Traffic Terms
Hydraulic Terms
Structures Terms
Common words and terms used in this manual are defined in this section. Definitions for other words or terms that may call for clarification in this manual are found in the “Construction and Materials Specifications.”
AASHTO - American Association of State Highway and Transportation Officials.
ASTM - American Society of Testing and Materials.
CAS - Construction Administration System, a part of CMS which provides support to all construction administration activities from the time at which a contract has been signed to the time at which the contract has been finalized.
Change Order - A written order issued by the Director to the Contractor, covering changes in the plans or quantities or both, within or beyond the scope of the contract and establishing the basis of payment and time adjustments for the work affected by the changes.
Contractor - The individual, firm or corporation contracting with the Ohio Department of Transportation for the performance of prescribed work, acting directly or through a duly authorized representative and qualified under provisions of the law.
Conversion - The adaptation of one unit of
measure to another unit of measure. Examples:
Density - The relation of weight to
volume. The greater the weight to a given volume, the greater the density.
Department - The Ohio Department of
Transportation.
Director - The Director of the Department
of Transportation, the Administrative head of the Department of Transportation,
appointed by the Governor.
Documentation - Recording and filing evidence
that the material or work is in conformance with specifications in the amounts
determined.
Elevation - The height as measured from a predetermined point denoted in the plans.
Engineer - The person representing the
Department who is charged with the overall responsibility at the project site
for seeing that construction is in conformance with plans and specifications,
and that all checks for job control and validation of pay items are documented
and filed properly.
FHWA - Federal Highway Administration, U.S. Department of Transportation.
File - The complete project file in the
field office in which is placed all progress records and documentation of pay
items.
Inspection - Examination by observation,
measurement, or tests to determine that materials and work are in conformance
with specifications.
Inspector’s Daily Report - A form used by an inspector to document the activities performed by a Contractor. The Inspector Daily Report is Form CMS-1CA-D-3A or CA-D-3B.
Laboratory (Laboratory with “L” capitalized) -The Office of Materials Management of the Department of Transportation, 1600 West Broad Street, Columbus, Ohio 43223. If reference is to the District laboratory, it is so designated.
Lane or
Traffic Lane - A
strip of pavement of specified width, usually 12 feet (3.6 m).
P.E./P.S. Daily Report - A form used by the Engineer or Project supervisor to document the activities performed by a Contractor. The P.E./P.S. Daily Report is Form CMS-2CA-D-4.
Pay
Item - A
specifically described unit of work for which a price is provided in the
contract.
Plans - The plans, profiles, typical cross sections, working drawings and supplemental drawings, approved by the Director, or exact reproductions thereof, which show the location, character, dimensions, and details of the work.
Progress
Samples - Samples
taken by Laboratory or project personnel not engaged in job control sampling.
Samples are obtained at random from materials delivered for incorporation in
the work to provide an independent spot check on the reliability of the results
obtained in job control sampling and testing.
Project - The specific section of the
highway together with all appurtenances and construction to be performed
thereon under the contract.
Proposal - The offer of a bidder, on the
prescribed form properly signed and guaranteed, to perform the work and to
finish the labor and materials at the prices quoted.
Project Engineer - The person representing the Department who is charged with the overall responsibility at the project site for seeing that construction is in conformance with plans and specifications, and that all checks for job control and validation of pay items are documented and filed properly.
Standard Drawings - The Standard Construction Drawings issued by the Bureaus of Location and Design, Bridges and Design Services.
Specifications - The directions, provisions and requirements contained in the State of Ohio, Department of Transportation Construction and Material Specifications as supplemented by the supplemental specifications and special provisions.
TAS - Testing Administration System, a part of CMS which provides support to all sampling, testing and approval or disapproval of materials used on a project, to the time at which the contract has been finalized.
Tolerance - The allowable limits of variation from a specified measurement.
Transition - The distance in which a change is made gradually from one pavement cross section to another.
