CEE 626 MASONRY DESIGN
SLIDES
Slide Set 3
Spring 2015
(Many slides modified from MSJC
Seminar Presentation)
1
Objectives

Introduce the Building code (BC) and
Masonry Design Standard and
Specification

Describe relationship between BC,
Design Standard and Load Standard.

Give an over view of the masonry
design Standard and how it is used –
assembly material properties

Apply standard to the design of
unreinforced masonry walls
Slide 2
Masonry Codes & Standards

Almost the entire US now uses the
IBC (Model Building Code), we will
focus on the 2015 IBC.

The IBC extensively references
“Consensus” Design and Material
Standards:




ASTM Standards for Materials
ASCE 7 for Loads
ACI 318 for Concrete
“MSJC” (TMS 402/602) for Masonry
Slide 3
IBC Masonry Requirements

In the past, some of the TMS 402/602
provisions were duplicated in the IBC.
Differences between the TMS 402/602
and the IBC were hard to spot. Same was
true of ASTM Standards.

Most of these duplicate provisions were
removed from the 2009 IBC, making
differences much easier to spot. More
duplicate provisions were deleted from the
2012 and additional duplications were
removed in the 2015 IBC
Slide 4
IBC Masonry Requirements –
Section 2107, ASD
For ASD, IBC Section 2107 requires compliance
with TMS 402 Chapter 8, except for:

Modifies splice & development lengths. Allows a
simpler procedure, and in some cases is more
conservative and in some cases less
conservative than the TMS 402

Has additional requirements for mechanical and
welded splices


ASTM A706 steel required for welded lap splices.

ACI 318 Type 1 or 2 mechanical splices required.
Limits the maximum bar size to No. 9.
Slide 5
The “MSJC” Code
and Specification...
Masonry Standards Joint Committee - MSJC
ACI
(ACI 530-13)
(ACI 530.1-13)
2013 “MSJC”
Code and
Specification
ASCE
(ASCE 5-13)
(ASCE 6-13)
Lead sponsor
TMS
(TMS 402-13)
(TMS 602-13)
Future editions
will be produced
solely by TMS. As
such, we’ll use
TMS 402/602
Slide 6
The “MSJC” Code and
Specification

MSJC began in 1978

MSJC develops Code and Specification under
ANSI consensus procedures, for reference by
model codes such IBC, NFPA

New edition of the Code and Specification
typically every 3 years





2011 edition is referenced by 2012 IBC
2008 edition is referenced by 2009 IBC
2005 edition is referenced by 2006 IBC
2002 edition is referenced by 2003 IBC
1999 edition is referenced by 2000 IBC
Slide 7
Back to TMS 402/602 - relation
between Code and Specification...

TMS 402 “Code”




Design provisions are given in Chapters 1 - 14 and
Appendices A, B and C
Sections 1.2.4 and Chapter 3 require a QA program in
accordance with the Specification
Section 1.4 invokes the Specification by reference.
TMS 602 “Specification”


verify compliance with specified f  m comply with required
level of quality assurance
comply with specified products and execution
Slide 8
2011 TMS 402 Code...
MSJC
TMS 602
Ch. 1 - General Requirements
Ch. 2
Allowable
Stress
Design
Ch. 3
Strength
Design
Ch. 4
Prestressed
Masonry
3.1 - General SD
3.2 - URM
3.3 - RM
2.1 - General ASD
2.2 - URM
2.3 - RM
Ch. 5
Empirical
Design
Ch. 6
Veneer
Ch. 7
Glass
Block
Ch. 8 AAC
6.1 - General
6.2 - Anchored
6.3 - Adhered
2011 TMS 402 also included a new
Appendix for Design of Masonry Infill
Slide 9
2013 TMS 402/602 Code
Reorganized...
Part 1: General
Part 2: Design
Requirements
Part 3:
Engineered
Design Methods
Part 4:
Prescriptive
Design Methods
Part 5:
Appendices &
References
Chapter 1 –
General
Requirements
Chapter 4: General
Analysis & Design
Considerations
Chapter 8: ASD
Chapter 12:
Veneer
Appendix A –
Empirical Design
of Masonry
Chapter 2 –
Notations &
Definitions
Chapter 5:
Structural
Elements
Chapter 9: SD
Chapter 13: Glass
Unit Masonry
Appendix B:
Design of Masonry
infill
Chapter 3 –
Quality &
Construction
Chapter 6:
Reinforcement,
Metal Accessories
& Anchor Bolts
Chapter 10:
Prestressed
Chapter 14:
Masonry Partition
Walls
Appendix C: Limit
Design of Masonry
Chapter 7: Seismic
Design
Requirements
Chapter 11: AAC
References
Slide 10
2013 TMS 402/602 - Reorganization

Part 1: General

Part 3: Engineered Design Methods
 Chapter 8: ASD
 Chapter 9: SD
 Chapter 10: Prestressed
 Chapter 11: AAC

Part 4: Prescriptive Design Methods
 Chapter 12: Veneer
 Chapter 13: Glass Unit Masonry
 Chapter 14: Masonry Partition Walls

Part 5: Appendices & References
 Appendix A – Empirical Design of
Masonry
 Appendix B: Design of Masonry infill
 Appendix C: Limit Design of Masonry
 References

Specification
Chapter 1 – General Requirements
 Chapter 2 – Notations & Definitions
 Chapter 3 – Quality & Construction


Part 2: Design Requirements

Chapter 4: General Analysis & Design
Considerations
 Chapter 5: Structural Elements
 Chapter 6: Reinforcement, Metal
Accessories & Anchor Bolts
 Chapter 7: Seismic Design
Requirements
User Friendly/Designer Input
5 Parts with smaller focused chapters
3 Appendices
Slide 11
TMS 602 Specification – Format
Consistent between editions
TMS 402 Code
TMS 602
Specification
Part 1
General
Part 2
Products
Part 3
Execution
1.6 Quality
assurance
2.1 - Mortar
2.2 - Grout
2.3 – Masonry Units
2.4 – Reinforcement
2.5 – Accessories
2.6 – Mixing
2.7 - Fabrication
3.1 - Inspection
3.2 - Preparation
3.3 – Masonry erection
3.4 – Reinforcement
3.5 – Grout placement
3.6 – Prestressing
3.7 – Field quality control
3.8 - Cleaning
Slide 12
Loads and Load Combinations

Vertical loads



gravity dead ( D ) and live ( L ) load
overturning forces from lateral Loads
Lateral loads




wind ( W )
earthquake ( E )
soil pressure ( H ) or fluid pressure ( F )
restrained movements due to temperature ,
shrinkage or creep ( T )
ASCE 7-10 ASD Load
Combinations Note
code references ASCE
7-10 or Bld. Code.
IBC 2012 & 2015 same
14
IBC Loads & Combinations
Design


