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Page 1

EXPANSION JOINTS: WHERE, WHEN AND HOW


JAMES M. FISHER









James M. Fisher




Biography
James M. Fisher is vice president of Computerized Structural Design (CSD), a Milwaukee, Wisconsin, consulting
engineering firm. He received a Bachelor of Science degree in civil engineering from the University of Wisconsin
in 1962. After serving two years as a Lieutenant in the United States Army Corps of Engineers, he continued his
formal education. He received his Master of Science and Ph.D. degree in structural engineering from the University
of Illinois in 1965 and 1968 respectively. Prior to joining CSD, he was an assistant professor of structural
engineering at the University of Wisconsin at Milwaukee. He is a registered structural engineer in several states.
Fisher has specialized in structural steel research and development. He has spent a large part of his career
investigating building systems and the study of economical structural framing systems. He was a former chairman of
the American Society of Civil Engineers Committee on the Design of Steel Building Structures. Fisher is a member
of the American Iron and Steel Institute (AISI) Committee on Specifications, and a member of the AISC
Specification Committee for the Design Fabrication and Erection of Structural Steel Buildings. Fisher is the co-
author of seven books, as well as the author of many technical publications in the field of structural engineering.
He is a member of the American Society of Civil Engineers and honorary fraternities Tau Beta Pi, Sigma Xi, Chi
Epsilon and Phi Kappa Phi. Fisher received the 1984 T.R. Higgins Lectureship Award presented by the American
Institute of Steel Construction.

Abstract
This presentation will address means of determining where building expansion joints should be located within a
structure. When expansion joints are required, and how to proportion and design appropriate joints. Expansion
joints for commercial as well as industrial facilities will be discussed. Details of various types of joints will be
presented.

Page 2

EXPANSION JOINTS: WHERE WHEN AND HOW

JAMES M. FISHER1


Introduction
In the most basic sense the need for an expansion joint in a structure depends on the consequence of not having an
expansion joint. Will the lack of an expansion joint hamper or destroy the function of the facility, or cause damage
to the structural or architectural components? The number and location of building expansion joints is a design
issue not fully treated in technical literature. The LRFD Specification (AISC, 1999) lists expansion and contraction
as a serviceability issue and provides the statement in Section L2, “Adequate provision shall be made for expansion
and contraction appropriate to the service conditions of the structure.”

ASCE 7-02 “Minimum Design Loads for Buildings and Other Structures” (ASCE, 2002) states, “Dimensional
changes in a structure and its elements due to variations in temperature, relative humidity, or other effects shall not
impair the serviceability of the structure.”

This paper will focus on the basic requirements used to determine if an expansion joint is required at a given
location, or locations within a structure. Requirements of expansion joints as they pertain to commercial, industrial
and long span structures are discussed. Area dividers as provided in roof membranes to control the effects of
thermal loads for roofing are not discussed, as they are relief joints in the membrane and do not require a joint in the
roof structure below.


General Requirements
Although buildings are often constructed using flexible materials, roof and structural expansion joints are required
when plan dimensions are large. It is not possible to state exact requirements relative to distances between
expansion joints because of the many variables involved, such as, ambient temperatures during construction and the
expected temperature range during the life of a building. The National Roofing Contractors Association (NRCA,
2001) gives the following recommendations for the location of roof expansion joints:


Where steel framing, structural steel, or decking change direction.
Where separate wings of L, U, T shaped buildings or similar configurations exist.
Where the type of decking changes, for example, where a precast concrete deck and a steel deck abut.
Where additions are connected to existing buildings.
At junctions where interior heating conditions change, such as a heated office abutting unheated
warehouse, canopies, etc.
Where movement between walls and the roof deck may occur.


It should be noted that the NRCA standard details show that the roof structure under roof expansion joints is
intended to be discontinuous.

The Building Research Advisory Board of the National Academy of Sciences (NAS, 1974) published Federal
Construction Council Technical Report No. 65 “Expansion Joints in Buildings” (No longer in print). The report
presents the graph shown in Figure 1 as a guide for spacing expansion joints in beam and column frame buildings as
a function of design temperature change. The graph is directly applicable to buildings of beam and column
construction, hinged at the base, and with heated interiors. When other conditions prevail, the following rules are
applicable:


1. If the building will be heated only and will have hinged-column bases, use the allowable length as
specified;

2. If the building will be air conditioned as well as heated, increase the allowable length by 15 percent
(provided the environmental control system will run continuously);

3. If the building will be unheated, decrease the allowable length by 33 percent;

1 James M. Fisher is Vice President Computerized Structural Design, S.C., Milwaukee, WI

Page 7

Fig. 3 Shear Across Expansion Joint

BRACING SAG SUPPORT
CONNECT TO ONE SIDE
ONLY

Page 8

Fig. 4 Shear Across Expansion Joint



Example 1: 400 Foot Long Braced Frame

Determine whether a rectangular 400 ft. by 180 ft., unheated building with pinned base columns requires an
expansion joint. The building has x-bracing at one end only in the two side walls along the 400 ft. direction. The
building is located in Buffalo, New York.

