Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
83 Cards in this Set
- Front
- Back
according to grain sizes, according to cohesive property |
soil classification |
|
the load that will be transmitted by the superstructure to the foundation system, the requirements of the local building code, the behavior and stress-related deformability of soils/rocks that will support the foundation system, the geological conditions of the soil under consideration |
design of foundations of structures generally requires a knowledge of factors such as: |
|
foundation |
lowest part of the structure |
|
foundation |
its function is to transfer the loads of the structure onto the soil where it rests |
|
foundation bed |
ground where foundation rests |
|
distribute the load of the structure over a large bearing area, adjust loads to prevent unequal settlement, prevent the lateral movement of the supporting material, secure a level and firm bed for building operations, increase the stability of the structure as a whole |
foundations functions |
|
strength limit |
bearing capacity or how much stress (force per unit area) can be carried by the soil |
|
serviceability limit |
how much deformation (in case of foundation, settlement usually) is allowed so that function is not impeded |
|
strength limit, serviceability limit |
foundation limits |
|
settlement, capacity |
relevant parameters |
|
settlement |
foundation dimensions, compressibility, permeability |
|
capacity |
strength parameters of soil like angle of friction and cohesion, unit weight, ground water table location |
|
total, differential |
kinds of settlement |
|
total |
settlement of the structure as a whole (almost same settlement for all points) |
|
differential |
settlement differences between points (usually footings) on a structure |
|
general shear, local shear, punching shear |
foundation failures based in strength |
|
shallow, deep |
types of foundation |
|
less than 4 |
depth-of-embedment-to-width ratio of shallow foundations |
|
isolated spread footings, wall footings, combined, strap, mat foundation |
kinds of shallow foundations |
|
isolated spread footings |
footings under individual column which may be square, rectangular, or circular |
|
strip/wall/continuous footing |
made as a continuous slab strip along the length of a wall |
|
combined footing |
footing that supports 2 or more columns (due to columns being too close/footings overlapping) |
|
cantilever/strap footing |
similar to combined footings, except that the footings under columns are built independently, and are joined by strap beam |
|
raft/mat foundation |
large continuous footing supporting all the columns of the structure |
|
raft/mat foundation |
foundation for poor soil where footing will end up being too big but using pile is not desired/justified |
|
driven, bored |
types of deep foundation |
|
deep foundation |
used when the top layers are not good enough to carry the structure |
|
deep foundations |
used to transfer loads to a stronger layer (may or may not bedrock) which may or may not be located at a significant depth below the ground surface |
|
skin friction, end bearing |
the load is transferred through _________ and _________ |
|
F.s. = failure limit / used |
factor of safety |
|
near vertical excavations |
excavation done whenplutonic/intrusive igneous rocks (granite/gabbro), highly weather resistant like gneiss, quartzite, hornfels |
|
drilling, blasting, ripping, digging |
excavations on rocks |
|
hardness |
drilling factor that dictates how strong the drilling bit should be |
|
abrasiveness |
drilling factor that is the wear effect in drill bits; related to hardness; affected by shape and texture |
|
grain size |
drilling factor that is the size of particles as it is drilled; large particles cause scratches but less wear while smaller particles may polish the drill bits |
|
discontinuities |
drilling factor that affect the ease of drilling |
|
pre-splitting |
creation of shear surface using controlled blasts/drillholes |
|
ripping |
breaking of rock just enough to enable economic loading of rocks |
|
intact strength, fracture index, abrasiveness |
factors affecting ripping |
|
intact strength, bulk density, bulking factor, water content |
factors affecting digging |
|
rock bursting |
rocks suddenly busting from the sides of a tunnel (due to dissipation of accumulated residual stress) |
|
popping |
similar to rock bursting but milder and sides bulge out |
|
standup time/ bridging capacity |
time a rock mass can remain unsupported after tunneling |
|
rock bolts, shotcrete, steel arches |
tunnels can be supported by: |
