Term
| bulk mechanical properties |
|
Definition
density
modulus
damping
yield strength
tensile strength
hardness
compressive strength
shear strength
bending and torsional strength
fracture toughness
fatigue strength
thermal fatigue resistance
creep strength
impact strength |
|
|
Term
| bulk non-mechanical properties |
|
Definition
thermal properties
optical properties
magnetic properties
electrical properties
chemical properties
acoustical properties |
|
|
Term
|
Definition
oxidation and corrosion
fraction
abrasion
wear |
|
|
Term
|
Definition
ease of manufacture
fabrication
joining
finishing |
|
|
Term
|
Definition
ratio between the change in length and the original length (delta L /L)
dimensionless(in/in) |
|
|
Term
|
Definition
measure of a force acting on a unit area
sigma= force/(cross sectional area)
compression
tension
axial/normal
direct
shearing
bending/flexural |
|
|
Term
|
Definition
| tao=shear load/(original cross sectional area) |
|
|
Term
|
Definition
gamma=change in angle alpha + change in angle Beta
shear deformation/unit length |
|
|
Term
|
Definition
v=lateral strain/axial strain
change in deformation is proportional laterally and axiallly |
|
|
Term
|
Definition
relative measure of deformability of a material under a load
measure in terms of modulus of elasticity |
|
|
Term
|
Definition
| ability to retain length, volume or form after the load is applied and removed |
|
|
Term
|
Definition
| maximum stress below which a material will fully recover its original form upon the removal of applied forces |
|
|
Term
|
Definition
| maximum stress below which the ratio between stress and strain is constant (elastic modulus) |
|
|
Term
|
Definition
limit of elasticity
the stress is constant but the material is stretching without increase in the load
point at which the material yields |
|
|
Term
|
Definition
| largest value of stress that can be applied before fracture of the material |
|
|
Term
|
Definition
| plastic strain + elastic strain = yield strain |
|
|
Term
|
Definition
elastic modulus
MOE in tension, compression and shear
ratio of stress to strain below proportional limit
Youngs modulus= compression or tension |
|
|
Term
|
Definition
MOE differs between tension and compression
eg. rubber & biological materials |
|
|
Term
|
Definition
| MOE in tension and compression the same |
|
|
Term
|
Definition
|
|
Term
|
Definition
allows material to undergo change of form without breaking
wrought iron, steel, copper |
|
|
Term
|
Definition
% elongation of fracture
% change in cross sectional area |
|
|
Term
|
Definition
| (final length-original length) / original length x 100 |
|
|
Term
|
Definition
negligible plasticity, easily fractures
concrete, mortar, brick, glass |
|
|
Term
|
Definition
ability to hold loads even after yielding or crack formation
area under entire stress-strain diagram |
|
|
Term
|
Definition
surface property
resistance to indentation or scratching |
|
|
Term
|
Definition
| viscous like a liquid but is elastic like a solid |
|
|
Term
|
Definition
time dependent response
elastic strain, rebound and recovery
may not return to zero |
|
|
Term
|
Definition
| relaxation of stress over time. |
|
|
Term
| bulk density/specific weight |
|
Definition
mass in oven dry condition
volume=solid volume + void volume
most mineral aggregates 95-105 pcf
mass of unit volume at specific temperature |
|
|
Term
| apparent specific gravity |
|
Definition
density of particles based on solid volume / density of h2o
depends on temperature |
|
|
Term
|
Definition
density of particles based on solid volume and pore volume/ density of h2o
depends on temperature |
|
|
Term
|
Definition
volume of pores/ total volume of particles
granite & limestone ~1%
sandstone ~3%
some limestone/sandstone ~13%-30% |
|
|
Term
|
Definition
(SSD weight-oven dry weight)/ oven dry weight x 100
weight absorbed by OD to SSD = max water absorbed
indicator of quality |
|
|
Term
| tangent and secant modulus of elasticity |
|
Definition
| taking the tangent and secant on the MOE graph to find the best numerical value for MOE |
|
|
Term
| compressive strength for aggregate vs concrete |
|
Definition
| compressive strength of aggregate is stronger than compressive strength of concretes containing that aggregate |
|
|
Term
| abrasion resistance and wear resistance |
|
Definition
| determines the suitability for roads and pavement |
|
|
Term
|
Definition
| mechanical wearing and scraping of rocks surfaces by friction, impact or both |
|
|
Term
|
Definition
measure of resistance to fracture under applied loading, slow loading or impact loading
limestone < sandstone/granite |
|
|
Term
Amorphous Materials
define
examples |
|
Definition
materials with atoms arranged almost randomly, not crystalline- strong but brittle
soot, glass |
|
|
Term
brittle materials
define
examples |
|
Definition
little or no elongation or increase in length at fracture
cast iron, concrete and glass |
|
|
Term
cementitious materials
define
examples |
|
Definition
materials in which the principle binder is portland cement or other cement-porous
concrete, mortar, grout |
|
|
Term
ceramic materials
define
examples |
|
Definition
materials based on clay, crystalline, brittle, non conductors and can withstand high temperatures, mostly elastic. used for insulation
glass, cement, stone, brick |
|
|
Term
composite materials
define
examples |
|
Definition
two or more materials are combined on a macroscopic level resulting in elements.
