CONSTRUCTION TERMS PART 1 (finalize) Flashcards
it may refer to the contractual arrangement under which a firm supplies construction management services to an owner
construction management
includes such activities as specification development, process control, product acceptance, laboratory and technician certification, training, and communication.
quality management
primarily concerned with the process control function
quality control (QC)
the process of moving soil or rock from one location to another and processing it so that it meets construction requirements of location, elevation, density, moisture content, and so on
earthmoving
the ability of a soil to support the weight of vehicles under repeated traffic
trafficability
a measure of the difficulty in excavating and loading a soil
loadability
the bucket volume contained within the bucket when following the outline of the bucket sides
plate line capacity
the bucket capacity when the load is struck off flush with the bucket sides
struck capacity
assumes a level of material flush with the lowest edge of the bucket
water line capacity
the maximum volume that can be placed in the bucket without spillage based on a specified angle of repose for the material in the bucket
heaped volume
a very versatile machine that has the longest reach for digging and dumping of any member of the crane shovel family
dragline
primarily used for lifting, lowering, and transporting loads, which move loads horizontally by swinging or traveling
cranes
represents that component of vehicle weight which acts parallel to an inclined surface
grade resistance
primarily due to tire flexing and penetration of the travel surface
rolling resistance
represents those components of cycle time other than travel time
fixed time
represents the travel time required for a unit to haul material to the unloading site and return
variable time
the process of giving natural soils enough abrasive resistance and shear strength to accommodate traffic or design loads
ground modification or soil stabilization
the process of increasing the density of a soil by mechanically forcing the soil particles closer together, thereby expelling air from the void spaces in the soil
compaction
also known as deep compaction
dynamic compaction
involves dropping a heavy weight from a crane onto the ground surface to achieve soil densification
dynamic compaction
also called vibroflotation and vibrocompaction
vibratory compaction
the process of densifying cohesionless soils by inserting a vibratory probe into the soil
vibratory compaction
placing additional weight on the soil surface, which has long been used to densify cohesive soils
surcharging
refers to the improvement of the engineering properties of a soil by use of physical or chemical admixtures
soil stabilization
the process of bringing earthwork to the desired shape and elevation (or grade)
grading
simply called “finishing”
finish grading
involves smoothing slopes, shaping ditches, and bringing the earthwork to the elevation required by the plans and specification
finish grading
in highway construction, the process of cutting down high spots and filling in low spots of each roadway layer
balancing
the process of bringing each roadway layer to its final grade
trimming
four (4) phases of rock moving process
- loosening
- loading
- hauling
- compacting
produced by mixing Portland cement, aggregate, and water
cement
seven (7) construction operations involved in the production of concrete
- batching
- mixing
- transporting
- placing
- consolidating
- finishing
- curing
concrete that usually weighs from 140 to 160 lb/ft³ (2243–2563 kg/m³), depending on the mix design and type of aggregate used
normal–weight concrete
concrete that may weigh from 15 to 90 lb/ft³ (240–1442 kg/m³) and have a 28–day compressive strength from about 100 to 1000 lb/in² (690–6895 kPa)
lightweight insulating concrete
concrete used in a structure such as a dam in which the weight of the concrete provides most of the strength of the structure
mass concrete
made with heavy aggregates such as barite, magnetite, and steel punchings, which is used primarily for nuclear radiation shielding
heavyweight concrete
concrete having a slump of 1 in. (2.5 cm) or less
no–slump concrete
a measure of concrete consistency obtained by placing concrete into a test cone following a standard test procedure (ASTM C143) and measuring the decrease in height of the sample when the cone is removed
slump
concrete that is suitable for high temperature applications such as boilers and furnaces
refractory concrete
concrete that has been cast into the desired shape prior to placement in a structure
precast concrete
concrete that will be exposed to view and therefore utilizes special shapes, designs, or surface finishes to achieve the desired architectural effect
architectural concrete
five principal types of portland cement, classified by the American Society for Testing and Materials (ASTM) as Types I–V, used in construction
- type I (normal) portland cement
- type II (modified/moderate) portland cement
- type III (high early strength) cement
- type IV (low heat) cement
