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S T R U C T U

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P R A C T I C E S

c) Quality craftsmanship by the masonto implement the design. This isnot just the aesthetics but, moreimportantly, the structural function.

Remember, a masonry building is handcrafted just like it was thousands of yearsago, one unit placed upon another.

Through the use of a widervariety of material and tech-nology such as reinforcedmasonry, we can accomplishgreat things with modernmasonry. But, the processof creating a building re-quires much more than theefforts of the mason.

Q What can structuralengineers do toimprove theirmasonry projects?

Mr. Painter: Here areseveral items that could beaddressed:

Mixing SystemsMasonry produces an excellent

load bearing system. However, we often are faced with a mixtureof reinforced concrete and struc-tural steel with the masonry

walls. As an example, Figure 1a shows a detail with a concretebeam formed by the masonry.The beam was intended to span

only 4 feet. Figure 1b shows therevised detail that accommo-dated the span and created thedesired brick soffit. The beamaction reverted from the concreteback to the masonry.There has also been a grow-

ing trend to using commerciallyavailable systems for steel lintels(Figure 2 ). While effective, thosesystems are often expensive. Ma-sonry lintels can often provide thestructure required at lower cost.

The message here is to select onesystem and stick to it! Wheneverpossible, use the masonry withoutinterjecting other materials. Themixing of structural systems cancreate coordination, schedulingand financial conflicts on abuilding project.Provide Detail Adjustability Veneer and hung masonry usu-

ally require steel support. Figure 3 shows a standard relievingangle detail available through the

14

Masonry Advice for Structural Engineers An Interview with Jerry M. Painter

In the arena of codes and standards,participation is dominated by engineers,architects, code officials and industryrepresentatives. Unfortunately, there arefew contractors and construction man-agers. However, there is one masoncontractor who has been striving for

improvements in both the design andconstruction of masonry. Mr. JerryPainter of Painter Masonry, Gainesville,Florida, has a 40 year history as a ma-son and contractor. The company worksthroughout Florida, and has a compan-ion firm, Painter Crane and Rigging, toservice its masonry business as well as theoverall construction industry.Mr. Painter is an active member of

The Masonry Society and its ExecutiveBoard, a member of the Masonry Standards

Joint Committee (MSJC) that producestheBuilding Code Requirements for MasonryStructures , (TMS 402/ACI 530/ASCE 6),and serves on numerous ASTM com-mittees. He is active in the MasonryContractors Association of America,the Masonry Association of Florida, theRotary Club of Gainesville, the AlachuaCounty Code Enforcement Board, andother civic groups. He lectures at variousuniversities. Clearly, this is a contractorthat sees the big picture!Mr. Painter sat down with STRUCTURE®

magazine, and gave his thoughts on variousmasonry issues that might help structuralengineers and architects improve theindustry for which he has dedicated hisprofessional career.

Q Can you tell us what youbelieve qualifies as “highquality” masonry?

Mr. Painter: High quality masonryhas four distinct characteristics. It must befunctional, economical, durable and aes-thetically pleasing. I believe it takes all fourof these to create “high quality” masonry.

Q Can you give us your thoughts onmasonry workmanship?

Mr. Painter: I believe work-manship as it relates to masonry applies toall aspects of the project. It includes:a) Proper design and material selection by

the architect and structural engineer.The easier it is to understand andaccomplish the design, the more likelyit is to be built correctly.

b) Preparation for construction by thegeneral contractor and mason thattakes into account field conditions.

Brick Industry Association. It includes slotted anchor in a concrete beam thaprovides vertical adjustability. Horizontally slotted angles allow for adjustmenin that direction. Shims are needed foadjusting outward. Remember, the masodoesn’t set these anchors. That’s the re

A1’- 8”

4”

B1’- 2”

Figure 1a.

CONC.

BEAM

DOVETAIL

EMBEDS

4 PER HEAD

STIRRUPS

GROUT

FILL

STRUCTURAL DE

FS403 DET 58 &

SHOW STEEL LIN

*

M..O. @ 3’ - 8d “ BRICK COURSING IS 3’ - 6e” & 3’ - 93”

DECREASE 16 JTS BY 7 /64" OR INCREASE JTS BY 1 /16"

Figure 1b.

Figure 2.



sponsibility of the concrete subcontractor.The mason is forced to accommodate the in-stallation of the embedded items.In recent years, structural engineers have

been using embedded weld plates or anglesbolted with adhesive anchors to the edgebeams. While these systems can adequatelysupport the masonry, alignment and adjust-ability are a concern. As with the embed-

ded anchors, embedded weld plates mustbe properly located in the concrete beams.They also don’t easily allow the steel to be

held in place for align-ment prior to welding.Shims are needed for ad-

justment.Drilled in adhesive bolts

have their own set of prob-lems. Maintaining align-ment during drilling is oneconcern. The other is the

potential for drilling intothe beam reinforcement.The mason has no controlover the reinforcement

placement but has to make the connection.Be aware that just because a detail is do-able

does not make it right. Accommodate Tolerances

The problems associated with the two itemsnoted above are exaggerated by industrystandards associated with different materials.Structural steel frames and concrete framesare to be constructed to the tolerances

of AISC and ACI respectively. However,the masonry skin is expected to be plumband level. This requires that the structuralengineer accommodate those variations intolerances by providing adjustability in theveneer support design. Also, be understanding of the mason. Mostdo not construct the foundations but areasked to accommodate the work of othertrades. Figure 4a shows a footing that wasnot properly formed, and the bars were mis-located. However, the mason is expected tobuild a plumb and level wall from this start-

