Nb Block 3 Retaining Walls

Front 1

Back 1

Gabion Basket

Front 2

A retaining wall that relies on it's own mass and setback for stability

Back 2

Gravity wall

Front 3

A retaining wall that combines wall mass, set back, and tiebacks reinforcement such as geogrid

Back 3

Reinforced wall

Front 4

Batter

Back 4

Angle created by wall setback

Front 5

Clay bearing capacity

Back 5

2500lbs per square foot

Front 6

Sand bearing capacity

Back 6

4000 lbs per square foot

Front 7

Excess loads and or weight that may be present above a retaining wall

Back 7

Surcharges

Front 8

2 types of drainage

Back 8

Surface

Subsurface

Front 9

The biggest opposition for retaining walls

Back 9

Water

Front 10

Drains behind walls should be daylighted how often?

Back 10

Every 50ft

Front 11

What type of stone material is recommended behind all retaining walls?

Back 11

3/4 inch

Drainage stone

Front 12

Back 12

Woven geotextile

Front 13

Back 13

Non woven geotextile

Front 14

Minimum crushed stone base in our climate

Back 14

6 to 8 inches

Front 15

How thick should lifts be when preparing your base?

Back 15

3- 4 inches

Front 16

Compaction should reach __% proctors density

Back 16

95%

Front 17

How is proctor density measured?

Back 17

Nuclear density gauge

Front 18

Prepped Base of retaining wall should be how wide and how thick?

Back 18

24inches wide

6-8 inches thick

Front 19

What type of pipe should be used for drainage behind a retaining wall?

Back 19

4 inch perforated pipe

Front 20

Minimum grade for drainage

Back 20

1%

Front 21

Rule of thumb to determine how much of the base block should be buried

Back 21

1 inch buried for every foot of height

Front 22

When beginning to place base course of a wall, where is the best place to start?

Back 22

Lowest elevation

Front 23

How far back from the wall should drainage be installed?

Back 23

Minimum 12"

Front 24

Consolidation zone behind a wall

Back 24

3 feet distance behind a wall that no machines are allowed to drive on

Front 25

In a drystone wall, what should the largest stones be used for?

Back 25

Foundation stones

Front 26

Top stones on a drystone wall

Back 26

Copestones

Front 27

In a dry stone wall, these longer stones act as tiebacks

Back 27

Through stone

Front 28

In a dry stone wall, these are strategically placed filler pieces between large stones.

Back 28

Harding

Front 29

Ideally through stones should be placed no further than ___ apart

Back 29

1 meter

Front 30

The ends of a dry stone wall

Back 30

Wall head

Cheekend

Front 31

Supporting structure behind a wood retaining wall.

Buried underneath backfill once the wall is finished.

Back 31

Tieback.

Deadman is attached to the end of the tieback

Front 32

What should be done to the first row in a wood retaining wall to ensure it remains secure?

Back 32

Hammer 2' lengths of rebar into pre drilled holes

Front 33

How much batter should there be when installing a timber retaining wall?

Back 33

1/2" to 3/4"

Front 34

What size galvanized spikes should be used to secure the lower courses of a timber retaining wall?

Back 34

10" galvanized

Front 35

These are timbers that are placed perpendicular to the wall and secured to the wall with spikes

Back 35

Tiebacks

Front 36

How often should a tieback be installed when adding courses to a wall?

Back 36

On the second course, and every other course after that

Front 37

How far apart should tiebacks be spaced apart?

Back 37

8'

2.5m

Front 38

How long should a tieback be?

Back 38

Equal to,or greater than the height of the wall