1、 2015CODE ANDCOMMENTARYThe complete IBC with commentary after eachsectionVOLUME 2IBC2015 International Building Code CommentaryFirst Printing: March 2015ISBN: 978-1-60983-282-7 (soft-cover edition)COPYRIGHT 2015byINTERNATIONAL CODE COUNCIL, INC.ALL RIGHTS RESERVED. This 2015 International Building C
2、odeCommentaryVolume II is a copyrighted work owned bythe International Code Council, Inc. Without advance written permission from the copyright owner, no part of this book may bereproduced, distributed or transmitted in any form or by any means, including, without limitation, electronic, optical or
3、mechan-ical means (by way of example, and not limitation, photocopying, or recording by or in an information storage retrieval system).For information on permission to copy material exceeding fair use, please contact: Publications, 4051 Flossmoor Road, CountryClub Hills, IL 60478. Phone 1-888-ICC-SA
4、FE (422-7233).Trademarks: “International Code Council,” the “International Code Council” logo and the “International Building Code” are trademarks of the International Code Council, Inc. PRINTED IN THE U.S.A.2015 INTERNATIONAL BUILDING CODECOMMENTARY iiiPREFACEThe principal purpose of the Commentary
5、 is to provide a basic volume of knowledge and facts relating to building constructionas it pertains to the regulations set forth in the 2015 International Building Code. The person who is serious about effectivelydesigning, constructing and regulating buildings and structures will find the Commenta
6、ry to be a reliable data source andreference to almost all components of the built environment.As a follow-up to the International Building Code, we offer a companion document, the International Building CodeCommentaryVolume II. Volume II covers Chapters 16 through 35 of the 2015 International Build
7、ing Code. The basic appealof the Commentary is thus: it provides in a small package and at reasonable cost thorough coverage of many issues likely to bedealt with when using the International Building Code and then supplements that coverage with historical and technicalbackground. Reference lists, i
8、nformation sources and bibliographies are also included.Throughout all of this, effort has been made to keep the vast quantity of material accessible and its method of presentationuseful. With a comprehensive yet concise summary of each section, the Commentary provides a convenient reference forregu
9、lations applicable to the construction of buildings and structures. In the chapters that follow, discussions focus on the fullmeaning and implications of the code text. Guidelines suggest the most effective method of application, and the consequences ofnot adhering to the code text. Illustrations ar
10、e provided to aid understanding; they do not necessarily illustrate the only methodsof achieving code compliance.The format of the Commentary includes the full text of each section, table and figure in the code, followed immediately by thecommentary applicable to that text. At the time of printing,
11、the Commentary reflects the most up-to-date text of the 2015International Building Code. As stated in the preface to the International Building Code, the content of sections in the codewhich begin with a letter designation (i.e., Section F307.1) are maintained by another code development committee.
12、Eachsections narrative includes a statement of its objective and intent, and usually includes a discussion about why the requirementcommands the conditions set forth. Code text and commentary text are easily distinguished from each other. All code text isshown as it appears in the International Buil
13、ding Code, and all commentary is indented below the code text and begins with thesymbol .Readers should note that the Commentary is to be used in conjunction with the International Building Code and not as asubstitute for the code. The Commentary is advisory only; the code official alone possesses t
14、he authority and responsibility forinterpreting the code.Comments and recommendations are encouraged, for through your input, we can improve future editions. Please direct yourcomments to the Codes and Standards Development Department at the Chicago District Office.The International Code Council wou
15、ld like to extend its thanks to the following individuals for their contributions to thetechnical content of this commentary:Brian Black Kevin BrinkmanJohn Woestman Gregory CahaninDavid Cooper Rebecca QuinnDave Collins Joann SurmarVickie Lovell James MilkeJohn Valiulis Richard WalkeMarcelo Hirschler
16、 Dave FrableJeff Hugo Elley KlausbrucknerDick Bukowskiiv 2015 INTERNATIONAL BUILDING CODECOMMENTARYS.I. CONVERSION CHART FOR ENGLISH UNITSEnglish Unit Metric Equivalent1 inch (in.) 25.4 millimeters (mm)1 foot (ft.) 304.8 millimeters (mm)1 square inch (in2) 645.2 square millimeters (mm2)1 square foot
17、 (ft2) 0.093 square meters (m2)1 cubic foot (ft3) 0.028 cubic meters (m3)1 gallon (gal.) .00379 cubic meters (m3)1 gallon (gal.) 3.79 liters (L)1 pound (lb.) 0.454 kilograms (kg)1 ton (T) 0.907 metric ton1 ton (T) 907.2 kilograms (kg)1 pound per square inch (psi) 6.894 kilo- Pascals (kPa)1 pound per
18、 square inch (psi) .0703 kilogram force per square centimeter1 pound per square foot (psf) 47.88 Pascals (Pa)1 pound per square foot (psf) 47.88 Newton per square meter (N/m2)1 foot candle 10.764 lux1 inch water column 248.84 Pascal1 degree 0.01745 radian1 Btu/hr 0.2931 WattTemperature degrees Fahre
19、nheit 1.8 x degrees C + 32.2015 INTERNATIONAL BUILDING CODE COMMENTARY vTABLE OF CONTENTSCHAPTER 16 STRUCTURAL DESIGN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16-1 16-90CHAPTER 17 SPECIAL INSPECTIONS AND TESTS . . . . . . . . . .
