1、18Steel Design GuideSteel-Framed Open-Deck Parking Structures18Steel Design GuideSteel-Framed Open-Deck Parking Structures CHARLES H. CHURCHESStructural EngineerChurches Consulting EngineersWashington, Pennsylvaniawith additional material contributed byEMILE W.J. TROUPStructural Steel Fabricators of
2、 New EnglandCanton, MassachusettsCARL ANGELOFFManager/Market DevelopmentBayer CorporationPittsburgh, PennsylvaniaAMERICAN INSTITUTE OF STEEL CONSTRUCTION, INC.Copyright 2003byAmerican Institute of Steel Construction, Inc.All rights reserved. This book or any part thereofmust not be reproduced in any
3、 form without thewritten permission of the publisher.The information presented in this publication has been prepared in accordance with recognizedengineering principles and is for general information only. While it is believed to be accurate,this information should not be used or relied upon for any
4、 specific application without com-petent professional examination and verification of its accuracy, suitablility, and applicabilityby a licensed professional engineer, designer, or architect. The publication of the material con-tained herein is not intended as a representation or warranty on the par
5、t of the AmericanInstitute of Steel Construction or of any other person named herein, that this information is suit-able for any general or particular use or of freedom from infringement of any patent or patents.Anyone making use of this information assumes all liability arising from such use.Cautio
6、n must be exercised when relying upon other specifications and codes developed by otherbodies and incorporated by reference herein since such material may be modified or amendedfrom time to time subsequent to the printing of this edition. The Institute bears no responsi-bility for such material othe
7、r than to refer to it and incorporate it by reference at the time of theinitial publication of this edition.Printed in the United States of AmericaFirst Printing: January 2004vPreface AcknowledgementsThis design guide is specifically focused on structural engi-neering issues in the design of open-de
8、ck parking struc-tures and does not deal in depth with parking usage orgeometric topics. General parking topics and their imple-mentation in steel-framed parking structures are covered ina separate publication, Innovative Solutions in Steel: Open-Deck Parking Structures(formerly titled ADesign Aid f
9、orOpen-Deck Steel-Framed Parking Structures), also pub-lished by the American Institute of Steel Construction. This design guide approaches the development of steel-framed parking structures in the same sequence as adesigner would approach the design development. For thisreason, the discussion of th
10、e steel framing system isdeferred until after the section dealing with deck selection.The issues discussed in this design guide are: Deck Systems Framing Systems Mixed Use Structures Fire Protection Requirements Barriers and Facades Stairs and Elevators Corrosion Protection Structural MaintenanceAIS
11、C would like to thank the following people for assis-tance in the production and review of this design guide.Their comments and suggestions have been invaluable.Rashid AhmedEdmund BaumTom CalzoneCharles CarterWilliam CorbettJohn BakotaJohn CrossThomas FaraoneChristopher HewittKenneth HillerScott Ken
12、nedyGerald Loberger, Jr.Billy MilliganWilliam PascoliKimberly RobinsonLen Tsupros Gail VasonisMichael WestviTable of ContentsChapter 1Introduction 11.1 Overview of Open-Deck Parking Structures11.2 Major Components of Interest to a Structural Engineer11.3 Code Considerations 11.3.1 Code Applicability
13、11.3.2 Relevant Code Sections for Open-Deck Parking Structures21.3.3 Code Definitions 21.3.4 Fire Protection and Height21.3.5 ADAGuidelines3Chapter 2Deck Systems for Parking Structures 52.1 Types of Deck Systems 52.1.1 Cast-in-place reinforced concrete62.1.1.1 Clear Cover and Permeability 62.1.1.2 C
14、uring72.1.1.3 Joints, Cracks and Drainage72.1.1.4 Steel Deck82.1.2 Cast-in-Place Post-Tensioned Slabs and Toppings92.1.3 Precast Double Tees92.1.4 Other Systems 102.1.4.1 Filigree102.1.4.2 Hollow-Core Plank102.2 Deck System Selection by Climactic Zone102.3 Concrete Durability102.4 Plaza Deck Systems
15、122.5 Deck System Design Parameters132.5.1 Cast-in-Place Conventionally Reinforced Concrete on Stay-in-Place Metal Forms 132.5.1.1 Deck Slope142.5.2 Cast-in-Place Post-Tensioned Slabs and Toppings142.5.3 Precast Double Tees152.5.4 Filigree Precast with Post-Tensioned Deck152.5.5 Filigree Precast wit
16、h Conventionally Reinforced Slab162.5.6 Precast Hollow Core Slabs with Field Topping 162.5.7 Deck Renovation16Chapter 3Framing Systems173.1 Introduction 173.2 Economy173.2.1 Relationship Between Deck Type and Bay Size Geometry 173.3 Plan Framing Design183.3.1 Cast-in-Place Conventionally Reinforced
17、Slab Poured on Stay-in-Place Metal Decking 183.3.2 Cast-in-Place Post-Tensioned Slab Framing Plan183.3.2.1 The Effect That Post-Tensioning Forces Have on Members and Their Connection183.3.2.2 Construction Loads193.3.2.3 Camber193.3.2.4 Connection Design193.3.2.5 Member Design in Direction of Primary
