Tel:(902)443-4456 Fax:(902)429-6696Web site: www.atlanticconcrete.caEmail: info@atlanticconcrete.ca

Atlantic Concrete Association (ACA)Association béton Atlantique (AbA)

(FormerlyAtlantic Provinces ReadyMixed ConcreteAssociation)Return undeliverable Canadian addresses to: below return address

30 Damascus Road, Suite 216 Bedford, NS Canada B4A 0C1

Publication Mail Agreement #41772012

AFFIX MAIL LABEL HERE

• WelcomeDouglasMurrin ofMurrinCo ReadyMix as theAssociation’s new BOD President.Doug, from beautiful Newfoundland andLabrador, will serve in this position for twoyears.

• We are sad to announce the departure ofColin Dickson,P.Eng., EMBA fromCAC. Colinserved the Atlantic Region for many yearsproviding technical expertise and advice tothe Cement and Concrete sectors and alsosat onACA’s BOD. Colin is now a principal ofIndustrial Engineering Systems where hepractises consulting engineering.Michael Lioof Lafarge Canada now represents the Ce-ment Industry on our board andwewelcomehim as a new director.

• Thank-you to Shane MacDow of PinnacleAgencies for his valuable service on theBoard as our Associate Director. Shanestepped down this year and we now wel-come Steven Peters from Euclid Canada toserve as our Associate rep.

• Farewell to Gerard Gaudet who steppeddown from the ACA BOD this year. Gerardheld the office of past president. David Ban-croft of OSCO has now stepped into this po-sition and we welcome his continuingguidance as we move forward into the fu-ture.

• WelcomeMichel Binette LL.B.,MPA, as CACVice President,Quebec andAtlantic Regions.Michel bringsmore than 20 years experiencein government relations, federal, provincialand municipal public affairs as well as pub-lic administration.Michel was at the Office ofthe Delegate Minister of Natural Resourcesand Wildlife Quebec, where he served asChief of Staff for the past two years, over-seeing federal, provincial and territorial rela-tions, as well as strategic planning. Prior tothis,hewas SpecialAdvisorwith the Office ofthe Deputy Premier and the Minister of Mu-nicipalAffairs and the Regionswhere hewasresponsible for the management of infra-structure programs, provincial water policyand loan regulations. From 2005 to 2008,heserved as Executive Director of the Munici-pality of SaintAdolphe d’Howard,overseeingits administration.

• We welcome new associate member AtelierGerard Beaulieu (AGB).AGB is based in SaintQuentin, New Brunswick and manufacturesreplacement mixer drums. Atelier can bereached at (506) 235-2243.

SPRING 2011

A t l a n t i c C o n c r e t e A s s o c i a t i o n • A s s o c i a t i o n b é t o n A t l a n t i q u e

Ready Mix Briefs

Construction of a new processing facility forVale (formerly Voisey’s BayNickel) at LongHarbour in Newfoundland is well under-

way and, by all accounts, expected to be com-pleted on time and on budget

An environmental assessment report was re-leased inAugust 2008.Work on the plant began inApril of the following year.

The project is expected to cost (U.S.) $2.8 bil-lion and will create 450 full-time jobs by the timeit is up and running in mid-2013.

Initial estimates suggest the Voisey’s Bay areacan be mined for up to 14 years, though somestudies have noted that the opportunity of har-vesting other materials could go on for decadesafter that.

The nickel-rich deposit was first discovered byprospectors in 1993. Property rights were acquiredby Vale three years later.

“We are very pleased with the progress thathas been made so far,” says Bob Carter, companyspokesperson in Newfoundland and Labrador.

Voisey’s Bay has already seen an integratedmine and concentrator, in operation since 2005,and a full-scale hydrometallurgical demonstrationplant built in Argentia in October of that year.

The construction of the processing facility inLong Harbour is the third and final phase of theproject.

“The total site is one kilometer by one kilo-meter in size, or about a million square feet,”Carter explains. “That’s about the size of 10 Wal-Mart stores side by side.

“Once all of the buildings have been claddedand enclosed then we will begin work on the in-ternal infrastructure,” he continues, “includingpiping, electricity, etc.”

The undertaking has been a boon to the areaeconomy, with a number of local and regionalfirms taking part in the process and an estimated2,200–2,500 new jobs being generated by theconstruction of the facility this year alone.

Concrete work for the project is being handledby Capital Ready Mix of St. John’s.

“Wewere awarded the contract in early 2010,”says company General Manager Jason Coish.

“Along with the fivemanagers, we’ve got abouta dozen full-time guys on site already,” he says.“However I expect that wewill need to bring a fewmore folks on board, mostly truck drivers I sus-pect, as things pick up over the coming months.”

