ufc_3_301_01_2019.pdf

UFC 3-301-01

1 October 2019

UNIFIED FACILITIES CRITERIA (UFC)

STRUCTURAL ENGINEERING

APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED

STRUCTURAL ENGINEERING

Any copyrighted material included in this UFC is identified at its point of use.

Use of the copyrighted material apart from this UFC must have the permission of the copy-right holder.

U.S. ARMY CORPS OF ENGINEERS

NAVAL FACILITIES ENGINEERING COMMAND (Preparing Activity)

AIR FORCE CIVIL ENGINEER CENTER

This UFC supersedes UFC 3-301-01, dated 1 June 2013 with Change 4 of 12 September 2016.

UFC 1-300-01

FOREWORD

The Unified Facilities Criteria (UFC) system is prescribed by MIL-STD 3007, including the ex-emption process, and provides planning, design, construction, sustainment, restoration, and modernization criteria, and applies to the Military Departments, the Defense Agencies, and the DoD Field Activities in accordance with USD (AT&L) Memorandum dated 29 May 2002. UFC will be used for all DoD projects and work for other customers where appropriate. All construc-tion outside of the United States is also governed by Status of Forces Agreements (SOFA), Host Nation Funded Construction Agreements (HNFA), and in some instances, Bilateral Infra-structure Agreements (BIA.) Therefore, the acquisition team must ensure compliance with the most stringent of the UFC, the SOFA, the HNFA, and the BIA, as applicable.

UFC are living documents and will be periodically reviewed, updated, and made available to us-ers as part of the Services’ responsibility for providing technical criteria for military construction.

Headquarters, U.S. Army Corps of Engineers (HQUSACE), Naval Facilities Engineering Com-mand (NAVFAC), and Air Force Civil Engineer Center (AFCEC) are responsible for administra-tion of the UFC system. Military Departments, the Defense Agencies, and the DoD Field Activi-ties should contact the preparing service for document interpretation and improvements. Tech-nical content of this UFC is the responsibility of the DoD structural working group. Recom-mended changes with supporting rationale should be sent to the respective service proponent office by the following electronic form: Criteria Change Request. The form is also accessible from the Internet sites listed below.

UFC are effective upon issuance and are distributed only in electronic media from the following source:

• Whole Building Design Guide web site http://dod.wbdg.org/.

Refer to UFC 1-200-01, DoD Building Code (General Building Requirements), for implementa-tion of new issuances on projects.

AUTHORIZED BY:

George O. Lea Jr P.E. CCM FCMAA ROBERT D. CURFMAN, P.E.

Chief Military Engineering Branch Chief Engineer Engineering and Construction Divi-sion US Army Corps of Engineers

Naval Facilities Engineering Command

NANCY J. BALKUS,, P.E., SES MICHAEL McANDREW Deputy Director of Civil Engineers DCS Logistics, Engineering & Force Protection (HAF/A4C) HQ, United States Air Force

Deputy Assistant Secretary of Defense (Facilities Management) Office of the Assistant Secretary of Defense (Sustainment) i

REVISION SUMMARY SHEET

Subject: UFC 3-301-01, Structural Engineering

Cancels: UFC 3-301-01, Structural Engineering dated 1 June 2013 with Change 3 of 12 September 2016

Description of Changes:

• This UFC combines UFC 3-301-01, Structural Engineering, and all provi-sions of UFC 3-310-04, Seismic Design for Buildings, that do not relate to Risk Category V structures, strategic military assets. UFC 3-301-02 now ap-plies strictly to Risk Category V structures only.

• This UFC adopts the structural design provisions of the 2018 International Building Code (2018 IBC) for use in DoD building design and renovation.

• This UFC adopts the structural design provisions of the 2018 International Existing Building Code (2018 IEBC).

• Additional design load combinations are now specified for the design of structural members sensitive to vertical earthquake ground motion.

• Live loads are updated to coordinate with 2018 IBC.

• This UFC adopts the structural design provisions of the 2016 Minimum De-sign Loads for Buildings and Other Structures (ASCE 7-16).

• Site-specific structural load data tables for wind are updated to the basic wind speed values from the 2018 IBC and ASCE/SEI 7-16.

• Site-specific structural load data tables for seismic ground motion parame-ters are updated to the risk-targeted maximum considered earthquake val-ues and the peak ground accelerations from ASCE/SEI 7-16.

• Updated snow, wind and seismic load tables are no longer part of this UFC;

they can be found using the structural load data tool hosted on the Whole Building Design Guide website at:

https://www.wbdg.org/additional-resources/tools/ufcsldt

Reasons for Changes:

• The updated UFC is designed to be consistent with and to supplement the guidance contained in the 2018 IBC as modified and implemented by UFC 1- 200-01.

Impact:

The newly introduced design load combinations for structural members sensitive to ver-tical ground motions may result in modest increases in the cost of those members.

However, the seismic performance of these members should improve.

ii

The following additional benefit should be realized:

• Web based load calculating tool ensures that the locations identified and the loadings described are complete and current with the most up-to-date availa-ble information.

• DoD structural design criteria is current with industry codes and standards.

Non-Unified Items: This document contains no non-unified items

TABLE OF CONTENTS

INTRODUCTION

MODIFICATIONS TO IBC

iii

CHAPTER 3 MODIFICATIONS TO ASCE 7

iv v

CHAPTER 4 SEISMIC EVALUATION AND RETROFIT OF EXISTING BUILDINGS .. 61

CHAPTER 5 NONBUILDING STRUCTURES

CHAPTER 6 MODIFICATIONS TO THE IBC FOR CRITICAL HEALTHCARE

FACILITIES

vi

CHAPTER 7 MODIFICATIONS TO ASCE 7-16 FOR CRITICAL HEALTHCARE

FACILITIES

CHAPTER 8 MODIFICATIONS TO IEBC

vii

APPENDIX A REFERENCES

APPENDIX B BEST PRACTICES

APPENDIX C ALTERNATE DESIGN PROCEDURE FOR RC IV STRUCTURES

viii ix

APPENDIX D GUIDANCE FOR SEISMIC DESIGN OF NONSTRUCTURAL

COMPONENTS

x

APPENDIX E MECHANICAL AND ELECTRICAL COMPONENT CERTIFICATION 149

APPENDIX F ABBREVIATIONS

APPENDIX G MINIMUM UNIFORMLY DISTRIBUTED LIVE LOADS, LO, AND

MINIMUM CONCENTRATED LIVE LOADS

FIGURES

Widths of Thickened Slabs and Slab Edge Conditions Under Wall Loads

Anchorage of Walls to Flexible Diaphragm Figure B-1 Design Depth of Bottom of Building Foundation Figure D-1 Partial Infill Masonry Wall between Two Concrete Columns, Causing