Almost all reinforced masonry is designed by:

Allowable Stress Design per TMS 402 Parts 1 & 2 and
Chapter 8

Strength Design per TMS 402 Parts 1 & 2 and Chapter 9
Design is based on fm – Specified compressive
strength of masonry
Slide 16
Role of fm


fm – Specified compressive strength of masonry.
Synonymous to fc concrete
Concrete



designer states assumed value of fc
compliance is verified by compression tests on cylinders
cast in the field and cured under ideal conditions
Masonry


designer states assumed value of f’m
compliance is verified by “Unit Strength Method” or by
“Prism Test Method”
Slide 17
To verify compliance
with specified f’m

Unit strength method (Specification 1.4 B 2)




Estimates a conservative assemblage strength based
on mortar type and unit strength (from manufacturer)
Mortar must comply with ASTM C270
Grout must meet TMS 602 Specification Article 2.2 or
a compressive strength of 2000 psi
Prism test method (Specification 1.4 B 3)



Pro: can permit optimization of materials
Con: requires testing, qualified testing lab, and
procedures in case of non - complying results
Must comply with ASTM C1314
Slide 18
Unit Strength
Method Applicability
 For clay masonry,
1. Units must conform to ASTM C62, ASTM C216, or
ASTM C652 and are to be sampled and tested in
accordance with ASTM C67.
2. Thickness of bed joints does not exceed 5/8 in.
3. For grouted masonry, the grout meets one of the
following requirements:
 Grout conforms to ASTM C476.
 Minimum grout compressive strength (determined
by ASTM C1019) equals f 'm but is not less than
2,000 psi*.
Slide 19
Unit Strength
Method Applicability
 For concrete masonry,
1. Units must conform to ASTM C55 or ASTM C90 and
are sampled and tested in accordance with ASTM
C140
2. Thickness of bed joints does not exceed 5/8 inch.
3. For grouted masonry, the grout meets one of the
following requirements:
 Grout conforms to ASTM C476
 Minimum grout compressive strength (determined
by ASTM C1019) equals f 'm but is not less than
2,000 psi
Slide 20
Masonry Compressive Strength
Unit Strength Method
Specified compressive strength of clay masonry, f’m
Net area compressive
strength of
clay masonry, psi (MPa)
1,000 (6.90)
1,500 (10.34)
2,000 (13.79)
2,500 (17.24)
3,000 (20.69)
3,500 (24.13)
4,000 (27.58)
Net area compressive strength of
clay masonry units, psi (MPa)
Type M or S mortar
Type N mortar
1,700 (11.72)
2,100 (14.48)
3,350 (23.10)
4,150 (28.61)
4,950 (34.13)
6,200 (42.75)
6,600 (45.51)
8,250 (56.88)
8,250 (56.88)
10,300 (71.02)
9,900 (68.26)
—
11,500 (79.29)
—
Slide 21
Unit Strength Method
Specified compressive strength of concrete masonry, f’m
Net area compressive
strength of
concrete masonry, psi (MPa)
1,700 (11.72)
1,900 (13.10)
2,000 (13.79)
2,250 (15.51)
2,500 (17.24)
2,750 (18.96)
3,000 (20.69)
Net area compressive strength of
concrete masonry units, psi (MPa)
Type M or S mortar
Type N mortar
--1,900 (13.10)
1,900 (13.10)
2,350 (14.82)
2,000 (13.79)
2,650 (18.27)
2,600 (17.93)
3,400 (23.44)
3,250 (22.41)
4,350 (28.96)
3,900 (26.89)
----4,500 (31.03)
-----
1. Enter the table in these columns,
knowing the masonry unit compressive
strength and mortar type
2. Move across to the far left column
to determine what f’m you should
expect
TMS 402 Part 1 General
Requirements

Ch. 1: Scope, Contract documents and calculations,
Special Systems, Reference Standards

Ch. 2: Notation, Definitions

Ch. 3 Quality & Construction
Slide 23
Quality Assurance:
TMS 402 Chapter 3

Requires a quality assurance program in
accordance with the Specification


three levels of quality assurance (A, B, C)
increasing levels of quality assurance require
increasingly strict requirements for inspection, and for
compliance with specified products and execution
Slide 24
Article 1.6 – Quality assurance

Quality assurance requirements address


inspection
tests and submittals

The TMS TMS 402/602 addresses three levels of
quality assurance (minimum requirements!)

Increasingly severe levels of quality assurance:



Level A – TMS 402 Table 3.1.1 & TMS 602 Table 3
Level B - TMS 402 Table 3.1.2 & TMS 602 Table 4
Level C - TMS 402 Table 3.1.3 & TMS 602 Table 5
Slide 25
Quality Assurance/Special Inspection
Requirements depend on:

Type of Structure


Design/Detailing Method


Formerly “Importance”, then Occupancy Category, now
Risk Category
Prescriptive or Engineered
Criticalness of construction being considered

Items having a bigger impact of structural capacity or
where there is a bigger chance that something could go
wrong may need continuous special inspection version
other that may need only periodic special inspection
Slide 26
Minimum Inspection/Testing:
Types of Special Inspection

Items having more of an impact of structural capacity
or where there is a higher probability that something
could go wrong may need more rigorous inspection:


Continuous special inspection: full-time observation of work
while in progress, by an approved special inspector who is
present in the area where the work is being performed.
Periodic special inspection: Part time or intermittent
observation of work as specified, by an approved special
inspector who is present in the area where the work is being
performed and at the completion of the work.
Note that on a job, both types of inspection may be required
for different aspects of the project.*
Slide 27
Inspection & Testing
Requirements
Type of Facility
Risk (Occupancy) Category Risk (Occupancy) Category
I, II, III
IV (Essential)
Design
method
Prescriptive
Engineered
Prescriptive Engineered
Inspection
(IBC)
Exempt
Use TMS
per 1705.4 402/602
Use TMS
402/602
Use TMS
402/602
Inspection
(TMS
402/602)
Level A*
Level B
Level C
Level B
* No site inspection is required for Level A
Slide 28
Level B Special Inspection
Requirements: TMS 402 Table 3.1.2

At start of construction, verify:

On a Periodic basis:

Mortar proportions

Mortar joint construction



Location of reinforcement and
connectors
Prestressing technique, materials
Properties of thin-bed mortar for
AAC Masonry
Slide 29
Level B Special Inspection
Requirements: TMS 402 Table 3.1.2