Verification - The steps necessary to determine that the work or materials described are in conformance with plans and specifications.
A ggregate - Mineral material, such as sand, gravel, crushed stone, slag, or combinations hereof.
Asphalt Concrete - A mixture of aggregate and asphalt binder. Types of asphalt concrete are 301, 302, 442, 446, and 448.
Batch Plant - A plant in which dry, hot aggregate and asphalt material are proportioned in fixed or batched quantities into a pugmill (mixer) for mixing. Then the resulting asphalt concrete is either batched directly into a haul truck or stored in a storage bin for later use.
Asphalt Concrete Base - A type of asphalt concrete which is used as a base course in the construction of a pavement. Two types of asphalt concrete base are 301 and 302.
Asphalt Binder- A thermoplastic binding material obtained as a residue in the distillation of petroleum, which may contain additives to enhance performance.
Bleeding - The rising of an excess of asphalt material to the surface of an asphalt concrete mixture.
Checking - Short transverse cracks, 1 to 4 inches (25 to 100 mm ) in length and 1 to 3 inches (25 to 75 mm) apart, which develop in the surface of the asphalt concrete mat during the compaction process.
Choke - Aggregate used for the purpose of filling the surface voids of a coarse aggregate mixture.
CMS – Multiple definitions as follows:
Coarse Aggregate - Aggregate which is retained on the No.4 (4.75 mm) sieve.
Compaction - A consolidation or compression of materials resulting in an increase in density of the materials.
Compression Rolls - The compaction load of a steel wheel roller, expressed in pounds per inch (kN/m), which is defined as the weight of the roller divided by the combined width of all the drums on the roller. The compression rolls requirements for rollers are specified in 401.13.
Course - A layer or layers of a given material or mixture placed as a part of the pavement structure.
Cross Section - In the field, elevations taken along a line at right angles to the centerline. On a drawing, a profile of the existing ground at right angles to the centerline. The drawing of an earthwork cross section also shows the shape of the finished excavation or embankment at the same point. A roadway cross section shows the thickness and width of the pavement courses.
Cross-Slope - The transverse slope of the pavement, either crown or superelevation. See section 401.19 for details on checking the cross-slope of a pavement.
Crown - The height of the center of the roadway surface above a straight line drawn between its edges. See section 401.19 for details on checking the crown of a pavement.
Cut Back Asphalt - Asphalt binder which has been rendered fluid by fluxing it with a light volatile petroleum distillate. Upon exposure to atmospheric conditions, the volatile distillate evaporates, leaving only the asphalt cement which reverts to its original semi-solid condition. Cut back asphalts are classified as rapid curing (RC), medium curing (MC), or slow curing (SC).
Degradation - A reduction in aggregate particle size due to breakage and water.
Density - The ratio of the weight of a given material to its volume.
Drum Mix Plant - A continuous production plant in which cold aggregate is proportioned and dried in the first half of a drum and then mixed with bituminous material in the second half of the drum. Then the resulting asphalt concrete is stored in a storage bin for later use.
Asphalt Emulsion - A suspension of extremely small droplets of asphalt in water in the presence of an emulsifying agent, which usually is a type of soap. Upon exposure to atmospheric conditions, the water evaporates, leaving only the asphalt cement which has been modified by the emulsifying agent. Emulsions are classified as rapid setting (RS or CRS), medium setting (MS or CMS), or slow setting (SS or CSS). The letter “C” in front of an emulsion type (CRS, CMS, or CSS) denotes a cationic (positively charged) emulsion. If the emulsion type does not start with the letter “C” (RS, MS, or SS), the emulsion is anionic (negatively charged) or non-ionic (neutral charge). If the emulsion type is followed by an “h” (SS-1h, CMS-2h, etc.), the emulsion was made from a harder base asphalt cement.
Fat Spots - See the definition of bleeding.
Fine Aggregate - Aggregate which passes the No.4 (4.75 mm) sieve.
