Tips for optimizing structural masonry

TIPS TO OPTIMIZE STRUCTURAL MASONRY

presented by International Masonry Institute

INTERNATIONAL MASONRY INSTITUTE

APPRENTICESHIP & TRAINING

MARKET DEVELOPMENT & TECHNICAL SERVICE

ILLINOIS STRUCTURAL MASONRY COALTION

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© International Masonry Institute 2010

Copyright Materials

This presentation is intended for the use of industry professionals who are competent to evaluate the significance and limitations of the information provided herein. This publication should not be used as the sole guide for masonry design

and construction, and IMI disclaims any and all legal responsibility for the consequences of applying the information.

IMI is a Registered provider with the American Institute of Architects Continuing Education Systems. Credit earned on completion of this program will be reported to CES Records for AIA members. Certificates of Completion for non-AIA members are available on request. This program is registered with the AIA/CES for continuing professional education. As such, it does not include content that may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or any method or manner of handling, using, distributing or dealing in any material or product. Questions related to specific materials, methods and services will be addressed at the conclusion of this presentation.

Learning Objectives

• Understand interrelationship between masonry materials, architecture, engineering, and construction.

• Learn how a few simple decisions can lead to more efficient and economical structures.

• Discover some non-traditional structural masonry materials and systems.

• Apply code, specification and standards provisions appropriately.

Using masonry for the

building’s structural support

– Bearing walls

– Shear walls

– Combination bearing & shear

– Hybrid!

– Partition walls (not structural)

Theater at Ostia Antica, Rome c. 200 AD

Colosseum, Rome, c. 80 AD

Versatile structural system

Fast, efficient & economical

Masonry may be on the project already – use it structurally!

Finish trade – so tighter tolerances are held

No lead time for production, review and approval of shop drawings

Adapts easily to field changes –

“with masonry you just pick up the phone and

the change can be done”

Local materials, local employment

Using material efficiently – one material for structure, finish, fire resistance, blast resistance, acoustics and more…

Masonry is “Green”

And it looks good too!

Get started right… MSJC Documents

Building Code Requirements for Masonry Structures TMS 402-08 / ACI 530-08 / ASCE 5-08

Specification for Masonry Structures TMS 602-08 / ACI 530.1-08 / ASCE 6-08

International Building Code 2009

ASTM Masonry Standards

More than 75 under the masonry committees jurisdiction

Another 15 new ones under development Narrow down to a few basic ones

Materials

Concrete Masonry Units

Tip 2 – Use the right ASTM Standard

ASTM C 90 Standard Specification for Loadbearing Concrete Masonry Units

Use for projects requiring loadbearing CMU

Sets minimum requirements

Include the edition Example: ASTM C 90-09

Defaults to version referenced by local building code if not specified

Tip 3 – Unit Compressive Strength & Density

ASTM C 90-09 Table 2 Compressive strength requirements are independent of

unit density

Example: Lightweight units are required to meet the same compressive strength minimum requirements as Medium weight and Normal weight units

Tip 4 – Remember, Minimum Requirements

ASTM C 90-09 Minimum compressive strength requirements in Table 2 No maximum compressive strength limit

Permissible to specify higher unit strength which leads to

higher compressive strength for the masonry wall

Check local availability before specifying higher

strength units

Tip 5 – Specify Above C90 Minimum Strength

If higher strength units are available, the effect on the structural design can be significant

Often very little, if any cost penalty for units with strengths above the ASTM C 90 minimum

May already be on the job – so use what you already have!

for example…

Tip 5 – Specify above C90 Minimum Strength

Checking the test report

Tip 5 – Specify Above C90 Minimum Strength

Finding the average unit compressive strength

Tip 5 – Specify Above C 90 Minimum Strength

Unit Strength Method to determine Masonry Compressive Strength

3067

ASTM C90 Minimum unit strength

Average unit compressive strength from testing report

2140

Tip 5 – Specify Above C 90 Minimum Strength

Masonry Compressive Strength Options

Increase the compressive strength of masonry Check actual compressive strength of the units Specify higher compressive strength units Consider prism testing on larger projects Consider larger width units if necessary

MORTAR

© 2009 INTERNATIONAL MASONRY INSTITUTE

ELEVATIONS

DIAGRAM 01.410.0311 REV. 08/10/09

MORTAR JOINT MATERIAL TAKEOFF

UTILITY BRICK, RUNNING BOND MODULAR BRICK, RUNNING BOND

4 @ 12” x 3/8” = 18.000 SQ. IN. BED JOINTS

HEAD JOINTS 8 @ 2.3125” x 3/8” = 6.938 SQ. IN.

2 @ 1.3125” x 3/8” = 0.984 SQ. IN.

25.922 SQ. IN. MORTAR

3 @ 12” x 3/8” = 13.500 SQ. IN.

