問題一覧
1
are interceptor trench drains located parallel to the shoulder of paved highways and airfield runway.
interceptor drains
2
the application of vacuum to the piping system to satisfactorily dewater silty soils because capillary forces tend to hold the pore water.
vacuum dewatering
3
two aquifiers under turbulent flow
done
4
localized underground flow that occurs through seams or a stratum of pervious soil presents a potential seepage problem for the structure.
underground springs
5
the type of soil in this excavation is coarse and the method is “open drainage or interceptor ditches”
dewatering shallow excavations
6
it indicates a disorderly random path for moving water particles with lines of movement crossing and frequently moving at an angle or contrary to the general direction of flow.
turbulent flow
7
a blanket or layer of filter material placed beneath the floor slab to provide a highly permeable drainage path for removal of groundwater.
blanket drains
8
It is conventionally placed around the building exterior at footing level and adjacent to the footing.
foundation drains
9
2 methods to accelerate consolidation
sand drains and wick drains
10
a subsurface drainage of fine-grained soils achieved by imposing a surface load onto an area resulting to decrease in water content followed by increase in shear strength.
consolidation drainage
11
3 methods employed under dewatering intermediate depths
done
12
A well or well point is made the cathode, pore water will then migrate toward the negative electrode (cathode).
electro - osmosis
13
small excavation or pit provided in the floor of the structure, or in the earth, to serve as a collection basin for the surface water and near-surface underground water.
sump
14
are a pictorial method of studying the path that moving water flows. are composed of flow lines and equipotential lines drawn together that form mesh strands
flow nets
15
Type of soil: coarse grained to silty Depth: more than 1 meter or a few feet below groundwater level
dewatering intermediate depths
16
the action or method of removing subsurface water by means of channels, pipes or geosynthetics to render the area or structure useful.
drainage
17
lines connecting points in the flow lines that are of equal total energy head.
equipotential lines
18
Three conditions that take place simultaneously in consolidation drainage:
done
19
localized underground flow that occurs through seams or a stratum of pervious soil presents a potential seepage problem for the structure.
underground springs
20
it is understood that excavations extend below water table thus dewatering procedures will be required to keep the work area dry.
drainage during construction
21
read the purposes and benefits of drainage
done
22
is necessary due to limited height of lift for deeper excavation.
multistage dewatering
23
read the effects of soil type: page 24
done
24
are conditions where excavations extend deep below groundwater table or penetrate through a deep permeable stratum.
deep drainage
25
the perforated end section of a well pipe that permits the groundwater to be drawn into the pipe for pumping.
well points
26
lines representing the path the water flows.
flow lines
27
it is the procedure used to remove water from construction area, such as pumping from an excavation or location where water covers the planned working surface.
dewatering
28
the lowering of the level of the groundwater table that occurs in the vicinity of a water well (on dewatering equipment) when it is pumped.
drawdown