Flushing - The drawing of asphalt material to the surface of an asphalt mixture, due to the action of traffic.
Gradation - The distribution of particle sizes in an aggregate or asphalt mixture.
Grade - The rate of change of the profile elevations. See section 401.19 for details on checking the grade of a pavement.
JMF - See the definition of job mix formula.
Job Control - Inspection and testing conducted to determine compliance of the materials and work with the contract requirements.
Job Mix Formula - The mix composition of an asphalt concrete approved by the Laboratory. The job mix formula (JMF) of a mix can be obtained from the “BCJMF” screen in the TAS portion of CMS. The JMF number of the mix needs to be known to use the “BCJMF” screen.
Keying - The interlocking of aggregate particles by compaction.
Laboratory - The Office of Materials Management of the Department’s Central Office in Columbus, which is also known as the Central Test Lab.
Marshall Mix Design - Volumetric mix design procedure used to establish the optimum Asphalt binder content for an asphalt concrete. The procedures for designing a mix using the Marshall mix design are contained in 441.02 and the Asphalt Institute Manual Series No. 2.
Mineral Filler - limestone dust, portland cement, or other inert mineral matter. The specifications for mineral filler are contained in 703.07.
NAPA - National Asphalt Pavement Association.
NCAT - National Center for Asphalt Technology.
Odometer - An instrument used for measuring traveled distance.
Oscillating Wheel - The vertical movement of pneumatic tire roller’s wheels over irregularities in the surface on which the roller is operated, providing a kneading action.
PG (Asphalt) Binder - An asphalt binder which has been graded by the PG Binder system. An asphalt binder has to be modified with an additive to meet some of the PG Binder grades. An example of a PG Binder Grade is PG 64-28. An example of a modified PG Binder Grade is PG 70-22M (See Asphalt Binder).
Placement Rate - The placement of paving materials on the basis of a given weight and area covered. Placement rate is described in detail in section 401.21.
Plant - The plant where aggregate and asphalt material are mixed together or the plant which produces the aggregate or the asphalt material.
Pneumatic Tire Roller - A roller with 3 to 5 rubber tires mounted on two tandem axles. The wheels that the tires are mounted to oscillate, which means they are capable of moving up and down independently of each other. The pneumatic roller compacts a pavement using the combined force of weight and the kneading action of the oscillating wheels. The specifications for a pneumatic tire roller are contained in 401.13.
Prime Coat - An application of asphalt material made on the surface of a pavement layer for the purpose of binding the surface particles together. The specifications for a prime coat are contained in 408.
Profile - A line on a drawing which shows elevation of points along a selected route. A profile usually shows both ground elevations and grade-line elevations. See section 401.19 for details on checking the profile of a pavement.
RAP - The abbreviation for reclaimed asphalt pavement, which comes from reclaimed asphalt concrete pavement. The specifications for the use of RAP is contained in 401.04 and 441.03.
Raveling - The loss of aggregate from the surface of a asphalt mixture due to a lack of adequate compaction, segregation of the mixture, moisture damage, high dust content, or a lack of PG binder for binding the aggregate particles together.
Screed - A rectangular trowel on an asphalt paver used to cut off the asphalt mixture at the desired thickness, to smooth the surface and consolidate the material.
Screenings - This is No. 10 size gravel, stone, or air-cooled slag. The specifications for screenings are contained in 703.10.
Segregation - The separation of the coarse and fine particle sizes in an aggregate or asphalt mixture.
Shoving - The plastic deformation or displacement in an asphalt mixture in the direction of traffic movement.
Steel Wheel Roller - A roller which compacts an asphalt concrete with static steel drums. Types of steel wheel rollers are the three-wheel roller, tandem roller, trench roller, and vibratory roller.
Strike Off - A blade used to cut off material at the desired elevation or thickness.
Superelevation - The difference in elevation between the inside and outside edges of a roadway on a horizontal curve. See section 401.19 for details on checking the superelevation of a pavement.