3 @ 3.625” x 3/8” = 4.078 SQ. IN.

17.578 SQ. IN. MORTAR

18.00% MORTAR 12.21% MORTAR

ONE SQUARE FOOT ONE SQUARE FOOT

18% 12%

COLORED MORTAR

MORTAR

ASTM C 270

Mortar Options:

- Portland Cement and Lime

- Masonry Cement

- Mortar Cement

Mortar Types: M, S, N,

and O

Mortar Quality Control

ASTM C 270 MASONRY MORTARS

MORTAR

M S N O K r w o a

ASTM C 270 MASONRY MORTARS

MORTAR

ASTM C 270 TABLE 1 – PROPORTION SPECIFICATION

MORTAR

ASTM C 270 TABLE 2 – PROPERTY SPECIFICATION

MORTAR

M S N O K

general ratio

cement : lime : sand

1:½:4½

1:1:6 1:2:9 1:3:12 1:¼:3¾

Refer to ASTM C 270 for acceptable ranges

PROPORTION RULES-OF-THUMB

MORTAR

MIXING BY HAND

MORTAR

Preblended grout mixed from dry ingredients in silo

PREBLENDED MORTAR & GROUT

TEMPERING

MORTAR

Materials

Masonry Grout

STANDARD SPECIFICATION FOR GROUT FOR MASONRY

ASTM C476-10

Grout is NOT mortar NOR

concrete and is a cementitious

material unique to masonry.

• Grout can be mixed on-site or

obtained from transit or Redi-mix

suppliers.

• Grout can be placed by hand

or pumped with specifically

designed grout pumps.

• Grout quantities can be

determined from reference

charts such as the one shown on

the next slide.

GROUT

6”

Thick Walls

All Cells Filled

16” o.c.

24” o.c.

32” o.c.

40” o.c.

48” o.c.

0.93

0.55

0.42

0.35

0.31

0.28

0.83

0.49

0.37

0.31

0.28

0.25

120

205

270

320

360

396

8”

Thick Walls

All Cells Filled

16” o.c.

24” o.c.

32” o.c.

40” o.c.

48” o.c.

1.12

0.65

0.50

0.43

0.37

0.34

1.00

0.58

0.44

0.38

0.33

0.30

100

171

225

267

300

330

10”

Thick Walls

All Cells Filled

16” o.c.

24” o.c.

32” o.c.

40” o.c.

48” o.c.

1.38

0.82

0.63

0.53

0.47

0.43

1.23

0.73

0.56

0.47

0.42

0.38

80

137

180

214

240

264

12”

Thick Walls

All Cells Filled

16” o.c.

24” o.c.

32” o.c.

40” o.c.

48” o.c.

1.73

1.01

0.76

0.64

0.57

0.53

1.54

0.90

0.68

0.57

0.51

0.47

65

111

146

174

195

215

Standard

Two Cell

Block

Grouted Cells

Vertical Steel

Spacing

Cu. Yds. Of

Grout Per 100

Sq. Ft. of Wall

Cu. Yds. Per

100 Block

(8”h X 16”w)

Block Per Cu.

Yd.

(8”h X 16”w)

SCOPE ASTM C476-10

SCOPE ASTM C476-10

FINE & COARSE GROUT

Grout Specimen Fine Aggregate

Grout Specimen Coarse Aggregate

Conventional Grout

SCOPE ASTM C476-10

SCG

3. Materials

3.1.1 Cementitious Materials

3.1.1.1 Portland Cement

3.1.1.2 Blended Cements

3.1.1.3 Quicklime

3.1.1.4 Hydrated Lime

3.1.1.5 Coal Fly Ash or Raw Calcined

Natural Pozzolan

3.1.1.6 Granulated Blast Furnace Slag

3.1.2 Air Entraining Admixtures

3.1.3 Aggregates

3.1.4 Water

3.1.5 Admixtures

3.1.5.1 Admixtures for SCG

3.1.6 Pumping Aids

3.1.7 Antifreeze Compounds

3.1.8 Storage of Materials

MATERIALS

Clean & potable

iwr, accelerators, etc.

Not permitted

Protect from moisture

ASTM C476-10

water-reducers, viscocity modifiers

GROUT TYPE & PROPORTIONS

4. Grout Type and Proportions

4.1 Type

4.1.1 Fine grout

4.1.2 Coarse grout

4.2 Proportions of Ingredients

4.2.1 Conventional Grout

4.2.1.1 Table 1

4.2.1.2 Specified Compressive Strength

4.2.2 Self-consolidating Grout

4.2.2.1 Specified Compressive Strength

2,000 psi at 28 days

Per astm c1019

Fine aggregate

Coarse and Fine aggregates

24-30 in. slump flow;

2,000 psi at 28 days

Per astm c1019

Vsi < 1

ASTM C476-10

• Coarse grout is typically more economical than fine grout

and is usually preferred.