Despite the challenges brought on by theoften-unpredictable weather conditions, Coishnotes that, so far, the process has been uneventful.“We mobilized and winterized the two batchplants quickly and without any issues. And thecompany has increased its safety standards rightacross the board with better and more relevanttraining and newer equipment.”

The process of mixing, pumping and pouringthe concrete, he adds, has been fairly routine todate. “There have been no new technologies orspecialized methods of placement involved. It isreally just business as usual for us.

“That being said,” Coish smiles, “we have beenvery busy — non-stop actually. By the time thatthe job is done we will have supplied 120,000cubic meters of concrete over just 27 months.”

Concrete for Vale Processing FacilityBusiness as Usual for Capital ReadyMix

The first concrete pour for the new processing facility for Vale at Long Harbour in Newfoundland took place in March 2010. Capital Ready Mix of St. John’s is handling theconcrete work for the project. (Photo: Vale)

By STEPHEN PATRICK CLARE

VOL. 20 • NO. 1

2 SPRING 2011 | ACA’s READY MIX NEWS

When surface aggregates become dis-lodged to the extent that the surface pro-file is no longer within specifications

resulting in large areas of loose aggregate particles,this is known as raveling. Whereas severe ravel-ing is unacceptable, some loose aggregate on a fin-ished pavement should always be expected andshould not be considered a pavement failure.The reasons for pervious concrete ravel-ling in our climate include:• The compaction was not adequate, especially

at edges and joints• Recent studies in Ontario have determined

that for surfaces that will be regularly ploughedit is best not to joint the pervious concrete.Pervious concrete does not crack linearly likenormal concrete as it hardens. It cracks in amore random fashion in 3 dimensions becauseof the voids. These tiny cracks are not un-

sightly and are much less likely to be caughtby the blade of a snow plough.

• The mixture during placement was not at theproper consistency – generally too dry and willshow a chalky or dusty appearance.

• The curing was not done properly. In coldweather pervious concrete is more susceptibleto freezing because its porous nature preventsit from generating and retaining heat of hydra-tion. Any freezing of the surface will likely re-sult in raveling. Precautions in cold weathershould be in place when the forecast indicatesthat the average daily temperature will be lessthan 4 degrees C during placement and/or thefirst 7 days of curing. Construction shouldnot be scheduled when there is a chance forliquid precipitation or when a cold front withfreezing temperatures is expected.

Troubleshooting PerviousConcrete - Raveling

We are very pleased to announce that theAtlantic Region now has 12 certifiedPervious Concrete Contractors. They

are: Eric Bender, Eric DeMos and Tanya Owensof Lafarge Canada; Johnathan Ferguson fromOcean Contractors; OSCO’s Ken O’Donnell;AllanMacQuarrie fromPrecisionConcrete;GeoffMacLean of Servant Dunbrack McKenzie Mac-Donald; JohnParnell fromSouth ShoreReadyMixLtd.; Donald Burden of Stantec Consulting, and

Adam McLeod, Brian Sanford and David Pem-berton from the Municipal Group of Companies.

These daring dozen sat for the NRMCA Per-vious Concrete Contractor Certification courseand examApril 12th hosted byACA at Inn on theLake. We were fortunate to have the expertise ofBart Kanters from the Ready Mix Concrete Asso-ciation ofOntario as instructor and examiner. Con-gratulations to all.

Pervious Certification Penetrates Atlantic Region

Those attending ACA’s first Pervious Contractor Certification course included: (Front row) TanyaOwens, Eric Ben-der and Eric DeMos. (Back row) John Parnell, Allan MacQuarrie and Johnathan Ferguson.

A pervious concrete demonstration project at the NSCC Waterfront Campus Centre for the Built Environment inDartmouth, Nova Scotia. (Photo: Quality Concrete)

ACA’s Dalhousie Commerce Co-op Student Rachel Ritacco demonstrates the wonders of Pervious Concrete at theReal Home Show at the Halifax Forum Friday March 4, 2011.

3ACA’s READY MIX NEWS | SPRING 2011

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In Ontario, concrete pavement is becoming a preferredchoice for decision makers when it comes to road con-struction projects.“We’re finding more and more people are picking up on

the advantages of concrete over asphalt pavement,” said SherrySullivan, MASc, P.Eng, LEED AP, and a Concrete Engineerwith the Ready Mixed Concrete Association of Ontario(RMCAO).

“TheMinistry of Transportation inOntario has started call-ing for alternate bids on road construction projects and thelast nine alternate bids were awarded in concrete,” said Sulli-van.

“We’re starting to find municipal units are also exploringtheir options when it comes to road construction,” she said.“People will bid on both concrete and asphalt” resulting in“municipalities getting better offers and “a better deal for thetaxpayer’s money.”