Superpave - Mix design procedure, which establishes material properties of an asphalt concrete mix by using a gyratory compactor and material requirements.
Surface Texture - A term used to describe the appearance of the surface of a pavement course such as sandy, coarse, open, dense, uniform, etc.
Surface Treatment - See the definitions for chip seal, prime coat, or tack coat.
Tachometer - An instrument for measuring the speed of rotation.
Tack Coat - An application of asphalt material made on a pavement surface for the purpose of bonding the existing course to the overlying course. The specifications for a tack coat are contained in 407. Tack coats are described in Section 6.
Tandem Roller - A steel wheel roller with two drums mounted on tandem axles, which compacts a pavement using the force of the roller’s weight. The specifications for a tandem roller are contained in 401.13.
Three Wheel Roller - A steel wheel roller with three drums, two drums mounted on the rear axle and a smaller drum mounted on the front tandem axle, which compacts a pavement using the force of the roller’s weight. The configuration of the drums on a three wheel roller allows it to compact longitudinal joints without interfering with traffic in the adjacent lane. The specifications for a three wheel roller are contained in 401.13.
Vibratory Roller - A steel wheel roller with one (single drum) or two (double drum) drums, which compacts a pavement using the combined force of weight and the vibration of the drum or drums. The specifications for a vibratory roller are contained in 401.13.
Viscosity - Resistance to flow in a liquid. The higher the viscosity, the greater the resistance to flow.
Yield - The area of a surface covered by a given quantity of material measured in square yards (square meters)..
Absorption - The soaking up of moisture
(water) by aggregate.
Admixture - A substance other than cement,
water or aggregate added to a batch of fresh concrete to alter one of the
normal properties of concrete.
Aggregate - Mineral material, such as sand, gravel crushed stone, slag, or
the combinations thereof, with which cement or bituminous material is mixed to
form a mortar or concrete. "Fine Aggregate" may be considered as the
material that will pass a 1/4 inch screen, and "coarse aggregate" as
the material that is retained thereon.
Aggregate
Base - The layer
of specified, compacted material placed on the subgrade to serve as a base for
pavement.
Agitation - Slow stirring or turning over of
freshly mixed concrete to keep it in workable condition until placed into
forms.
Air
Entrained Cement
-Cement into which the air entrainment admixture has been incorporated at the
cement plant when the cement was ground.
Batch - The combination of amounts of
cement, aggregate, water and admixture which will be mixed at one time in a
mixer.
Batching
Operation -
Proportioning and assembling the materials which will comprise one batch.
Batching Plant - The plant either on or off the work site where the materials
are assembled by batches for the mixer. Water and admixtures usually are added
as the batch is introduced into the mixer.
Batch
Weights -The
individual weights of the cement, aggregate and water used in each batch of
concrete. Aggregate is adjusted for moisture content and specific gravity.
Bleeding -Flow of water to the surface of
freshly placed concrete.
Bulkhead -
Cement - A mixture of clay, limestone and
other selected materials heated to high temperature to form clinker. The
clinker is then ground into powder. Mixed with water it forms a paste to
surround and bind the aggregate into a solid and durable mass.
Charging - Filling. Charging a mixer is
placing the ingredients for concrete into it.
Compacted - Made more dense. When a material
is compacted, the particles are forced together more tightly so that a given
weight of material takes up less space.
Concrete
Control Inspector -
The Inspector at the job site who is responsible for the necessary inspections
and tests to assure concrete meeting specifications.
Counters -Meters on mixers which show the
number of revolutions. Transit mixers may have two counters - one for mixing
speeds and one for agitation speeds.
Cure - The treatment given concrete to
assure sufficient water and heat necessary for chemical action so that concrete
attains the strength and durability for which it was designed.
Entrained
Air - Millions of
microscopic voids introduced into concrete through an admixture to permit the
cured concrete to undergo freezing and thawing without damage.