Adverse “Short Column” Effect Figure D-2 Typical Details for Isolation of Rigid Partition Walls Figure D-3 Typical Seismic Restraints for Floor-mounted Equipment Figure D-4 Typical Seismic Restraints for Suspended Equipment Figure D-5 Acceptable Seismic Details for Pipe Sway Bracing Figure D-6 Pinned-pinned Support Condition for Table D-1 Figure D-7 Fixed-pinned Support Condition for Table D-2 Figure D-8 Fixed-fixed Support Condition for Table D-3 Figure D-9 Period Coefficients for Uniform Beams Figure D-10 Single Guyed Stacks Figure D-11 Elevator Details xi

TABLES

Table 2-1 Lateral Deflection Limits for Framing Supporting Exterior Wall Finishes

Table 2-2 Risk Category of Buildings and Other Structures Table 2-3 Maximum Allowable Wall Load at a Thickened Slab for Wall Load

Near Center of Slab or Near Keyed or Doweled joints Table 2-4 Maximum Allowable Wall Load at a Thickened Slab for Wall Load

Near Free Edge Table 3-1 Replacement for ASCE 7-16 Table 12.2-1 Design Coefficients and

Factors for Basic Seismic Force-Resisting Systems Table 4-1 Replacement for ASCE 41-13 Table 4-6, Benchmark Buildings Table 6-1 Minimum Thickness of Masonry Walls Table 7-1 Replacement for ASCE 7-16 Table 12.2-1 Design Coefficients and

Factors for Basic Seismic Force-Resisting Systems Table C-1 System Limitations for Risk Category IV Buildings Designed Using

Alternate Procedure of Chapter 3 Table D-1 Maximum Span for Rigid Pipe with Pinned-Pinned Conditions, L .. 139 Table D-2 Maximum Span for Rigid Pipe with Fixed-Pinned Condition, L Table D-3 Maximum Span for Rigid Pipe with Fixed-Fixed Condition, L Table G-1 Minimum Uniformly Distributed Live Loads and Minimum

Concentrated Live Loadsg xii

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INTRODUCTION

PURPOSE AND SCOPE.

This Unified Facility Criteria (UFC) provides requirements for structures designed and constructed for the Department of Defense (DoD). These technical requirements are based on the 2018 International Building Code (2018 IBC), as modified by UFC 1-200- 01, DoD Building Code (General Building Requirements), and the structural standard referenced by the 2018 IBC: ASCE/SEI 7-16 Minimum Design Loads and Associated Criteria for Buildings and Other Structures (hereinafter referred to simply as ASCE 7-16).

The criteria further provides limited technical guidance for seismic evaluation and strengthening of existing buildings, and references the 2018 edition of the International Existing Building Code (2018 IEBC), ICSSC RP 8 / NIST GCR 11-917-12, Standards of Seismic Safety for Existing Federally Owned and Leased Buildings (RP 8) as well as ASCE/SEI 41-17, Seismic Evaluation and Retrofit of Existing Buildings (hereinafter re-ferred to simply as ASCE 41-13). This information is for use by structural engineers to develop design calculations, specifications, plans, and design-build Requests for Pro-posal (RFPs), and it is meant to serve as the minimum design requirement for DoD buildings.

BACKGROUND.

UFC 1-200-01 implements and supplements 2018 IBC as the building code for DoD.

Chapter 2 of this UFC further modifies the IBC for structural-specific design require-ments and is organized by the chapter of the IBC that each section modifies. Apply any section in the 2018 IBC, that is not specifically referenced, as it is written in the 2018 IBC. Chapter 3 of this UFC further modifies ASCE 7-16 for structural-specific design re-quirements and is organized by the chapter of ASCE 7 that each section modifies. Ap-ply any section in ASCE 7-16, that is referenced by the 2018 IBC but is not modified in Chapter 3 of this UFC, as it is written in ASCE 7-16.

The 2018 IBC and ASCE 7-16 section modifications are one of four actions, according to the following legend:

[Addition] – Add new section, including new section number, not shown in 2018 IBC or ASCE 7-16.

[Deletion] – Delete referenced 2018 IBC or ASCE 7-16 section or noted portion of a section.

[Replacement] – Delete referenced 2018 IBC or ASCE 7-16 section or noted portion and replace it with the narrative shown.

[Supplement] – Add narrative shown as a supplement to the narrative shown in the referenced section of 2018 IBC or ASCE 7-16.

The climatic and seismic data referenced in this UFC are intended as tools to assist in the consistent interpretation of the corresponding data in the IBC at significant DoD in-stallations within the United States, and as the basis for applying the provisions of UFC 1-200-01 to significant DoD installations outside of the United States.

APPLICABILITY.

This UFC applies to all service elements and contractors involved in the planning, de-sign and construction of DoD facilities worldwide.

CONFLICTS AND MODIFICATIONS.

The 2018 IBC provisions are directed toward public health, safety, and general welfare, presenting minimum standards that must be met by the private sector construction in-dustry. The use of industry standards for DoD projects promotes communication in the marketplace, improves competition, and results in cost savings. However, the military sometimes requires higher standards to achieve unique building performance, or to con-struct types of facilities that are not used in the private sector. In addition, the construc-tion of military facilities outside the United States can introduce requirements that are not addressed in national model building codes. Modifications to the 2018 IBC and ASCE 7-16 provisions contained herein are intended to fulfill those unique military re-quirements. Where conflicts between the 2018 IBC or ASCE 7-16 and this UFC arise, this UFC prevails.

