Likeley Questions Flashcards

1
Q

Name 3 rock properties that influence rock mechanical behaviour

A

Cleavage, hardness, solubility

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Name 4 rock characteristics (describing a rock)

A

Type, age, place, structure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

3 rock types

A

Igneous, sedimentary, metamorphic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Describe 3 occurrences of igneous rock

A

Plutonic - high pressure environment, slow cooling, intrusive plutons. Subvolcanic - transitional between intrusive sills and dykes. Volcanic - low pressure environment, fast cooling, extrusive.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

3 types of igneous rock

A

Magma, volcanic, plutonic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

3 volcanic processes

A

Lava, tephra, pyroclastic flows

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What kind of rocks have the most desirable engineering properties and why

A

Intrusive and chrystallie extrusive rocks, they are strong, stable and little movement of water.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What can influence sedimentary rock characteristics

A

Type of material, transportation mechanism, depositional site

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

5 sedimentary rock groups

A

Clastic, bionic, chemical, volcaniclastic, mixed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe the general process of sedimentary rock

A

Weathering (from parent source ruck), erosion and transportation, deposition, accumulation, lithification.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe the lithification process

A

Soil into rock. Layers of soil, compaction, cementation, significant increase in strength.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Clastic classification

A

Clast composition, size, shape, sorting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe 3 metamorphic processes

A

Contact (high heat), dynamic ( deformation and pressure), regional (high heat and pressure).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How con crustal deformation occur

A

Tectonic movements, plutonic deposits and volcanic activity, charge in loading (gravity effects).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What can folding be effected by

A

Temperature, pressure, strain rate, rock type

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Why does direction of bedding matter

A

Stability of structures, movement of water, tunnels and underground structures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

4 planar defects

A

Fractures and joints, cleavage, bedding, lithologic boundaries.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Zonal defects

A

Crushed seam, sheared zone, infill, voids/cavities

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Denudation

A

Process of exposing deposits. Weathering, erosion degradation, transportation - part of the exogenic process

20
Q

Weathering types

A

Mechanical physical, chemical, biological.

21
Q

When classifying rocks what would you write in the main paragraph?

A

Weathering, colour, fabric, rock name.

22
Q

Unweathered

A

Rock mass shows no loss of strength, discolouration or other effects die to weathering. There may be slight discolouration on major rock mass defect surfaces or on clasts.

23
Q

Completely weathered

A

Original rock strength is lost and the rock mass charged to a soil either by chemical decomposition or by physical disintegration.

24
Q

What would you write in the qualifying paragraph

A

Strength, discontinuities, geologic information, characterises the rock mass

25
How could you determine strength (tests)
Unconfined compression test, point load test, rebound hammer
26
Discontinuities
Describe defects within the rock mass. Orientation, spacing, persistence, roughness, wall strength, aperature, infill, seepage, sets, block size and shape
27
ClassifyING roughness
Rough, smooth, slickensided. Stepped, undulating, planar.
28
Soil origins
Transported soils, residual soils, organic soils, volcanic soils
29
Transported soils
**Alluvium** ( rivers and streams clay to gravel size), **colluvium** (mass movement and surface water flow, clay to boulder size), **glacial** ( ice movement, silt to boulder size), **aeolian** (wind, silt size and fire sand), **volcanic**
30
Residual soils
Formed by weathering in place. Decomposition (chemical) disintegration (mechanical)
31
Organic soils
Formed in place by growth and decay of plants, accumulation of fragments of inorganic skeletons or shells of organisms. Low strength and stiffness.
32
Silts vs. Clays
Dilatant behaviour only occurs in silts. Shaking changes distribution of particles.
33
% gravel > % sand
Cu greater than 4 CC between 1 and 3
34
% sand > % Gravels
Cu greater than 6 and CC between 1 and 3 to be well graded
35
Hydrometer test
To determine the grain size distribution, better for fines clays and silts. Based on sedimentation and stokes law. Sampling approach, hydrometer approach,
36
2 tests for attenburg limits.
Casagrande apparatus,, liquid limit cone penetrometer.
37
Sand cone test
To find the bulk density / unit weight
38
Nuclear densometer
Density and water content measurement.
39
Fundamental seepage assumptions
- Flow is laminar, - incompressible flow: conservation of mass, - soil is saturated, - flow is steady state. Seepage is the difference in head between points needed for seepage to occur.
40
What effects the coefficient of permability
Void size, void continuity, soil particle shape, soil particle roughness, viscosity e density of water. Grain size distribution
41
Lab tests to determine K
Constant head test - coarse grained soils. Falling head test- course and five grained soils.
42
Constant head test
Head difference is constant.
43
Falling head rest
Head difference is changing,
44
Seepage parallel to layers
Head loss through each layer is the same, flow rate is split across layers. Hydraulic gradient I same - equivalent characteristics controlled by the most permeable layer.
45
Seepage normal to layers
Head loss through each layer varies. Flow rate is the same. Equivalent characteristics controlled by the most impermeable layer
46
Quick condition or piping
If upward seepage reduces effective stress, at some point seepage could reduce effective stress to zero or negative. No interparticle forces at this point, erosion will occur.
47
Tests to determine grain size distribution
Sieve analysis, hydrometer test