|
reservoirs |
the body of water that has been controlled by a man using a dam |
|
location of dam, runoff characteristics, watertightness of reservoir basin and sides, stability of sides, sedimentation, possible seismic effects |
factors affecting reservoir site |
|
reservoir |
main use is to control flow, satisfy demand and regulate flow (save for use later; reduce flow to reduce damage) |
|
dam |
an engineering structure constructed to contain water and act as storage |
|
concrete, earth, soil |
what is dam typically made of |
|
aggregates |
rock fragments that are combined to produce certain mixtures (sand, gravel) |
|
trade names |
aggregates can be described by usually related to rocks the aggregates came from |
|
suitability |
aggregates can be described by covers characteristics like shape and texture, contamination, gradation, specific gravity, bulk density, and results of petrographic examination and mechanical tests (usually to determine strength) |
|
earthfill |
from unconsolidated sediments. usually compacted to be improved as it is used as fill |
|
dimension stone |
rocks cut to desired size and used directly as slaps, blocks, or columns although this has been mostly replaced by concrete use |
|
unrestrained slope |
an exposed ground surface that stands at an angle with the horizontal |
|
fall, topple, slide, spread, flow |
slope failure modes |
|
fall |
these motions are characterized by quick movement of various slope materials, such as rocks and boulders, which detach from steep slopes of cliffs due to gravitational actions and mechanical weathering. The slope material moves by bouncing, rolling or free-fall |
|
topple |
this failure, caused by gravitational action or forces exerted by adjacent materials, is distinguished as a forward rotational motion about a pivot point located at the lower portion of the failure unit |
|
spread |
lateral spreads often occur on very gentle slopes. it is characterized by lateral extension with shear or tensile fracture often caused by liquefaction of soil material as a result of naturally or artificially induced rapid ground motion |
|
flow |
this type of landslide may be described as a continuous movement of slope material with short-lived, closely spaced and often not preserved shear surfaces. the speed of motion may range from slow and steady movement (creep) to rapid movement (debris flow, earthflow, mudflow) |
|
slide |
this is a more restrictive term used specifically for mass movement with a distinct zone of weakness where there is evident separation of slide material and the underlying stable material |
|
translational slide |
a type of slide where the slope material moves along a roughly planar surface with little tilting and rotation |
|
rotational slide |
a mass movement where there is evident curved, concavely upward rupture surface |
|
slope gradient |
it is commonly viewed as a major contributing factor in landslide formation. it is the most important factor that needs to be taken into account as the principal factor in landslide susceptibility assessment |
|
elevation |
it is attributed to other factors such as slope, lithology, weathering, precipitation, ground motion, soil thickness, and land use. As an example, mountainous regions often experience relatively larger volume of precipitation causing more landslide occurence |
|
slope aspect |
the exposure of slope, which may be described with respect to the cardinal directions, may affect the distribution of landslide occurrence |
|
slope aspect |
it may be associated with more sunlight exposure, differential weathering and erosion |
|
slope gradient, elevation, slope aspect |
morphologic factors |
|
soil, geology, precipitation, exposure, road network, water bodies |
non-morphologic factors |
|
faults |
weakness zones in rocks where movement may occur |
|
volcanic, tectonic: interplate, intraplate |
kinds of earthquake |
|
source, path, site |
earthquake factors |
|
source |
fault related parameters |
|
path |
path wave attenuation |
|
site |
local amplification/deamplification |
|
primary, shear |
types of body waves |
|
body wave |
wave that travels through interior of earth |
|
primary wave |
fastest wave; push and pull; travels through rock and fluids |
|
shear wave |
second wave felt in an EQ; travels through soild only; moves perpendicular to direction of propagation |
|
surface waves |
wave that travels only along the crust |
|
love, rayleigh |
types of surface waves |
|
magnitude |
measurement of earthquake through the energy released |
|
intensity |
earthquake measurement that is about the effect on a site |