In addition, for construction outside the United States, conflicts between host nation building codes and the UFC may arise. In those instances, the more stringent design provisions prevail.

OVERVIEW OF THIS UFC.

Brief descriptions of the various chapters and appendices of this UFC follow.

Chapter 2 – MODIFICATIONS TO IBC. Chapter 2 provides supplemental re-quirements for applying the 2018 IBC structural provisions to conventional DoD building design by listing required modifications for specific 2018 IBC sections.

The 2018 IBC sections that are not referenced in Chapter 2 or otherwise modi-fied by provisions of Appendix C apply as they are written in the 2018 IBC.

Chapter 3 – MODIFICATIONS TO ASCE 7. Chapter 3 provides supplemental re-quirements for applying the ASCE 7-16 structural provisions to conventional DoD building design by listing required modifications for specific ASCE 7-16 sections.

The ASCE 7-16 sections that are adopted by the 2018 IBC but are not refer-enced in Chapter 3 or otherwise modified by provisions of Appendix C apply as they are written in ASCE 7-16.

CHAPTER 4 - SEISMIC EVALUATION AND RETROFIT OF EXISTING BUILD-

INGS. This chapter contains provisions for the repair, alteration, change of occu-pancy, acquisition, addition to and relocation of existing buildings. For this pur-pose, this chapter adopts by reference the provisions of ICSSC RP 8 / NIST

GCR 11-917-12, Standards of Seismic Safety for Existing Federally Owned and Leased Buildings, cited herein as RP 8 as well as those of ASCE/SEI 41-13, Seismic Evaluation and Retrofit of Existing Buildings. Where RP 8 makes no spe-cific provision, this chapter adopts the provisions of the 2018 IEBC Prescriptive Compliance Method. This chapter also makes revisions to specific sections in RP 8 and the 2018 IEBC.

CHAPTER 5 – NONBUILDING STRUCTURES. This chapter lists the names of various standards and other guidelines to be followed for the design of highway bridges, railroad bridges, tanks for liquid storage, tanks for petroleum storage, environmental engineering concrete structures, prestressed concrete tanks, wa-ter treatment facility structures, transmission towers and poles, antenna towers, and pedestrian bridges.

CHAPTER 6 – MODIFICATIONS TO THE IBC FOR CRITICAL HEALTHCARE

FACILITIES. This chapter contains a number of additional requirements for cer-tain critical healthcare facilities identified in the chapter. The requirements are presented in the form of modifications to Chapters 16, 18, 19, 20, 21, and 22 of the IBC.

CHAPTER 7 – MODIFICATIONS TO ASCE 7 FOR CRITICAL HEALTHCARE

FACILITIES. This chapter contains a number of additional requirements for the same healthcare facilities within the scope of Chapter 6. The requirements are presented in the form of modifications to Chapters 11, 12, and 13 of ASCE 7.

Appendix A – REFERENCES. The UFC has an extensive list of referenced pub-lic documents. The primary references for this UFC are the 2018 IBC and ASCE 7-16.

Appendix B – BEST PRACTICES. This chapter provides useful recommenda-tions and guidance on a number of important topics such as building drift limits, impact resistant glazing, wind and seismic loads on photovoltaic arrays, etc.

Appendix C – ALTERNATE DESIGN PROCEDURE FOR BUILDINGS AND OTHER STRUCTURES IN RISK CATEGORY IV. For buildings assigned to Risk Category IV, those that are “essential” because of their military function or post-earthquake recovery role, the 2018 IBC /ASCE 7-16 requires higher design lateral loads and more stringent structural detailing procedures than those for buildings assigned to Risk Category I, II, or III. Applying nonlinear analysis pro-cedures may result in more economical or better-performing Risk Category IV buildings than linear elastic procedures can provide. While the 2018 IBC/ASCE 7-16 permits nonlinear static analysis procedures, it provides little guidance on how to perform them. Appendix C presents optional nonlinear static analysis procedures that may be used for Risk Category IV buildings. Apply the optional nonlinear procedures outlined in Appendix C only with the approval of the Con-tracting Officer.

Appendix D – GUIDANCE FOR SEISMIC DESIGN OF NONSTRUCTURAL COMPONENTS. Appendix D provides guidance for seismic design of nonstruc-tural components. Requirements for design of nonstructural components in this UFC are supplemented by guidance provided in this appendix.

Appendix E – MECHANICAL AND ELECTRICAL COMPONENT CERTIFICA- TION. Appendix E provides guidance in addition to what is available in ASCE 7- 16 Section 13.2.2 on certification of mechanical and electrical components.

Appendix F – ABBREVIATIONS. This appendix lists all the abbreviated terms used in this UFC.

Appendix G – MINIMUM UNIFORMLY DISTRIBUTED LIVE LOADS, LO, AND MINIMUM CONCENTRATED LIVE LOADS. This appendix contains Table G-1, which replaces Table 1607.1 of the 2018 IBC, and includes additional occupancy or use classification for military facilities that are shown in bold italics

COMMENTARY.

Limited commentary has been provided in the chapters. Section designations for such commentary are preceded by a “[C]”, and the commentary narrative is shaded.

OTHER CRITERIA.

Military criteria other than those listed in this document may be applicable to specific types of structures. Such structures must meet the additional requirements of the appli-cable military criteria.

Comply with UFC 1-200-01, DoD Building Code (General Building Requirements). UFC 1-200-01 provides applicability of model building codes and government unique criteria for typical design disciplines and building systems, as well as for accessibility, antiterror-ism, security, high performance and sustainability requirements, and safety. Use this UFC in addition to UFC 1-200-01 and the UFCs and government criteria referenced therein.

Apply UFC 4-023-03, Design of Buildings to Resist Progressive Collapse, if required by UFC 4-010-01, DoD Minimum Antiterrorism Standards for Buildings. UFC 3-301-01 and UFC 4-023-03 both apply in that case. Design in accordance with one does not guaran-tee compliance with the other.

