1、ACI 352R-02 supersedes ACI 352R-91(Reapproved 1997) and became effectiveJune 18, 2002.Copyright 2002, American Concrete Institute.All rights reserved including rights of reproduction and use in any form or by anymeans, including the making of copies by any photo process, or by electronic ormechanica
2、l device, printed, written, or oral, or recording for sound or visual reproduc-tion or for use in any knowledge or retrieval system or device, unless permission inwriting is obtained from the copyright proprietors.1ACI Committee Reports, Guides, Manuals, and Commentariesare intended for guidance in
3、planning, designing, executing,and inspecting construction. This document is intended for theuse of individuals who are competent to evaluate thesignificance and limitations of its content and recommendationsand who will accept responsibility for the application of thematerial it contains. The Ameri
4、can Concrete Institute disclaimsany and all responsibility for the stated principles. The Instituteshall not be liable for any loss or damage arising therefrom.Reference to this document shall not be made in contractdocuments. If items found in this document are desired by theArchitect/Engineer to b
5、e a part of the contract documents, theyshall be restated in mandatory language for incorporation bythe Architect/Engineer.Recommendations for Design ofBeam-Column Connections inMonolithic Reinforced Concrete StructuresReported by Joint ACI-ASCE Committee 352ACI 352R-02(Reapproved 2010)Recommendatio
6、ns are given for member proportions, confinement of thecolumn core in the joint region, control of joint shear stress, ratio of column-to-beam flexural strength at the connection, development of reinforcingbars, and details of columns and beams framing into the joint. Normal typeis used for recommen
7、dations. Commentary is provided in italics to amplifythe recommendations and identify available reference material.The recommendations are based on laboratory testing and field studiesand provide a state-of-the-art summary of current information. Areas needingresearch are identified. Design examples
8、 are presented to illustrate the useof the design recommendations.Keywords: anchorage; beam; beam-column; bond; columns; confinedconcrete; high-strength concrete; joints; reinforced concrete; reinforce-ment; reinforcing steel; shear strength; shear stress.CONTENTSChapter 1Introduction, scope, and de
9、finitions,p. 21.1Introduction1.2Scope1.3DefinitionsChapter 2Classification of beam-column connections, p. 32.1Loading conditions2.2Connection geometryChapter 3Design considerations, p. 33.1Design forces and resistance3.2Critical sections3.3Member flexural strength3.4ServiceabilityChapter 4Nominal st
10、rength and detailing requirements, p. 64.1Column longitudinal reinforcement4.2Joint transverse reinforcement4.3Joint shear for Type 1 and Type 2 connections4.4Flexure4.5Development of reinforcement4.6Beam transverse reinforcementChapter 5Notation, p. 17Chapter 6References, p. 176.1Referenced standar
11、ds and reports6.2Cited referencesJames R. Cagley Theodor Krauthammer Donald F. Meinheit Bahram M. ShahroozMarvin E. Criswell Michael E. Kreger*Jack P. Moehle John W. WallaceCatherine E. French James M. LaFave*Stavroula J. Pantazopoulou James K. WightLuis E. Garca Douglas D. Lee Patrick Paultre Lorin
12、g A. Wyllie, Jr.T. Russell Gentry*Roberto T. Leon M. Saiid Saiidi*Member of editorial subcommittee.Chair of editorial subcommittee.John F. Bonacci*ChairSergio M. AlcocerSecretary2 BEAM-COLUMN CONNECTIONS IN MONOLITHIC CONCRETE STRUCTURES (ACI 352R-02)American Concrete Institute Copyrighted Materialw
13、ww.concrete.orgAppendix AAreas needing research, p. 20A.1Effect of eccentric beams on jointsA.2Lightweight aggregate concrete in jointsA.3Limit on joint shearA.4Behavior of indeterminate systemsA.5Distribution of plastic hingesA.6Innovative joint designsA.7Special joint configurations and loadingsA.