18、 Reinforcing19vii3.3.3 Precast Double Tee Deck193.3.4 Cast-in-Place Post Tensioned Slab on Filigree Forms 203.3.5 Cast-in-Place Conventionally Reinforced Slab on Precast Forms 203.4 Other Framing Considerations203.4.1 Connection Type: Rigid or Semi-Rigid203.4.2 Composite Beams 203.4.3 Shored Versus
19、Un-Shored Composite Beams213.4.3.1 Cast-in-Place Post-Tensioned Deck213.4.3.2 Cast-in-Place Slab on Metal Deck213.4.3.3 Cast-in-Place Slab on a Filigree Deck213.4.4 Non-Composite Beams 213.4.5 Castellated Beams213.4.6 Perimeter Beams 213.4.7 Steel Joists223.4.8 Control/Expansion Joints223.5 Vertical
20、 Framing Design 223.5.1 Lateral Load Considerations223.5.2 Braced Frames223.5.2.1 Length Changes Due to Thermal Effects233.5.2.2 Shortening of the Deck Due to Concrete Shrinkage and Creep 233.5.2.3 Length Changes and How They Relate to Bracing233.5.3 Shear Walls 233.6 Erection Considerations243.6.1
21、Considerations for All Steel-Framed Parking Structures 243.6.2 Considerations for Deck-Specific Types24Chapter 3 Tables25Chapter 3 Figures33Chapter 4Mixed-Use Structures 63Chapter 5Fire Protection Requirements65Chapter 6Barriers and Facades676.1 Impact Requirements676.2 Railing Code Requirements676.
22、3 Facade Options676.4 Perimeter Protection676.4.1 Precast Architectural Panels686.4.2 Open Steel Member Design686.4.3 Cable Barrier Design Calculations 68Chapter 7Stairs and Elevators717.1 Stair Locations and Requirements717.2 Elevators71Chapter 8Corrosion Protection for Exposed Steel in Open-Deck P
23、arking Structures 778.1 General Overview 778.2 Environmental Factors77viii8.3 High-Performance Coating Systems 778.3.1 Overview 778.3.2 Selection788.3.2.1 Factors That Affect Cost and Performance 788.3.2.2 Recommended Coating Systems 798.3.2.3 Moderate Performance Coating Systems818.3.2.4 Low-VOC Al
24、ternative 818.4 Galvanizing 81Chapter 9Life-Cycle Costs of Steel-Framed Parking Structures83Chapter 10Checklist for Structural Inspection of Parking Structures85AppendixA1Example: Post-Tensioned Deck Parking Garage 87AppendixA2Example:Cast-in-Place Concrete on Metal Deck 95AppendixA3Example: Precast
25、Twin Tee Deck 101AppendixBProtective Coating System Specification 103AppendixCBibliography of Technical Information on Painting111AppendixDRecommended Resources on Parking Structures 113DESIGN GUIDE 18 / STEEL-FRAMED OPEN-DECK PARKING STRUCTURES /11.1 Overview of Open-Deck Parking StructuresSteel-fr
26、amed parking structures are increasing in popularity.The recent trend toward steel has prompted industry analystDale Denda of the Parking Market Research Company tocomment that “exposed steel-frame construction is back asa recognized option for multi-story parking structures.“(Parking Today, June 20
27、01)Recent advances in coating technologies and designinnovations need to be evaluated and considered for theparking structure. In addition, the structural engineer needsto be able to intelligently evaluate the merits of variousframing systems in order to provide professional guidanceto garage owners
28、 and other members of the project team.Today, owners and architects are choosing steel framingsystems for their lower construction costs, reduced life-cycle costs, rapid construction, long term durability and aclean, open feel conducive to personal security. It falls tothe structural engineer to opt
29、imize these benefits in the finaldesign by taking advantage of high-performance coatings,innovative structural techniques, reduced structure weight(often at least 20 percent) and enhanced seismic perform-ance.Todays parking structure framing systems primarily fallinto three categories: Cast-in-place
30、 concrete framing supporting a post-ten-sioned concrete deck Precast/Prestressed concrete framing supporting precastdouble tees Fabricated structural steel framing supporting a post-ten-sioned cast-in-place, conventionally reinforced concretedeck on stay-in-place metal form or precast deckOther deck
31、 systems have been utilized in various areas ofthe country including concrete filigree panels (a precastpanel form system) and short-span reinforced concrete onremovable forms. Structural steel framing has been used tosupport all of these types of concrete deck systems. Thisallows the structural des
32、igner to choose the optimal decksystem for a given project and still enjoy the benefits of asteel framing system.1.2 MajorComponents of Interest to a StructuralEngineerIn order to effectively design an open-deck steel-framedparking structure the structural engineer will need to evalu-ate a number of
33、 issues. These include: Relevant provisions of the governing building code forthe location of the parking structure The geometry of the parking stalls as a function of opti-mum bay sizing The possible configuration of ramp systems to allow forsmooth traffic flow within the parking structure These th