During construction, inspect:

On a Periodic basis:






Continuously


Size, location of structural elements
Type, size, location of anchors
Size, grade, and type of reinforcement
Hot and cold weather construction
Application and measurement of
prestress force
Welding of reinforcing bars
Placement of AAC masonry units & thinbed mortar (first 5000 ft2 continuous, and
then periodic)
Slide 30
Level B Special Inspection
Requirements: TMS 402 Table 3.1.2

Prior to grouting, verify:

On a Periodic basis:




Grout space is clean
Reinforcement and tendon
placement
Grout proportions (site
prepared)
Mortar joint construction
Slide 31
Level B Special Inspection
Requirements: TMS 402 Table 3.1.2

During construction, verify:

Continuously




Grout placement
Grouting prestress tendons
Preparation of grout, mortar,
prism specimens
Application of prestressing
Slide 32
Level C Special Inspection
Requirements: TMS 402 Table 3.1.3

On a Periodic basis:

Proportions of mortar, grout & prestressing grout

Placement of units and mortar joint construction
Placement of reinforcement, connectors and prestressing
tendons & anchorages
Size and location of structural elements




Size, grade, type of reinforcement, anchor bolts and
prestressing tendons & anchorages
Hot and cold weather protection
Slide 33
Level C Quality Assurance: TMS
402 Table 3.1.3

Observe preparation of
grout and mortar
specimens and prisms
(if required)

Verify compliance with
required inspection
provisions and approved
submittals
Slide 34
Level C Special Inspection
Requirements: TMS 402 Table 3.1.3

Continuously:








Grout space prior to grouting
Grout placement
Prestress grout placement
Type, size, and location of anchorages
to structural members and frames.
Welding of reinforcement
Application & measurement of prestress force
Placement of AAC masonry
Preparation of grout, mortar, prism specimens
Slide 35
TMS 402 (& IBC) QA Requirements
Required Tests and Submittals
Masonry material certificates
Verify f ‘m & f ‘aac prior to
construction**
Level A*
Level B
Level C
•
•
•
•
•
Verify f ‘m & f ‘aac every 5,000 sq.
ft. during construction**
•
Verify proportions of materials in
premixed or preblended mortar &
grout
•
Verify slump flow & VSI of SCG
*Exempt from IBC
•
•
Periodic Continuous
** For Engineered masonry and not for Veneer, Glass United Masonry or Empirically Designed Masonry
Slide 36
General TMS 602 Special Inspection
Requirements for “Traditional” Masonry*
Minimum Special Inspection for Traditional Masonry* Level A Level B Level C
Verify compliance with approved submittals
PT
PT
PT
Verify proportions of site-prepared mortars
Construction of mortar joints
Placement of masonry units
Location of reinforcing, connectors and anchorages
-
PT
PT
PT
PT
PT
PT
FT
Grout space (prior to grouting)
Grade, type, and size of reinforcing, anchor bolts & anchorages
-
PT
PT
FT
FT
-
PT
PT
FT
FT
-
PT
PT
PT
FT
FT
FT
Verify proportions of site-prepared grout
Size, type & location of attachments to other structural elements
Size and location of structural elements
Observe preparation of prisms and grout or mortar specimens
Grout Placement
* Does not include Prestressed masonry, Hot & Cold Weather requirements, etc. Refer to MSJC for specific Requirements
•PT – Part Time or Periodic
FT – Full Time or Continuous
Slide 37
TMS 402 Parts 1 & 2
Part 1
Part 2

Ch. 1 General


Ch. 2 Notation &
Definitions
Ch. 4 General Analysis &
Design Considerations

Ch. 5. Structural Elements

Ch. 6 Reinforcement
Metal Accessories &
Anchor Bolts

Ch. 7 Seismic design
requirements

Ch. 3 Quality &
Construction
Slide 38

Restricts pour height
based on width/space
minus horizontal
reinforcement which
restricts the space
Grout Pour
Grout space
requirements in Table
3.2.1 are intended to
provide adequate
room for placement of
grout.
Grout Lift

Grout Lift
Construction:
TMS 402 Section 3.2
Slide 39
TMS 402 Part 2
Design Requirements

Ch. 4: General Analysis &
Design Considerations






4.1 Loading
4.2 Material properties
4.3 Section properties
4.4 Connections to structural
frames
4.5 Masonry not laid in
running bond

Ch. 6: Details of
reinforcement, metal
accessories & anchor bolts

Ch. 7 Seismic design
requirements
Ch. 5: Structural Elements
Slide 40
Loading: TMS 402 Section 4.1

must have continuous load path

design loads from governing building code or
ASCE 7 - 10

must have lateral force – resisting system

must consider load transfer at horizontal
connections

must consider effects of differential movement

lateral loads must be distributed according to
member stiffnesses
Slide 41
Most Masonry Buildings
Shear Wall/Diaphragm Systems
Walls parallel to lateral forces
act as shear walls to resist
in-plane loads; they may
resist axial loads
Bond beams transfer reactions
from walls to horizontal
diaphragms (floors and roof),
and act as diaphragm chords
Walls perpendicular to lateral forces resist moments
from out-of-plane loads and transfer reactions to
horizontal diaphragms; they may resist axial loads
Slide 42
Material Properties:
TMS 402 Section 4.2

Chord modulus of elasticity, shear modulus,
thermal expansion coefficients, and creep
coefficients for clay, concrete and AAC masonry

Moisture expansion coefficient for clay masonry

Shrinkage coefficients for concrete masonry and
AAC masonry
Slide 43
Section Properties for strength:
TMS 402 Section 4.3

Use minimum (critical) net area for computing
member stresses or capacities. Capacity is
governed by the weakest section; for example,

Minimum face shell thickness of hollow units if face
shell bedded only (typical)

Include area of grouted cores for grouted masonry for
shear, axial compression and in–plane compression
Out of plane flexural compression typically stays in
Slide 44
face shell

Section Properties for stiffness:
TMS 402 Sections 4.3.2 and 4.3.3

Radius of gyration and member slenderness are
better represented by the average section; for
example

the net area of units (face shells and webs) even if the
units are only face shell bedded

For partially grouted and solid grouted masonry, also
include grout area
Slide 45
Bearing Area:
TMS 402 Section 4.3.4

Direct bearing area A1

Modified bearing area A2 based on the
intersection of a 45 – degree truncated pyramid
with the edge of the element. See TMS 402
Section 4.3.4 and Commentary Fig. CC-4.3-2 for
definitions of A1 and A2.
Bearing Area  A1
A2
 2 A1
A1
Slide 46
TMS 402 Part 2
Design Requirements