20、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17-1 17-28CHAPTER 18 SOILS AND FOUNDATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18-1 18-80CHAPTER 19 CONCRETE . . . . . . . . . . . . . . . . . . . . . . . . . . . .
21、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19-1 19-20CHAPTER 20 ALUMINUM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-1 20-2CHAPTER 21 MASONRY . . . . . . . . . . . . . . . .
22、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21-1 21-40CHAPTER 22 STEEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22-1 22-10CHAPTER 23 WOOD . .
23、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23-1 23-118CHAPTER 24 GLASS AND GLAZING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24-1 24-28C
24、HAPTER 25 GYPSUM BOARD, GYPSUM PANEL PRODUCTS AND PLASTER . . . . . . . . . . . . . . . . . . 25-1 25-24CHAPTER 26 PLASTIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26-1 26-32CHAPTER 27 ELECTRICAL. . . .
25、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27-1 27-4CHAPTER 28 MECHANICAL SYSTEMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28-1 28-2CHAPTER 29 PLUMBIN
26、G SYSTEMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29-1 29-20CHAPTER 30 ELEVATORS AND CONVEYING SYSTEMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30-1 30-26CHAPTER 31 SPECIAL CONSTRUCTION . . .
27、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31-1 31-20CHAPTER 32 ENCROACHMENTS INTO THE PUBLIC RIGHT-OF-WAY . . . . . . . . . . . . . . . . . . . . . . . . . 32-1 32-6CHAPTER 33 SAFEGUARDS DURING CONSTRUCTION . . . . . . . . . . . . . . . . . .
28、. . . . . . . . . . . . . . . . . . . . . . 33-1 33-8CHAPTER 34 RESERVED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34-1 34-2CHAPTER 35 REFERENCED STANDARDS . . . . . . . . . . . . . . . . . . . . . . . . .
29、. . . . . . . . . . . . . . . . . . . . . . . . . . 35-1 35-26APPENDIX A EMPLOYEE QUALIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1 A-2APPENDIX B BOARD OF APPEALS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
30、 . . . . . . . . . . . . . . . . . . . . . . . . . B-1 B-4APPENDIX C GROUP U AGRICULTURAL BUILDINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-1 C-4vi 2015 INTERNATIONAL BUILDING CODE COMMENTARYTABLE OF CONTENTSAPPENDIX D FIRE DISTRICTS. . . . . . . . . . . . . .
31、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-1 D-8APPENDIX E SUPPLEMENTARY ACCESSIBILITY REQUIREMENTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . E-1 E-12APPENDIX F RODENTPROOFING . . . . . . . . . . . . . . . . . . . . . . . . . .
32、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .F-1 F-2APPENDIX G FLOOD-RESISTANT CONSTRUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G-1 G-18APPENDIX H SIGNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
33、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H-1 H-10APPENDIX I PATIO COVERS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .I-1 I-2APPENDIX J GRADING . . . . . . . . . . . . . . . . . .
