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Planning and Planning and Placing Concrete Placing Concrete

Planning and Placing Concrete Planning and Placing Concrete

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Page 1: Planning and Placing Concrete Planning and Placing Concrete

Planning and Placing Planning and Placing ConcreteConcrete

Page 2: Planning and Placing Concrete Planning and Placing Concrete

Next Generation Science/Common Core Standards Addressed!Next Generation Science/Common Core Standards Addressed!

CCSS.ELA Literacy. RST.9‐10.3 Follow precisely a complex multistep CCSS.ELA Literacy. RST.9‐10.3 Follow precisely a complex multistep procedure when carrying out experiments, taking measurements, or procedure when carrying out experiments, taking measurements, or performing technical tasks, attending to special cases or exceptions performing technical tasks, attending to special cases or exceptions defined in the text.defined in the text.

CCSS.ELA Literacy. RST.9‐ 10.5Analyze the structure of the relationships CCSS.ELA Literacy. RST.9‐ 10.5Analyze the structure of the relationships among concepts in a text, including relationships among key terms (e.g., among concepts in a text, including relationships among key terms (e.g., force, friction, reaction force, energy).force, friction, reaction force, energy).

CCSS.ELA Literacy. RST.11‐ 12.3 Follow precisely a complex multistep CCSS.ELA Literacy. RST.11‐ 12.3 Follow precisely a complex multistep procedure when carrying out experiments, taking measurements, or procedure when carrying out experiments, taking measurements, or performing technical tasks; analyze the specific results based on performing technical tasks; analyze the specific results based on explanations in the textexplanations in the text

CCSS.ELA Literacy. RST.11‐12.4 Determine the meaning of symbols, key CCSS.ELA Literacy. RST.11‐12.4 Determine the meaning of symbols, key terms, and other domain‐specific words and phrases as they are used in a terms, and other domain‐specific words and phrases as they are used in a specific scientific or technical context relevant to grades 11–12 texts and specific scientific or technical context relevant to grades 11–12 texts and topics.topics.

CCSS.Math.Content.HSGCO.D.12 Make formal geometric constructions with CCSS.Math.Content.HSGCO.D.12 Make formal geometric constructions with a variety of tools and methods (compass and straight edge, string, a variety of tools and methods (compass and straight edge, string, reflective devices, paper folding, dynamic geometric software, etc.). reflective devices, paper folding, dynamic geometric software, etc.). Copying a segment; copying an angle; bisecting a segment; bisecting an Copying a segment; copying an angle; bisecting a segment; bisecting an angle; constructing perpendicular lines, including the perpendicular angle; constructing perpendicular lines, including the perpendicular bisector of a line segment; and constructing a line parallel to a given line bisector of a line segment; and constructing a line parallel to a given line through a point not on the linethrough a point not on the line

Page 3: Planning and Placing Concrete Planning and Placing Concrete

Bell Work / Student Learning ObjectivesBell Work / Student Learning Objectives

Describe how to plan the Describe how to plan the outlined job provided by your outlined job provided by your instructor.instructor.

Discuss preparation for the Discuss preparation for the concrete pour.concrete pour.

Explain placing, finishing, and Explain placing, finishing, and curing concrete.curing concrete.

Page 4: Planning and Placing Concrete Planning and Placing Concrete

Terminology Terminology Bag mixBag mix Broom finishBroom finish Bull floatBull float Calcium chlorideCalcium chloride Coarse aggregateCoarse aggregate ConcreteConcrete Concrete dragConcrete drag Concrete edgerConcrete edger Concrete formConcrete form Concrete jointerConcrete jointer CuringCuring

DarbyDarby Earthen formEarthen form Fine aggregateFine aggregate Float finishFloat finish FloatingFloating Form nailsForm nails Gallon mixGallon mix Magnesium or Magnesium or

wooden hand floatwooden hand float Portland cementPortland cement Power trowelPower trowel

Page 5: Planning and Placing Concrete Planning and Placing Concrete

Terminology Terminology

Reinforcing Reinforcing barsbars

Reinforcing wireReinforcing wire Steel hand Steel hand

concrete concrete finishing trowelfinishing trowel

Striking offStriking off Troweled finishTroweled finish

Page 6: Planning and Placing Concrete Planning and Placing Concrete

Anticipated Problem:Anticipated Problem:

What do you need to know What do you need to know before pouring concrete?before pouring concrete?