14、8Joints in existing structuresAppendix BDesign examples, p. 21CHAPTER 1INTRODUCTION, SCOPE,AND DEFINITIONS1.1IntroductionThese recommendations are for determining proportions,design, and details of monolithic beam-column connectionsin cast-in-place concrete frame construction. The recommenda-tions a
15、re written to satisfy strength and ductility require-ments related to the function of the connection within astructural frame.This report considers typical beam-column connections incast-in-place reinforced concrete buildings, as shown inFig. 1.1. Although the recommendations are intended toapply pr
16、imarily to building structures, they can be extendedto other types of frame structures when similar loading andstructural conditions exist. Design examples illustrating theuse of these recommendations are given in Appendix B.Specifically excluded from these recommendations areslab-column connections
17、, which are the topic of ACI 352.1R,and precast structures where connections are made near thebeam-to-column intersection.The material presented herein is an update of a previousreport from ACI 352R. Research information available inrecent references and Chapter 21 of ACI 318-02 wasreviewed during t
18、he updating of these provisions. Modificationshave been made to include higher-strength concrete, slab-steel contribution to joint shear, roof-level connections,headed reinforcement used to reduce steel congestion,connections in wide-beam systems, and connections witheccentric beams. This report add
19、resses connections in bothseismic and nonseismic regions, whereas Chapter 21 of ACI318-02 only addresses connections for seismic regions. Anumber of recommendations from previous editions of thisreport have been adopted in Chapter 21 of ACI 318-02 forseismic design. Recommendations in this report fo
20、rconnections in earthquake-resisting structures areintended to complement those in the 1999 edition of Chapter21 of ACI 318, covering more specific connection types andproviding more detail in some instances.In many designs, column sizes may be defined by the require-ments of the connection design.
21、Attention is focused on theconnection to promote proper structural performance under allloading conditions that may reasonably be expected to occurand to alert the designer to possible reinforcement congestion.1.2ScopeThese recommendations apply only to structures usingnormalweight concrete with a c
22、ompressive strength fc notexceeding 15,000 psi (100 MPa) in the connections.From consideration of recent research results of connec-tions with concrete compressive strengths of up to 15,000 psi(100 MPa), ACI Committee 352 has extended the limits of therecommendations to include high-strength concret
23、e (Guima-raes, Kreger, and Jirsa 1992; Saqan and Kreger 1998; Suganoet al. 1991). The committee believes that further researchdemonstrating the performance and design requirements ofFig. 1.1Typical beam-to-column connections (slabs not shown for clarity). Wide-beamcases not shown.BEAM-COLUMN CONNECT
24、IONS IN MONOLITHIC CONCRETE STRUCTURES (ACI 352R-02) 3American Concrete Institute Copyrighted Materialwww.concrete.orgconnections with lightweight-aggregate concrete is requiredbefore the scope of these recommendations can extend beyondnormalweight concrete. These recommendations are appli-cable to
25、structures in which mechanical splices are used,provided that the mechanical splices meet the requirements ofSection 21.2.6 of ACI 318-02 and the recommendations of theCommentary to Section 21.2.6 of ACI 318-02.1.3DefinitionsA beam-column joint is defined as that portion of thecolumn within the dept
26、h of the deepest beam that frames intothe column. Throughout this document, the term joint is usedto refer to a beam-column joint.A connection is the joint plus the columns, beams, and slabadjacent to the joint.A transverse beam is one that frames into the joint in adirection perpendicular to that f
27、or which the joint shear isbeing considered.CHAPTER 2CLASSIFICATION OF BEAM-COLUMN CONNECTIONS2.1Loading conditionsStructural connections are classified into two categoriesType 1 and Type 2based on the loading conditions for theconnection and the anticipated deformations of theconnected frame member
28、s when resisting lateral loads.2.1.1 Type 1A Type 1 connection is composed ofmembers designed to satisfy ACI 318-02 strength require-ments, excluding Chapter 21, for members without signifi-cant inelastic deformation.2.1.2 Type 2In a Type 2 connection, frame members aredesigned to have sustained str
29、ength under deformationreversals into the inelastic range.The requirements for connections are dependent on themember deformations at the joint implied by thedesign-loading conditions.Type 1 is a moment-resisting connection designed on thebasis of strength in accordance with ACI 318-02, excludingCha
30、pter 21.Type 2 is a connection that has members that are requiredto dissipate energy through reversals of deformation into theinelastic range. Connections in moment-resisting framesdesigned according to ACI 318-02 Sections 21.2.1.3 and21.2.1.4 are of this category.2.2Connection geometry2.2.1 These r
31、ecommendations apply when the design beamwidth bbis less than the smaller of 3bc and (bc+ 1.5hc), wherebcand hcare the column width and depth, respectively.Classification of connections as interior, exterior, orcorner connections is summarized in Fig. 1.1. The recom-mendations provide guidance for c