An additional risk category not included in the 2018 IBC/ASCE 7-16, Risk Category V, has been added to address national strategic military assets. Structures in this risk cat-egory are designed to remain elastic during the MCER. Refer to UFC 3-301-02 for the design of all RC V structures.

MODIFICATIONS TO IBC

IBC CHAPTER 1 - SCOPE AND ADMINISTRATION.

101.4.7 – Existing Buildings [Supplement]

For seismic evaluation and retrofit of existing buildings, the provisions of Chapter 4 of this UFC apply to all matters governing the repair, alteration, change of oc-cupancy, acquisition, addition and relocation. Where the provisions of Chapter 4 and the 2018 IEBC are in conflict, those of Chapter 4 govern. Section 116 - UN-

SAFE STRUCTURES AND EQUIPMENT.

[C] 101.4.7 – Existing Buildings [Supplement]

The purpose of this [Supplement] must direct users to specific provisions for seismic evaluation and retrofit of existing buildings. In the 2012 IBC, the exist-ing building provisions were in Chapter 34. In the 2015 and 2018 editions of the IBC, Chapter 34 consists solely of the following statement: “Action taken during the 2012 Code Development Process removed Chapter 34, Existing Struc-tures, from the IBC. The provisions of this chapter are contained in the Interna-tional Existing Building Code. See Section 101.4.7.” The 2018 IEBC contains three alternative compliance methods; the Prescriptive Compliance Method fol-lows the same layout and philosophy as the previous IBC Chapter 34. Chapter 4 of this UFC cites a federal recommended practice document (ICSSC RP 8) and a national standard (ASCE 41-13) for seismic evaluation and retrofit of ex-isting buildings. The chapter provides some modifications and clarifications to the requirements of RP 8 and ASCE 41-13.

116.5 – Restoration [Replacement]

Where the structure or equipment determined to be unsafe by the AHJ is re-stored to a safe condition, to the extent that repairs, alterations or additions are made or a change of occupancy occurs during the restoration of the structure, such repairs, alterations, additions or change of occupancy must comply with the requirements of Sections 101.4.7, 105.2.2 and Chapter 4 of this UFC, as applica-ble.

IBC CHAPTER 2 – DEFINITIONS.

STRUCTURAL ENGINEER OF RECORD (SER) [Addition]

The Structural Engineer of Record (SER) is a registered design professional who performs or supervises the analysis, design, and document preparation for the building structural system. The SER is responsible for the design of the primary structural system, which is the completed combination of elements, which serve to support the building's self-weight, applicable live loads and environmental loads such as wind, seismic, and thermal.

IBC CHAPTER 4 – SPECIAL DETAILED REQUIREMENTS BASED ON OCCU-

PANCY AND USE.

423.3 – Critical Emergency Operations [Replacement]

In hurricane-prone regions (see ASCE 7 Section 26.2) and/or in areas where shelter design wind speeds for tornados equal or exceed 250 mph (see Figure 304.2(1) of ICC 500), the following facilities must comply with Table 1604.5 as Risk Category IV structures and must be provided with a storm shelter con-structed in accordance with ICC 500:

• 911 call stations

• Emergency operation centers

• Fire and ambulance stations

• Police stations

• Critical national defense functions that must be manned continuously and for which there is no redundant capability at a different location.

IBC CHAPTER 16 - STRUCTURAL DESIGN.

1603.1.5 – Earthquake Design Data Item 3 [Replacement]

3. Mapped spectral response acceleration parameters, Ss and S1, must be indi-cated. If the data are based on site-specific response analysis, this must be noted. Site-specific source data must also include whether response spectrum or time-history analyses were performed.

1603.1.10 – Systems/Components Requiring Special Inspection for Seismic Resistance [Addition]

Construction documents and specifications must be prepared for those systems and components requiring special inspection for seismic resistance, as specified in 2018 IBC Section 1705.12 as modified by appropriate special inspection sec-tion in UFC 1-200-01 and by the SER. Reference to seismic standards in lieu of detailed drawings is acceptable.

1603.2 - Delegated Engineered Systems [Addition]

The SER for a structure may delegate responsibility for the design of systems or component parts of the structure to a qualified delegated registered professional engineer. Both the SER for the structure and the delegated engineer must com-ply with the requirements of this UFC.

Exception: The SER must design and detail all primary lateral force resisting sys-tem connections for wind and seismic forces, including steel connections.

The following are some examples of optional delegated designs:

a. Prefabricated wood components

b. Cast-in-place post-tensioned concrete structural systems

c. Precast, prestressed concrete components

d. Open web steel joists and joist girders

e. Specialty foundation systems

f. Simple (shear only) steel connections (lateral must be designed by SER).

g. Cold-formed steel joist/stud/truss framing and pre-fabricated components

h. Seismic design and anchorage of nonstructural components

i. Proprietary track for under-hung cranes and monorails

j. Autoclaved aerated concrete

k. Cross-laminated timber connections

The delegated engineer must sign and seal all work they design. The SER must review all submittals that have been signed and sealed by the delegated engi-neer, to verify compliance with the design intent and the specified design criteria and to ensure coordination with the contract documents and other shop draw-ings. All submittals from the delegated engineer must be approved by the SER prior to the start of fabrication of the system or component part and prior to any field construction that may be affected by the system or component part.

1604.3 - Serviceability [Supplement]

The SER must ensure that the maximum allowable frame drift is suitable for the proposed structure considering occupancy, use/function, and all details of con-struction. See ASCE 7-16 Appendix C “Serviceability Considerations” including commentary, and Section B-1.1 of UFC 3-301-01 for additional guidance.

In the wind design of a building or non-building structure, lateral drift must not ex-ceed H/480 based on a wind speed with a 10 year MRI. See Figure CC.2-1 of ASCE 7 for wind speeds with a 10 year MRI. Consideration must be given to cladding systems when evaluating lateral drift as a more stringent drift limitation may be appropriate for certain cladding system.