Ch. 4: General Analysis &
Design Considerations

Ch. 5: Structural Elements





5.1 Masonry assemblies
5,2 Beams
5.3 Columns
5.4 Pilasters
5.5 Corbels

Ch. 6: Details of
reinforcement, metal
accessories & anchor bolts

Ch. 7 Seismic design
requirements
Slide 47
Wall intersections:
TMS 402 Section 5.1.1
nominal flange
thickness, t
50%
interlocking
units
L = 6 t for compression or
unreinforced masonry in
tension
L = 3/4 floor - to - floor wall effective flange
height for reinforced
length, L
masonry in tension
wall to the right
of movement
joint not part of
flange of web
wall
movement
joint
Slide 48
Effective compression width per
bar: TMS 402 Section 5.1.2

For running - bond masonry, or masonry with bond
beams spaced no more than 48 in. center – to –
center, the width of compression area per bar for
stress calculations shall not exceed the least of:



Center - to - center bar spacing
Six times the wall thickness (nominal)
72 in.
Slide 49
Distribution of concentrated loads,
running bond: TMS 402 Section 5.1.3.1

The critical area for walls laid in running bond shall
not exceed the wall thickness times the smaller of:


Length of bearing area plus a length determined by a
dispersion of 2 vertical: 1 horizontal. That dispersion is
limited by the smallest of one - half the wall height, a
movement joint, the end of the wall, or an opening.
Center – to – center distance between concentrated
loads
Slide 50
Distribution of concentrated loads,
running bond: TMS 402 Section 5.1.3.1
Load
Load
Load
1
2
h
2
h/2
1
Effective Length
Effective Effective
Length Length
Slide 51
Distribution of concentrated loads,
running bond: TMS 402 Section 5.1.3.1
Load
1
Load
1
2
Effective
Length
2
Effective
Length
Slide 52
Distribution of concentrated loads,
other than running bond

It is assumed that loads are not transferred across
vertical head joints

Compression stresses are calculated using a
smaller critical area of masonry

TMS 402 Section does not specify, but Code
Commentary continues to use a 2: 1 dispersion.
Slide 53
Distribution of concentrated
loads under bond beams

TMS 402 Section does not specify, but Code
Commentary continues to use a 2: 1 dispersion.

It is assumed that loads are not transferred across
vertical head joints.
Slide 54
Distribution of conc. loads under
bond beams: TMS 402 Section 5.1.3
Bearing Plate
Check bearing
on hollow wall
Load
Load
Bond Beam
Bearing Plate
Bond Beam
Load is
dispersed
at a 2:1
slope
Running bond
Load dispersion
terminates at head
joint in stack bond
Stack bond
Slide 55
Composite versus noncomposite
construction: TMS 402 Section 5.1.4

Multiwythe walls have more than one wythe of
masonry

Multiwythe walls may be designed for:


composite action, or noncomposite action
Composite action requires that collar joints be:

crossed by connecting headers, or filled with mortar or
grout and connected by ties
Slide 56
Composite action
TMS 402 Section 5.1.4.2

Composite action permits use of composite section
properties in analysis and design

Composite action is assumed to transfer loads and
provide continuity of deformations, without slip,
across collar joints

TMS 402 Section limits shear stresses on collar
joints or headers
Slide 57
Stresses with composite action,
Code Commentary - Fig. CC – 5.1-7
collar joint filled
lateral
load
Tens.
Comp.
lateral
load
Assumed
stress
distribution in
multiwythe
walls
of composite
masonry
Vertical Bending
Horizontal Bending
tension normal to bed joints
tension parallel to bed joints
Slide 58
Noncomposite action:
TMS 402 Section 5.1.4.3

Collar joints may not contain headers, grout, or
mortar

Horizontal in-plane loads and gravity loads
applied to one wythe are to be resisted by that
wythe only

Weak–axis bending moments, however, are
distributed to each wythe in proportion to its
flexural stiffness
Slide 59
Stresses with noncomposite action,
Code Commentary - Fig. 5.1-8
collar joint open
lateral
load
Comp.
Tens.
Comp.
Tens.
lateral
load
Assumed
stress
distribution in
multiwythe
noncomposite
walls
Vertical Bending
Horizontal Bending
tension normal to bed joints
tension parallel to bed joints
Slide 60
Max. 1¼ in. (31.8 mm)
Required spacing of Adjustable Ties
for Non-Composite Masonry
16 in. (406 mm) Max. Vert. Spacing
1.77 Sq. Ft. (0.16 m2)
Maximum Wall Surface
Area Per Tie
Max. Clear.
1/
16 in. (1.6 mm)
Vertical Section
/16 in. (4.8 mm) Wire
3
Tie Location
16 in. (406 mm) Max.
Horiz. Spacing
Spacing of Adjustable Ties
Eye Unit
Pintle Unit
Plan View
Slide 61
Prescriptive Requirements for
Beams: TMS 402 Section 5.2
Lintel Block
or Cut Unit
Shore
Slide 62
Prescriptive Requirements for
Beams: TMS 402 Section 5.2

Span length equals clear span plus depth, but not
more than distance between support centers

Moments for continuous beams based on center to - center spans

Minimum bearing distance = 4 in.

Lateral support on compression face required at a
maximum spacing of 32 times the beam thickness
(nominal) but no more than 120b2/d

Must meet deflection limits of TMS 402 Section
5.2.1.4
Slide 63
Deep Beams
Beam
depth
Alternative
beam
depth
00
leff
leff
Slide 64
Prescriptive Requirements for
Columns: TMS 402 Section 5.3

Old requirements changes in
2013 TMS 402



aspect ratio of cross – section  3
height > 4 times smaller cross –
sectional dimension
Columns are defined in TMS
402 Section 5.3



ISOLATED member that primarily
resists compressive loads
h / r  99
Minimum side dimension: 8 in.
Slide 65
TMS 402 Section 5.3 – Prescriptive
Requirements for Columns

Columns are not:



wall segments between openings (these are not
“isolated”)
pilasters (these are not “isolated”)
piers (these are defined for strength design as isolated
elements that meet certain dimensional limitations )
Slide 66
Distinction between Columns and
Pilasters

Pilasters are thickened
sections of masonry walls,
are not isolated members,
and are not columns

Pilasters need not be
reinforced

If pilaster capacity includes
the effect of compression
reinforcement, that
reinforcement must be tied
laterally
Slide 67
TMS 402 Section 5.3 – Prescriptive
Requirements for Columns

Cross – sectional dimension  8 in.