32、ases where the beam barsare located within the column core and for cases wherebeam width is larger than column width, requiring somebeam bars to be anchored or to pass outside the columncore. Connections for which the beam is wider than thecolumn are classified as wide-beam connections. Test results
33、have given information on the behavior of Type 2 interior(four beams framing into the column) and exterior (threebeams framing into the column) wide beam-column connec-tions (Gentry and Wight 1992; Hatamoto, Bessho, andMatsuzaki 1991; Kitayama, Otani, and Aoyama 1987;Kurose et al. 1991; LaFave and W
34、ight 1997; Quintero-Febres and Wight 1997). The maximum beam width allowedrecognizes that the effective wide beam width is more closelyrelated to the depth of the column than it is to the depth of thewide beam. The limit is intended to ensure the completeformation of a beam plastic hinge in Type 2 c
35、onnections.2.2.2 These recommendations apply to connections whenthe beam centerline does not pass through the columncentroid, but only when all beam bars are anchored in or passthrough the column core.Eccentric connections having beam bars that pass outsidethe column core are excluded because of a l
36、ack of researchdata on the anchorage of such bars in Type 2 connectionsunder large load reversals.CHAPTER 3DESIGN CONSIDERATIONS3.1Design forces and resistanceAll connections should be designed according to Chapter4 for the most critical combination that results from the inter-action of the multidir
37、ectional forces that the memberstransmit to the joint, including axial load, bending, torsion,and shear. These forces are a consequence of the effects ofexternally applied loads and creep, shrinkage, temperature,settlement, or secondary effects.The connection should resist all forces that may be tra
38、ns-ferred by adjacent members, using those combinations thatproduce the most severe force distribution at the joint,including the effect of any member eccentricity. Forcesarising from deformations due to time-dependent effects andtemperature should be taken into account. For Type 2connections, the d
39、esign forces that the members transfer tothe joint are not limited to the forces determined from afactored-load analysis, but should be determined from theprobable flexural strengths of the members as defined inSection 3.3 without using strength-reduction factors.3.2Critical sectionsA beam-column jo
40、int should be proportioned to resist theforces given in Section 3.1 at the critical sections. The criticalsections for transfer of member forces to the connection are atthe joint-to-member interfaces. Critical sections for shear forceswithin the joint are defined in Section 4.3.1. Critical sections
41、forbars anchored in the joint are defined in Section 4.5.1.Design recommendations are based on the assumptionthat the critical sections are immediately adjacent to thejoint. Exceptions are made for joint shear and reinforcementanchorage. Figure 3.1 shows the joint as a free body withforces acting on
42、 the critical sections.3.3Member flexural strengthBeam and column flexural strengths are computed forestablishing joint shear demand (Section 3.3.4) and forchecking the ratio of column-to-beam flexural strength ateach connection (Section 4.4).4 BEAM-COLUMN CONNECTIONS IN MONOLITHIC CONCRETE STRUCTUR
43、ES (ACI 352R-02)American Concrete Institute Copyrighted Materialwww.concrete.org3.3.1 For Type 1 connections, beam flexural strengthshould be determined by considering reinforcement in thebeam web plus any flange reinforcement in tension in accor-dance with Section 10.6.6 of ACI 318-02.3.3.2 For Typ
44、e 2 connections, wherever integrally castslab elements are in tension, beam flexural strength shouldbe determined by considering the slab reinforcement withinan effective flange width, be, in addition to beam longitu-dinal tension reinforcement within the web. Forces intro-duced to the joint should
45、be based on beam flexural strengthconsidering the effective slab reinforcement contribution fornegative bending moment (slab in tension). Slab reinforcementshould be considered to act as beam tension reinforcementhaving strain equal to that occurring in the web at the depth ofthe slab steel. Only co
46、ntinuous or anchored slab reinforcementshould be considered to contribute to the beam flexural strength.Except for the case of exterior and corner connectionswithout transverse beams, the effective tension flange widthbeshould be taken the same as that prescribed in ACI 318-02for flanges in compress
47、ion. Section 8.10.2 of ACI 318-02should be used for beams with slabs on both sides. Section8.10.3 of ACI 318-02 should be used for beams with slabs onone side only. The effective slab width should not be takenless than 2bb, where bbis the web width of the beam.In the case of exterior connections wit
48、hout transversebeams, slab reinforcement within an effective width 2ct+ bccentered on the column should be considered to contribute tothe flexural strength of the beam with tension flange(s).For corner connections without transverse beams, theeffective slab width beshould be taken as (ct+ bc) plus t
49、hesmaller of ctand the perpendicular distance from the sideface of the column to the edge of the slab parallel to the beam.The quantity ctis a width of slab in the transverse directionequal to the distance from the interior face of the column tothe slab edge measured in the longitudinal direction, but notexceeding the total depth of the column in the longitudinaldirection hc. The effective slab width for exterior and cornerconnections without transverse beams need not be taken asmore than 1/12 of the span length of the beam.Numerous stu