1604.3.1 - Deflections [Replacement]

Deflections of structural members must not exceed the most restrictive of the lim-itations of Sections 1604.3.2 through 1604.3.5 or those permitted by Table 1604.3, or Table 2-1 of UFC 3-301-01.

Wind Induced Deflection Limits for Framing Supporting Exte-rior Wall Finishes a,b

Brick veneer L/600 Exterior Insulation Finish Systems L/240 Cement board L/360 Stone Masonry VERIFY WITH

STONE SUPPLIER

Plywood and Wood-Based Structural-Use Panels

L/240

Gypsum sheathing L/240 Metal or vinyl siding and insulated metal panel

L/240

Notes to Table 2-1, “Lateral Deflection Limits for Framing Supporting Exte-rior Wall Finishes”

a. The wind load is permitted to be taken as 0.42 times the “com-ponent and cladding” loads for the purpose of determining the deflection limits herein.

b. L must be calculated as L = k*l, where k is the theoretical ef-fective length factor, and l is the actual member length.

Table 1604.5 [Replacement]

Replace Table 1604.5 of the IBC with Table 2-2 of this UFC. All references in the IBC to Table 1604.5 must be interpreted as a reference to Table 2-2 of this UFC. Items that are different from those in 2018 IBC Table 1604.5 are shown in italics.

1604.11 - Fall Prevention and Protection [Addition]

To protect personnel during occupancy and maintenance phases, consider fall hazards at the planning and design phase of a project and eliminate them to the maximum extent possible. Also consider safe access to work location at heights.

Fall prevention and protection measures are prescribed in:

• 29 CFR 1910, Subpart D

• ANSI/ASSE A1264.1

• ANSI/ASSE Z359.6

When elimination or prevention of fall hazards is not feasible, include in design certified and labeled anchorages that are conveniently located to perform the work safely. The anchorages and the structural elements that support these an-chorages must meet the requirements of 2018 IBC Section 1607.10.4, as modi-fied by this UFC

Where fall protection is required near weight-handling equipment, prevent con-flicts between the weight-handling equipment and fall protection measures.

Risk Category of Buildings and Other Structures

Risk Category Nature of Occupancy

Seismic Factor

IE

Snow Factor

IS

Ice Factor

Ii

I

Buildings and other structures that repre-sent a low hazard to human life in the event of failure, including, but not limited to:

• Agricultural facilities

• Certain temporary facilities

• Minor storage facilities

1.00 0.8 0.80

II Buildings and other structures except those listed in Risk Categories I, III, IV and V 1.00 1.00 1.00

III

Buildings and other structures that represent a sub-stantial hazard to human life or represent signifi-cant economic loss in the event of failure, includ-ing, but not limited to:

• Buildings and other structures whose primary occu-pancy is public assembly with an occupant load greater than 300 people

• Buildings and other structures containing elementary school, secondary school, or daycare facilities with an occupant load greater than 250

• Buildings and other structures containing adult educa-tion facilities, such as colleges and universities, with an occupant load greater than 500

• Group I-2, Condition 1 occupancies with 50 or more care recipients

• Group I-2, Condition 2 occupancies not having emer-gency surgery or emergency treatment facilities

• Group I-3 occupancies

• Any other occupancy with an occupant load greater than 5,000a

• Power-generating stations; water treatment facilities for potable water, waste water treatment facilities, and other public utility facilities that are not included in Risk Categories IV and V

• Buildings and other structures not included in Risk Categories IV and V containing quantities of toxic, flam-mable, or explosive materials that:

Exceed maximum allowable quantities per control area as given in Table 307.1(1) or 307.1(2) or per outdoor control area in accordance with NFPA 1:

Fire Code; and are sufficient to pose a threat to the public if released.b

• Facilities having high-value equipment (including air-craft maintenance hangers), as designated by the AHJ

1.25 1.10 1.25

IV

Buildings and other structures designed as essen-tial facilities, including, but not limited to:

• Group I-2, Condition 2 occupancies having emer-gency surgery or emergency treatment facilities

• Ambulatory care facilities having emergency surgery or emergency treatment facilities

1.50 1.20 1.25

Risk Category Nature of Occupancy

Seismic Factor

IE

Snow Factor

IS

Ice Factor

Ii

• Fire, rescue, and police stations, and emergency vehi-cle garages

• Designated earthquake, hurricane, or other emer-gency shelters

• Designated emergency preparedness, communica-tion, and operation centers, and other facilities required for emergency response

• Power-generating stations and other utility facilities re-quired as emergency backup facilities for Risk Category IV structures.

• Buildings and other structures containing quantities of highly toxic materials that:

Exceed maximum allowable quantities per control area as given in Table 307.1(2) or per outdoor con-trol area in accordance with NFPA 1, Fire Code; and are sufficient to pose a threat to the public if re-leased.b

• Air traffic control tower (ATCT), Radar Approach Con-trol Facility (RACF) and air traffic control centers unless the AHJ determines that the facility is classified as a non-essential facility and is not required for post-earth-quake operations (i.e. minor facility, where an alternate temporary control facility is available, auxiliary outlying field, etc.). Contact the AHJ for additional guidance.

• Emergency aircraft hangars that house aircraft re-quired for post-earthquake emergency response; if no suitable back up facilities exist

• Buildings and other structures not included in Risk Category V, having DoD mission-essential command, control, primary communications, data handling, and in-telligence functions that are not duplicated at geograph-ically separate locations, as designated by the using agency

• Water storage facilities and pump stations required to maintain water pressure for fire suppression

V c

Facilities designed as national strategic military as-sets, including, but not limited to:

• Key national defense assets (e.g. National Missile De-fense facilities) without geographically separated redun-dant capability, as approved by the AHJ

• Facilities involved in operational missile control, launch, tracking, or other critical defense capabilities

• Emergency backup power-generating facilities re-quired for primary power for Category V occupancy

• Power-generating stations and other utility facilities re-quired for primary power for Category V occupancy, if emergency backup power generating facilities are not available

Facilities involved in storage, handling, or processing of nuclear, chemical, biological, or radiological materials,

1.0 1.50 1.50

Risk Category Nature of Occupancy

Seismic Factor

IE

Snow Factor

IS

Ice Factor

Ii where structural failure could have widespread cata-strophic consequences, as designated by the AHJ.