h / r  99



Minimum design eccentricity = 0.1 x
t
0.25%  g  4.0%
At least 4 longitudinal bars, laterally
tied, except for the strange case of
lightly loaded columns (for
example, columns in a “car port”
that primarily resist tension)
Slide 68
Column Ties
 16 times the vertical bar diameter
Tie
spacing
 Tie spacing may not exceed:
 48 times the tie diameter
 The least dimension of the column
 First tie at ½ tie spacing from
footing or slab
 Last tie at ½ spacing from support
Slide 69
TMS 402 Part 2
Design Requirements

Ch. 4: General Analysis &
Design Considerations

Ch. 5: Structural Elements

Ch. 6: Details of
reinforcement, metal
accessories & anchor bolts

Ch. 7 Seismic design
requirements
Slide 70
Details of Reinforcement:
TMS 402 Section 6.1

reinforcing bars must be
embedded in grout; joint
reinforcement can be
embedded in mortar

placement of
reinforcement

protection for
reinforcement

standard hooks
Slide 71
Anchor Bolts:
TMS 402 Section 6.2

Headed bolts, J - bolts or
L - bolts

Must be embedded in
grout
Slide 72
Anchor Bolts:
TMS 402 Section 6.2

Tensile capacity governed by

tensile breakout
 tensile pullout
 yield of anchor in tension
Shear capacity governed by

shear breakout
 masonry crushing
 shear pryout
 yield of anchor in shear
For combined tension and shear, use linear
interaction


Slide 73
TMS 402 Section Commentary - Fig.
CC-6.2-1
Tensile breakout failure of masonry
Tension Force
lb
assumed cone for
calculation of Apt,
Equation 6-1
lb
45° conical
failure
surface
Apt   
Tension Force
45° conical
failure
surface
2
b
Slide 74
Effective embedment length, lb
TMS 402 Section 6.2.4 and 6.2.5

Plate and headed bolts


embedment measured perpendicular from the masonry
surface to bearing surface of plate or head of bolt
Bent anchors

embedment measured perpendicular from masonry
surface to bearing surface of bent end, minus one anchor
bolt diameter
Slide 75
TMS 402 Section Commentary Fig. CC-6.2-7
Shear breakout failure of masonry
Shear Force
Apv 

2
 2be
45
Apv
lbe
Slide 76
TMS 402 Part 2
Design Requirements

Ch. 4: General Analysis &
Design Considerations

Ch. 5: Structural Elements

Ch. 6: Details of
reinforcement, metal
accessories & anchor bolts

Ch. 7 Seismic design
requirements
Slide 77
Seismic Design:
TMS 402 Chapter 7

Applies to all masonry except


Walls must either be



isolated from the seismic force - resisting system
classified as shear walls
Objective is to improve performance of masonry
structures in earthquakes



glass unit masonry and veneer
improves ductility of masonry members
improves connectivity among masonry members
Requirements for AAC masonry differ slightly
Slide 78
Seismic Design:
TMS 402 Chapter 7

Assign a structure’s Seismic Design Category
(SDC) according to ASCE 7 - 10


SDC depends on seismic risk (geographic location),
risk category (importance), underlying soil
SDC determines



required types of shear walls (prescriptive
reinforcement)
prescriptive reinforcement for other masonry
elements
permitted design approaches for LFRS
Slide 79
Seismic Design:
TMS 402 Chapter 7

Seismic design requirements
are based on ASCE 7 - 10
Seismic Design Categories
(from A up to F)

Requirements are
cumulative; requirements in
each “higher” category are
added to requirements in the
previous category
Slide 80
Minimum Reinforcement, Shear
Wall (SW) Types
SW Type
Minimum Reinforcement
SDC
Empirically
Designed
none
A
Ordinary Plain
none
A, B
Detailed Plain
Vertical reinforcement = 0.2 in.2 at corners, within 16
in. of openings, within 8 in. of movement joints,
maximum spacing 10 ft; horizontal reinforcement W1.7
@ 16 in. or #4 in bond beams @ 10 ft
A, B
Ordinary
Reinforced
same as above
A, B, C
Intermediate
Reinforced
same as above, but vertical reinforcement @ 4 ft
A, B, C
Special
Reinforced
same as above, but horizontal reinforcement @ 4 ft,
and  = 0.002
any
Slide 81
Seismic Design:
TMS 402 Chapter 7

Seismic Design Category A



drift limit of 0.007 from ASCE 7 - 10 (Section 12.12.1)
for typical masonry structures
minimum design connection force for wall - to roof
and wall - to - floor connections from ASCE 7 - 10
(Section 12.11.2)
Seismic Design Category B

lateral force – resisting system cannot be designed
empirically
Slide 82
Seismic Design:
TMS 402 Chapter 7

Seismic Design Category C


Shear walls must meet minimum prescriptive
requirements for reinforcement and connections
(ordinary reinforced, intermediate reinforced, or
special reinforced)
Other walls must meet minimum prescriptive
requirements for horizontal or vertical reinforcement
Slide 83
Requirements for Detailed Plain SWs
and SDC C: TMS 402 Section 7.3.2.3
roof connectors
@ 48 in. max oc
roof
diaphragm
#4 bar (min) within
16 in. of top of parapet
Top of Parapet
#4 bars around
openings
#4 bar (min)
within 8 in. of
corners &
ends of walls
24 in. or 40 db
past opening
#4 bar (min) @
diaphragms
continuous
through control
joint
#4 bar (min)
within 8 in. of
all control joints
control joint
#4 bars @ 10 ft oc
#4 bars @ 10 ft oc or W1.7 joint
reinforcement @ 16 in. oc
Slide 84
Seismic Design:
TMS 402 Chapter 7

Seismic Design Category D




Masonry that is part of the lateral force – resisting
system must be reinforced so that v + h  0.002,
and v and h  0.0007
Type N mortar and masonry cement mortars are
prohibited in the seismic force – resisting system
Shear walls must meet minimum prescriptive
requirements for reinforcement and connections
(special reinforced)
Other walls must meet minimum prescriptive
requirements for horizontal and vertical reinforcement
Slide 85
Requirements for Special Reinforced
Shear Walls: TMS 402 Section 7.3.2.6
roof connectors
@ 48 in. max oc
roof
diaphragm
#4 bar (min) within
16 in. of top of parapet
Top of Parapet
#4 bars around 24 in. or 40 db
openings
past opening
#4 bar (min)
within 8 in. of
corners &
ends of walls
#4 bar (min) @
diaphragms
continuous
through control
joint
#4 bar (min)
within 8 in. of
all control joints
control joint
#4 bars @ 4 ft oc
#4 bars @ 4 ft oc
Slide 86
Seismic Design Categories E and
F: TMS 402 Section 7.4.5

Additional reinforcement requirements for masonry
not laid in running bond and used in
nonparticipating elements



Horizontal Reinforcement of at least 0.0015 Ag
Horizontal Reinforcement must be no more than 24 in.
oc.
Must be fully grouted and constructed of hollow open-end
units or two wythes of solid units
Slide 87
Limit Design – Appendix C

New to 2013 TMS 402

Alternative Design Method for Special Reinforced
Shear Walls

Useful for design of complex, perforated wall
configurations
Good for traditional methods
Where direct design can help
Slide 88
Limit Design: Seismic Design of
Reinforced Masonry Structures

Combines…

Linear-Elastic Analysis
(conventional) to identify potential
yield mechanisms.