paper, reinforced concrete, reinforced polymers, wood |
|
|
Term
|
Definition
| materials with the ability to deform under a load without permanent deformation up to the elastic limit |
|
|
Term
|
Definition
soluble in carbon-disulphide
softens when heated
water proof & adhesive properties |
|
|
Term
|
Definition
|
|
Term
|
Definition
| viscous black liquid obtained by destructive distillation of coal, wood, shale, etc. |
|
|
Term
|
Definition
| subjected to heat and pressure with no access to air |
|
|
Term
natural asphalts
types & sources |
|
Definition
trinidad lake
gilsonite
petroleum asphalt |
|
|
Term
|
Definition
practically pure asphalt
very hard |
|
|
Term
|
Definition
from refining petroleum
primary source of asphaltic materials |
|
|
Term
| asphalts used for paving and road construction |
|
Definition
petroleum asphalts
emulsified asphalts |
|
|
Term
|
Definition
| suspension of small globules of one liquid into another without intermixing |
|
|
Term
| asphalts used for roofing |
|
Definition
semi solid of solid
shingles or roof rolling |
|
|
Term
| asphalts used for protective coating |
|
Definition
highly blown asphalt
used for canal linings, pipe coating and finely divided mineral fillers |
|
|
Term
|
Definition
dark brown powdery substance
hard with highest viscosity |
|
|
Term
|
Definition
polymer with adhesive property to asphalt cement
medium viscosity |
|
|
Term
|
Definition
solvent
volatile
very low viscosity |
|
|
Term
|
Definition
metallic elements
(nickel, sulfur, etc) |
|
|
Term
|
Definition
adhesion
consistency
specific gravity
durability
rate of curing
ductility
aging & hardening
Resistance to Reaction of Water |
|
|
Term
| properties of asphalt a function of? |
|
Definition
|
|
Term
|
Definition
| measures the degree of fluidity of plasticity of asphalt cement at any particular temperature |
|
|
Term
|
Definition
| measure of the resistance to flow |
|
|
Term
|
Definition
method of measuring viscosity using poise a basic measure unit
n=shear stress/rate of shear strain
use of viscometer to test at 60C |
|
|
Term
|
Definition
represents a method of measuring viscosity using stoke as basic unit. resistance to flow under gravity
=viscosity of liquid/density of liquid
1 stoke=1 cm^2/s
same test as abs, but at 135C |
|
|
Term
|
Definition
measures cements ability to deform without breaking
stretches at rate 5cm/min |
|
|
Term
|
Definition
measures shear loading
n=Fd/Av |
|
|
Term
|
Definition
| measures the consistency of viscosity of solid and semisolid asphalt materials |
|
|
Term
|
Definition
|
|
Term
|
Definition
| property rending fairly stiffer materials like a fluid when vibrated/agitated |
|
|
Term
|
Definition
| point at which the temperature of the binder becomes soft |
|
|
Term
|
Definition
mass of given volume of material at 77F or 60F/equal volume of H20 at same temp
measured using pychometer |
|
|
Term
|
Definition
| asphalt cements and aggregates mixed at hight temperature, places and compacted on roads while still hot |
|
|
Term
|
Definition
|
|
Term
| desired properties of HMA |
|
Definition
stability/resistance to permanent deformation
fatigue resistanc
resistance to thermal cracking
resistance to aging and hardening
resistance to misture induced damaging
skid resistance
workability |
|
|
Term
| Stability of HMA depends on |
|
Definition
distribution of loads by point to point contact of aggregate particles
degree of interlocking among aggregate particles
cohesiveness supplied by asphalt cement |
|
|
Term
| for maximum stability of HMA: |
|
Definition
aggregates are to be crushed in angular particle shape
just enough asphalt to coat the particles |