• Both coarse and fine grout can be designed to achieve

necessary strength requirements.

• Space consumed by mortar fins must be subtracted from

the clear space.

• Minimum clear cross-sectional dimensions of the cells to

be grouted are shown in the chart on the next slide.

FINE GROUT vs. COARSE GROUT

Table 3.1.2-Grout space requirements *

Grout type1

Maximum grout

pour height,

Ft.

Minimum width

of grout space,

In.

Minimum grout

space

dimensions for

grouting cells of

hollow unit

in. x in.

Fine

Fine

Fine

Fine

1

5

12

24

3/4

2

21/2

3

1 ½ x 2

2 x 3

2 ½ x 3

3 x 3

Coarse

Coarse

Coarse

Coarse

1

5

12

24

1 ½

2

2 ½

3

1 ½ x 3

2 ½ x 3

3 x 3

3 x 4

* MSJC Code

FINE GROUT vs. COARSE GROUT

1/2” MAX.

MORTAR FIN

MORTAR PROTRUSION TOLERANCE

DIAGRAM 02.410.0121 REV. 02/22/09

MORTAR FINS

Mortar Fins (protrusions)

Mortar fins restrict the flow of grout

into cells and can actually trap air.

They must be removed before

grouting takes place. The best time

to do this is during wall construction.

MORTAR FINS

MASONRY PRISM

Masonry Prism Sectioned prism, (2) CMU,

Mortar Joint, Grout, Rebar

MASONRY PRISM

Masonry Prism Sectioned prism, (2) CMU,

Mortar Joint, Grout, Rebar

However, remaining fins should be broken free

and dropped to the cleanouts and removed before

grouting takes place.

Proper technique in the application of mortar and

the setting of the CMU should minimize mortar

fins.

MORTAR FINS

Grout should be able to flow completely

around the rebar.

Clearance must be provided between the:

• Face shells of the CMU

• Other rebar

Masonry & grout coverage also protects

the rebar from corrosion or weather.

MINIMUM MASONRY COVER

1 1/2 inch minimum cover for interior face.

2 inch minimum cover for exterior

face exposed to earth or weather

MINIMUM MASONRY COVER

.

1/2” MIN. FOR COURSE GROUT 1/4” MIN. FOR FINE GROUT

MINIMUM DISTANCE FROM ANY PROTRUSION:

REINFORCEMENT PLACEMENT TOLERANCE

DIAGRAM 02.410.0123 REV. 02/22/09

MINIMUM GROUT CLEARANCE

MINIMUM GROUT CLEARANCE

MSJC 2008 Specification for Masonry Structures

“Grout compressive strength equals or exceeds f’m but not less than 2000 psi.” (Article 1.4 B.2.a.3)b) and 1.4 B.2.b.3)b))

“Grout compressive strength equals or exceeds f’aac but compressive strength is not less than 2000 psi.” (Article 1.4 B.c.3)b))

“unless otherwise required, provide grout that conforms to the requirements of ASTM C 476, or ” (Article 2.2 A.1)

“…attains the specified compressive strength or 2000 psi, whichever is greater, at 28 days when tested…” (for self-consolidating grout) (Article 2.2 A).2)

ASTM C 476-10 Standard Specification for Grout for Masonry

“…and shall have a minimum compressive strength of 2000 psi at 28

days.” (Section 4.2.1.1 (Conventional grout))

…”The grout shall have a minimum compressive strength of 2000 psi at

28 days.” (Section 4.2.2.1 (Self-consolidating grout))

GROUT TYPE & PROPORTIONS ASTM C476-10

STANDARD TEST METHOD FOR SAMPLING AND TESTING GROUT

ASTM C1019-09

SCOPE; SIGNIFICANCE & USE ASTM C1019-09 1. Scope

1.1 This test method covers

procedures for both field and

laboratory sampling and

compression testing of grout used

in masonry construction.

3. Significance & Use

3.1 Grout used in masonry is a fluid

mixture of cementitious materials

and aggregate with a high water

content for ease of placement.

3.1.1 During construction,

grout is placed within or

between absorptive masonry

units. Excess water must be

removed from the grout

specimens in order to provide

compressive strength test

results more nearly indicative of

the grout strength in the wall.

TEST SPECIMENS ASTM C1019-09 PROCEDURES

5. Test Specimens

5.1 Each grout specimen shall

have a square cross section,

3 in. or larger on the sides and

twice as high as its width.

5.2 Test at least three specimens

at each age specified.

Note 4: frequency of sampling and

age of test is to be determined by

the specifier, and is usually found

in the construction documents; for

example, one set of specimens may

be specified for every 5,000 s.f. of

wall.

EXAMPLE: IF SPECIMENS ARE TO BE

TESTED AT 7, 14, AND 28 DAYS, THEN

MAKE 9 SPECIMENS.