One tool that is helping promote the advantages of con-crete pavement is the website CANPav™.

“There’s no other tool of its kind,” said Sullivan. “The web-site was designed for Canada but is actually being used inter-nationally.”

Developed by the CementAssociation of Canada and theRMCAO, CANPav™ “is a free, safe, secure website whereusers can quickly determine the cost advantages of using con-crete as the paving material for municipal streets and roadsand commercial parking lots.”

Users have control over data input. The program gener-ates a cost comparison for the project in both concrete and as-phalt. (www.canpav.com/index.php/pages/info)

With costs for asphalt rising and falling with oil prices,concrete paving is even more financially beneficial on a first

cost basis in addition to the life cycle costs, said Sullivan.In a 50-year life cycle analysis, the designer period equals

25 years for both asphalt and concrete, she explained. “That’show long you should get out of a road before maintenance isrequired.

“After that maintenance needs to be done to keep it for25 more years. Typically asphalt freeways will be milled andpaved three or four times in that period. For concrete it’s amatter of sealing the joints, a more minor type of rehabilita-tion.”

Sullivan also noted concrete is more environmentallyfriendly than asphalt. Its eco certified production uses indus-trial byproducts in the manufacturing process that would oth-erwise have been sent to the landfill.

Consider Concrete – price anddurability make it increasinglyattractive for roadsBy KATHY JOHNSON

Concrete pavement is becoming a preferred choice in Ontario as seen in this photo of Highway 410. (Photo: Courtesy of the ReadyMixed Concrete Association of Ontario)

160

150

140

130

120

110

100

90

80

70

60

Source: Bureau of Labor Statistics: Producer Price Index, Asphalt Paving Mixtures & Blocks, Ready Mix Concrete

Relative Asphalt/Concrete PPI

1997

1998

1999 20

002001 20

022003

2004

2005

2006

2007

2008

2009

2010

2011

4 SPRING 2011 | ACA’s READY MIX NEWS

The provincial Department of Transportationand Infrastructure Renewal is planning ongetting into the road building business in

Nova Scotia. Their intention is to begin a chipsealing operation this year and add paving opera-tions next year.

They will take a total of $18million in 2012 tofund their operations. These funds would nor-mally go to the private sector. In addition, they willbe spending something in the range of $6 millionof taxpayers’ funds in acquiring assets such as chipseal equipment and an asphalt plant. They will notcompete for the work they take; it will be unten-dered. Based on 2010 provincial tender numbers,the $18M would make them the second largestroad building operation in NS.

The Nova Scotia Road Builders Association(NSRBA), which represents the majority of pri-vate sector road building businesses in theprovince, has strongly objected to this direction bythe Government. Analysis of their business planshas shown that theDepartment will not be able toprovide these services as cost effectively as the pri-

vate sector.As stated in the Government’s business plans,

no consultation took place with industry. TheGovernment has stated it will not be conductingan audit of these activities for up to 5 years, i.e.they will spend approximately $100 million of tax-payers’ money without checking to see if any valuewas derived for the taxpayer.

Past government intrusions into the privatesector have proven very expensive to the NovaScotia taxpayer. Government has no businessbeing in business.

Support for the NSRBA’s position has beenwidespread including: Construction AssociationofNS; TruckingAssociation ofNS;Canadian Tax-payers Foundation; Canadian Federation of Inde-pendent Business; Chamber of Commerce;MiningAssociation ofNS and theCanadianCon-structionAssociation. In addition, both oppositionparties have strongly objected to this direction.

The message to business in NS relative tomaking new investments in equipment and peo-ple is a very negative one based on the uncertaintythat this direction causes.

Province Competingwith Road BuildersBy GRANT FELTMATE, ED of NSRBA

Events & Dates to Remember:• ACA 16th Annual Golf Tournament – Amherst, NS – June 2nd & 3rd, 2011• ACA Summer Meeting & Family Fun Weekend – Concrete by the Sea – Fair-mont Algonquin, St. Andrews-by-the-Sea, NB - August 12th – 14th, 2011

• ACA Fall Board & Committee Meetings– October 17th, 2011• ACA/CAC Decementfest Concrete Mixer – December 12th, 2011• ACA and ACI’s joint AGM and Conference; ConAtlantic ‘12– Delta Fredericton– February 23rd – 25th, 2012

Despite the remnants of snow still scat-tered across northern New Brunswick in earlyMay, the infrastructure improvement projectat the Port of Belledune will be finished aheadof schedule.

Originally slated for completion this Oc-tober, the nearly two-year-old project is nowexpected to be done as early as July.

