International Building Code Section 2106

International Building Code 2106.1

Seismic design requirements for masonry. Masonry
structures and components shall comply with the requirements
in Section 1.14.2.2 and Section 1.14.3, 1.14.4, 1.14.5, 1.14.6 or
1.14.7 of ACI 530/ASCE 5/TMS 402 depending on the structure’s
seismic design category as determined in Section 1613.
All masonrywalls, unless isolated on three edges from in-plane
motion of the basic structural systems, shall be considered to be
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part of the seismic-force-resisting system. In addition, the following
requirements shall be met.

Basic seismic-force-resisting system. Buildings
relying on masonry shear walls as part of the basic seismic-
force-resisting system shall comply with Section
1.14.2.2 of ACI 530/ASCE 5/TMS 402 or with Section
2106.1.1.1, 2106.1.1.2 or 2106.1.1.3.

Ordinary plain prestressed masonry shear
walls. Ordinary plain prestressed masonry shear walls
shall comply with the requirements of Chapter 4 of ACI
530/ASCE 5/TMS 402.

Intermediate prestressed masonry shear
walls. Intermediate prestressed masonry shear walls
shall comply with the requirements of Section 1.14.2.2.4
of ACI 530/ASCE 5/TMS 402 and shall be designed by
Chapter 4, Section 4.4.3, of ACI 530/ASCE 5/TMS 402
for flexural strength and by Section 3.3.4.1.2 of ACI
530/ASCE 5/TMS 402 for shear strength. Sections
1.14.2.2.5, 3.3.3.5 and 3.3.4.3.2(c) of ACI 530/ASCE
5/TMS 402 shall be applicable for reinforcement. Flexural
elements subjected to load reversals shall be symmetrically
reinforced. The nominal moment strength at
any section along a member shall not be less than
one-fourth the maximum moment strength. The
cross-sectional area of bonded tendons shall be considered
to contribute to the minimum reinforcement in Section
1.14.2.2.4 of ACI 530/ASCE 5/TMS 402. Tendons
shall be located in cells that are grouted the full height of
the wall.

Special prestressed masonry shear walls.
Special prestressed masonry shear walls shall comply
with the requirements of Section 1.14.2.2.5 of ACI
530/ASCE 5/TMS 402 and shall be designed by Chapter
4, Section 4.4.3, of ACI 530/ASCE 5/TMS 402 for flexural
strength and by Section 3.3.4.1.2 of ACI 530/ASCE
5/TMS 402 for shear strength. Sections 1.14.2.2.5(a),
3.3.3.5 and 3.3.4.3.2(c) of ACI 530/ASCE 5/TMS 402
shall be applicable for reinforcement. Flexural elements
subjected to load reversals shall be symmetrically reinforced.
The nominal moment strength at any section
along a member shall not be less than one-fourth the
maximum moment strength. The cross-sectional area of
bonded tendons shall be considered to contribute to the
minimum reinforcement in Section 1.14.2.2.5 of ACI
530/ASCE 5/TMS 402.

Prestressing tendons. Prestressing tendons
shall consist of bars conforming to ASTM A
722.

Grouting. All cells of the masonry wall
shall be grouted.

International Building Code 2106.1.1

Basic seismic-force-resisting system. Buildings
relying on masonry shear walls as part of the basic seismic-
force-resisting system shall comply with Section
1.14.2.2 of ACI 530/ASCE 5/TMS 402 or with Section
2106.1.1.1, 2106.1.1.2 or 2106.1.1.3.

Ordinary plain prestressed masonry shear
walls. Ordinary plain prestressed masonry shear walls
shall comply with the requirements of Chapter 4 of ACI
530/ASCE 5/TMS 402.

Intermediate prestressed masonry shear
walls. Intermediate prestressed masonry shear walls
shall comply with the requirements of Section 1.14.2.2.4
of ACI 530/ASCE 5/TMS 402 and shall be designed by
Chapter 4, Section 4.4.3, of ACI 530/ASCE 5/TMS 402
for flexural strength and by Section 3.3.4.1.2 of ACI
530/ASCE 5/TMS 402 for shear strength. Sections
1.14.2.2.5, 3.3.3.5 and 3.3.4.3.2(c) of ACI 530/ASCE
5/TMS 402 shall be applicable for reinforcement. Flexural
elements subjected to load reversals shall be symmetrically
reinforced. The nominal moment strength at
any section along a member shall not be less than
one-fourth the maximum moment strength. The
cross-sectional area of bonded tendons shall be considered
to contribute to the minimum reinforcement in Section
1.14.2.2.4 of ACI 530/ASCE 5/TMS 402. Tendons
shall be located in cells that are grouted the full height of
the wall.