Entrapped
Air - Large air
bubbles which enter concrete through mixing or handling. Being undesirable,
they can be removed by vibrating, spading or rodding.
Falsework - The bracing supporting concrete
structural forms which is removed after the concrete has cured sufficiently to
support its own weight.
Finishing - Shaping the surface of cement
that is not shaped by forms. Also it includes filling visible voids in the
concrete after the forms are removed.
Footer - The concrete pad which spreads
the load of a structure over an area of supporting earthwork.
Forms,
Report - Printed
sheets of paper containing blank spaces for filling in desired information.
Forms,
Structural - Molds
of rigid material for receiving plastic concrete which will cast it to a
specified shape and dimension.
Gradation - The classification of different
sizes of aggregate within a given size of aggregate as determined by sieve
tests.
High-Early-Strength
Concrete -
Concrete made with a special cement (Type III111) that reaches design strength
and hardness in considerably shorter time than concrete made with regular
portland cement.
Honeycombing - Large voids in the concrete
which are due to inadequate spading or consolidating.
Intermingling - The unintentional dilution of
one size of aggregate by aggregate of a different size as a result of improper
storage or careless handling.
Job
Control - Steps
taken to keep quality and quantity of materials and work on a project within
the specifications and plans.
Mixing - Combining the ingredients of a
batch of concrete into a homogenous mass through raising and dropping action of
a revolving drum. Specifications cover the rate and number of revolutions which
are acceptable for proper mixing.
Moisture
Content - The
percentage by weight of water contained in aggregate as compared to the same
aggregate in a completely dry condition.
Mortar - A mixture of water, sand and
cement. Mixed with coarse aggregate this mortar completely envelopes each
particle of coarse aggregate to form concrete.
Paved - An area covered with a hard
surface to support traffic or material storage.
Plant
Bins - Bins at the
hatching plant for temporary storage of aggregate and cement for use in
proportioning concrete batches.
Proportioning
Concrete -
Determination of the amount of each ingredient used in a class of concrete with
adjustments as determined by tests called for in the specifications.
Retarder - An admixture placed in concrete
which slows the setting of the concrete.
Rodding - Consolidation of a concrete mix
sample by the repeated insertion of the prescribed steel tamping rod.
Saturation - Condition of aggregate when it
is completely soaked and will not absorb additional water.
Scaling - Peeling away of small amounts of
surface concrete.
Segregation - The unintentional separation of
the larger pieces of aggregate from the smaller pieces within one size of
aggregate or within a mixture of sizes in fresh concrete.
Set, or
set up - A stage
reached by freshly placed concrete as it hardens and can no longer be worked or
shaped.
Sieve
Analysis -
Determination of the gradation of an aggregate sample by passing through a
series of screens with specified openings and weighing the separated particle
sizes.
Slump - A measure of the consistency and
workability of plastic concrete.
Spading - Repeatedly inserting a flat
steel blade edgewise into fresh poured concrete for consolidation and to drive
out entrapped air, particularly where the concrete meets the forms or imbedded
objects.
Spading
Blade - A small
steel blade about the size of a nail file, used in making Chace air
determinations.
Spading
Tool - A tool
resembling a garden hoe with the blade straightened out in line with the handle
used for consolidating concrete.
Spalling - The breaking away of hardened
parts of concrete from the main body at surface points.
Specific
Gravity - The
ratio of weight of any volume of a substance to the weight of an equal volume
of water.
Specifications
- The directions,
provisions and requirements contained in the State of Ohio Department of
Transportation Construction and Materials Specifications as supplemented by the
supplemental specifications and special provisions.
Stabilize - To make or hold steady, and
preventing fluctuations.
Stockpile
- A large amount of aggregate placed in a pile for storage until ready for use.
Strike Off - Using a straight edge to scrape off excess concrete which may
protrude above the mold or forms.
Subgrade - The portion of a roadbed upon
which the pavement structure and shoulders are constructed.