- type V (sulfate–resistant) cement
a principal type of portland cement that is considered as a general–purpose cement suitable for all normal applications
type I (normal) portland cement
a principal type of portland cement that provides better resistance to alkali attack and produces less heat of hydration than does type I cement
type II (modified/moderate) portland cement
a principal type of portland cement that provides 190% of type I strength after 1 day of curing; it also produces about 150% of the heat of hydration of normal cement during the first 7 days
type III (high early strength) cement
a principal type of portland cement that produces only 40–60% of the heat produced by type I cement during the first 7 days; however, its strength is only 55% of that of normal cement after 7 days
type IV (low heat) cement
a principal type of portland cement that provides maximum resistance to alkali attack
type V (sulfate–resistant) cement
used in concrete to reduce the cost of the mix and to reduce shrinkage
aggregate
required in the concrete mix for several purposes and principal among these is to provide the moisture required for hydration of the cement to take place
water
the chemical reaction between cement and water which produces hardened cement
hydration
the heat that is produced by hydration
heat of hydration
water/cement ratios normally used range from about _____ by weight
0.40 to 0.70
has significantly increased resistance to freezing and thawing as well as to scaling caused by the use of deicing chemicals
air–entrained concrete
increase the slump or workability of a concrete mix
water–reducing agents
with a _____ the amount of water in the mix may be reduced without changing the concrete’s consistency
water–reducing agent
slow the rate of hardening of concrete
retarders
act in the opposite manner to retarders; that is, they decrease setting time and increase the early strength of concrete
accelerators
used to reduce the heat of hydration, increase the workability, and reduce the segregation of a mix
pozzolans
increase the workability of a mix
workability agents or plasticizers
the process of proportioning cement, water, aggregates, and additives prior to mixing concrete
batching
truck-mounted concrete mixers capable of mixing and transporting concrete
truck mixers or transit mix trucks
referred to the product that truck mixers or transit mix trucks deliver
ready–mixed concrete
consists of gravel, crushed stone, or another suitable material larger than ¼ in. (6.4 mm) in diameter
coarse aggregate
are materials other than portland cement, aggregates, and water that are added to concrete either immediately before or during its mixing to alter the properties of the concrete in a variety of ways
admixtures
four (4) uses of admixtures
- improve workability
- reduce separation of coarse and fine aggregates due to settling out of the heavier coarse aggregate
- entrain air
- accelerate or retard setting and hardening
permit a lower water content, improve workability, and increase the efficiency of the portland cement in a mix, which lowers a concrete’s cost relative to its performance
water–reducing admixtures
mostly used in concrete that is to be pumped as they produce a mix that flows easily, with no increase in its water content
high–range water–reducing admixtures (super plasticizers)
admixtures that have a retarding effect on the set of portland cement overcome the accelerating effect that temperature has on setting during hot weather and in large masses of concrete, and delay the early stiffening of concrete placed under difficult conditions
retarders
increase the rate of early strength development in concrete
accelerators
in building construction, it is a form or mold where concrete is placed since it is unable to maintain a particular shape before it sets
formwork
these are made by building a large section of form, as described earlier for centering, and supporting the entire section on deep steel trusses
flying forms
a method of continuously moving a form for vertical structures, such as elevator or stair shafts, upward on jacks as new concrete is placed on top of the old
slip forming
rubber or vinyl inserts designed to be placed in concrete joints to prevent water from penetrating the joint
waterstops
are often necessary to separate concrete sections and prevent the bonding of one concrete section with another, or to separate a concrete section from another material or structural part so that one can move independently of the other
isolation and separation joints
the water-cement ratio selected should be the _____ value required to meet design requirements such as durability, strength, and impermeability
lowest
concrete that will be exposed to a combination of wet-dry and freeze-thaw cycling and de-icing chemicals requires the following five (5) conditions for durability
- a low water-cement ratio
- air-entrainment
- suitable materials
- adequate curing
- good construction practices
one that is readily molded and yet will change its form only slowly if the mold is removed
plastic concrete
concrete is handled and transported by:
- chutes
- push buggies
