USBR ch 7

Question 1

What are the conditions that must occur before a rockfill dam can prove to the economical?

a) earthfill materials are difficult to obtain or regulate extensive processing before use
b) short construction seasons prevail
c) the dam is tp be raised at later date
d) all above

Answer 1

d) all above

Question 2

Does uplift pressures and erosion caused by seepage through a rockfill dam generally cause probelms?

a) no, due to saturation and evaporation
b) no, rockfill materials do not generally constitute significant design problems
c) yes, because of sedimentation
d) none above

Answer 2

b) no, rockfill materials do not generally constitute significant design problems

Question 3

Name materials that are used as impervious material in a rockfill dam

a) steel
b) tile
c) wood
d) concrete
e) fiberglass
f) earth material

Answer 3

a) steel

c) wood
d) concrete

f) earth material

Question 4

Two advantages of using an internal membrane in a rockfill dam are shorter grout curtain lengths and less total area exposed to water

T or F

Answer 4

True

Question 5

Bedrock foundations that are soft and erosion resistant are the most desirable for a rockfill dam

T or F

Answer 5

False

Question 6

Limited settlement is critical in the construction of rockfill dams because excessive settlement may rupture the upstream membrane or cause joint separation with subsequent water loss.

T or F

Answer 6

True

Question 7

Name some advantages of asphaltic concrete

a) flexibility
b) can tolerate larger settlement than reinforced concrete
c) economical alternative to concrete
d) dependable when correctly constructed
e) all above

Answer 7

e) all above