ing point. The MSJC specifications requireinspection prior to placing the masonry.However, ACI 318 has tolerances for cast inplace concrete. Cooperation with the mason ingetting other trades to meet their own toleranc-es will only improve the quality of the masonry.Figure 4b shows a foundation wall with

alignment problems. Masons are good, butno mason can straighten this out. Mistakesmade by other trades should not be forcedupon a mason.Get Your !@#$%&@ Stuff Out of My Wall!Masonry walls must serve more than

structure. Figures 5a and 5b ( page 16 ) showbond beams that were detailed with electricalconduit. The conduit prevents completegrouting of the bond beam, interferes withthe reinforcement, and reduces that strengthof the beams.Figure 6 (page 16) shows a wall. What is the

bearing capacity of the wall with all the pipepenetrations? The MSJC code (Section 1.15.2of the 2005 edition) requires considerationfor the lost masonry. That forced the use of

FLASHING

WEEP HOLE

LIPPED BRICK

ELASTIC SEALANT

AND BACKER ROD

MIN.c IN. SPACE

LOW SHELF ANGLE

Figure 4a.

Figure 3. Courtesy of Brick Industry Association, Technical Note 18A.

Figure 4b.

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Figure 6.

developing masonry contractor certificatioprograms. The Mason Contractors Associatioof America (MCAA) is currently developing national certification program. There has alsbeen a renewed interest in apprenticeshipThe results of this can be seen in the classeand competitions at the local, state, regionaand national levels.

Figure 7.

ASTM has embarked on an effort to devel

op a new standard, The Standard Practice foUnit Masonry Workmanship. This documen

will provide minimum workmanship requirements for unit masonry construction (claand concrete masonry units) with the intento “standardize” finished wall construction. Iis to supplement the MSJC SpecificationsFor instance, there will be a more thorougdiscussion of construction tolerances a

well as provisions for a first-ever tolerancfor mortar joint “solidity”. Joint solidity ia reflection of how full the mortar joints arconstructed. Currently, there is no tolerance

This is unrealistic!Remember, masonry is a handcrafted system

constructed by people who are not perfect with materials that are not exact and withdesigns that are not always exact. Please allowfor tolerances and flexibility in the design andconstruction of the oldest and arguably stithe best building system known to man.STRUCTURE: Thank you for your com

ments! We hope all structural engineers witake your advice to heart and examine how theimplement masonry design and construction.▪

Jerry Painter is the President for Painter Masonry, Gainesville, Florida.

a steel header underneath the precast plankfloor to span over the openings. Further,Section 1.15.2.3 requires conduits and pipesto be separated by 3 diameters.Finally, Figure 7 shows a wall with so many

conduits and pipes that it’s hard to findthe reinforcement, or identify areas wheremasonry could be placed. The design had tobe changed to provide a chase.

Structural engineers need to advocate forrelocating the utilities from the groutedmasonry or creating chases. The structuralcapacity of bond beams must be of primaryconcern. In addition, Section 1.15.2.4 limitsthe area of vertical conduits and pipes to 2percent of the net area of the masonry section.It’s best to keep all this in the ungrouted cellsof the walls.Be Aware of Material PropertiesUnderstand that masonry consists of

“stacking pieces”. Those pieces are masonry

units, and each is unique with properties thatvary. Understand the interaction of brick,CMU, stone and other materials. They aren’tthe same! Provide details to accommodate thedifferences. The MSJC code and specificationrequires the locating of control joints inconcrete masonry be done by the designer,not the mason.Shop DrawingsReinforcement shop drawings are essential to

a quality project. Structural engineers shouldbe aware of who is preparing and checking

Figure 5a.

Figure 5b.

these drawings. Contractually, it may not bethe mason. In that case, the mason must beincluded on the review of the shop drawings.

Why? Because the method of grouting isdirectly related to the splice locations. Lowlift grouting splices must be carefully laidout and not made random. In addition, thesplice locations relative to features such asfloor lines are important to a mason. If thestructural engineer requires specific splicelocations, such as at retaining walls or shear

walls, those locations must be clearly notedrather than making the rebar detailer thedefault designer.Get the mason’s input to the shop drawings

and have them sign off.

Q You advocate for qualitycraftsmanship. How canstructural engineers and architects

promote that on projects?

Mr. Painter: There are two majorthings that can be done. Require mock-upsand provide quality assurance inspection.Mock-ups are often specified by the architect.

However, they should include architecturaland structural features including anchorsand ties. These should be built large enoughto show all standard conditions anticipated.Once accepted, don’t allow the mock-ups tobe moved or destroyed until the work hasbeen accepted.Thorough inspection by knowledgeable

inspectors is good for everyone! Structuralengineers should be sure their inspectors arefamiliar with industry standards, testing re-quirements and the design documents. Work

with the mason to resolve interferences or

problems, whether accidental or unintended.

Q What new efforts are underwayto continue improvingmasonry construction?

Mr. Painter : The masonry industryhas realized that we are losing masons fasterthan we are replacing them. The changes inmaterial and technology over the last 30-50years has shown us the need for more, andbetter educated and trained, masons. This isevident because several states either have or are

Mr. Painter was interviewed by DavidBiggs, P.E., Ryan-Biggs Associates, NY. Mr.Biggs specializes in the design, evaluationand restoration of masonry structures,forensic engineering, and the developmentof new masonry products. David was along-time member of the STRUCTURE® Editorial Board until January 2007.