Using Force - based design (ASCE
7 - 10)
Emphasizes strength
Displacement based design in
considering component deformation
capacity
Slide 89
Force-based Seismic Design
Limitations

uncoupled cantilever walls are easy
to design

coupled cantilever walls are more
difficult to design

walls with arbitrary openings may be
impossible to design rationally
Slide 90
Limit Design: Seismic Design of
Reinforced Masonry Structures

Design Methodology

Seismic Analysis > Yield Mechanism > Verify Strength and Displacement
vs.
Full Structure Hinging
Base Hinging
Slide 91
Limit Design: Seismic Design of
Reinforced Masonry Structures

Design Considerations


Yielding and non-yielding components are detailed to
achieve desired ductility or strength, respectively
Joints are detailed to develop adequate moment capacity
for yielding wall components


Use of shear reinforcement in both direction
Locating lap splices of flexural steel outside of plastic
hinge zones, otherwise design for overstrength
Slide 92
Limit Design: Seismic Design of
Reinforced Masonry Structures

Impact on Design

Reduced flexural reinforcement


Relevant ductility checks


Compared against traditional design methodology
Focus on expected yield zones over prescriptive code
ductility requirements
Simple Approach


Based off of conventional seismic load
Direct Calculation of control mechanism (no iteration)
Slide 93
Allowable – Stress Design:
TMS 402 Chapter 8

fundamental basis

Anchor bolts

Shear stress limits on
multi-wythe walls

development and
splices of
reinforcement

unreinforced masonry

reinforced masonry
Slide 94
Allowable – Stress Design:
TMS 402 Chapter 8

fundamental basis

Anchor bolts

Shear stress limits on
multi-wythe walls

development and
splices of
reinforcement

unreinforced masonry

reinforced masonry
Slide 95
Allowable Tensile capacities for
Anchor Bolts: TMS 402 Sec. 8.1.3.3

tensile breakout Headed Bolts and Bent Bar
Bab  1.25 Apt

f m'
(8 - 1) and (8 - 3)
tensile pullout Bent bar
Bap  0.6 f ed d b  120  lb  ed  d b  d b
'
m

(8 - 4)
steel yield Headed Bolts and Bent Bar
Bas  0.6 Ab f y
(8 - 2) and (8 - 5)
Slide 96
Allowable Shear capacities for
anchor bolts: TMS 402 Sec. 8.1.3.3.2
Same for Bent Bars and for Headed Bolts
 shear breakout
Bvb  1.25 Apv

(8 - 6)
f Ab
(8 - 7)
masonry crushing
Bvc  350

f m'
4
'
m
shear pryout
Bvpry  2.0 Bab  2.5 Apt

f m'
(8 - 8)
steel yield
Bvs  0.36 Ab f y
(8 - 9)
Slide 97
Allowable – Stress Design:
TMS 402 Chapter 8

fundamental basis

Anchor bolts

Shear stress limits on
multi-wythe walls

development and
splices of
reinforcement

unreinforced masonry

reinforced masonry
Slide 98
Stresses with composite action
8.1.4.2 Shear stresses developed at the
interfaces between wythes and collar
joints or within headers shall not exceed
the following:
(a) mortared collar joints, 7 psi (48.3 kPa).
(b) grouted collar joints, 13 psi (89.6 kPa).
(c) headers,1.3 (specified unit
compressive strength of header
Psi)1/2 (MPa) (over net area of header).
Slide 99
Development of reinforcement
embedded in grout: TMS 402 Sec. 8.1.6

Required embedment length in tension
addresses splitting from bar to surface and bar
to bar
ld 

0.13 d b2 f y 
K
f m'
 12 in. (bars) , 6 in. (wires) (8 - 12)
For epoxy – coated bars or wires, increase the
above values by 50%
Slide 100
Development of reinforcement
embedded in grout: TMS 402 Sec. 8.1.6

Other requirements for flexural reinforcement

Equation (8-12) used for lap splices

Can decrease lap splice using confining steel.
  1 .0 
2
2.3 Asc
fy 
db
2 .5
(8 - 13)
Slide 101
ASD Unreinforced Masonry:
TMS 402 Section 8.2

8.2.1
Scope

8.2.2
Design Criteria

8.2.3
Design Assumptions

8.2.4
Axial compression and flexure

8.2.5
Axial Tension

8.2.6
Shear
Slide 102
Ratio of Wall Strength to
Compressive Strength of Masonry
Code Commentary Fig. CC - 8.2-1
1.2
(test results)
1.0
0.8
2

70r



 
 h  


2

h


l  
 
  140r  


0.6
Slenderness
affects axial
compressive
strength
0.4
fit to test data
stability
failure
0.2
0
h/t
0
5
10
15
20
25
30
35
40
45
h/r
0
25
50
75
99
125
150
Slide 103
Allowable axial compressive
stress: TMS 402 Section 8.2.4

Depends on slenderness (h / r)
2

 h  
h
1 '
  for  99
Fa    f m 1  
r
 4    140 r  
 1   70 r 
Fa    f m' 

4  h 

2
for
h
 99
r
(8 - 16)
(8 - 17)
Also requires a stability check
P  (1 / 4) Pe
Pe 
(8 - 15)
 Em I 
2
h
2
e
1  0.577 
r

3
(8 - 19)
Slide 104
Allowable Flexural Stresses of
URM: TMS 402 Section 8.2.4

Flexural compression
1 '
Fb    f m
3

Flexural tension (Table 8.2.4.2)





out - of - plane bending (traditional values)
lower values for masonry cement and air - entrained
portland cement - lime mortar
higher values for grouted masonry
Factors of safety around 2.5
Values for in – plane and out - of - plane flexural
tension are equal
Slide 105
Linear interaction for combined
loads: TMS 402 Section 8.2.4.1

Members subjected to combined flexure and
axial compression shall satisfy TMS 402
Equation (8-14)
fa
fb