GROUT SPECIMEN MOLDS ASTM C1019-09

SCOPE ASTM C1019-09 6. Grout Specimen Molds

6.1 Molds from Masonry Units

6.1.1 Select a level location where the molds

remain undisturbed for up to 48 hours.

6.1.2 The construction of the mold shall simulate the

in-situ construction. If the grout is

placed between two different types of

masonry units, both types shall be used to

construct the mold.

6.1.3 Form a space with a square cross-section,

3 in. or larger on each side and twice as high

as its width, by stacking masonry units of the

same type and moisture condition as

those being used in the construction. The

surface of the unit in contact with the grout

specimen shall not have been previously

used to mold specimens. Place non-

absorbent block, cut to proper size and of the

proper thickness or quantity, at the bottom of

the space to achieve the necessary height of

specimen.

5% tolerance on dims.

Filling Slump Cone

Hold cone firmly

in position so grout

does not escape while filling the cone.

Slump cones are for testing grout

consistency prior to grouting.

SLUMP TEST, CONVENTIONAL GROUT

1/3

Fill the bottom 1/3

and rod 25 times

with the puddle rod.

Straight in and

Straight out… do not

stir.

Filling Slump Cone


2/3

Fill the middle 1/3

and rod 25 times.

Penetrate bottom 1/3 only slightly.

Filling Slump Cone


3/3

Fill the top 1/3

and rod 25 times.

Penetrate middle 1/3 only slightly.

Filling Slump Cone


Grout should slump 8 to 11 inches.

Lift the cone slowly

and straight up. Do not twist or turn.

Remove Slump Cone


Conventional Grout

ASTM C 143

8 - 11” slump

SCG

ASTM C1611

24” to 30” slump flow

VSI < 1

SLUMP vs. SLUMP FLOW

ALTERNATIVE METHODS ASTM C1019-09

6. Grout Specimen Molds

6.2 Alternative Methods - … used

only with approval of the

specifier.

Note 7: fill compartments in

slotted corrugated cardboard

boxes specifically manufactured

to provide grout specimens.

CALCULATIONS ASTM C1019-09

11. Calculations

11.1 Determine the average cross-

sectional area by measuring the

width of each face at its mid-height,

calculating the average width of

opposite faces, and multiplying the

averages.

11.2 For specimens from molds of

masonry units, calculate the

compressive strength by dividing

the maximum load by the average

cross-sectional area and express

the result to the nearest 10 psi.

x2

x1

y1

y2

P

Average cross-sectional Area =

x1 + x

2

2 2

y1 + y

2 .

Tip 10 – Understand Grout Pours and Lifts

Often confused or used interchangeably. MSJC Definitions:

Grout Pour – The total height of masonry to be grouted prior to erection of additional masonry. A grout pour consists of one or more grout lifts.

Grout lift – An increment of grout height within a total grout pour. A grout pour consists of one or more grout lifts.

Maximum pour height – function of grout type (fine or coarse), minimum grout space dimensions, use of cleanouts, conventional grout or SCG. Maximum pour heights are established by MSJC Table 7.

Maximum lift height – default is 5’, may increase to 12’-8” under some circumstances. SCG may be increased to pour height under some circumstances.

1999 MSJC – 5’ lift height limitation.

2002 MSJC – demonstration panel option permitting any construction procedures that produce proper installation.

2005 MSJC – lift height increased to 12’-8” subject to conditions.

2008 MSJC – Self-consolidating grout provisions


Grout lift height –

A.) Where the following conditions are met, place grout in lifts not exceeding 12.67 ft

1.The masonry has cured for at least 4 hours.

2. The grout slump is maintained between 10 and 11 in.

3. No intermediate reinforced bond beams are placed between the top and the bottom of the pour height.

B.) As above but intermediate bond beam, then lift height can extend to the bottom of the bond beam but not to exceed 12.67’.

C.) Otherwise, place grout in lifts not exceeding 5 ft.

D.) Demonstration panel option may result in increases.

E.) SCG may, under some circumstances be permitted to have the grout lift equal the pour height.


LOW LIFT GROUTING

LOW LIFT GROUTING

LOW LIFT GROUTING

LOW LIFT GROUTING

LOW LIFT GROUTING

LOW LIFT GROUTING

LOW LIFT GROUTING

LOW LIFT GROUTING

LOW LIFT GROUTING

LOW LIFT GROUTING

LOW LIFT GROUTING

LOW LIFT GROUTING

LOW LIFT GROUTING

LOW LIFT GROUTING

LOW LIFT GROUTING

LOW LIFT GROUTING

HIGH LIFT GROUTING

HIGH LIFT GROUTING

HIGH LIFT GROUTING

HIGH LIFT GROUTING

HIGH LIFT GROUTING

HIGH LIFT GROUTING

HIGH LIFT GROUTING

HIGH LIFT GROUTING - SCG

Self Consolidating Grout Demonstration

LOW LIFT GROUTING PROCEDURES

DETAIL 02.410.0131 REV. 06/30/10

VERTICAL REINFORCEMENT FOR CLOSED-END CONCRETE MASONRY UNITS CAN BE SET AFTER WALL HAS BEEN LAID.