Page 7: Planning and Placing Concrete Planning and Placing Concrete

ConcreteConcrete

Is a mixture of coarse Is a mixture of coarse aggregate, fine aggregate, aggregate, fine aggregate, portland cement, and water.portland cement, and water.

Page 8: Planning and Placing Concrete Planning and Placing Concrete

ConcreteConcrete

Coarse aggregate: GravelCoarse aggregate: Gravel Fine aggregate: Coarse sandFine aggregate: Coarse sand Portland cement: Cement made Portland cement: Cement made

from burning lime, silica, iron from burning lime, silica, iron oxide, and alumina together. oxide, and alumina together. Gypsum is then added, which acts Gypsum is then added, which acts

as a glue that holds everything as a glue that holds everything togethertogether

Page 9: Planning and Placing Concrete Planning and Placing Concrete

Cubic YardsCubic Yards Concrete is figured and sold by Concrete is figured and sold by

the cubic yardthe cubic yard Commonly drop the word “cubic” Commonly drop the word “cubic”

and refer to concrete by the yardand refer to concrete by the yard To calculate the amount needed To calculate the amount needed

convert the length, width, and convert the length, width, and thickness into feet, multiply them thickness into feet, multiply them together, and divide by 27 together, and divide by 27

One cubic yard is 27 cubic feet.One cubic yard is 27 cubic feet.

Page 10: Planning and Placing Concrete Planning and Placing Concrete

Cubic YardsCubic Yards

For example a concrete For example a concrete driveway 18 foot × 30 foot driveway 18 foot × 30 foot poured six inches thick would poured six inches thick would be 10 cubic yards (18 × 30 × .5 be 10 cubic yards (18 × 30 × .5 ÷ 27 = 10 cubic yards).÷ 27 = 10 cubic yards).

Page 11: Planning and Placing Concrete Planning and Placing Concrete

Selecting MaterialsSelecting Materials

Use quality materialsUse quality materials If soil is present in the sand or If soil is present in the sand or

gravel, the result will be weak gravel, the result will be weak concreteconcrete

Use clean “washed” sand Use clean “washed” sand

Page 12: Planning and Placing Concrete Planning and Placing Concrete

Mixing IngredientsMixing Ingredients

Mix in correct proportionsMix in correct proportions Driveways, walks, floors, and Driveways, walks, floors, and

watertight foundations should be watertight foundations should be a six gallon mixa six gallon mix

Foundation walls, footing, and Foundation walls, footing, and mass concrete can be a seven mass concrete can be a seven gallon mix.gallon mix.

Page 13: Planning and Placing Concrete Planning and Placing Concrete

Mixing IngredientsMixing Ingredients Gallon mix: Number of gallons of Gallon mix: Number of gallons of

water used with a bag of cement.water used with a bag of cement.

Less water means stronger concreteLess water means stronger concrete

Page 14: Planning and Placing Concrete Planning and Placing Concrete

Mixing IngredientsMixing Ingredients

Bag mix: Number of bags or sacks Bag mix: Number of bags or sacks of cement used per cubic yard of of cement used per cubic yard of concrete.concrete. Example: Six bag mix - Six bags of Example: Six bag mix - Six bags of

cement per cubic yardcement per cubic yard Correct proportions for a six bag mixCorrect proportions for a six bag mix

One part cement to 2¼ parts fine One part cement to 2¼ parts fine aggregate to 3 parts coarse aggregate to 3 parts coarse aggregate.aggregate.