1
Fa Fb
(8 - 14)
Slide 106
Shear for unreinforced masonry:
TMS 402 Section 8.2.6

Calculated shear stress
VQ
fv 
In b

(8 - 20)
Allowable stress is lowest of
1 .5
f m'  120 psi
Nv
  0.45
An
Where  = 37 psi running bond or not running bond and
fully grouted, = 60 psi for running bond and grouted , and =
15 psi otherwise
Slide 107
Shear for unreinforced masonry:
TMS 402 Section 8.2.6.3

Normalized web area on concrete masonry units
(ASTM C140) must not be less than 27 in2/ft2 or
you must check shear stresses in the web do not
exceed 1.5 f m'
Slide 108
Rational Design of Load – Bearing
Walls – Also must account for holes
in wall and span direction

gravity and out – of – plane loads are resisted
by combinations of horizontal and vertical
strips
vertical
strips
roof diaphragm
horizontal
strips
ALLOWABLE STRESS (ASD) DESIGN
URM WALLS – OUT OF PLANE AND
IN- PLANE VERTICAL LOADS
If Load bearing
there is a vertical
load May be
eccentrically
Applied
Roof/floor
Diaphragm
Supports Wall
ASD Design of Unreinforced Walls Out-of-Plane Ex1a – MDG TMS 14
111
On Board
ASD Design of Unreinforced Walls Out-of-Plane Ex1b – MDG TMS 14
113
On Board
ASD Design of Unreinforced Walls Out-of-Plane Similar to Ex MDG
TMS
115
On Board
ASD Design of Unreinforced Walls Out-of-Plane Ex1 – MDG TMS
Revised from text – Strength level wind loads – Higher Allowables
f’m = 1500 psi
Wind load = 23. psf
Strength Level (ASCE 7-10)
Mortar Type TBD
Design Walls
20’
Note that actual max
moment is slightly
lower than mid-span –
But code allows you to
look at mid-span
16.67’
ASD Design of Unreinforced Walls Out-of-Plane Ex1 –
ASSUME THE AXIAL LOAD IS 650 lb/ft DEAD
LOAD and the rest LIVE LOAD
Converted joist reaction to per ft load
And assume Strength level Wind load is 23 psf
e found by assuming the bearing conditions shown
Mwind= 23. plf x (3.33)2/2 x 12in/ft = 1530.3 lb.in
Mwind = (- 1530.3 lb.in/2 + (23 plf x (16.67)2/8) x
12in/ft) = 8057 lb.in
M at top due to axial load
1530.3 lb.in
M DL = 650 x 2.48” = 1612 lb.in,
M LL = 400 x 2.48” = 992 lb.in
at mid-height ½ these values
M= ½ Pe
8057 lb.in
+?
Check Shear!
Critical Locations
Top of wall
Mid-height
Bottom of wall (rarely)
Look at all load combinations but
D+(L or S or Lr)
OR D + .75(L or S or Lr) +.75 (.6W or .7E)
OR 0.6 D + (.6W or .7E) usually critical
Check bearing under load (D+L) - assume a 4” x 6” bearing plate
fbr= P/A1 = 1050 / (4 x 6) = 43.5 psi (average) < ¼ (1500) = 375 psi
Most people will assume code implies this is an average stress even though it’s
inconsistent with e calculation
Check axial Stress under load (D+L) top of wall just under parapet and
load since it may be critical - it must be less than Fa.
Parapet weight
Or use Tek note 14-01B
39.4 psi is less than 280 psi
therefore fa ≤ Fa OK
note that D+L load combo is critical at this level for this check - no other
combos needs to be addressed
Check top of wall (D+L)
For net flexural tension fbt= -fa+fb ?
fb (D+L) = (MDL + MLL)/S = (1612+992)/81 = 31.2 psi
fbt= -39.4+31.2 = -7.9 psi (still in compression therefore OK)
Check D + .75 L + .75 (0.6W) at the top (this produces more tension stress-most times)
fa= -(650+400 x 0.75)/30 = - 31.7 psi
fb= (1612+0.75 x 992+ 0.75 x 0.6 x1530.3)/81 = 37.6 psi
fbt= -fa+fb = -31.7 + 37.6 psi = 6.1 psi
Ft = ? Lowest allow. for Type N masonry cement normal to bed joints hollow = 12 psi
Any mortar will work – OK So far ft ≤ Ft (See Table 8.2.4.2)
Should also check fb ≤ Fb = 1/3 f’m = 1500/3 = 500 psi
(all are well below this value) Bending OK at this level
Check Stability at Top - D+L always governs since it is always determined using the
eccentricity (e) associated with the axial loads only
Check Stability at Top - D+L
P ≤ ¼ Pe based on 1 ft design width again
P = 1050 lb
Check Stability at Top - D+L
Pe = π2 (900 x 1500) (334)/(16.67 x 12)2 x [1-0.577 (2.48/2.84)]3 = 13582 lb
¼ Pe = 3395 lb > 1050 lb therefore OK
Note we could reduce the applied e by accounting for the concentric axial weight of the
parapet – e effective at top = M/P = (1612+992)/(1050 + 3.33 x 40) = 2.20 in.
Check Combined Compression Stresses D +.75 L + 0.75 (0.6)W or D + L critical ? Too close
check both
fa/Fa + fb/Fb ≤ 1
= 39.4/280 + 31.2/500 = 0.202 (D+L) less than 1 OK
fa/Fa + fb/Fb ≤ 1
= 31.7/280 + 37.6/500 = 0.19 (D+.75L+.75(0.6W)) less than 1 OK
Check Mid-height of the Wall
Again we should check stability but the top is more critical and there is no bearing check
Check axial stress at wall base (more critical - later)
Here just check bending and combined stresses.
Bending (normally check 0.6D+0.6W & D + 0.75L+ 0.750(0.6W) – the first load case governs
for tension
fb(wind) = (0.6 x 8057) /81.0 = 59.7 psi, fb(dead)= 650(2.48/2)(0.6)/81.0 = 5.97 psi
fa(dead) = (650 + 11.67 x 40)/30 = 37.2 psi x 0.6 = 22.32
Ft = -22.32+ 59.7 +5.97 = 43.3 psi >> than 33 psi allowable I could get for PCL Type S
What do we do?
1. Put more concentric axial load on the wall
2. Make the wall thicker
3. Grout the wall
4. Reinforce the wall
Lets try 3
Check Mid-height of the Wall - solid grouted 8” wall
Again we should check the top again but it worked hollow, it will work solid.
Bending (normally check .6D+0.6W & D + 0.75L+ 0.75(0.6W) – first load case governs for
tension
S= 116.3 in3
fb(wind) = (8057)/116.3 = 69.8 psi , fb(dead)= 650(2.48/2)(0.6)/116.3 = 4.16 psi
fa(dead) = (650 + 11.67 x 78)/(12 x 7.625) = 17.1 psi
Ft = -17.1 (0.6) + 0.6 x 69.8 +4.16 = 35.8 psi < than 77 psi allowable (Type N Masonry cement)
OK
Check combined bending and axial compression D+.75L+.75 (0.6W)
Fb = 500 psi
h/r = (16.67 x 12)/2.2 = 90.9
Fa = .25 (1500) [1- 16.67(12)/(140 x2.2)]2= 329 psi
(17.1 + .75 (400)/(12x7.625) )/329 + [69.8 x 0.75 x0.6+ (650+.75 x 400) x 2.48/2/116.3]/500
= 0.063 + 0.083 = 0.15 <<<1.0 therefore OK
You should check the base of the wall for fa < Fa - (maximum value for fa)
however the critical load combination is D + L and increasing the axial stress by 1 psi for
each foot of height (~17 psi) results in fa ~ 60 psi <<< Fa= 329 psi.
Check Top of Wall for Shear- solid grouted 8” wall
(normally check .6D+0.6W & D + 0.75L+ 0.75(0.6W) –
V wind = 23 x (20 x 10)/16.67 = 275.9 lb
V dead = 1612 lb.in/ (16.67(12)) = 8.06lb
V (.6D+0.6W) = 165.5 lb
fv = VQ/Ib at max (solid rectangle) = 3/2 (165.5)/(7.626 x 12) = 2.71 psi
This is much smaller than the critical allowable
Fv = v + .45 Nv/An = 37 psi + .45 Nv/An OK
USE A SOLID GROUTED 8in CMU WALL with TYPE N MASONRY CEMENT MORTAR
IT WOULD MOST LIKELY BETTER TO REINFORCE OF THE WALL
MORE LATER!!!!
ASD Design of
Unreinforced Walls loaded laterally
In-Plane – Shear
Any vertical loads are going to cause the Wall to bend outof-plane so check wall as described previously for OOP
Lateral Load for roof or floor
Length of wall = L
Applied parallel to wall
length
h
Base Shear
Over turning moment
Just look at in-plane bending and shear
ASD Design of
Unreinforced Walls loaded In-Plane
1) Check Bending (flexural stresses)
Flexural Tension almost always governs