- buckets handled by cranes
- pumping through a pipeline
- pneumatically forcing through a hose (shotcrete)
concrete is either delivered to the site by truck or, in small projects, mixed at the site and moved to its placement location by:
- dumping directly from a truck’s chute
- buggy
- dumping from a truck’s chute into a large bucket, which is then lifted by crane and deposited in its proper location
- dumping from a truck into a concrete pump which delivers the mix to its final location through a hose
these are capable of delivering concrete over long distances and up many floors
pumps
the movement of plastic concrete into its final position (usually within forms)
placing
pneumatically placed concrete that is used primarily for swimming pools and other in-ground and aboveground free-form structures and for repairing damaged concrete
shotcrete
four (4) reasons why concrete should be compacted by a method appropriate to the material and its location
- eliminate stone pockets and large air bubbles
- consolidate each layer with that previously placed
- completely embed reinforcing and fixtures
- bring just enough fine material to the faces and top surfaces to produce the desired finish
medium to high–slump concrete should be compacted and worked into place by _____
spading or puddling
seven (7) steps (in a defined order) involve in finishing of standard-weight concrete slabs
- screeding
- leveling
- edging
- jointing
- floating
- troweling
- broom finishing or other surface texturing
generally, the dry materials used in making quality concrete are heavier than water; thus, shortly after placement, they have a tendency to settle to the bottom and displace the mixing water to the surface, which is called _____
bleeding
the surface of newly placed concrete is struck off (screeded) by moving a straightedge back and forth with a saw–like motion across the top of the forms and screeds
screeding
the bringing of a concrete surface to true grade with enough mortar to produce the desired finish
leveling
rounds off the formed edge of a slab to prevent chipping or damage
edging
except when joints will be later sawed, immediately following or during edging, premolded inserts are placed in concrete slabs to control cracking in the concrete as a result of shrinkage
jointing
in general, this may be done when the water sheen has disappeared and the concrete will support the weight of the finisher
floating
four (4) purposes of floating involve in finishing of standard-weight concrete slabs
- embed large aggregate just beneath the surface
- remove slight imperfections, humps, and voids to produce a level or plane surface
- consolidate mortar at the surface in preparation for other finishing operations
- open the surface to permit excess moisture to escape
done on slabs that are to be left exposed or to receive thin finishes, such as resilient flooring, carpet, tile, or paint
troweling
brushing or brooming steel-troweled concrete surfaces to be slightly roughened in order to produce a nonslip surface as they are very smooth and become slippery when wet
broom finishing
the breaking away of the hardened concrete surface of a slab to a depth of about 1/6 to 3/16 in. (1.6 to 4.8 mm), which is usually occurs at an early age of the slab
scaling
the occurrence of numerous fine hair cracks in the surface of a newly hardened slab due to surface shrinkage
crazing
the appearance of a powdery material on the surface of a newly hardened concrete slab
dusting
often based on a polymer-modified asphalt (PMA), which is available and has demonstrated high resistance to rutting and cracking as well as to petroleum fuels
fuel–resistant asphalt
liquid at room temperature and is created when petroleum distillates are mixed with asphalt cement
asphalt cutback
contain particles of asphalt dispersed in water by means of emulsifying agents
asphalt emulsions
the _____ of a liquid is the temperature at which it produces sufficient vapor to ignite in the presence of air and an open flame
flash point
capable of spreading, consolidating, and finishing a concrete slab without the use of conventional forms
slipform paver
a thin coating of light bituminous material applied to a previously paved surface to act as a bonding agent
tack coat
a substance applied to an unpaved surface to reduce the amount of dust produced by vehicular traffic and wind
dust palliative
a light application of a slow-setting asphalt emulsion diluted by one to three parts of water
fog seal
composed of a mixture of slow-setting asphalt emulsion, fine aggregate, mineral filler, and water
emulsion slurry seal
composed of a light application of a medium-viscosity liquid asphalt covered with fine aggregates
sand seal
single-pass and multiple-pass surface treatments that are made up of alternate applications of asphalt and aggregate
aggregate surface treatments
constructed by spraying on a layer of asphalt and covering it with a layer of aggregate approximately one stone in depth
single-pass surface treatment
consists of the demolition of old pavement, recrushing of the pavement material, and reusing it in new asphalt or concrete mixes
recycling