Page 15: Planning and Placing Concrete Planning and Placing Concrete
Page 16: Planning and Placing Concrete Planning and Placing Concrete
Page 17: Planning and Placing Concrete Planning and Placing Concrete

PlanningPlanning

Purchase material to build Purchase material to build concrete forms concrete forms

Assembling tools needed forAssembling tools needed for Digging, Digging, Building and setting forms, Building and setting forms, Installing reinforcement, Installing reinforcement, Pouring concrete, andPouring concrete, and Finishing concreteFinishing concrete

Page 18: Planning and Placing Concrete Planning and Placing Concrete

Anticipated Problem:Anticipated Problem:

What do I need to do What do I need to do before the concrete before the concrete

arrives?arrives?

Page 19: Planning and Placing Concrete Planning and Placing Concrete

PreparationPreparation

Concrete may be mixed Concrete may be mixed In a wheelbarrow using a shovel In a wheelbarrow using a shovel

or or Shoveled into a small electric or Shoveled into a small electric or

gasoline powered mixergasoline powered mixer Most people purchase ready-Most people purchase ready-

mixed concrete from a local mixed concrete from a local supplier.supplier.

Page 20: Planning and Placing Concrete Planning and Placing Concrete

Digging Digging

In many cases the area where In many cases the area where concrete is to be poured or concrete is to be poured or placed must be dug out. placed must be dug out. Example: Driveways and sidewalks Example: Driveways and sidewalks

are generally one inch above the are generally one inch above the ground level when finished.ground level when finished.

Small areas: A shovel may be Small areas: A shovel may be usedused

Page 21: Planning and Placing Concrete Planning and Placing Concrete

DiggingDigging

Larger areas need a backhoe, Larger areas need a backhoe, grader blade, or loader bucket to grader blade, or loader bucket to speed up the jobspeed up the job

In some cases, like a floor, the In some cases, like a floor, the concrete should be level while in concrete should be level while in other situations, like a driveway, other situations, like a driveway, the concrete should slope away the concrete should slope away from the housefrom the house

Page 22: Planning and Placing Concrete Planning and Placing Concrete

FormsForms Concrete form: Frame or Concrete form: Frame or

mold that holds wet concrete mold that holds wet concrete in shape until it has set or in shape until it has set or hardened. hardened.

The forms must be strong The forms must be strong and rigid to prevent sagging, and rigid to prevent sagging, bulging, and spreadingbulging, and spreading

Page 23: Planning and Placing Concrete Planning and Placing Concrete

FormsForms Freshly poured concrete exerts Freshly poured concrete exerts

great pressuregreat pressure Earthen form: Trench dug in Earthen form: Trench dug in

the ground with solid walls the ground with solid walls Used for concrete footingUsed for concrete footing

Page 24: Planning and Placing Concrete Planning and Placing Concrete

Foundation Footing!Foundation Footing!

Page 25: Planning and Placing Concrete Planning and Placing Concrete

FormsForms When wooden forms are used When wooden forms are used

they must be tight to prevent they must be tight to prevent the escape of the water-the escape of the water-cement paste cement paste A tightly stretched nylon line is A tightly stretched nylon line is

useful to set the forms in a useful to set the forms in a straight line straight line Wooden stakes are used to hold Wooden stakes are used to hold the form boards in positionthe form boards in position

Page 26: Planning and Placing Concrete Planning and Placing Concrete

FormsForms

Small jobs: Four foot level on Small jobs: Four foot level on top of the form can be used to top of the form can be used to set the forms level or slopingset the forms level or sloping

Surveying level: Needed to set Surveying level: Needed to set larger jobs. larger jobs.

Page 27: Planning and Placing Concrete Planning and Placing Concrete

FormsForms Form nails (or scaffold nails): Form nails (or scaffold nails):

Double-headed nail used to Double-headed nail used to fasten the boards to the stakesfasten the boards to the stakes

Coating forms with used motor Coating forms with used motor oil or diesel fuel and using oil or diesel fuel and using form nails make form removal form nails make form removal much easiermuch easier

Page 28: Planning and Placing Concrete Planning and Placing Concrete

FillFill

Fill sand or rock should be Fill sand or rock should be added if the area is too deep.added if the area is too deep.

