Chapter 10

Question 1

The single most important factor in determining the ultimate strength of concrete is?

Answer 1

The water to cement ratio

Question 2

Hardening of concrete involves a chemical process known as_____, in which water combines with the particles of cement to form a microscopic gel

Answer 2

Hydration

Question 3

During the hardening of concrete, heat is given off by the chemical process

Answer 3

Heat of hydration

Question 4

Quality control of concrete:

Normal design strength is reached?

Answer 4

After 28 days

Question 5

Concrete in the process of curing must be maintained at the correct temperature, ideally between?

Answer 5

50 and 70°F

Concrete cured at or above 100°F will not reach its proper strength

Question 6

Collapse of precast concrete:

Prestressed concrete systems may be more vulnerable to failure than ordinary reinforced concrete. The systems use reinforcing cables and rods made of high-strength steel’s that can yield at temperatures as low as?

Answer 6

752 degrees Fahrenheit

Question 7

Ordinary reinforcing:

Concrete beams are frequently cast in the shape of a?

Answer 7

Tee

Question 8

The primary function of placing reinforcing steel and concrete is too?

Answer 8

Resist tensile forces

Question 9

Ordinary reinforced:

The steel can also be used to support some of the compressive forces. Vertical reinforcing bars are known as___and are provided to resist the?

Answer 9

Stirrups

Diagonal tension

Question 10

Concrete framing systems:

The simplest and most economical floor system

Answer 10

Flat plate

Question 11

Plain floor slab about 8 inches thick that rest on columns spaced up to 22 feet apart and depends on diagonal and orthogonal patterns of reinforcing bars for structural support because the slab lacks beams

Answer 11

Flat plate

Question 12

A simple system that consist of a concrete slab with concrete columns for support

Answer 12

Flat slab concrete frame

Question 13

Flat slab concrete frame:

The slab of concrete ranges and thickness from_to_.

Answer 13

6-12”

Question 14

Flat slab concrete plate:

In a building that will support heavy live loads, the area around the columns is reinforced with additional concrete in the form of?

Answer 14

Drop panels or mushroom capitals

Question 15

Flat slab concrete frame:

If the building will support light loads, this additional reinforcing is not necessary. The system is the known as a?

Answer 15

Flat plate

Question 16

Slab and beam framing:

The spacing often gives an appearance similar to wood joist and is sometimes referred to as?

Answer 16

Concrete joist construction

Question 17

Slabs in this type of construction can be as thin as 2 inches.

Answer 17

Slab and beam framing

Question 18

Consist of a concrete slab supported by concrete beams

Answer 18

Slab and beam framing

Question 19

Slab and beam framing:

When the concrete beams run mainly in one direction, the framing is known as a?

Answer 19

One way reinforced slab

Question 20

This design provides a thicker slab while illuminating the weight of unnecessary concrete in the bottom half of the slab

Answer 20

Waffle construction

Question 21

Slab and beam concrete framing featuring concrete beams running into directions is known as?

Answer 21

Two way slab construction

*waffle construction

Question 22

This construction is used where spans are short and floor loading are high

Answer 22

Warfel construction, two-way framing SYSTEM

Question 23

Reinforcing steel placed in the bottom of the formwork provides reinforcement in two directions

Answer 23

Waffle construction

Question 24

Structural steel beams can replace concrete beams to support a poured concrete slab.

Answer 24

Concrete plus structural steel

Question 25

Other precast components are cast at the site and moved into position

Answer 25

Tilts up panels.

Precast concrete

Question 26

A major disadvantage to using precast concrete is the need to?

Answer 26

Transport the finished components to the job site

Question 27

Advantages to using precast concrete include:

Answer 27

Higher degree of quality control possible. Work can proceed more quickly at the job site. Precast concrete sandwich panels can be produced using a poly steering core to improve insulating properties of the precast concrete

Question 28

Precast concrete slabs for floor systems can be cast in standard shapes that include:

Answer 28

Solid slabs, hollow core slabs, single T slabs, and double T slabs

Question 29

Precast concrete slabs:

Solid slabs are used for short spans up to approximately?

The tea slabs can be use for spans up to?

Answer 29

30ft

120ft

Question 30

This style of construction requires that the roof assembly maintain structural integrity. Failure of the roof can result in failure of the wall from outward horizontal forces

Answer 30

Tilt up construction

Question 31

Reinforced wall panels are cast at the job site in horizontal casting beds

Answer 31

Tilt up construction

Question 32

Type of construction and which concrete wall sections are cast on the concrete floor of the building in tilted up into the vertical position

Answer 32

Tell Top construction. Also known as tilt slab construction

Question 33

Precast connections:

Supports for precast beams may include___ cast into the columns

Answer 33

Korbels, brackets)

Question 34

Several methods of reinforcing concrete include:

Answer 34

Ordinary reinforcing and prestressing