Notes to Table 2-2, “Risk Category of Buildings and Other Structures”

a. For purposes of occupant load calculations, occupancies required by Ta-ble 1004.5 to use gross floor area are permitted to use net floor area to determine the total occupant load.

b. Where approved by the AHJ, the classification of buildings and other structures as Risk Category III or IV based on their quantities of toxic, highly toxic or explosive materials is permitted to be reduced to Risk Cat-egory II, provided it can be demonstrated by hazard assessment in ac-cordance with Section 1.5.3 of ASCE 7 that a release of the toxic, highly toxic or explosive material is not sufficient to pose a threat to the public.

c. Risk Category V has been added to address national strategic military as-sets. Structures in this risk category are designed to remain elastic dur-ing the MCER. Refer to UFC 3-301-02 for the design of all RC V struc-tures.

1604.12 - Expansion Joints [Addition]

Follow the recommendations in NAS Technical Report No. 65 for spacing of ex-pansion joints .

1605.1.2 – Structural Members Sensitive to Vertical Ground Motion [Addi-tion]

Where the design earthquake spectral response acceleration parameter at short periods, SDS, is greater than 1.0g, the components from building and nonbuilding structures listed below must be designed for additional load combinations given in Sections 1605.2.2, Section 1605.3.1.3 and 1605.3.2.2 for Strength Design, Al-lowable Stress Design (basic load combinations) and Allowable Stress Design (alternative basic load combinations), respectively.

Building Structures:

• horizontal or nearly horizontal structural members spanning 65 ft or more

• horizontal or nearly horizontal cantilever components longer than 16 ft

• horizontal or nearly horizontal prestressed components

• building components, excluding foundations, in which demands due to gravity loads exceed 80% of the nominal strength of the component

• horizontal structural elements supporting discontinuous vertical elements of the gravity force-resisting system

• base-isolated structures

Nonbuilding Structures:

• long-span roof structures (e.g. stadiums or high bay aircraft maintenance hangars)

• electric power generation facilities

Exception: Nonbuilding structures addressed by ASCE 7-16 Section 15.1.4 are not required to comply with this section.

[C] 1605.1.2 Structural Members Sensitive to Vertical Ground Motion [Addition]

The effects of vertical earthquake ground motion on buildings have traditionally been given much less attention than the effects of horizontal ground motion. This is largely due to the belief that the peak vertical ground acceleration is considerably smaller than the peak horizontal ground acceleration. A fairly large safety factor against static vertical loads also exists in engineered buildings. As a result, it is generally consid-ered adequate to include the effects of vertical ground motions in the simplified form of 0.2SDSD, as done in the IBC and the ASCE 7-16 standard for many years. How-ever, certain structural members are particularly vulnerable to vertical ground mo-tions, and require more explicit consideration of such ground motions in their design.

This [Addition] addresses those specific members by incorporating additional provi-sions for design considering vertical ground motions.

The threshold value of SDS > 1.0g was derived from a similar requirement in the 2004 edition of Eurocode 8, which specified the peak vertical ground acceleration, avg, to be greater than 0.25g for its special provisions related to vertical ground motions to ap-ply. The derivation is as shown below:

1. From the vertical ground motion response spectrum given in ASCE 7-16 Section

11.9.2, the ratio of the peak vertical acceleration (spectral acceleration at T = 0) and the maximum vertical spectral acceleration (flat top portion of the response spectrum) is 0.3/0.8 = 0.375.

2. The maximum vertical spectral acceleration has been traditionally assumed to be

2/3SDS.

3. So, the peak vertical ground acceleration can be expressed in terms of SDS as:

avg = 0.375×(2/3SDS) = 0.25SDS

4. So, avg > 0.25g => SDS > 1.0g

1605.2.2 – Additional Load Combinations for Vertical Ground Motions [Ad-dition]

The following additional load combinations with seismic load effects must be con-sidered for elements of buildings and nonbuilding structures specified in Section 1605.1.2.

Where the prescribed seismic load effect, E = f(Ev, Eh), defined in ASCE 7-16 Section 12.4.2 or 12.14.3.1, is combined with the effects of other loads, the fol-lowing seismic load combinations apply:

1.2(D + F) + 1.0Ev0 + 0.3Eh + f1L + 1.6H + f2S (Equation 16-5A)

0.9(D + F) − Ev0 + 0.3Eh + 1.6H (Equation 16-7A)

Where the seismic load effect with overstrength, Em = f(Ev, Emh), defined in ASCE 7-16 Section 12.4.3, is combined with the effects of other loads, the following seismic load combinations apply:

1.2(D + F) + 1.0Ev0 + 0.3Emh + f1L + 1.6H + f2S (Equation 16-5A)

0.9(D + F) − Ev0 + 0.3Emh + 1.6H (Equation 16-7A)

The effect of vertical ground motion, Ev0, can be determined from one of the fol-lowing:

• Ev0 = 0.67SDSD

• Ev0 is determined by direct analysis using the design vertical response spec-trum given in ASCE 7-16 Section 11.9.

[C] 1605.2.2 – Additional Load Combinations for Vertical Ground Mo-tions [Addition]

The additional load combinations were derived using the 100+30 rule of com-bining the effects from orthogonal seismic loads. The code-specified vertical ground motion effect (0.2SDSD) can be derived by first assuming peak vertical ground motion component to be 2/3rd of the corresponding peak horizontal component, and then combining 30% of that (0.3×0.67SDS = 0.2SDS) with 100% of the horizontal seismic load effects. This section simply adds two more load combinations where 100% of the vertical seismic load effect is combined with 30% of the horizontal seismic load effect.