Funding for the initiative, which includesthe building of an 18-hectare cargo storagearea, a Roll-on-Roll-off (RO-RO) Barge Ter-minal and refurbishing of Terminal 1, was an-nounced in June of 2009. The federalgovernment contributed $26.4 million towardthe upgrades, while another $20.4 millioncame from the provincial Northern NewBrunswick Infrastructure Initiative.

“The total budget was estimated at $65.6million,” says Tracey Eddy of the Port of Belle-dune. “However, we are now forecasting tocome in under that number.”

He adds that the improvements will dou-ble the facility’s capacity.

“It makes us more competitive with thePort of Saint John and opens the doors for fu-ture opportunities with the Arctic Gatewayinitiative.”

In all, the venture has created more than175 jobs, bringing millions of dollars into theregion’s economy.

“Aside from management, most of theworkers, including the sub-contractors, arelocal and area residents,” says project managerStephen Ouellette of Halifax-based McNallyConstruction.

Ouellette notes that, so far, the project has

gone off without a hitch. “It’s been verysmooth. The only things that we have had todeal with have been the unpredictability ofthe weather conditions and some issues to dowith the slip-form concrete.”

Concrete work for the project is beinghandled by the Blanchard Group of nearbyDunlop, NB.

“We were hired on last summer,” explainsRené Blanchard, the company’s vice-presi-dent. “We had worked with McNally previ-ously, so we were familiar with one another.”

The two firms collaborated to develop aunique “ternary” blend of concrete to meetthe job specifications.

“There were some challenges to meet therequirements of the slip-form molds,” Blan-chard says, “but once we found the right mixdesign everything went according to plan.”

At the peak of the work the company hadbetween 5-8 employees on site.

“There were a total of 14 cribs, and eachcrib took 2-3 days of consecutive, around-the-clock pouring. Once those were completed wefinished up with the cope walls and keys.”

In all, over 20,000 cubic metric meters ofconcrete was poured and placed.

“It was a big project for us to be sure,”notes Blanchard. “But we are pleased with theresults, and I think that everyone involvedwith the construction is happy to see it fin-ishing ahead of schedule.

“In a smaller place like Belledune, a proj-ect of this size can have a huge impact on theentire community. These upgrades are sure tobring a lot more money and opportunity to thearea.”

Port of Belledune projectwill finish ahead of scheduleBy STEPHEN PATRICK CLARE

The concrete work at the Port of Belledune in northern New Brunswick took 2-3 days of consecutive, around-the-clock pouring. (Photo: The Blanchard Group)

21WilliamsAvenue • Dartmouth • NS • B3B 1X3 • 450-50701-877-554-4667 • www.credifax.com

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5ACA’s READY MIX NEWS | SPRING 2011

SAFETY AWARDSThe Atlantic Concrete Association was

proud to publicly recognize the excellentefforts of several Ready Mix Concreteproducers who promoted safe work-places with our annual Safety Awards.The Safety Award for producers of lessthan 6000 cubic meters of concrete waspresented to Barker’s Construction Lim-ited. Barker’s Construction had no WCBcompensable injuries during the over4800 hours worked in 2010.The SafetyAward for producers of between 6000and 25,000 cubic meters of concretewent to Ideal Concrete (2006) Ltd. thathad no compensable accidents reportedto the WCB out of 53941 total hoursworked. The Safety Award for producersof over 25,000 cubic meters of concretewent to Lafarge Canada Inc. operationsin New Brunswick andNova Scotia. Theyhad 2 compensable accidents to report

to WCB this year and their employeesworked a total of 133,139 hours.ACA is also very proud and happy to

recognize individual member plantswith no lost time accidents in 2010.

They are:• Barker’s Construction Limited,Baie Verte, Newfoundlandand Labrador

• Cabot Ready Mix Ltd., StationManuels, CBS, Newfoundlandand Labrador

• Ideal Concrete, Point Tupper, NovaScotia

• Ideal Concrete, Whycocomagh, NovaScotia

• Lafarge Canada, Fredericton,New Brunswick

• Lafarge Canada, Miramichi,New Brunswick

• Lafarge Canada, Moncton,New Brunswick

• Lafarge Canada, Oromocto,New Brunswick

• Lafarge Canada, Saint John,New Brunswick

• Lafarge Canada, Springhill,Nova Scotia

• Lafarge Canada, Sussex,New Brunswick

• Lafarge Canada, Truro, Nova Scotia• Lafarge Canada, Yarmouth,Nova Scotia

• Lamèque Ready-Mix, Lamèque,New Brunswick

• Ocean Contractors, Halifax,Nova Scotia

• Valley Concrete, Quispamsis,New Brunswick

New ACA President Doug Murrin from MurrinCoand ACA’s Safety Chair Paul Miller of Warren ReadyMix presents Lane Stewart of Lamèque Ready Mix aSafety Certificate in recognition of achieving no losttime accidents in 2010.

