Conventional Concrete Foundations

Question 1

What does the flat-bar system require?

Answer 1

Plywood labels (typically 18 mm thick)
and flat form ties with steel waler bars.

Question 2

What is the typical plywood panel thickness for flatbar framing?

Answer 2

18 mm thick

Question 3

What are done benefits of the flat-bar system?

Answer 3

Cost
Flexibility
Ease of erection

Question 4

______ panel is designed specifically for concrete forming.

Answer 4

Formply. Special adhesives and chemically treated veneers help resist the corrosive action of the concrete.

Question 5

What two purposes to form ties serve?

Answer 5

1. Keep the two forms apart at the required wall thickness.

2. Keep the two forms together during placement of concrete.

Question 6

Flat bar system uses metal ties also called ____ ____.

Answer 6

Strip-ease tie

Question 7

Tie spacing is usually 8 inches from edges and 16 inches apart. T or F

Answer 7

T

Question 8

Flat bars (waler bars) are ___ thick and ____ wide

Answer 8

6 mm

19 mm

Question 9

Walers prevent the ties from falling out of the tie holes and assist in aligning the forms.
T or F

Answer 9

T

Question 10

Flat-bar systems usually use what two methods of holding corners. What add they?

Answer 10

Brackets or hinges

Question 11

_____ are pieces if lumber that are used to plumb, straighten and steady the forms.

Answer 11

Braces.

Question 12

When is brace most effective in flat bar framing systems?

Answer 12

At an angle of 45 degrees or less from the horizontal and is securely fastened in the upper third of the wall.

Question 13

What should be done to form panels before erection?

Answer 13

Apply a release agent (form oil) to the face of each panel. This makes removal of the panels much easier and minimizes damage to the forms.

Question 14

Window bucks are nailed between inner and outer forms in the flat bar system. T or F

Answer 14

T

Question 15

How much a waler bar occur in a flat bar system?

Answer 15

The end joints of the flat bars must not occur over a joint and the ends must run past the panel joint and must pass through at least one tie in the next panel.

Question 16

Pre-manufactured or patented form systems are also called…

Answer 16

Dura-form or Advance forming system

Question 17

Factory-made plywood panels for dura form systems are 30 mm thick and come in standard widths of 2’. T or F

Answer 17

T. Lengths of 2440 and 3640 are common.

Question 18

Describe modular forming.

Answer 18

Using plywood panels to build wall forms.

Question 19

Steel reinforcement or rebar is placed in foundation walls to help the concrete resist _______ forces.

Answer 19

Lateral

Question 20

_____ pressure is imposed by the soil surrounding the foundation and by moisture within the soil (hydrostatic pressure).

Answer 20

Lateral

Question 21

Is is important to place reinforcement over any opening in the foundation wall, such as doors and windows.
T or F

Answer 21

T

Question 22

When placing rebar you should place the rebar close to the forms or to each other. T or F

Answer 22

F. Placing rebar too close to forms or each other prevents free passage of the coarse aggregate when the concrete is placed in forms.

Question 23

Joints in reinforcing should be lapped ____ times as long as the diameter of the rebar.

Answer 23

24

Question 24

Rebar joints have a _____ mm overlap.

Answer 24

300 mm

Question 25

The two most common methods of attaching floor frame to foundation are:

Answer 25

Anchor bolts

Cast-in-place ladders

Question 26

Anchor bolts must have a minimum thickness of ____ in diameter.

Answer 26

12 mm

Question 27

Layout for anchors must be no more than ____ m from the corners and no more than ____ m spacing from each other. With a depth off ___ mm.

Answer 27

1.2 m
2.4 m
100 mm

Question 28

Fluid concrete causes internal ____ pressure.

Answer 28

Lateral

Question 29

Mechanical vibration can increase pressures on the formwork by ___ to ___ %.

Answer 29

20 to 30 %

Question 30

As temperature increases, the concrete stays in a fluid state for shorter period of time (sets faster).

T or F

Answer 30

T

Question 31

The taller the wall the _____ the lateral pressure will be.

Answer 31

Greater

Question 32

Concrete drops should be no more than ____ to ____.

Answer 32

1.2 to 1.8 feet

Question 33

Consolidation is important because it fills the voids or air pockets, thereby eliminating _______.

Answer 33

Honeycombing

Question 34

The top of concrete should be left approximately ____ mm below the top of ladder to allow for future shrinkage in the wood.

Answer 34

10 mm

Question 35

All sub-surface soil contains moisture bad because of ______ pressure , eventually comes in contact with the foundation wall.

Answer 35

Hydrostatic

Question 36

_____ pressure is the force caused by moisture in the soil.

Answer 36

Hydrostatic

Question 37

To counteract wicking an impervious barrier must be placed between the soil and the concrete foundation
T or F

Commonly done by applying a heavy coat of bituminous material, such as asphalt, to the concrete. T or F

Answer 37

T

T

Question 38

Weeping tile is usually 100 mm to 150 in diameter and is connected to a sewer system or sump pit that carries water away. T or F

Answer 38

T

Question 39

The top of weeping tile must be _____ the top of footing.

Answer 39

Below

Question 40

Cover weeping tile with a minimum of ____ mm gravel.

Answer 40

150mm

Question 41

Basement windows that extend below grade also need a window. T or F

Answer 41

T

Question 42

How many nails should be used to fasten the vertical edge of the plywood panels at an inside corner?

Answer 42

Minimum number of nails

Question 43

What is applied to the form panels to assist in removal of the forms?

Answer 43

Form oil or releasing agent

Question 44

What is the purpose of the latched on pre-manufactured panels?

Answer 44

Hold two adjacent panels together. Attach to the end of the form tie.

Question 45

List. 3 factors that affect lateral pressure on forms when placing concrete.

Answer 45

1. Rate of placement
2. Weather conditions
3. Vibration

Question 46

What is used to hold the panels together at the top during the erection of flat-bar wall form systems?

Answer 46

Horizontal ribbon

Question 47

In residential construction, which type of tie is used with the built-in waler bad latch panel form system?

Answer 47

Double notched tie

Question 48

For backfilling purposes how high above the grade line must a concrete foundation wall extend?

Answer 48

150 mm