|
|
Term
| stability of HMA is reduced if: |
|
Definition
particles are rounded or soft
volume of particles in mixture is small |
|
|
Term
|
Definition
resistance of the pavement to disintegration under traffic loads
~remains smooth during summer heat
~crack free during cold
~resists forces of freezing and thawing |
|
|
Term
| for maximum HMA durability |
|
Definition
compromise stability and skid resistance
coating all aggregates with asphalt and filling all voids
impermeability to water and oxygen must be increased |
|
|
Term
|
Definition
| ability of a pavement to withstand deflections and bending without cracking |
|
|
Term
| to maximize HMA flexibility |
|
Definition
use open graded aggregate mixtures
*compromises stability |
|
|
Term
| causes of skid resistance in HMA |
|
Definition
pavement bleeding--leave air voids
aggregate polishing--use hard aggs or mix of hard aggs |
|
|
Term
|
Definition
| non-linear visco-elastic, visco-elastoplatic materials which respond to dynamic loads due to traffic |
|
|
Term
| asphalt concretes fail due to: |
|
Definition
rutting
fatigue cracking
bleeding or flushing
raveling
stripping
thermal cracking |
|
|
Term
|
Definition
| accumulation of permanent deformation in the wheel path |
|
|
Term
|
Definition
| cracking due to repeated bending of the asphalt concrete layer |
|
|
Term
|
Definition
| migration of binder at the surface |
|
|
Term
|
Definition
loss of bond between cement and aggregates due to moisture
**potholes** |
|
|
Term
|
Definition
| variation of temperature--> more cracks |
|
|
Term
|
Definition
constant pressure applied for 3600 seconds, measure deformation at 1,10,100, 1000 and 3600 seconds, remove load and test at same times.
J=epsilon/sigma |
|
|
Term
| marshall stability test( performance test) |
|
Definition
used for ranking various asphalt concretes/mixes
measures stability and flow |
|
|
Term
|
Definition
allows mix designs to be specified for certain conditions easily
allows generally "substandard" materials to be used
tests used as control tests and design tests |
|
|
Term
|
Definition
test not always applicable to all mixes (low viscosity)
lab equipment more elaborate- requires skilled people
test temperatures higher than asphalts are generally subjected to |
|
|
Term
| asphalts used for pavements |
|
Definition
asphalt cements
asphalt cutbacks
asphat emulsions |
|
|
Term
| asphalt cements used for pavements |
|
Definition
mixing placement compaction
most common binders in pavements
needs heating before application |
|
|
Term
| asphalt cutbacks for pavement |
|
Definition
dissolve in lighter weight hydrocarbon solvents
expensive due to high cost solvents
air pollution |
|
|
Term
| asphalt emulsions used for pavement |
|
Definition
dispersing asphalt in water as emulsion
asphalt cement broken down into micron-sized globules |
|
|
Term
| classification of asphalt binders |
|
Definition
performance grading
aged residue grading
penetration grading |
|
|
Term
|
Definition
superpave
high pavement temps measured 20mm below surface
design low temp warmer than 28C calculated at pavement surface |
|
|
Term
|
Definition
| based on absolute viscosity of asphalt after it has been conditioned to simulate effects of aging |
|
|
Term
| types of asphalt cutbacks |
|
Definition
rapid-curing cutbacks
medium-curing cutbacks
slow-curing cutbacks |
|
|
Term
|
Definition
volatile solvent
hard residue
cure time 5-10 mins |
|
|
Term
|
Definition
medium hardness residue
cure time- a few days |
|
|
Term
|
Definition
|
|
Term
| asphalt cutbacks grades defined |
|
Definition
| defined by kinematic viscosity at 60C |
|
|