The remains of at least 11 concrete boompumps lie rusting in graveyards in the Ukrainealong with helicopters, trucks, cranes and otherradioactive equipment.

A power surge on April 26, 1986 overheatedreactor No. 4 at the Chernobyl nuclear powerplant and its 1,000-tonne reactor lid was cata-pulted meters in the air.

To contain the radiation, a number of man-ufacturers sent pump trucks—some with leadencased cabs—to take part in constructing themulti-tonne concrete and steel sarcophagus thatcovers reactor No. 4 in Chernobyl. It took over400,000m3 of concrete and between six and

seven months to complete the structure.Twenty-five years later decisions are being

made about whether to encase four reactorsat the Fukushima Daiichi nuclear power plantin concrete.

A 9.0 earthquake and the ensuing tsunamiwith 46-foot high waves rocked Japan March11 knocking out the cooling systems that cir-culate water in the reactor cores.

Within days a number of concrete boompump trucks joined helicopters pouring waterinto the crippled reactors trying to cool thecores.

The world’s largest concrete boom pump,the 80-tonne Putzmeister M70-5, wasshipped to Japan in April. The M70-5 has avertical reach of more than 227 feet, a hori-

zontal reach of almost 213 feet, and a five-sec-tion Z-fold boom. Its pump output is up to210 cubic yards per hour.

Mike Parigini, who helped design theM70-5, says it took a million yards of concreteto encase reactor No. 4 in Chernobyl. The en-gineer told the Sacramento Bee it would takemillions of (cubic) yards of concrete to seal offthe four damaged reactors in Fukushima.

Should Japanese officials elect to encasethe reactors a boom pump has the ability todeposit concrete precisely with its remotecontrolled articulating robotic arm that canoperate from over a kilometre from the site.

There are conflicting opinions about whatshould be done in Fukushima. Some engi-neers and nuclear physicists believe the reac-

tors should be encased in boron sand concreteand left until the radioactive materials decay.

But American independent nuclear con-sultant Jack DeVine and others believe anearthquake or tsunami could hit the countrycausing untold damage to the containmentstructures.

Last month the European Commission allo-cated an additional 110 million euros towardthe construction of a 20,000 tonne concrete andsteel dome being erected beside the Chernobylsarcophagus. Engineers plan to use rails to slidethe 100-metre high structure over the sarcoph-agus sealing it for 100 years.

The dome was supposed to be finished in2007 but with the lack of financial support thecompletion date is now 2015.

Concrete an important weapon in recent and historic Nuclear CrisesBy HEATHER JONES

Quality ConcreteAnnouncements

Quality Concrete wishes to recognize Mr. Daryl Cailon his retirement as President. A part of theconcrete industry for nearly forty years, and with theStevens Group for over 25 years, Mr. Cail played akey role in making Quality Concrete AtlanticCanada’s largest ready-mix producer. Known for hisquick wit and affable nature, Daryl looks forward tospending time with his wife Brenda and theirgrandsons Darien and P.J. While scaling back on hiswork routine, Mr. Cail will still remain with theStevens Group in the role of Business Development.

Quality Concrete would also like to congratulate Mr.Melvin Fiander on his appointment to the position ofPresident. Mr. Fiander has been with Quality Con-crete and active in the concrete industry since1985, having served as President of the Atlantic andCanadian concrete associations. In his most recentrole as Vice President of Operations, Mr. Fiander hasseen Quality Concrete grow from Dartmouth ReadyMix to Quality Concrete Limited. Presently operating11 production locations in Nova Scotia and NewBrunswick, Quality Concrete will continue to pro-mote advancements in the industry and offer strongtechnical support and customer service.

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w w w . b i r d s t a i r s . c aPlease contact Bird Stairs for all your construction needs,

we have six convenient locations to serve you better.FrederictonSaint John

MonctonDartmouth

HalifaxSaint John’s

Question A ----Are vapour retarders the 6mil polyethylene that we commonly referto as moisture barriers?

VAPOUR RETARDERS: For years vapour re-tarders have been mistakenly called vapour barri-ers or moisture barriers. There is a standard fortesting vapour transmission of materials that is

ASTM E96 –Standard Test Methods forWater Vapour Transmission of Materials. Vapourretarders are generally required to have a perme-ance of less than 0.3 perms as determined byASTM E96. Vapour barriers, made of multi-lay-ered composite materials, tested by ASTM E96often have permeance levels of 0.001 or below.

