WorksheetsTopic 2 Excavation and Construction Dewatering
Total questions: 12
Worksheet time: 6mins
To conduct subsurface construction work, the earth has to be excavated and it is important to consider surrounding movements. To hold the ground surface against topple, what is needed to be installed?
ground water
ground mixer
ground support
For shallow excavation of dry sand and clay for a long-term stability, it can be acceptable to leave certain safe slope to prevent the sides of the ground against topple. The angle of the slope shall be _______.
equal to the angle of friction of the soil
equal to half of the angle of friction of the soil
For a large excavation, select one or more reason(s) for it to be infeasible/unsuitable to provide just a safe slope along side wall.
too large span
expensive
consume time
For ground support installation, which of the following is the general way for sands and silts?
the sheeting is driven up to the excavation level, then lateral bracing is connected as excavation proceeds with depth
the sheeting is driven to a depth below the excavation level, then lateral bracing is connected as excavation proceeds with depth
For ground support installation, which of the following is the general way for stiff clay and weak rocks?
the sheeting is driven to a depth below the excavation level, then lateral bracing is connected as excavation proceeds with depth
the sheeting is installed in open or partially completed excavation to a depth below the excavation level, then lateral bracing is connected
the sheeting is installed in open or partially completed excavation up to the excavation level, then lateral bracing is connected
Construction Dewatering means to keep the excavated area ____.
Dry
Wet
Partially Wet/Dry
Select the dewatering process suitable for shallow excavation and water table up to a depth of 1 m.
Ditches and sumps
Well-points
Vacuum Dewatering
Deep-well Pump
Select the dewatering process suitable for excavating water table up to a depth of 7 m for coarse soil.
Ditches and sumps
Well-points
Vacuum Dewatering
Deep-well Pump
Select the dewatering process suitable for excavating water table up to a depth of 20 m for coarse soil.
Ditches and sumps
Well-points
Vacuum Dewatering
Deep-well Pump
Select the dewatering process suitable for excavating water table up to a depth of 5 m for silts.
Ditches and sumps
Well-points
Vacuum Dewatering
Deep-well Pump
In the context of soil permeability, which soil's well spacing design will be much further apart than the other?
Coarse sandy gravel
Silt
In the context of the depth of an impermeable stratum, the well spacing design of which condition will be much further apart than the other?
Great depth
Shallow depth