ft = My/I ft max = M/S = Flexural tensile stresses usually govern
design ≤ Ft flexural compression fb= My/I , fb max = M/S

Note that the depth of section is now , d= L and width, b, is t (for
solid) or t faceshell

Remember that for out-of-plane t = depth of section and b =
effective length of wall.

Note Ft in-plane ignores flashing. May not be conservative. May
want to use Ft = 0.

Also check fb ≤ Fb = (1/3) fm’
ASD - Shear for Unreinforced
Masonry In-Plane
2) Check Shear fv = VQ/Ib ≤ Fv
(As before for out-of-plane plane)

Fv = Allowable In plane stress (Can also be used for outof-plane - conservative) and is lowest of :
'
1.5 fm
 120 psi
Nv
  0.45
An
ASD Design of
Unreinforced Walls In-Plane
•
•
Do examples of Unreinforced Wall
Design
Leave room for notes on the following
examples done on board
131
ASD Design of
Unreinforced Walls loaded laterally
In-Plane
Lateral Load for roof or floor
Length of wall = L
Applied parallel to wall
length
h
Base Shear
Over turning moment
132
ASD Design of
Unreinforced Walls In-Plane
20 ft 16.67 ft
Wind
17 psf
30 ft
30 ft
133
ASD Design of
Unreinforced Walls In-Plane
Reaction to shear wall = 204 x 30/2
1 ft Design Width
= 3060 lb
Uniform Load at Roof diaphragm
Produced by wall spanning to roof
= Load = 17 lb/ft x 20’ x 20’/2 (1/16.67’)
20 ft 16.67 ft
= 204 lb/ft
Wind
30 ft
17 psf
30 ft
134
ASD Design of
Unreinforced Walls In-Plane
Lateral Load for roof or floor
Length of wall = L= 30 ft
Reaction to shear wall = 3060 lb
16.67
f
t
Over turning moment = 3060 x
16.67 ft = 51,010 lb.ft
135
On Board
Assume 8” Hollow block (CMU) wall with a weight of 37 psf
Check base of wall for flexure - Assume Face shell bedded
Bending (normally check .6D+0.6W & D + 0.75L+ 0.75(0.6W) – first load case governs for
tension
Section modulus - you have two strips 1.25” wide going the full length of the wall.
So S = 2 x1.25 (30 x 12)2/6 = 54000 in3
fb(wind) = (0.6) x51,010 x 12/54000 = 0.6 x11.33 = 6.8 psi
fa(dead) = 20 x37x30/(30 x 12x(1.25+1.25)) = 24.67 psi
ft= = -24.67( (0.6) +6.8 = -8.0 psi
Still in compression so any mortar would be OK.
Check combined bending and axial compression D+.75L+.75 (06W)
Fb = 500 psi
h/r = (16.67 x 12)/2.84 = 70.5 (same as before – for Out-of-plane)
Fa = .25 (1500) [1- 16.67(12)/(140 x2.84)]2= 280 psi
fa = 24.67 psi since all dead load and only wind produces flexure so fb = 0.75 (6.8)
Thus fa/Fa+fb/Fb = 24.67/280+.75(6.8)/500 =
= 0.088 + 0.010 = 0.098 <<<1.0 therefore OK .
No applied load at top of wall so no stability check needed
Check shear
Shear is constant over the height of the shear wall and we want to check
the greatest shear load under the lowest axial load (gives lowest
capacities)
By inspection 0.6D+0.6W will give the above conditions at the top of the wall
Two rectangular strips go the full length of the wall and are essentially two thin rectangular
sections 1.25 in wide. So we can say the maximum shear stress=
fs(max wind) =VQ/Ib = 3/2 (V)/An = 3/2 (3060) / (2.5)(30 x12) = 5.1 psi x 0.6 = 3.06 psi
Allowable Shear = Fv = ? = The smallest of the following
1.5
f m'  120 psi  1.5 1500  58.1 psi  120
  0.45
Nv
 37  0.45(0)  37 psi governs  7.5 psi
An
OK in Shear Use a 8" Hollow CMU Face shell bedded
Any mortar is likely wor k but the assumption s for the compressio n
stress check assumed Type S masonry Cement for Determinat ion
of f' m