Vapour retarders should meet the minimumrequirements ofASTM E1745- Standard Specifi-cation for Water Vapour Retarders Used in Con-tact with Soil or Granular Fill Under ConcreteSlabs.

Conventional 6, 8, and 10-mil low-densitypolyethylene do not meet all requirements of theASTM E1745 Standard and are not recom-mended for use as below-slabmoisture protection.

The ACI Guide for Concrete Floor and SlabConstruction (302.1R) recommends a minimumvapour retarder thickness of 10-mil, and some re-cent studies have shown that even that thicknessmay be not sufficient to resist construction typedamage.

New generation materials (i.e. polyolefinvapour retarders) ASTM E1745 compliant, arenow being used and reported to be better resistant

to construction type conditions.Question B ---- Is it recommended that the6-mil polyethylene moisture barrier be 75mm or 100 mm below the slab and havecompacted fill above it?

Vapour retarders placed directly under con-crete slabs may increase the time delay beforefinal finishing due to longer bleeding times, par-ticularly in cold weather as all the bleed watermustmigrate through the thickness of the slab be-fore finishing. In the 1980s and 1990s, ACI 302recommended a 75 mm blotter layer of aggregatebetween the slab and vapour retarder to minimizethis effect. The idea was that some of the waterin the mix would go downward into the blottercourse and some swould rise to the top and thuscut down the delay time before finishing and thusspeed up construction.

However, ACI Committee 302’s, Guide forFloor and Slab Construction currently does notrecommend a cushion /blotter layer for concretefloors that are to receive adhered floor coverings orlow-permeability coatings. Environmental con-cerns have changed the flooring industry. Many ofthe new floor coverings and their adhesives reactwith moisture and particularly to combinations ofmoisture and alkalis that come from concrete. Ifconcrete is placed on a saturated blotter layer overa vapour retarder, the drying time for the concreteslab can increase extraordinarily; this is becausethe extra water can only be removed by diffusionupward through the entire slab. In 2001,ACI 302issued a cautionary note regarding the location ofa vapour retarder. The note also contains a flowchart that represents a series of questions to con-

sider when assessing whether or not a vapour re-tarder should be used. The decision should bemade on a job-to-job basis.

References and Related PublicationsACI, Committee 302, Guide for Con-

crete Floor and Slab Construction, ACI302.1R, American Concrete Institute,Framington Hills, Michigan, USA.

Tarr, Scott M., and Farney, James A., ConcreteFloors on Ground, Fourth Edition, EB 075.04,Portland Cement Association, Skokie, Illinois,USA..

Kanare, HowardM., Concrete Floors andMois-

ture, EB119, PortlandCementAssociation, Skokie,Illinois, USA, andNational ReadyMixed ConcreteAssociation, Silver Spring, Maryland, USA.

(N. F. (Norm) MacLeod, P. Eng. is one of theauthors of the CementAssociation of Canada’s pub-lication, Design and Control of Concrete Mixtures.He has received several awards recognizing his manyyears of valuable service to the industry including theDistinguished ServiceAward from the Portland Ce-mentAssociation. He is anHonourary LifeMemberof the Atlantic Concrete Association, and a LifeMember of theAssociation of Professional Engineersof Nova Scotia.)

Ask The Expert

As summer approaches it’s time to startthinking about “hot weather concreting”. Aquick review of ACI 305 Hot Weather Con-creting or Chapter 13 in the Cement Associa-tion of Canada’s Design and Control ofConcrete Mixtures would be a good thing todo. Everything from curing, site preparation tochanges in mix designs should be consideredbefore the air temperature and delivered con-crete temperatures spike. Concrete is an idealbuilding material in a sustainable future andthere is an ever-increasing demand for exposedslabs on grade, exposed aggregate concrete,decorative/stamped concrete, integral colouredconcrete, and the utilization of micro/macro fi-bres in the mix. Furthermore, changes toCanada’s VOC laws in 2009 have affected theformula for curing agents. Expectations for apremium, long lasting finished product arehigher than ever, and so careful attention tomix design, placement, finishing and curing

should be observed.During hot weather, freshly mixed concrete

is in danger of becoming compromised be-cause high temperatures and low relative hu-midity result in accelerated moisture loss andspeed up cement hydration. Wind speed andsolar radiation also contribute to the difficultyof pouring and placing concrete under theseconditions.

Some procedures, supplementary cement-ing materials and admixtures can be used tohelp reduce the effects of hot weather on freshconcrete. Aggregates can be dampened andshaded to reduce temperature before batchingbegins. Water supply lines and tanks can beshaded or buried away from direct sunlight.Using mixer drums of a lighter colour will alsohelp to reduce concrete temperature. Finish-ing tools can be dampened for cooling. Pre-dampening and shading the sub-grade (usingwalls and a roof if possible) and erecting windbarriers are also important mitigation strate-gies.