Testing
Equipment - That
equipment furnished to the project for conducting field tests.
Test
Weights - Ten 50-pound
(22.7 kg) steel weights that must be readily available for checking weighing
devices at concrete plants.
Ticket - A form record of quality,
quantity, and other pertinent information which may accompany a shipment of
construction materials to the project.
Validation - The signature or initials of an
authorized individual on any form or ticket denoting that the information is as
stated.
Verification - The steps necessary to determine
that the work or materials described are in conformance with plans and
specifications.
Water-Cement
Ratio (W/C) - The
proportion of an amount of water to the specified amount of cement used to
produce concrete. Such amount of water is the sum of the calculated amount of
water contained in the aggregates, plus all the water added both at the plant
and at the site, less the calculated amount of water absorbed by the
aggregates.
Yield - A check on the mix design made by dividing the total batch weight by the determined unit weight, weight per cubic yard (weight per cubic foot). The actual volume thus obtained is compared to the design volume.
Admixture - A substance other than cement, water or aggregate added to a batch of fresh concrete to alter one of the normal properties of concrete.
Aggregate - Mineral material, such as sand, gravel, crushed stone, slag, or the combination thereof, with which cement is mixed to form a mortar or concrete. “Fine aggregate” may be considered as the material that will pass a 4.75 mm (No. 4) screen, and “coarse aggregate” as the material that is retained thereon.
Batch - The combination of amounts of cement, aggregate, water and admixture which will be mixed at one time in a mixer.
Batching Plant - The plant either on or off the work site where the materials are assembled by batches for the mixer. Water and admixtures usually are added as the batch is introduced into the mixer.
Beam, Test - A beam of specified size molded on the job and later broken in a testing machine to determine the flexural strength of the concrete.
Bleeding - Flow of water to the surface of freshly placed concrete.
Cap - A short tube, closed at one end, placed on the oiled end of a dowel in an expansion joint to provide space for movement of the dowel in hardened concrete. A stop in the tube prevents it from being pushed all the way onto the dowel before the concrete hardens.
Cement - A mixture of clay, limestone and other selected materials heated to high temperature and ground into powder. Mixed with water it forms a paste to surround and bind the aggregate into a solid and durable mass.
Contraction Joint - A joint which controls the location of a transverse crack and permits the slab to contract and expand with changes in temperature.
Construction Joint - A joint formed in concrete pavement at the end of the day’s production or any time production is interrupted for 30 minutes or longer.
Core - A cylinder of concrete cut from pavement with a hollow drill. Cores are 4 inches (200 mm) in diameter and are used to check the thickness and strength of the concrete.
Course - The depth of concrete pavement obtained in one pour.
Crown - The height of the center of the roadway surface above a straight line drawn between its edges.
Cure - The treatment given concrete to assure sufficient water and heat necessary for chemical action so that concrete attains the strength and durability for which it was designed.
Curing Membrane - A compound sprayed over the exposed surface and edges of newly placed concrete to prevent the evaporation of water during curing.
Cylinder - A test sample of concrete molded into a cylinder 12 inches (600 mm) high and 6 inches (300 mm) in diameter, to be sent to the Laboratory for determination of strength and density.
Deformed Bar - A steel bar which has projections on its surface for increasing the bond between the concrete and the bar.
Density (Soil) - The density of soil is its weight-volume relationship, which usually is expressed in kilograms of soil per cubic meter (pounds of soil per cubic foot).
Dowel or Dowel Bar - A smooth steel bar extending across a concrete joint to transfer the applied load, prevent future misalignment of the slab and permit movement at the joint.
Dowel Assembly - A cage or basket used to hold dowels in position during placement of concrete.
Edging - Rounding the edges of concrete pavement and hand-formed joints while the concrete still is workable, using an edging tool of specified radius.
Elevation or Grade - The height as measured from a predetermined point denoted in the plans.