Drag board can be used as fill Drag board can be used as fill is added so that the is added so that the recommended thickness of recommended thickness of concrete will be pouredconcrete will be poured

Page 29: Planning and Placing Concrete Planning and Placing Concrete

FillFill

Fill, especially sand, should be Fill, especially sand, should be packed or tamped down so that it packed or tamped down so that it is solid.is solid.

Do not use soil as fill because it Do not use soil as fill because it will settle later leaving a void will settle later leaving a void or hole under the concrete or hole under the concrete which will allow slab movement.which will allow slab movement.

Page 30: Planning and Placing Concrete Planning and Placing Concrete

PlasticPlastic

Place sheet of plastic on top of Place sheet of plastic on top of the pour if the weather is very the pour if the weather is very warm and you would like to warm and you would like to slow down drying and curing slow down drying and curing timetime

Also concrete floors with plastic Also concrete floors with plastic under them are less likely to be under them are less likely to be damp.damp.

Page 31: Planning and Placing Concrete Planning and Placing Concrete

Reinforcing Bars and WireReinforcing Bars and Wire

If heavy equipment will drive over If heavy equipment will drive over concrete or freezing and thawing concrete or freezing and thawing will be a problem, concrete should will be a problem, concrete should be reinforcedbe reinforced

Reinforcing bars: Steel bars with Reinforcing bars: Steel bars with ridges that bond with the ridges that bond with the concreteconcrete Commonly seen in the construction Commonly seen in the construction

of highways and bridge decksof highways and bridge decks

Page 32: Planning and Placing Concrete Planning and Placing Concrete

Reinforcing Bars and WireReinforcing Bars and Wire Reinforcing wire: Rolls with wire Reinforcing wire: Rolls with wire

rectangles or squares rectangles or squares approximately 6 inches on approximately 6 inches on centercenter Used in lighter construction such Used in lighter construction such

as patios and sidewalks.as patios and sidewalks. Metal is used because it expands Metal is used because it expands

and contracts at the same rate and contracts at the same rate as hardened concreteas hardened concrete

Page 33: Planning and Placing Concrete Planning and Placing Concrete
Page 34: Planning and Placing Concrete Planning and Placing Concrete

Hot WeatherHot Weather

Consider spraying the area to Consider spraying the area to be poured with water when the be poured with water when the concrete arrivesconcrete arrives

Page 35: Planning and Placing Concrete Planning and Placing Concrete

Moisture ContentMoisture Content

Be sure there are no dry Be sure there are no dry clumps and the concrete is clumps and the concrete is thoroughly mixed whether you thoroughly mixed whether you mix or buy ready-mixed.mix or buy ready-mixed.

Water content is very importantWater content is very important

Page 36: Planning and Placing Concrete Planning and Placing Concrete

Moisture ContentMoisture Content Extra water will result in weak Extra water will result in weak

concrete but concrete that is concrete but concrete that is too dry is very difficult to pour too dry is very difficult to pour and level off. It may also leave and level off. It may also leave voids with exposed coarse voids with exposed coarse aggregate.aggregate.

Watch experienced concrete Watch experienced concrete finishers or hire one to help the finishers or hire one to help the first time you pour concrete.first time you pour concrete.

Page 37: Planning and Placing Concrete Planning and Placing Concrete

Fiberglass fibersFiberglass fibers

May be added to the concrete May be added to the concrete as it is mixed at the ready-mix as it is mixed at the ready-mix plant as a way to reinforce it.plant as a way to reinforce it.