34、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J-1 J-8APPENDIX K ADMINISTRATIVE PROVISIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . K-1 K-4APPENDIX L EARTHQUAKE RECORDING INSTRUMENTATI
35、ON . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L-1 L-2APPENDIX M TSUNAMI-GENERATED FLOOD HAZARD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M-1 M-4INDEX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
36、 . . . . . . . . . . . . . . . . . . . . . . INDEX-1 INDEX-382015 INTERNATIONAL BUILDING CODE COMMENTARY 16-1SECTION 1601GENERAL1601.1 Scope. The provisions of this chapter shall govern thestructural design of buildings, structures and portions thereofregulated by this code.While a significant porti
37、on of Chapter 16 is dedicatedto the determination of minimum design loads, it alsoincludes other important criteria that impact thedesign of structures, such as the permitted designmethodologies, as well as the combinations of designloads used to establish the required minimumstrength of structural
38、members. Unless stated other-wise, the criteria found in this chapter are applicableto all buildings and structures. See Chapter 34 forapplication of these requirements to alterations, addi-tions or repairs to existing structures.SECTION 1602DEFINITIONS AND NOTATIONS1602.1 Definitions. The following
39、 terms are defined in Chap-ter 2:Definitions facilitate the understanding of code provi-sions and minimize potential confusion. To that end,this section lists definitions of terms associated withstructural design. Note that these definitions arefound in Chapter 2. The use and application ofdefined t
40、erms, as well as undefined terms, are setforth in Section 201.ALLOWABLE STRESS DESIGN.DEAD LOADS.DESIGN STRENGTH.DIAPHRAGM.Diaphragm, blocked.Diaphragm boundary.Diaphragm chord.ESSENTIAL FACILITIES.FABRIC PARTITION.FACTORED LOAD.HELIPAD.ICE-SENSITIVE STRUCTURE.IMPACT LOAD.LIMIT STATE.LIVE LOAD.LIVE
41、LOAD (ROOF).LOAD AND RESISTANCE FACTOR DESIGN (LRFD).LOAD EFFECTS.LOAD FACTOR.LOADS.NOMINAL LOADS.OTHER STRUCTURES.PANEL (PART OF A STRUCTURE).RESISTANCE FACTOR.Chapter 16:Structural DesignGeneral CommentsThis chapter contains the commentary for the followingstructural topics: definitions of structu
42、ral terms, con-struction document requirements, load combinations,dead loads, live loads, snow loads, wind loads, soil lat-eral loads, rain loads, flood loads and earthquake loads.This chapter provides minimum design requirements sothat all buildings and structures are proportioned toresist the load
43、s and forces that are likely to be encoun-tered. The loads specified herein have been establishedthrough research and service performance of buildingsand structures. The application of these loads andadherence to the serviceability criteria will enhance theprotection of life and property. The earthq
44、uake loads,wind loads and snow loads in this chapter are based onthe 2010 edition of ASCE 7. The earthquake criteria andASCE 7 load requirements are based on the NationalEarthquake Hazards Reduction Programs (NEHRP)Recommended Provisions for Seismic Regulations forNew Buildings and Other Structures
45、(FEMA 450). TheNEHRP provisions were prepared by the Building Seis-mic Safety Council (BSSC) for the Federal EmergencyManagement Agency (FEMA).PurposeThe purpose of this chapter is to prescribe minimumstructural loading requirements for use in the designand construction of buildings and structures w
46、ith theintent to minimize hazard to life and improve the occu-pancy capability of essential facilities after a designlevel event or occurrence.STRUCTURAL DESIGN16-2 2015 INTERNATIONAL BUILDING CODE COMMENTARYRISK CATEGORY.STRENGTH, NOMINAL.STRENGTH, REQUIRED.STRENGTH DESIGN.SUSCEPTIBLE BAY.VEHICLE B
47、ARRIER.NOTATIONS.D=Dead load.Di= Weight of ice in accordance with Chapter 10 of ASCE7.E=Combined effect of horizontal and vertical earthquakeinduced forces as defined in Section 12.4.2 of ASCE7.F=Load due to fluids with well-defined pressures andmaximum heights.Fa= Flood load in accordance with Chap
48、ter 5 of ASCE 7.H=Load due to lateral earth pressures, ground waterpressure or pressure of bulk materials.L=Roof live load greater than 20 psf (0.96 kN/m2) andfloor live load.Lr= Roof live load of 20 psf (0.96 kN/m2) or less.R=Rain load.S=Snow load.T=Self-straining load.Vasd= Nominal design wind spe
49、ed (3-second gust), miles perhour (mph) (km/hr) where applicable.Vult= Ultimate design wind speeds (3-second gust), milesper hour (mph) (km/hr) determined from Figure1609.3(1), 1609.3(2), 1609.3(3) or ASCE 7.W=Load due to wind pressure.Wi= Wind-on-ice in accordance with Chapter 10 of ASCE7.These notations are used to refer to specific nominalloads that are determined in this chapter for use inthe load combinations in Section