1605.3.1.3 – Additional Load Combinations for Vertical Ground Motions [Addition]

The following additional load combinations with seismic load effects must be con-sidered for elements of buildings and nonbuilding structures specified in Section 1605.1.2.

Where the prescribed seismic load effect, E = f(Ev, Eh), defined in ASCE 7-16 Section 12.4.2 or 12.14.3.1, is combined with the effects of other loads, the fol-lowing seismic load combinations apply:

D + H + F + 0.7Ev0 + 0.21Eh (Equation 16-12A)

D + H + F + 0.75 (0.7Ev0 + 0.21Eh) + 0.75L + 0.75S (Equation 16-14A)

0.6(D + F) – 0.7Ev0 + 0.21Eh + H (Equation 16-16A)

Where the seismic load effect with overstrength, Em = f(Ev, Emh), defined in ASCE 7-16 Section 12.4.3, is combined with the effects of other loads, the following seismic load combinations apply:

D + H + F + 0.7Ev0 + 0.21Emh (Equation 16-12A)

D + H + F + 0.75 (0.7Ev0 + 0.21Emh) + 0.75L + 0.75S (Equation 16-14A)

0.6(D + F) – 0.7Ev0 + 0.21Emh + H (Equation 16-16A)

The effect of vertical ground motion, Ev0, can be determined from one of the fol-lowing:

• Ev0 = 0.67SDSD

• Ev0 is determined by direct analysis using the design vertical response spec-trum given in ASCE 7-16 Section 11.9.

[C] 1605.3.1.3 – Additional Load Combinations for Vertical Ground Mo-tions [Addition]

See the commentary to Section 1605.2.2 above for some background on how the additional load combinations were derived.

1605.3.2.2 – Additional Load Combinations for Vertical Ground Motions

The following additional load combinations with seismic load effects must be con-sidered for elements of buildings and nonbuilding structures specified in Section 1605.1.2.

Where the prescribed seismic load effect, E = f(Ev, Eh), defined in ASCE 7-16 Section 12.4.2 or 12.14.3.1, is combined with the effects of other loads, the fol-lowing seismic load combinations apply:

D + L + S + Ev0/1.4 + Eh/4.6 (Equation 16-21A)

0.9D – Ev0/1.4 + Eh/4.6 (Equation 16-22A)

Where the seismic load effect with overstrength, Em = f(Ev, Emh), defined in ASCE 7-16 Section 12.4.3, is combined with the effects of other loads, the following seismic load combinations apply:

D + L + S + Ev0/1.4 + Emh/4.6 (Equation 16-21A)

0.9D – Ev0/1.4 + Emh/4.6 (Equation 16-22A)

The effect of vertical ground motion, Ev0, can be determined from one of the fol-lowing:

• Ev0 = 0.67SDSD

• Ev0 is determined by direct analysis using the design vertical response spec-trum given in ASCE 7-16 Section 11.9.

[C] 1605.3.2.2 – Additional Load Combinations for Vertical Ground Mo-tions [Addition]

See the commentary to Section 1605.2.2 above for some background on how the additional load combinations were derived.

1607.1 - General [Replacement]

Live loads are those loads defined in Section 1607.1. Table G-1 of this UFC de-fines minimum uniformly distributed live loads and minimum concentrated live loads for the design of structures. Table G-1 is IBC Table 1607.1 with additional Occupancy or Use classifications for military facilities. The classifications that have been added to IBC Table 1607.1 are shown in bold italics within Table G-1.

Table 1607.1 [Replacement]

Replace Table 1607.1 of the IBC with Table G-1 of this UFC. (All references in the IBC to Table 1607.1 must be interpreted as references to Table G-1 of this

UFC.)

1607.7.1 - Loads [Replacement]

Where a structure does not restrict access for vehicles that exceed a 10,000 pound (4536 kg) gross vehicle weight rating, those portions of said structure sub-ject to such loading must be designed using the vehicular live loads, including consideration of impact and fatigue, in accordance with the AASHTO Bridge De-sign Specification.

1607.10.4 – Fall arrest and lifeline anchorages [Supplement]

Fall arrest anchorages must be capable of supporting at least 5,000 pounds per person attached, or be designed, installed and used as part of a complete fall ar-rest system which maintains a safety factor of at least 2.0 under the supervision of a qualified person. See ANSI/ASSE Z359.6 for additional requirements and design guidance (Note: the 1.6 load factor used in Z359.6 for active forces must be replaced by 2.0).

1607.10.5 - Hangers [Addition]

The design live load on hanger bay walls supporting floors and balconies must be increased by 33 percent to account for impact.

1607.12 - Distribution of Floor Loads [Supplement]

Add the following to the end of the paragraph: “Partial floor live load must be distributed per Section 4.3.3 of ASCE 7”.

1608.4 - Specific Locations within the United States [Addition]

Ground snow loads at DoD installations within the United States and its territories and possessions are identified using the structural load data tool hosted on the Whole Building Design Guide website at https://www.wbdg.org/additional-resources/tools/ufcsldt

Exception: Ground snow load at locations in the State of Montana must be de-termined from http://snowload.montana.edu/.

1608.5 - Specific Locations Outside of the United States [Addition]

Ground snow loads at specific locations outside of the United States and its terri-tories and possessions are identified using the structural load data tool hosted on the Whole Building Design Guide website at https://www.wbdg.org/additional-resources/tools/ufcsldt

At locations where the ground snow load is not provided, use the best locally available information. For additional guidance, contact the AHJ.

1608.6 - Snow Load Case Studies [Addition]

Snow load case studies may be done to clarify and refine snow loadings at site-specific locations with the approval of the AHJ. Where required by the AHJ, a site-specific study must be conducted if the ground snow load is greater than 30 psf (1.4KPa). The methodology used to conduct snow load case studies at site-specific locations is presented in the Cold Regions Research and Engineering Laboratory (CRREL) report “Database and Methodology for Conducting Site Specific Snow Load Case Studies for the United States.”