REBAR POSITIONER, WALL TIE, OR OTHER DEVICE TO POSTION VERTICAL REINFORCEMENT

HORIZONTAL REINFORCEMENT PLACED IN BOND BEAMS AS WALL IS LAID UP

METAL LATH, MESH, OR WIRE SCREEN PLACED IN MORTAR JOINTS UNDER KNOCK-OUT BOND BEAM COURSES TO PREVENT FILLING OF UNGROUTED CELLS

OPTION 2: STANDARD CMU W/ CROSS WEBS KNOCKED OUT AT BOND BEAM COURSE

OPTION 1: U-BLOCK UNITS W/ SOLID BOTTOM AT BOND BEAM COURSE

GROUT IN BOND BEAMS & REINFORCED VERTICAL CELLS PLACED IN TOP OF WALL AFTER WALL HAS BEEN LAID UP

STOP GROUT 1” FROM TOP OF POUR TO CREATE SHEAR KEY

CELLS CONTAINING REINFORCEMENT ARE FILLED SOLIDLY W/ GROUT; VERTICAL CELLS SHOULD PROVIDE A CONTINUOUS CAVITY FREE OF MORTAR DROPPINGS

NOTE: GROUT PLACED IN POURS & LIFTS NOT TO EXCEED 5 FT. CONSOLIDATE LIFTS OVER 12” USING MECH. VIBRATION. LIFTS LESS THAN 12” MAY BE PUDDLED.

HIGH LIFT GROUTING PROCEDURES

DIAGRAM 02.410.0131 REV. 07/06/10

VERTICAL REINFORCEMENT FOR CLOSED-END CONCRETE MASONRY UNITS CAN BE SET AFTER WALL HAS BEEN LAID.

REBAR POSITIONER, WALL TIE, OR OTHER DEVICE TO POSTION VERTICAL REINFORCEMENT

HORIZONTAL REINFORCEMENT PLACED IN BOND BEAMS AS WALL IS LAID UP

METAL LATH, MESH, OR WIRE SCREEN PLACED IN MORTAR JOINTS UNDER KNOCK-OUT BOND BEAM COURSES TO PREVENT FILLING OF UNGROUTED CELLS

OPTION 2: STANDARD CMU W/ CROSS WEBS KNOCKED OUT AT BOND BEAM COURSE

OPTION 1: U-BLOCK UNITS W/ SOLID BOTTOM AT BOND BEAM COURSE

GROUT IN BOND BEAMS & REINFORCED VERTICAL CELLS PLACED IN TOP OF WALL AFTER WALL HAS BEEN LAID UP

STOP GROUT 1” FROM TOP OF POUR TO CREATE SHEAR KEY

CELLS CONTAINING REINFORCEMENT ARE FILLED SOLIDLY W/ GROUT; VERTICAL CELLS SHOULD PROVIDE A CONTINUOUS CAVITY FREE OF MORTAR DROPPINGS

NOTE: GROUT LIFTS NOT TO EXCEED 5 FT. SEE STRUCTURAL DWGS FOR MAX. HEIGHT OF POUR. MECH. CONSOLIDATE & RECONSOLIDATE GROUT

CLEANOUT OPENINGS @ BASE OF VERTICALLY REINF. CELLS, 32” O.C. MAX. SPACING FOR SOLID GROUTED WALLS. REMOVE MORTAR DROPPINGS THROUGH CLEANOUTS AND VERIFY PLACEMENT & LOCATION OF VERTICAL REINF.; FORM OVER OPEN’GS BEFORE PLACING GROUT

Tip – Consider Cleanout options

Multiple options for cleanout construction

Does not have to be a full face shell high Minimum size is 3”

