Name: Date: Binder #:

Concrete Guided Notes

Objective A: Explain the composition and characteristics of concrete

Concrete is a mixture of 4 items:

Cement and water harden and fuse the aggregates together into a substance.

Advantages of Concrete

Disadvantages of concrete

Agricultural uses of concrete

Ingredients in concrete

-No in sand or gravel

-Clean water with no

-Mixed in a - - ratio

-1 part , 2 parts , 3 parts

-Different for different jobs or types of aggregate

-Water

-Add water and thoroughly

-if mix is crumbly -

-if mix is soupy -

Objective B: Place concrete

Calculating concrete needed

-Sold by the or “yard”

-Cubic Yards =

-T is -W is -L is -27 is

-Order a little extra-

-I want to pour a 10’ by 12’ 6 inch pad, how many yards do I need?

◦ .5’ x 10’ x 12’ = 60 cubic feet

◦ 60/27 = 2.22 cubic yards

-How many yards if:

-4’ x 8’ 4 inch pad = -20’ x 50’ 6 inch pad =

Concrete Forms

-Forms hold in the desired shape and location until it .

-Commonly or .

- forms so they aren’t moved out of place

-Wood or metal stakes nailed with

-Coat forms with oil to prevent sticking

-___________ of form will determine the top of the cement slab

-Use a ____ on the form to create the desired of the slab

-Base inside the form should be or compacted firmly

-Forms can be removed after concrete

Reinforcing Steel

-Steel rods or wire added to increase

-Called

-Place in a

- ____ or___________ together where they cross for strongest reinforcement

-Should be in __ of slab vertically and not too close to

Concrete Tools

1. 2. 3. 4. 5.

6. 7. 8. 9. 10. 11.

Placing concrete

- so water doesn’t leave concrete too soon- Have everything ready - - and work continuously to the other side- Concrete is very heavy

Striking off ( )

-Rest straight board (screed board)

- across top of forms in a sliding motion

-

- on unleveled side can drag concrete to low areas

-Tap form boards will hammer or use a spade between board and concrete to push

away from form

Floating

-Float is used to

-Brings and to the surface for smooth finish

- float

- , aluminum or hand float

-Done immediately after striking off

Edging

-Edger used to

-Pushes course aggregate

-Keeps edge from

Jointing

-Creating or in the concrete

-Gives

- along grooves rather than across pad

Finishing

-Creates final surface

- to set up a little then finish

-Float finish is acceptable for some areas like livestock feed areas, has

- gives some traction, pull a over surface

-Metal trowel rubbed over the surface makes a very

-Dip in to aid process

-Excessive troweling makes , may break off and crumble

- may be dragged across surface to make it less

Curing

-Proper and of concrete

-Dries too quickly, doesn’t reach

-The slower the leaves the the concrete

-Protect from , heat or

-Water can be sprayed on concrete to slow drying after it is setup

-At least 7 day wait before