1609.1.1 – Determination of Wind Loads [Supplement]

Add the following to the list of exceptions:

7. For winds parallel to the ridge of open buildings, the wind load delivered to the main wind force resisting system from the bare frames or partially clad end walls must be determined in accordance with the provisions of ASCE 7-16 Section 28.3.5.

1609.1.2 – Aircraft Hangar Wind Loads [Addition]

Wind load on main wind force resisting system of aircraft hangars must be deter-mined based on the following conditions:

• Hangar doors closed for winds at the maximum design velocity. Calculate the structural forces based upon the assumption of a “partially enclosed building.” It is permissible to use the large volume reduction factor of ASCE 7 in determining the design wind pressures. Assume that a 1-inch (25-mm) strip around the perimeter of all hangar door panels is an open-ing and combine this with the area of all unshielded fenestration.

• Hangar doors open to the maximum extent possible with a wind velocity of 60 mph (97 km/h). Calculate the structural forces upon the assumption of a “partially enclosed building.” Use the total open door area in the large volume reduction factor calculation.

1609.2.4 - Vertical Lift Fabric Hangar Doors (VLFD) [Addition]

Vertical Lift Fabric Doors are prohibited within windborne debris regions.

Navy/Marine Corps and Army provision: In addition to windborne debris regions, VLFD’s are prohibited for use in aircraft maintenance hangars where risk cate-gory III wind speeds equal or exceed wind speeds defining a windborne debris region. Namely, 130 mph (58 m/s) within one mile of the coastal mean high-wa-ter line or 140 mph (63.6 m/s) anywhere.

[C] 1609.2.4 – Vertical Lift Fabric Hangar Doors (VLFD) [Addition]

VLFD’s are currently prohibited for use in windborne debris regions due to past failures experienced during hurricane Michael. These failures were predomi-nately caused by wind driven debris. Additionally, the Navy, Marine Corps and Army have prohibited VLFD use where hangar design wind speeds are con-sistent with windborne debris regions, which provides commensurate design wind speed protection against windborne debris for Risk Category III hangar fa-cilities.

1609.2.5 – Roll Up Doors and Sectional Doors in Hurricane Prone Regions

In hurricane prone regions, warehouse and/or garage roll up doors or sectional doors must be pressure tested for components and cladding design wind pres-sure and shown to pass in accordance with ANSI/DASMA 108, Standard Method for Testing Sectional Garage Doors and Rolling Doors. This requirement must be noted on the construction drawings in addition to the project specifications.

The SER must specify the components and cladding design wind pressure for garage/sectional doors on the construction drawings.

1609.3.1 - Wind Speed Conversion [Replacement]

When required, the basic design wind speed can be converted to an allowable stress design wind speed, Vasd, using Equation 16-33a.

Vasd=√0.6V (Equation 16-33a)

When required, the basic design wind speed can be converted to a fastest-mile wind speed, Vfm, using Equation 16-33b.

Vfm=(√0.6V-10.5)/1.05 (Equation 16-33b)

1609.3.2 - Specific Locations Within the United States [Addition]

Basic design wind speeds at DoD installations within the United States and its territories and possessions can be identified using the structural load data tool hosted on the Whole Building Design Guide website at:

https://www.wbdg.org/additional-resources/tools/ufcsldt

1609.3.3 - Specific Locations Outside of the United States [Addition]

Basic design wind speeds at specific locations outside of the United States and its territories and possessions can be identified using the structural load data tool hosted on the Whole Building Design Guide website at:

At locations where the basic design wind speed is not provided, use the best lo-cally available information. For additional guidance, contact the AHJ.

1613.1 – Scope [Supplement]

For all structures, wherever ASCE 7-16 Table 12.2-1 is referenced, it must be re-placed by Table 3-1 of this UFC.

[C] 1613.1 – Scope [Supplement] Although Chapter 14 of ASCE 7-16 is not adopted by the 2018 IBC, occasional refer-ences to ASCE 7-16 Chapter 14 sections are made in this UFC.

1613.2.1.1 - Specific Locations within the United States [Addition]

Seismic parameters at DoD installations within the United States and its territo-ries and possessions are can be identified using the structural load data tool hosted on the Whole Building Design Guide website at

1613.2.1.2 - Specific Locations Outside of the United States [Addition]

Seismic ground motion parameters at specific locations outside of the United States and its territories and possessions can be identified using the structural load data tool hosted on the Whole Building Design Guide website at https://www.wbdg.org/additional-resources/tools/ufcsldt.

For locations not shown, the best available information must be used with the ap-proval of the AHJ. Appendix G includes available seismic spectral acceleration maps at selected locations outside of the United States. These maps may be used to interpolate the seismic ground motions at locations that are not identified in the above noted structural load data tool.

1613.2.1.3 – Site Specific Seismicity Study Process [Addition]

The site-specific ground motion procedures in Chapter 21 of ASCE 7 may be used to determine ground motions for any structure.

1613.3 – Ballasted Photovoltaic Panel Systems [Replacement]

Ballasted photovoltaic panel systems are not permitted.

[C] Ballasted Photovoltaic Panel Systems [Replacement] Ballasted systems are specifically disallowed by UFC 3-110-03, Roofing.

1613.4 - Procedure for Determining MCER and Design Spectral Response Accelerations [Addition]

Ground motion accelerations, represented by response spectra and coefficients derived from these spectra, must be determined in accordance with the proce-dure of ASCE 7-16 Sections 11.4.2-11.4.6, or the site-specific procedure of ASCE 7-16 Section 11.4.8. Subject to approval by the AHJ, a site-specific re-sponse analysis using the procedure of ASCE 7-16 Section 11.4.8 may be used in determining ground motions for any structure. Such analysis needs to include justification for its use in lieu of the mapped ground motion data that are de-scribed below.

A site-specific response analysis using the procedures of ASCE 7-16 Section

11.4.8 must be used for structures on sites classified as Site Class F (see ASCE 7-16 Section 20.3.1), unless the following condition is applicable:

The mapped Risk-Targeted Maximum Considered Earthquake (MCER) spectral response acceleration at short periods, Ss, and the mapped MCER spectral…