Can be concealed easily on interior walls with base molding

Cleanout

BRACE CLEANOUT AND PLACE GROUT

CUT PORTION OF FACE SHELL TO CREATE CLEANOUT

REINSERT FACE SHELL AND MORTAR IN PLACE

PLACE REINFORCING AND INSPECT WALL FOR OBSTRUCTIONS

REMOVE BRACING

BLOCK CLEANOUT

DIAGRAM 02.410.0111 REV. 06/12/09

CUT FACE SHELL FOR CLEANOUT

WOOD BRACING

GROUT & REINFORCEMENT

BLOCK CLEANOUT

DIAGRAM 02.410.0112 REV. 06/12/09

REINSERT FACE SHELL PIECE TO RESIST GROUT PRESSURE

CUT WEDGE-SHAPED PORTION OF FACE SHELL TO CREATE CLEANOUT

CLEANOUT

MORTAR FACE SHELL EDGES IF NECESSARY

BLOCK CLEANOUT

DIAGRAM 02.410.013 REV. 06/12/09

1. CUT OUT PORTION OF FACE SHELL

2. PLACE ACRYLIC GROUT STOP INTEGRALLY BRACED AGAINST INSIDE OF FACE SHELL

3. HAND-TIGHTEN BRACE

5. REMOVE ACRYLIC AND BREAK OFF PLASTIC BRACE

4. PLACE REBAR & GROUT

BLOCK CLEANOUT

DIAGRAM 02.410.0114 REV. 06/12/09

Tip 11 – Give the Contractor Some Latitude

Give the contractor some latitude in the….

Selection of Fine or Coarse Grout Technical considerations

Grout space dimensions

Pour height limitations

Compressive strength independent of type

Constructability considerations Ease of use/Personal preference

Cost implications – material, placement

Issues related to pour height (next slide)

Fine Grout might be better suited here

Coarse or Fine Grout here

Tip 11 – Give the Contractor Some Latitude

Give the contractor some latitude in the….

Determination of Pour and Lift height

Technical considerations Code/Spec compliance

Inspection options

Other

Constructability considerations Cleanouts

Bracing

Site constraints

Coordination of trades

Placement procedures

Other

Tip 11 – Give the Contractor Some Latitude Give the contractor some latitude in the….

Use of self-consolidating grout

Technical considerations New material comfort level

Grout spaces and pour heights

Inspection and testing capabilities

Local supplier experience

More

Constructability considerations Cost

Availability

Experience with the product

Grout space/height

• More

SLAB EDGE

SLAB EDGE

FOUNDATION DOWELS

VERTICAL REINFORCEMENT AS REQ’D

GROUT AS REQ’D

HORIZONTAL JOINT REINFORCEMENT

CMU SHOWN IN LONGITUDINAL SECTION

DOWELS MAY BE BENT UP TO 1” LATERALLY PER 6” VERTICALLY

FOUNDATION

FOUNDATION DOWEL ALIGNMENT

DETAIL 02.010.0301 REV. 02/22/09

SPACING OF VERTICAL REINFORCEMENT

±1/2” IF d ≤ 8”

d

±1” IF 8”< d ≤ 24” ±1¼” IF d > 24”

±2”

REINFORCEMENT PLACEMENT TOLERANCE

DIAGRAM 02.410.0122 REV. 02/24/09

PARTITIONS

PARTITIONS

PARTITIONS

Innovations

Spanning the Opening

SPANNING OPENINGS

DOUBLE ANGLES AT BLOCK

SPANNING OPENINGS

Massive steel sections can be expensive and inefficient

STEEL BEAM and PLATE

LINTELS

LINTELS

LINTELS

SPANNING OPENINGS

CONCRETE MASONRY LINTEL

SPANNING OPENINGS

Poly-wrapped steel angles used for temporary support

CAST-IN-PLACE MASONRY LINTEL © 2009 INTERNATIONAL MASONRY INSTITUTE

SPANNING OPENINGS

Precast masonry lintel fabricated on the ground

PRECAST LINTELS © 2009 INTERNATIONAL MASONRY INSTITUTE

SPANNING OPENINGS

Lintel is hoisted by lift

PRECAST LINTELS © 2009 INTERNATIONAL MASONRY INSTITUTE


SPANNING OPENINGS

Precast lintel set into place

PRECAST LINTELS


SPANNING OPENINGS

10-foot span

PRECAST LINTELS

U-BLOCK CMU BOND BEAMS

DIAGRAM 02.410.0142 REV. 07/08/10

CMU BOND BEAM MADE FROM U-BLOCK UNITS


HORIZONTAL REINFORCEMENT AS REQ’D

U-BLOCK NOTCHED TO ACCEPT VERTICAL REINFORCEMENT

SPECIAL SHAPE U-BLOCK

KNOCK-OUT CMU BOND BEAMS

DIAGRAM 02.410.0141 REV. 07/08/10

VIEW OF STANDARD BLOCK BEFORE CROSS WEBS ARE KNOCKED OUT

VIEW OF BLOCK AFTER CROSS WEBS ARE KNOCKED OUT TO ACCOMMODATE HORIZONTAL REINFORCEMENT

METAL LATH, MESH, OR WIRE SCREEN PLACED IN BED JOINTS UNDER KNOCK-OUT BOND BEAM COURSES TO PREVENT FILLING OF UNGROUTED CELLS


HORIZONTAL REINFORCEMENT AS REQ’D

BOND BEAM

BOND BEAM

BOND BEAM

BOND BEAM

Structural Options & Efficiencies

Use masonry as

Lintels

Deep beams

INTERSECTING WALLS

VIEW OF INTERSECTING

BOND BEAMS PRIOR TO

GROUT PLACEMENT

LENGTH AS REQUIRED TO DEVELOP REINFORCEMENT

GROUT AND REINFORCING AS REQ’D

KNOCK OUT FACE SHELL OF BOND BEAM UNIT FOR CONT. GROUT & REINFORCEMENT

NOTE: SEE BUILDING CODE REQUIREMENTS FOR REINFORCEMENT DEVELOPMENT LENGTHS AND MINIMUM AREA OF REINFORCEMENT REQ’D

RAKE OUT MORTAR FOR CONTROL JOINT

FLANGE WALL

WEB WALL

RAKE OUT MORTAR FOR VERTICAL C.J.