Admixtures can also help in hot weatherconcreting. They will not solve all the issues

but can be an integral part of the solution toproduce a durable and functional concretemix. Set retarding admixtures will help to cre-ate normal setting times for concrete travellinglong distances at higher temperatures. Theseare available in water reducing/retarding ad-mixtures as well as set retarding or hydrationcontrol only admixtures. Caution must still betaken once placement begins because windand solar radiation will have the same in-creased effect on the fresh concrete.

The addition of water (in the ready mixtruck or during placement/finishing) at thejobsite will greatly affect the properties andserviceability of the hardened concrete. Mid-range water reducers usually don’t help in thecooling of fresh concrete but will help in con-trolling bleed water and will increase the de-signed slump of the ready mixed concretewithout the addition of added water. Thesebenefits help counter the rapid evaporationand slump loss due to high concrete tempera-tures and moisture loss. This can help in in-creased workability and a more desiredfinishability for the placers and finishers.

High-range water reducers (superplasticiz-ers) will generally act in the same manner asmid-range water reducers for flatwork butallow for a higher slump range. However, cau-tion should be taken when using polycarboxy-late superplasticizers with and without airentrainment as they can produce an undesiredincrease in the percentage of air. In-housetests/discussions with your admixture suppliershould show the producer how mixing times,mixing speeds, air-entraining agent dosagesand other ingredients will react (if at all) afterthe addition of a superplasticizer. Other spe-cialty admixtures, such as shrinkage reducingadmixtures, shrinkage compensating admix-tures and air reduction admixtures, are avail-able to help in providing a desired and durableconcrete.

Contact your local admixture representa-tive, cement provider or testing consultant forfurther information on admixtures, cementand best practices for hot weather concreting.

(Steven Peters is the Atlantic Canada Tech-nical Representative for Euclid AdmixturesCanada.)

Hot Weather, Flatwork, and AdmixturesBy STEVEN PETERS

By NORMAN MACLEOD, P.ENG.

Norman MacLeod (left) discusses concrete issues with Mike Lio of Lafarge Canada at ACA’s annual Decementfestcelebration.

7ACA’s READY MIX NEWS | SPRING 2011

ACA traditionally rotates its annual generalmeeting among the four Atlantic Provinces everyyear. The fifth year, however, is a time to take ourAGM offshore. This year we headed to the Ex-cellence Playa Mujeres Hotel in Mexico. Happily,we achieved a quorum of numbers present and byproxy were able to conduct business that includedsetting the budget, making a change to our bylawsand changing our slate of officers. Mark MunroandDave andWanda Black were key organizers of

the weeklong event. Highlights included ourAGM, an exotic dinner on the beach, a reception,cruise and special entertainment on a large cata-maran as the sun went down and the moon rose.Many of us also took the time for shopping ex-cursions into Cancun, sightseeing trips to Mayanruins and/or adventure tours such as swimming incenotes, ziplining and rappelling. Check out thepictures here for a taste of our time in the sun.

ACA Takes it to Mexico

ACA Board of Directors Group Shot after AGM inMexico.

Ken, Francis, Roland, Lane, Dave and Bob were all finalists in the Atlantic Dance-Off.The ACA group poses in the foyer of the Excellence Playa Mujeres.

Paul and Sylvie brought a little bit of Ireland toMexico.Michelle and David enjoy one of the many gourmetrestaurants at the resort.

Mayan tour of Chichen Itza.

P innac le Agenc ies L td .M a t e r i a l C o n s u l t a n t s t o C o n s t r u c t i o n & I n d u s t r y

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8 SPRING 2011 | ACA’s READY MIX NEWS

2011 delivered a first quarter of firsts forACA’s ConcreteDelivery Professional (CDP) pro-gram. For the first time we certified over100CDPs (156 in total), delivering eight separatetraining sessions (four was the previous record),taking the course to Labrador City, NL, as well asBathurst NB where it was delivered in French(Opérateurs de Bétonnières (OBP’s).

The courses were delivered by an excellentline-up of instructors. They included: Karl Ben-nett of DisabiltiyManagementConsultants;MarkButt of OSCO; Sylvain Comeau of Roy Consult-ants; Bill Dooley; Mel Fiander of Quality Con-crete; Stewart Franck of Riskcheck Inc; StephenGrainger of Stantec Consulting; Yvette Hughes ofAMEC; Serge Kerry of SK Management; BrianHimmelman of South Shore Ready Mix; GordonLeaman of Stantec Consultants; Mary MacaulayofACA; KenMarginson of LafargeCanada; KevinNickerson of Quality Concrete, and Mark Wood-worth of OSCO.