Page 38: Planning and Placing Concrete Planning and Placing Concrete

Calcium ChlorideCalcium Chloride

If concrete is poured in cold If concrete is poured in cold weather calcium chloride is weather calcium chloride is added to prevent the concrete added to prevent the concrete from freezing as it curesfrom freezing as it cures

Building paper or straw can be Building paper or straw can be used to cover the concrete used to cover the concrete after it is finished and while it is after it is finished and while it is curingcuring

Page 39: Planning and Placing Concrete Planning and Placing Concrete

Anticipated Problem:Anticipated Problem:

How is concrete placed, How is concrete placed, finished, and cured?finished, and cured?

Page 40: Planning and Placing Concrete Planning and Placing Concrete

Placing and Finishing concretePlacing and Finishing concrete

Should not be attempted Should not be attempted without having plenty of laborwithout having plenty of labor

After concrete is mixed the After concrete is mixed the drying and curing process drying and curing process begins you are working against begins you are working against the clockthe clock

Be sure all placing and finishing Be sure all placing and finishing tools are on handtools are on hand

Page 41: Planning and Placing Concrete Planning and Placing Concrete

Moving and Spreading ConcreteMoving and Spreading Concrete

Common tools used to move Common tools used to move and spread material:and spread material: Shovels, Shovels, Spades,Spades, Rakes, and Rakes, and Concrete dragsConcrete drags Floats and trowels Floats and trowels

Page 42: Planning and Placing Concrete Planning and Placing Concrete

Moving and Spreading ConcreteMoving and Spreading Concrete

Since concrete is so heavy: Move Since concrete is so heavy: Move it downhill with a chuteit downhill with a chute Closer the concrete chute is to Closer the concrete chute is to

where the concrete is needed, the where the concrete is needed, the less work is requiredless work is required

Areas where the chute cannot Areas where the chute cannot reach: use wheelbarrowreach: use wheelbarrow

Concrete should be pushed, pulled, Concrete should be pushed, pulled, or lowered rather than liftedor lowered rather than lifted

Page 43: Planning and Placing Concrete Planning and Placing Concrete

Moving and Spreading ConcreteMoving and Spreading Concrete

Concrete drag: Solid blade with a Concrete drag: Solid blade with a handle used to push or drag concrete handle used to push or drag concrete into low spotsinto low spots

Striking off: Using a drag board that is Striking off: Using a drag board that is usually a 2 ×4 or a 2 ×6 that is used to usually a 2 ×4 or a 2 ×6 that is used to “saw” back and forth to level the “saw” back and forth to level the concrete. concrete.

Page 44: Planning and Placing Concrete Planning and Placing Concrete

Moving and Spreading ConcreteMoving and Spreading Concrete Work team for placing concrete:Work team for placing concrete:

One person needed at each end of One person needed at each end of the drag board the drag board

Third person with rubber boots and Third person with rubber boots and a concrete drag in middle of the a concrete drag in middle of the concrete make a good team for concrete make a good team for placing concreteplacing concrete

Other workers are needed to Other workers are needed to operate the wheelbarrows and operate the wheelbarrows and shovelsshovels

Page 45: Planning and Placing Concrete Planning and Placing Concrete

Moving and Spreading ConcreteMoving and Spreading Concrete

A drag board vibrator can be A drag board vibrator can be clamped to two drag boardsclamped to two drag boards One person with the drag board One person with the drag board

vibrator can do the same work as vibrator can do the same work as two people without it. two people without it.

The concrete should be The concrete should be dragged twice before going on dragged twice before going on to the next step.to the next step.

Page 46: Planning and Placing Concrete Planning and Placing Concrete
Page 47: Planning and Placing Concrete Planning and Placing Concrete

Moving Fine MaterialMoving Fine Material

To vibrate the fine material To vibrate the fine material next to the form board:next to the form board: Hammer: Used to tap the form Hammer: Used to tap the form

boardsboards Spade: Used to jab up and down Spade: Used to jab up and down

inside the form boardinside the form board

Page 48: Planning and Placing Concrete Planning and Placing Concrete

FloatingFloating Pushing the rocks down and Pushing the rocks down and

bringing sand-cement paste bringing sand-cement paste to the surface and beginning to the surface and beginning the smoothing processthe smoothing process

Magnesium or wooden hand Magnesium or wooden hand float: Used to smooth the float: Used to smooth the area near the edge of the area near the edge of the work areawork area

Use a semi-circular motion Use a semi-circular motion when using a hand float.when using a hand float.

