ross setion). κ v = bond-dependent oeiient or shear. κ ε = eiieny ator equal to 0.55 or FRP strain to aount or the dierene between observed rupture strain in oninement and rupture strain determined rom tensile tests. μ = displaement dutility level, deined relative to yield or raking displaement. ρ g = ratio o area o longitudinal steel reinorement to ross-setional area o a ompression member. ψ = FRP strength redution ator. = 0.85 or lexure (alibrated based on design material properties). 1) = 0.85 or shear (based on reliability analysis) or three-sided FRP U-wrap or two-sided strengthening shemes. = 0.95 or shear ully wrapped setions. Reerened Douments ACI Committee 440.R-08, 008, Guide or the Design and Constrution o Externally Bonded FRP Systems or Strengthening Conrete Strutures, Amerian Conrete Institute, Farmington Hills, MI. ) Conrete Soiety, Design Guidane or Strengthening Conrete Strutures Using Fibre Composite Materials, Tehnial Report No. 55 (TR55), seond edition, Surrey, ) Pessiki, S.; Harries, K. A.; Kestner, J.; Sause, R.; and Riles, J. M., The Axial Behavior o Conrete Conined with Fiber Reinored Composite Jakets, Journal o Composites in Constrution, ASCE, V. 5, No. 4, 001, pp ) Priestley, M.J. Nigel, Frieder Seible and Mihele Calvi, Seismi Design and Retroit o Bridges (Chapters 1 through 8). John Wiley and Sons, In., New York, September 1995, 67 pp. 5) Lam, L., and Teng, J., Design-Oriented Stress-Strain Model or FRP-Conined Conrete, Constrution and Building Materials, V. 17, 003a, pp ) Lam, L., and Teng, J., Design-Oriented Stress-Strain Model or FRP-Conined Conrete in Retangular Columns, Journal o Reinored Plastis and Composites, V., No. 13, 003b, pp ) NSF e, Drinking Water Components Health Eets, NSF International. 10

11 TABLE 1 CREEP RUPTURE STRESS LIMITS IN FRP REINFORCEMENT PARAMETER Fiber Type Stress Type GFRP AFRP CFRP Creep Rupture 0.0 uj 0.30 uj 0.55 uj TABLE PHYSICAL PROPERTIES 6 PROPERTY TEST METHOD NO. OF SPECIMENS 1 Tensile strength ASTM D 3039 Elongation ASTM D Tensile modulus ASTM D 3039 Coeiient o thermal expansion (COE ASTM D 696 or ASTM E CTE) Creep 8 ASTM D Void ontent ASTM D or D Glass transition (Tg) temperature ASTM D 4065 or ASTM E Composite interlaminar shear strength ASTM D Speimen sets shall exhibit a oeiient o variation (COV) o 6 perent or less. Outliers are subjet to urther investigation aording to ASTM E 178. I the COV exeeds 6 perent, the number o speimens shall be doubled. Values shall be determined in the primary and ross (90 ) diretions. 3 Test duration is 3,000 hours, minimum. 4 Maximum void ontent by volume is 6 perent. 5 Minimum 140 F (60 C) Tg is required or ontrol and exposed speimens. 6 For terminology, ASTM E 114 is a reerene. 7 When using ASTM E 831, an Expansion versus Temperature urve as shown in Figure 1 o ASTM E 831 shall be developed; two tangents to the urve shall be plotted to oinide with the straightline portions o the urve above and below the inletion point. The point o intersetion o these tangents shall be reported as Tg or the material. 8 Creep stresses or design shall be the lesser o the analysis o test or the maximum values in Table 1. TABLE 3 ENVIRONMENTAL DURABILITY TEST MATRIX ENVIRONMENTAL DURABILITY TEST RELEVANT SPECIFICATIONS TEST CONDITIONS TEST DURATION Water resistane ASTM D 47 ASTM E perent, 100 ± F 1,000, 3,000 and 10,000 hours Saltwater resistane ASTM D 1141 ASTM C 581 Immersion at 73 ± F 1,000, 3,000 and 10,000 hours Alkali resistane ASTM C 581 Immersion in Ca (CO 3 ) at ph = 9.5 & 73 ± 3 F 1,000 and 3,000 hours Dry heat resistane ASTM D ± 5 F 1,000 and 3,000 hours For SI: C= (t F 3)/1.8. PERCENT RETENTION Hours 1,000 3,

12 FIGURE 1 STRESS-STRAIN DIAGRAM FOR FRP-CONFINED CONCRETE FIGURE EQUIVALENT CIRCULAR CROSSSECTION 14

13 FIGURE 3 TEST SEQUENCE OF IMPOSED DISPLACEMENT 15