INTERSECTING WALLS

DETAIL 02.120.1523 REV. 02/22/08

BOND BEAMS

FLANGE WALL

WEB WALL

CONTROL JOINT

50% INTERLOCKING UNITS REQ’D TO BOND WALLS

CONTROL JOINT


INTERSECTING WALLS

DETAIL 02.120.1521 REV. 02/22/08

50% INTERLOCKING UNITS

RAKE OUT MORTAR AND CAULK

GROUT STOP

WEB WALL

FLANGE WALL

MIN. 24” L x 1½” W x ¼” THICK Z-STRAP CONNECTOR W/ 2” EXTENSIONS EA. END

STEEL CONNECTOR

CONNECTOR EMBEDDED INTO GROUT-FILLED CORES @ EACH END


INTERSECTING WALLS

DETAIL 02.120.1522 REV. 02/22/08

STEEL CONNECTOR

Innovations

Hybrid Masonry

Options, options and more options!

Hybrid masonry/steel frame

Reinforced Masonry infill

Combined with structural steel frame

Masonry acts as bracing

Eliminates cutting infill around steel cross bracing

c) TYPE I HYBRID ∆= 0.02” (0.5 mm)

a) RIGID FRAME

10 KIPS W12x35

∆

W1

2x4

0

∆= 4” (100 mm) W8x24

W8

x1

5

W8

x1

5

10 KIPS

b) BRACED FRAME ∆= 0.04” (1 mm)

W8

x1

5

W8x24 10 KIPS

W1

2x4

0

W8

x1

5

Note detailing issues due to frame deflection

CMU cuts around brace not shown

GAPS 1, 2: NO IN-PLANE LOAD TRANSFER

GAP 2 GAP 1

GAP 3

TYPE I

BEAM OR GIRDER

COLUMN

SHEAR WALL

SHEAR (IN-PLANE)

GAP 3: TRANSFERS IN-PLANE SHEAR LOAD; NO AXIAL LOAD

COLUMN

GAPS 1, 2: NO IN-PLANE LOAD TRANSFER (SOFT JOINTS)

GAP 2 GAP 1

NO GAP

TYPE II

BEAM OR GIRDER

COLUMN

SHEAR WALL

SHEAR (IN-PLANE)

BEAM/GIRDER TRANSFERS IN-PLANE SHEAR LOAD

COLUMN

AXIAL LOAD

NO GAP NO GAP

NO GAP

TYPE III

BEAM OR

GIRDER

COLUMN

SHEAR WALL

SHEAR (IN-PLANE)

COLUMN

SHEAR

(IN-PLANE) SHEAR

(IN-PLANE)

AXIAL LOAD

not yet included in building codes

HYBRID MASONRY & STEEL



Garden Hills Elementary School, Champaign, IL BLDD Architects

Innovations

Structural Brick

Tip 14 – Consider Structural Brick

Reinforced hollow brick masonry

Reinforced structural veneer

Innovations

Loadbearing CMU Pilasters & Columns

SPECIAL SHAPE PILASTER BLOCK

CMU PILASTER W/ GROUT & REINFORCEMENT PER STRUCTURAL ENGINEER

REBAR POSITIONER

GROUTED CELLS PER STRUCTURAL ENGINEER

LOAD BEARING PILASTER

DETAIL 02.010.1101 REV. 06/17/08

REINFORCED COLUMN

REINFORCED COLUMN

REINFORCED COLUMN

REINFORCED COLUMN

REINFORCED COLUMN

Innovations Loadbearing AAC Masonry

AAC Craftworker Certification Training

Design provisions in Appendix A of MSJC

Strength Design provisions similar to MSJC Chapter 3

MSJC Specification contains construction provisions

IBC force resisting system limited to SDC A, B, C

IRC not limited

Locally adopted code may differ

Tip 15 – Consider AAC Masonry

8x8x16 normal

weight block

(140 pcf)

8x8x16 light

weight block

(105 pcf)

38 lbs 28 lbs

8x8x16 AAC

AC-4 block

(31 pcf)

18 lbs

UNIT WEIGHT COMPARISONS

14,000 s.f. addition

8” loadbearing AAC wall

12” loadbearing AAC wall

8”-12” T. x 8” H. x 24” L. AAC block have

one 4”Ø core to accept a #6 bar @ 24”

o.c.