Special prestressed masonry shear walls.
Special prestressed masonry shear walls shall comply
with the requirements of Section 1.14.2.2.5 of ACI
530/ASCE 5/TMS 402 and shall be designed by Chapter
4, Section 4.4.3, of ACI 530/ASCE 5/TMS 402 for flexural
strength and by Section 3.3.4.1.2 of ACI 530/ASCE
5/TMS 402 for shear strength. Sections 1.14.2.2.5(a),
3.3.3.5 and 3.3.4.3.2(c) of ACI 530/ASCE 5/TMS 402
shall be applicable for reinforcement. Flexural elements
subjected to load reversals shall be symmetrically reinforced.
The nominal moment strength at any section
along a member shall not be less than one-fourth the
maximum moment strength. The cross-sectional area of
bonded tendons shall be considered to contribute to the
minimum reinforcement in Section 1.14.2.2.5 of ACI
530/ASCE 5/TMS 402.

Prestressing tendons. Prestressing tendons
shall consist of bars conforming to ASTM A
722.

Grouting. All cells of the masonry wall
shall be grouted.

International Building Code 2106.1.1.1

Ordinary plain prestressed masonry shear
walls. Ordinary plain prestressed masonry shear walls
shall comply with the requirements of Chapter 4 of ACI
530/ASCE 5/TMS 402.

International Building Code 2106.1.1.2

Intermediate prestressed masonry shear
walls. Intermediate prestressed masonry shear walls
shall comply with the requirements of Section 1.14.2.2.4
of ACI 530/ASCE 5/TMS 402 and shall be designed by
Chapter 4, Section 4.4.3, of ACI 530/ASCE 5/TMS 402
for flexural strength and by Section 3.3.4.1.2 of ACI
530/ASCE 5/TMS 402 for shear strength. Sections
1.14.2.2.5, 3.3.3.5 and 3.3.4.3.2(c) of ACI 530/ASCE
5/TMS 402 shall be applicable for reinforcement. Flexural
elements subjected to load reversals shall be symmetrically
reinforced. The nominal moment strength at
any section along a member shall not be less than
one-fourth the maximum moment strength. The
cross-sectional area of bonded tendons shall be considered
to contribute to the minimum reinforcement in Section
1.14.2.2.4 of ACI 530/ASCE 5/TMS 402. Tendons
shall be located in cells that are grouted the full height of
the wall.

International Building Code 2106.1.1.3

Special prestressed masonry shear walls.
Special prestressed masonry shear walls shall comply
with the requirements of Section 1.14.2.2.5 of ACI
530/ASCE 5/TMS 402 and shall be designed by Chapter
4, Section 4.4.3, of ACI 530/ASCE 5/TMS 402 for flexural
strength and by Section 3.3.4.1.2 of ACI 530/ASCE
5/TMS 402 for shear strength. Sections 1.14.2.2.5(a),
3.3.3.5 and 3.3.4.3.2(c) of ACI 530/ASCE 5/TMS 402
shall be applicable for reinforcement. Flexural elements
subjected to load reversals shall be symmetrically reinforced.
The nominal moment strength at any section
along a member shall not be less than one-fourth the
maximum moment strength. The cross-sectional area of
bonded tendons shall be considered to contribute to the
minimum reinforcement in Section 1.14.2.2.5 of ACI
530/ASCE 5/TMS 402.

Prestressing tendons. Prestressing tendons
shall consist of bars conforming to ASTM A
722.

Grouting. All cells of the masonry wall
shall be grouted.

International Building Code 2106.1.1.3.1

Prestressing tendons. Prestressing tendons
shall consist of bars conforming to ASTM A
722.

International Building Code 2106.1.1.3.2

Grouting. All cells of the masonry wall
shall be grouted.

International Building Code 2106.2

Anchorage of masonry walls. Masonry walls shall be
anchored to the roof and floors that provide lateral support for
the wall in accordance with Section 1604.8.2.

International Building Code 2106.3

Seismic Design Category B. Structures assigned to
Seismic Design Category B shall conform to the requirements
of Section 1.14.4 of ACI 530/ASCE 5/TMS 402 and to the
additional requirements of this section.

