Concrete

Question 1

Concrete

Answer 1

Aggregate, Cement, Water, and Admixture

Question 2

Portland Cement

Answer 2

Lime, Silica, Alumina, Gypsum

Question 3

How long does Cement take to reach full strength?

Answer 3

28 Days

Question 4

Isolation (expansion) Joint

Answer 4

Provide for lateral movement between slabs. Extend the full depth of the Concrete

Question 5

Concrete Qualities

Answer 5

Strength, Durability, Stability, Availability, Adaptability, and Low-cost

Question 6

Properties of Concrete

Answer 6

Constituents, Skills used in placing

Question 7

Concrete resistance to freeze/thaw and deicing chemicals

Answer 7

Apply admixtures

Question 8

Concrete resistance to abrasion and wear

Answer 8

Increased if the concrete mix contains well-graded strong aggregate

Question 9

Methods of Concrete Placement

Answer 9

Cast in Place, Sprayed, Mixed in Place

Question 10

Process of Hydration

Answer 10

Cement and Water mixture results in hardening

Question 11

Types of Aggregate for Concrete

Answer 11

Sand, Gravel, Crushed Stone

Question 12

Selection of Aggregate for Concrete

Answer 12

Resistance to abrasion, Performance, Resistance to effects of freezing/chemicals, Range of Aggregates

Question 13

Admixtures

Answer 13

Workability, Reduce Moisture, Increase durability, Resistance to Freezing, Accelerate or retard hardening or setting, Increase Flowability

Question 14

Water Quality for Concrete

Answer 14

Potable Water (Uncontaminated)

Question 15

2 Styles of Mixing Concrete

Answer 15

Ready-mix and On-site Mixing

Question 16

Slump Test

Answer 16

Determines Relative Consistency & Reflects changes in the amount of water in the mix

Question 17

Air Content Test

Answer 17

Determines the air entertainment at the time of use

Question 18

Cylinder Test

Answer 18

Determines the compressive strength of cured concrete

Question 19

Site Preparation for Use of Concrete

Answer 19

Granular sub-base over-prepared, and compacted, subgrade

Question 20

Benefits of Reinforcement

Answer 20

Controls cracking and give greater tensile strength

Question 21

Purpose of Joints

Answer 21

Minimize damaging effects of expansion and contraction in concrete due to temperature variations and the presence of moisture

Question 22

Control, or contraction, joints

Answer 22

Designed to restrict the cracking of concrete at predetermined locations. ¼ to ⅓ the thickness of the concrete. At intervals roughly the width of slab

Question 23

Construction Joint

Answer 23

Provide places where the casting of concrete can be stopped

Question 24

Joint Fillers

Answer 24

Joints tend to be filled and sealed to keep out moisture and debris

Question 25

Types of Joint Fillers

Answer 25

Fiber Filler Wood Dividers Plastics, rubber, cork, or metal

Question 26

Joint Sealant

Answer 26

Prevents filler material from bleeding or being squeezed up. Keep out debris. Keep out water

Question 27

Two of the most common types of concrete finishes

Answer 27

Floating and Troweling

Question 28

Colored Concrete One Course Method

Answer 28

Mixing pigments when concrete is created

Question 29

Colored Concrete Two-Course Method

Answer 29

Top or finish surface after laying regular concrete

Question 30

Dry-shake Method

Answer 30

Sprinkling Special pigments on the surface

Question 31

Stains and Paints

Answer 31

Typically done on existing concrete

Question 32

Exposed Aggregate

Answer 32

Resistance to slipping and heavy wear

Question 33

One-course Aggregate Finish

Answer 33

Fine aggregate added to the concrete mix. Hosing or acid washing and brushing Surface retardant applied

Question 34

Two-course Aggregate Finish

Answer 34

Base concrete laid. Concrete topping with aggregate added over base concrete Hosing or acid washing and brushing

Question 35

Seeding Aggregate Finish

Answer 35

Sprinkling aggregate over a freshly placed concrete base

Question 36

Special Non-slip finishes

Answer 36

Floats, trowels, brooms, or dry-shaking grains onto the surface. Grains such as Silicon carbide and aluminum oxide

Question 37

Edging

Answer 37

Prevents chipping | Helps compact and harden

Question 38

Wet Covering

Answer 38

Covering with moisture-retaining fabric | Keeps concrete wet

Question 39

Waterproof paper or plastic sheets

Answer 39

Prevents rapid loss of moisture from the concrete

Question 40

Sprinkling or ponding of water

Answer 40

Effective but expensive | Sand or earth berms to be removed later

Question 41

Curing compounds

Answer 41

Used in conjunction with coverings. Used to help sustain curing

Question 42

Temperature Control

Answer 42

Cover with sheets. Use Heaters

Question 43

Sealers and Glaziers

Answer 43

Prevent or Reduce Moisture Penetration and Chloride Penetration

Question 44

Sealers and Glaziers

Answer 44

Used to waterproof or bring out the natural color

Question 45

Restoration and Repair of Concrete

Answer 45

(1) Removal/Cleaning of Damaged Concrete (2) Concrete or grout is mixed in small amounts (3) Treat damaged areas