LOADBEARING AAC MASONRY WALL

DETAIL 13.120.0101 REV. 04/23/10

12” THICK x 8” H. x 24” L. AC-4 AUTOCLAVED AERATED CONCRETE (AAC) MASONRY UNITS

JOIST GIRDERS @ 5’-0” O.C. PER STRUCTURAL

#6 VERTICAL REINFORCING & GROUT IN 4”Ø CORES @ 24” O.C.

16” H. BOND BEAM W/ (2) #5 REBAR @ EA. COURSE

NOTE: THIS DRAWING REPRESENTS A BASIC STRUCTURAL AAC MASONRY WALL; IT IS NOT INTENDED FOR CONSTRUCTION WITHOUT PROPER ENGINEERING DESIGN AND CALCULATIONS.

Reinforcement Splices & Options

Tip 16 – Include Splice Lengths in Project Documents

Question: Why should the splice lengths and locations be included on the project drawings?

Answer: The design professional has the information necessary to calculate lap lengths, the contractor does not. Contractors cannot be expected to know which lap length equation is applicable nor the variables that are included in some lap splice equations.

Consider that laps may vary based on:

Bar diameter

Design method (ASD or SD)

Locally adopted building code

Specified cover

Specified f’m

and more…

PLANK AT BEARING WALL

DETAIL 02.120.0751 REV. 11/25/08

INTERMEDIATE ELEVATION

2’-0 HORIZ. x 2’-0” VERT. #4 DOWELS AND GROUT AT PLANK KEYWAYS – SEE DETAIL 20.P02

3” MIN. BEARING & BEARING STRIP

BOND BEAM W/ (2) #5, CONT, OR AS REQ’D

GROUT PLANK SOLID AT BEARING

GROUT & VERTICAL REINFORCING AS REQUIRED

SOLID CMU

PRECAST CONCRETE PLANK

NOTE: VENEER & AIR/ MOISTURE BARRIER NOT SHOWN

HORIZONTAL. JOINT REINFORCEMENT

TOPPING IF REQ’D

LAP VERTICAL BAR SPLICE ABOVE PLANK LEVEL

#6 vertical bars in wall required 48 bar dia. lap length = 36 in.

SPLICE LENGTHS

#6 vertical bars in wall required 48 bar dia. lap length = 36 in.

SPLICE LENGTHS

Options to avoid long lap lengths: Use smaller diameter bars at closer spacing.

Cover distance is key – maximize cover for minimum lap lengths.

Minimize laps by permitting higher grout lifts

Use specified f’m, not just minimum value…

MSJC Equations & IBC SD requirements

Lap length INCREASES as: •Bar size increases, •Cover decreases

Lap length DECREASES as: •Bar size decreases, •Cover increases, •Masonry compressive strength increases

Tip 17 – Reduce Splice Length when Appropriate

Question: Which of the above is the better choice? Answer: Either one could be fine, so consider:

• Bar weight

• Quantity of grout and difficulty in placement

• Are lap splices being used (longer for the #6 bar)

• Generally smaller bars closer together produce more

cohesive behavior for the wall as a whole.

• But, too close together and more grout is needed.

• Is the wall going to be fully grouted for other reasons?

Tip 17 – Reduce Splice Length when Appropriate

Balance bar size & spacing to optimize the design, example:

#4 bar @ 24”c/c is equivalent to #6 bar @ 48”c/c

32” spacing Various spacing

24” spacing

REINFORCEMENT SPACING

Lap splices

Mechanical splices Becoming more common

Develop 125% of specified bar yield strength.

Welded splices Specify weldable reinforcement

Bars butted and must develop 125% specified bar yield strength.

Difficult, expensive, not recommended for most applications

Tip 18 – Consider other Splicing Options

Tip 19 – Think joint reinforcement not bond beams…

Joint reinforcement may be used to meet horizontal reinforcement requirements

Bond beams are more expensive option but may offer more steel reinforcement area

For crack control, joint reinforcement may not be needed with bond beams

Can use both in the building to suit different needs

Options, options and more options!

Prefabricated masonry

And even more….

Software for structural analysis

Bottom Line

Structural masonry…

Durable


Economical

Masonry as structure and finish



Sustainable


Fire & Blast Resistant


Think structural masonry for your next project

BAC CONTRACTORS

IMI-TRAINED CRAFTWORKERS

International Union of Bricklayers and Allied Craftworkers

International Masonry Institute

TIPS TO OPTIMIZE STRUCTURAL MASONRY

presented by International Masonry Institute

Tips for optimizing structural masonry

Education

higher strength units

c90 minimum strength

actual compressive strength

masonry design

higher unit strength

masonry wall

astm masonry standards

masonry structures tms