Masonry walls not part of the lateral-
force-resisting system. Masonry partition walls,
masonry screen walls and other masonry elements that are
not designed to resist vertical or lateral loads, other than
those induced by their own mass, shall be isolated from the
structure so that the vertical and lateral forces are not
imparted to these elements. Isolation joints and connectors
between these elements and the structure shall be designed
to accommodate the design story drift.

International Building Code 2106.3.1

Masonry walls not part of the lateral-
force-resisting system. Masonry partition walls,
masonry screen walls and other masonry elements that are
not designed to resist vertical or lateral loads, other than
those induced by their own mass, shall be isolated from the
structure so that the vertical and lateral forces are not
imparted to these elements. Isolation joints and connectors
between these elements and the structure shall be designed
to accommodate the design story drift.

International Building Code 2106.4

Additional requirements for structures in Seismic
Design Category C. Structures assigned to Seismic Design
Category C shall conform to the requirements of Section
2106.3, Section 1.14.5 of ACI 530/ASCE 5/TMS 402 and the
additional requirements of this section.

Design of discontinuous members that are part
of the lateral-force-resisting system. Columns and pilasters
that are part of the lateral-force-resisting system and
that support reactions from discontinuous stiff members
such as walls shall be provided with transverse reinforcement
spaced at no more than one-fourth of the least nominal
dimension of the column or pilaster. The minimum transverse
reinforcement ratio shall be 0.0015. Beams supporting
reactions from discontinuous walls or frames shall be
provided with transverse reinforcement spaced at no more
than one-half of the nominal depth of the beam. The minimum
transverse reinforcement ratio shall be 0.0015.

International Building Code 2106.4.1

Design of discontinuous members that are part
of the lateral-force-resisting system. Columns and pilasters
that are part of the lateral-force-resisting system and
that support reactions from discontinuous stiff members
such as walls shall be provided with transverse reinforcement
spaced at no more than one-fourth of the least nominal
dimension of the column or pilaster. The minimum transverse
reinforcement ratio shall be 0.0015. Beams supporting
reactions from discontinuous walls or frames shall be
provided with transverse reinforcement spaced at no more
than one-half of the nominal depth of the beam. The minimum
transverse reinforcement ratio shall be 0.0015.

International Building Code 2106.5

Additional requirements for structures in Seismic
Design Category D. Structures assigned to Seismic Design
Category D shall conform to the requirements of Section
2106.4, Section 1.14.6 of ACI 530/ASCE 5/TMS 402 and the
additional requirements of this section.

Loads for shear walls designed by the working
stress design method. When calculating in-plane shear or
diagonal tension stresses by the working stress design
method, shear walls that resist seismic forces shall be
designed to resist 1.5 times the seismic forces required by
Chapter 16. The 1.5 multiplier need not be applied to the
overturning moment.

Shear wall shear strength. For a shear wall
whose nominal shear strength exceeds the shear corresponding
to development of its nominal flexural strength,
two shear regions exist.
For all cross sections within a region defined by the base
of the shear wall and a plane at a distance Lw above the base
of the shear wall, the nominal shear strength shall be determined
by Equation 21-1.
(Equation 21-1)
The required shear strength for this region shall be calculated
at a distance Lw /2 above the base of the shear wall, but
not to exceed one-half story height.
For the other region, the nominal shear strength of the
shear wall shall be determined from Section 2108.
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International Building Code 2106.5.1

Loads for shear walls designed by the working
stress design method. When calculating in-plane shear or
diagonal tension stresses by the working stress design
method, shear walls that resist seismic forces shall be
designed to resist 1.5 times the seismic forces required by
Chapter 16. The 1.5 multiplier need not be applied to the
overturning moment.

International Building Code 2106.5.2

Shear wall shear strength. For a shear wall
whose nominal shear strength exceeds the shear corresponding
to development of its nominal flexural strength,
two shear regions exist.
For all cross sections within a region defined by the base
of the shear wall and a plane at a distance Lw above the base
of the shear wall, the nominal shear strength shall be determined
by Equation 21-1.
(Equation 21-1)
The required shear strength for this region shall be calculated
at a distance Lw /2 above the base of the shear wall, but
not to exceed one-half story height.
For the other region, the nominal shear strength of the
shear wall shall be determined from Section 2108.
2006 INTERNATIONAL BUILDING CODE 399
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International Building Code 2106.6

Additional requirements for structures in Seismic
Design Category E or F. Structures assigned to Seismic
Design Category E or F shall conform to the requirements of
Section 2106.5 and Section 1.14.7 of ACI 530/ASCE 5/TMS
402.