34、ree design components are introduced and dis-cussed as part of the general parameters affecting parkingdesign in a separate publication, Innovative Solutions inSteel: Open-Deck Parking Structures (formerly titled ADesign Aid for Open-Deck Steel-Framed Parking Struc-tures), also published by the Amer
35、ican Institute of SteelConstruction. They are summarized in this introductorysection as they impact structural design.Nine components of the structural design process havebeen identified and a separate section has been allocated toeach. These are: Deck Systems Framing Systems Mixed-Use Structures Fi
36、re Protection Requirements Barriers and Facades Stairs and Elevators Corrosion Protection Structural MaintenanceFour appendices are included that provide design exam-ples, additional resources relating to high-performancecoating systems, discussion of the benefits of steel-framedparking structures a
37、nd additional resources for the designerof a parking structure.1.3 Code Considerations1.3.1 Code ApplicabilityOver the past several decades designers have been facedwith a variety of differing building codes based on the loca-tion of the constructed project. Variations existed betweenmodel building
38、codes and local jurisdictions within areas ofadoption of model building codes. The International CodeChapter 1Introduction2 / DESIGN GUIDE 18 / STEEL-FRAMED OPEN-DECK PARKING STRUCTURESCouncil released the International Building Code in 2000,consolidating three previously separate and regional model
39、building codes: the BOCA National Building Code, theICBO Uniform Building Code, and the SBCCI SouthernBuilding Code. In 2002, the National Fire Protection Asso-ciation released NFPA 5000 as an alternative model build-ing code. NFPA 5000 (Section 6.4.2.55) specifies that alltypes of parking structure
40、s conform to NFPA88A. Design-ers should verify which model building code and what localamendments are applicable for a planned parking structure.1.3.2 Relevant Code Sections forOpen-Deck ParkingStructuresFor a listing of the relevant code sections for open-deckparking structures, see Table 1-1.1.3.3
41、 Code DefinitionsCare must be taken in understanding the provision of thecodes based on the definition of certain terms. Theseinclude:Height. The IBC defines the height of a parking struc-ture as the vertical distance from the grade plane to thehighest roof surface.Openness. The IBC defines required
42、 openness for aparking structure as having uniformly distributed open-ings on two or more sides of the structure comprising atleast 20 percent of the total perimeter wall area of eachtier and the aggregate length of the openings should con-stitute a minimum of 40 percent of the perimeter of thetier.
43、 NFPAdefines openness as having distributed open-ings to the atmosphere of not less than 1.4 ft2for eachlinear foot of its exterior perimeter. The openings shouldbe uniformly distributed over 40 percent of the perime-ter or uniformly over two opposing sides.1.3.4 Fire Protection and HeightCurrently,
44、 model building codes do not require fire protec-tion for structural steel members in an open-deck parkingstructure less than 75 ft in height as long as any point on anyparking tier is within 200 ft of an open side. It should benoted that the height of a parking structure is measured tothe top of th
45、e deck for the top parking tier, not to the top ofany facades or parapet walls (this is based on the treatmentof the top tier as the “roof“ of the parking structure withparking allowed on the roof). It is possible for a steel-framed parking structure toexceed the 75-ft limitation based on the square
46、 footage ofeach tier and the number of open sides, although parkingstructures seldom attain this height for operational reasons.Table 1-2 presents the parameters used in determining max-imum height and tier area under both the NFPA BuildingCode and International Building Code. The prospectiveowner o
47、f a parking structure should consult with the localbuilding code official to determine any local modificationsof the relevant code provisions.Topic IBC NFPA 88A Structure Classification 406.3.3.1 3.3.2.2 Clear Height 406.2.3 Guards 406.2.4 Vehicle Barriers 406.2.5 Vehicle Ramps 406.2.6 Floor Surface
48、 406.2.7 4.3 406.3.4 Mixed Use Separation 406.2.7 4.1.2 406.3.4 4.1.4 30.8.1.2 (NFPA 5000) Area and Height 406.3.5 4.7.3 406.3.6 Sprinkler Systems 406.3.10 Prohibitions 406.3.13 Design Loads ASCE 7-98 Table 4-1 Load Reductions 1607.9.1 Table 1-1 Relevant Code Sections for Open-Deck Parking Structure
49、sDESIGN GUIDE 18 / STEEL-FRAMED OPEN-DECK PARKING STRUCTURES /3When evaluating tier area and structure height, theimpact of any future vertical expansion should be taken intoaccount.When parking is being provided on the lower floors of amixed-use structure, the lower parking floors must be fireseparated from the upper floors and fire rated.1.3.5 ADAGuidelinesThe Americans with Disabilities Act establishes designguidelines for addressing the needs of persons with disabil-ities to access all newly constructed structures. CurrentADAguidel