Page 49: Planning and Placing Concrete Planning and Placing Concrete

FloatingFloating Darby: Two handed float Darby: Two handed float

usually 18” long that is also usually 18” long that is also used near the edgeused near the edge

Bull float: 36 or 42 inch float Bull float: 36 or 42 inch float with long round handle used to with long round handle used to reach areas away from the reach areas away from the edgeedge

Page 50: Planning and Placing Concrete Planning and Placing Concrete

Rounding the EdgeRounding the Edge

Concrete edger: Used to push Concrete edger: Used to push rocks down near the form rocks down near the form board to round the edge board to round the edge Prevents a chipping or breaking Prevents a chipping or breaking

when the form board is removedwhen the form board is removed

Page 51: Planning and Placing Concrete Planning and Placing Concrete

GroovingGrooving

Concrete jointer: Used to Concrete jointer: Used to put grooves across put grooves across concrete areas like concrete areas like sidewalkssidewalks

Joints help the Joints help the appearance and provide appearance and provide relief area for expansion relief area for expansion and contraction and contraction

Makes cracks in concrete Makes cracks in concrete less noticeableless noticeable

Page 52: Planning and Placing Concrete Planning and Placing Concrete

Finishing ConcreteFinishing Concrete

Float finish: Leaves rough finish Float finish: Leaves rough finish

acceptable for a livestock feeding acceptable for a livestock feeding floor or footingfloor or footing

Troweled finish: Very smooth Troweled finish: Very smooth finish finish Used home, business and garage Used home, business and garage

floorsfloors

Page 53: Planning and Placing Concrete Planning and Placing Concrete

Finishing ConcreteFinishing Concrete

Steel hand concrete finishing Steel hand concrete finishing trowel: Used for small jobs and trowel: Used for small jobs and near the edge on large jobs. near the edge on large jobs.

Use in a semi-circular motion Use in a semi-circular motion much like floating exceptmuch like floating except

greater pressure is greater pressure is

needed.needed.

Page 54: Planning and Placing Concrete Planning and Placing Concrete

Finishing ConcreteFinishing Concrete

Power trowel: Gasoline Power trowel: Gasoline powered trowel with three or powered trowel with three or four blades four blades Used to finish large areasUsed to finish large areas

Page 55: Planning and Placing Concrete Planning and Placing Concrete

Finishing ConcreteFinishing Concrete

Broom finish: Made by using a Broom finish: Made by using a coarse bristle concrete broom coarse bristle concrete broom or floor broom either after or floor broom either after floating or after trowelingfloating or after troweling Often used on driveways and Often used on driveways and

sidewalks for added tractionsidewalks for added traction

Page 56: Planning and Placing Concrete Planning and Placing Concrete

CuringCuring

Process of concrete drying and Process of concrete drying and hardening.hardening.

Slower the moisture leaves, the Slower the moisture leaves, the stronger the concrete will stronger the concrete will become. become.

Page 57: Planning and Placing Concrete Planning and Placing Concrete

CuringCuring

Helpful Hints:Helpful Hints: Spray concrete with water every Spray concrete with water every

day of the first weekday of the first week Covering the concrete with Covering the concrete with

plastic or a tarp plastic or a tarp Allow the concrete to cure for Allow the concrete to cure for

at least 7 days prior to driving at least 7 days prior to driving vehicles on it.vehicles on it.

Page 58: Planning and Placing Concrete Planning and Placing Concrete

Review / SummaryReview / Summary

Describe how to plan the job.Describe how to plan the job. Discuss preparation for the Discuss preparation for the

concrete pour.concrete pour. Explain placing, finishing, and Explain placing, finishing, and

curing concrete.curing concrete.

Page 59: Planning and Placing Concrete Planning and Placing Concrete

The End!The End!