Thanks also go to our Producer members whochose to send their employees to this valuabletraining programwhich covers 5modules in Prod-uct Knowledge; Environment; Customer andCompany Relations; Safety; and Vehicle Mainte-nance and Operations. Participating Producermembers included: Bèton Brunswick; Bridgewa-ter ReadyMix; Capital ReadyMix; Chaleur ReadyMix; Concrete Products; Groupe Blanchard; H &H Enterprises; Ideal Concrete; Lafarge Canada;Lamèque ReadyMix;MurrinCoReadyMix; NewConcrete; OSCO; Peninsula Ready Mix; QualityConcrete; South Shore Ready Mix; St. IsidoreReady Mix; Strescon; Timothy Cook Construc-tion; Valley Concrete, and Warren Ready Mix.

As always participants gaveACA excellent re-views and feedback about this important programdesigned to increase the quality and safety of ourready mix product and service.

CDP breaks new groundin Atlantic Canada We are very happy to announce that the

ACI Flatwork Finisher and Technician courseand exam held April 12th at Inn on the Lakewas well attended by the Industry across At-lantic Canada and beyond.

The following companies now have ACICertified Flatwork Technicians: Clyde RiverConstruction, Cornwall, PE; Concreate USL,Bolton, ON; Defence Construction Canada,Halifax, NS; Dexter Construction - ValleyDiv., Wolfville, NS; Ivanov Concrete Finish-ing, Dieppe, NB; Lafarge Concrete, Moncton,NB; Ocean Contractors, Halifax, NS; OSCO,Charlottetown, PE; Power Concrete Finish-ing, Charlottetown, PE; Stantec Consulting,Corner Brook, NL; T&E Heighton Construc-tion, River John, NS, and The MunicipalGroup of Companies, Bedford, NS.

Certification is valid for five years and isawarded to individuals. This course was heldby ACA in partnership with the ACI AtlanticChapter and taught by Bart Kanters from theReady Mix Concrete Association of Ontario.

Looking for Contractors with CertifiedFlatworkers? Have we got a list for you!

Bart Kanters, P.Eng. from RMCAO presented the ACIFlatwork Finisher/TechnicianCertificationCourse at theInn on the Lake in April.

Opérateurs de Bétonnières doing their vehicle pre-trip inspection in Bathurst, New Brunswick.

ACA’s first CDP class in Labrador doing their pre-trip inspection in Labrador City, NL.

IdealConcrete’s Point Tupper,Nova Sco-tia plant is using the Blue Maxx InsulatedConcrete Form System. Its insulating capac-ity combinedwith reinforced concretemakesit stronger, safer, quieter, and more energy ef-ficient. The plant is comfortably heated withonly three small electric baseboard heaters.

Another energy saving and pollution re-ducing innovation at Ideal is the introduction

of “threeminute automatic shutdown” in10ofits 19 concrete trucks. Ideal continues to re-cycle left over concrete into various forms andapplications.

Finally employees recycle plastic and glassand donate it to a non-profit organization thatbenefits mentally challenged people.

ACA presented Ideal Concrete with a2010 EnvironmentAward.

Ideal Concrete raisesthe environmental bar

V.J. Rice continued tomake significant envi-ronmental strides in 2010. Environmental TeamLeader Bryan Rice reported that new machineattachments are nowused to remove snowmoreefficiently.A new water truck was purchased fordust control so that the use of calcium chloridecould be eliminated. Environmentally friendlyacid is now being used to clean concrete buildup on the trucks and a vacuum trailer was ac-quired so spills could be quickly mopped up.

He said V.J. Rice also purchased more con-crete forms to reclaim waste concrete and the

company is also recycling used tires. Energy sys-temswithin the plantswere updatedwith an ex-pansion of its wood heating system that hasreplaced oil in two buildings.Ash from thewoodfurnaces is used as fertilizer.

Finally, the Bridgetown, Nova Scotia plantnow has a primary electrical metering system tohelp cut down on electrical use and costs, buy-ing electricity during off peak demand.

ACA presented V.J. Rice with a 2010 Envi-ronmentAward.

V.J. Rice — a lean green machine

Atlantic Chapteramerican concrete institute

President Corey BolandTel: (506) 459-8106 email: cboland@cityconcreteltd.ca

Secretary Rob SimpsonTel: (506) 453-3939 • Email: robert.simpson@gnb.ca

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The objectives of the American Conrete Institute are to further education and technical practice, scientificinvestigation and research on a non-profit basis through publications, seminars, lectures and workshops.Members have access to an extensive library of publications and ACI videos, information and reducedcosts for local technical seminars and ACI certification courses. Stay informed by becoming a member!