From the Appendix: For Buffalo, New York: T

w
= 88, T

m
= 59, T

c
= 3


Design Temperature Change = Maximum of (T

w
-T

m)
or (T

m
-T

c
) = Maximum of (88-59) or (59-3) = 56 degrees


From Equation (1): ( )max 1 2 3 4L allow allowL R R R R L= + − − −

Where:
R

1
= 0.15, the building is not heated and nor air-conditioned, N.A.

R
2
= 0.33 the building is unheated.

R
3
= 0.25 the columns are fixed base, N.A.

R
4
= 0.25 the building has substantially greater stiffness at one end.


From Fig. 1: L

allow
= 450 ft.


( )( )maxL 450 0 0.33 0 0.25 450 189= + − − − = ft.

Page 13

Temperature ( F) Temperature ( F) Station
T

w
T

m
T

c


Station
T

w
T

m
T

c


St. Louis 98 65 4 Wilmington 93 63 23
Springfield 97 64 5 Winston/Salem 94 63 14

North Dakota Tennessee
Bismarck 95 60 -24 Bristol/Tri City 92 63 11
Devils Lake 93 58 -23 Chattanooga 97 60 15
Fargo 92 59 -22 Knoxville 95 60 13
Minot 91 ? -24 Memphis 98 62 17
Williston 94 59 -21 Nashville 97 62 12

Ohio Texas
Akron/Canton 89 60 1 Abilene 101 65 17
Cincinnati (CO) 94 62 8 Amarillo 98 66 8
Cleveland 91 61 2 Austin 101 68 25
Columbus 92 61 2 Brownsville 94 74 36
Dayton 92 61 0 Corpus Christi 95 71 32
Mansfield 91 61 1 Dallas 101 66 19
Sandusky (CO) 92 60 4 El Paso 100 65 21
Toledo 92 61 1 Fort Worth 102 66 20
Youngstown 89 59 1 Galveston 91 70 32
Houston 96 68 28
Oklahoma Laredo AFB 103 74 32
Oklahoma City 100 64 11 Lubbock 99 67 11
Tulsa 102 65 12 Midland 100 66 19
Port Arthur 94 69 29
Oregon San Angelo 101 65 20
Astoria 79 50 27 San Antonio 99 69 25
Eugene 91 52 22 Victoria 98 71 28
Medford 98 56 21 Waco 101 67 21
Pendleton 97 58 3 Wichita Falls 103 66 15
Portland 91 52 21
Roseburg 93 54 25 Utah
Salem 92 52 21 Salt Lake City 97 63 5

Pennsylvania Vermont
Allentown 92 61 3 Burlington 88 57 -12
Erie 88 59 7
Harrisburg 92 61 9 Virginia
Philadelphia 93 63 11 Lynchburg 94 62 15
Pittsburgh 90 63 5 Norfolk 94 60 20
Reading (CO) 92 61 6 Richmond 96 64 14
Scranton/Wilkes-Barre 89 61 2 Roanoke 94 63 15
Williamsport 91 61 1
Washington, D.C.
Rhode Island National Airport 94 63 16
Providence 89 60 6
Washington
South Carolina Olympia 85 51 21
Charleston 95 66 23 Seattle 85 51 20
Columbia 98 64 20 Spokane 93 58 -2
Florence 96 64 21 Walla Walla 98 57 12
Greenville 95 61 19 Yakima 94 62 6
Spartanburg 95 60 18
West Virginia

Page 14

Temperature ( F) Temperature ( F) Station

T
w
T

m
T

c


Station
T

w
T

m
T

c


South Dakota Charleston 92 63 9
Huron 97 62 -16 Huntington (CO) 95 63 10
Rapid City 96 61 -9 Parkersburg (CO) 93 62 8
Sioux Falls 95 62 -14

Wisconsin Wyoming
Green Bay 88 59 -12 Casper 92 59 -11
La Crosse 90 62 -12 Cheyenne 89 58 -6
Madison 92 61 -9 Lander 92 58 -16
Milwaukee 90 60 -6 Sheridan 95 59 -12

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