Expansion Joint - A joint adjacent to a bridge or intersection to absorb expansion of concrete pavement and prevent expansive pressure on the bridge or intersecting pavement.
Fine Grading - Removing approximately 1 inch (25 mm) of the primary subbase and re-rolling to bring to exact grade, upon which the concrete pavement is placed.
Finishing - Shaping the surface of concrete that is not shaped by forms. Also it includes filling visible voids in the concrete after the forms are removed.
Finishing Machine - A machine which screeds and a float for performing the final grade and smoothness of the concrete pavement to meet the requirements.
Float - A straight piece of wood or metal used to smooth the surface of plastic concrete. Small hand-held floats are called paddle floats.
Forms, Pavement - Metal plates secured together and to the subbase for shaping the sides of the pavement and controlling alignment, grade and thickness. Also, the forms serve as a track for paving equipment.
Grade (noun) - See Elevation.
Grade (verb) - To add or remove earth to obtain a desired level or slope.
Hand Finishing - Correcting manually irregularities left by the finishing machine or performing those functions which cannot be accomplished by machine, such as edging or forming of joints.
Head - The roll of plastic concrete which forms ahead of a screed plate.
Honeycombing - Large voids in the concrete which are due to inadequate spading or consolidating.
Hook Bolt - A short steel bar with hooked ends joined by a threaded connection. Use is to fasten a concrete slab to another later constructed beside it.
Inspection - Examination by observation, measurement, or tests to determine that materials and work are in conformance with specifications.
Joint Lock - The device at each end of a section of paving form for attaching the sections together.
Job Control - Steps taken to keep quality and quantity of materials and work on a project within the specifications and plans.
Joint Sealer - A compound for preventing entrance of
water and solid particles into a joint. The sealer may either be preformed or
liquid.
Laitance - An accumulation of fine particles on the surface of freshly placed concrete occurring when there is an upward movement of water through the concrete due to the presence of too much mixing water or excessive vibration.
Lane or Traffic Lane - A strip of pavement of specified width, usually 12 feet (3.6 meters).
Longitudinal Joint - A joint which extends lengthwise in the roadway, parallel to the centerline.
Mesh - A fabric of steel wires welded together at their intersections for placement in concrete pavement as distributed reinforcement.
Mesh Installer - A machine for imbedding wire mesh into freshly placed concrete pavement.
Mortar - A mixture of water, sand and cement. Mixed with coarse aggregate, this mortar completely envelopes each particle of coarse aggregate to form concrete. Also, mortar is used to fill honeycombing which becomes apparent upon removal of forms.
Oscillating - To swing back and forth, operating between fixed limits, such as the movement of a screed on a finishing machine.
Pin Template or Template - A device used to check the surface of the subbase.
Raveling - Slightly disturbing the surface of concrete pavement adjacent to sawing of a joint.
Random Cracks - Cracks which appear in concrete pavement due to contraction in the early stages of curing, and which follow no set pattern.
Rigid Pavement Inspector - An authorized representative of the Engineer to make detailed inspections and documentation of contract performance as pertain directly to concrete paving operations.
Sawing - Using a circular saw to cut a groove in the surface of the pavement to control the location of transverse cracks.
Scaling - Peeling away of small amounts of the concrete surface.
Screed - A long metal plate moved across the surface of freshly placed concrete with a sawing motion to consolidate the concrete and rough finish it approximately to grade.
Segregation - The unintentional separation of the larger pieces of aggregate from the smaller pieces within one size of aggregate or within a mixture of sizes of fresh concrete.
Shim - A thin piece of stone, wood or other material used to raise the object resting on it to the desired elevation. (Not permitted in adjusting forms to grade.)
Slab - A continuous portion of concrete paving bounded by joints and/or the edge of the pavement.
Slip Form Paving - Concrete paving by use of a machine carrying its own forms between which low slump concrete is compacted sufficiently to retain its shape after the machine has progressed onward.
Slump - Measured in millimeters (inches) on a vertical axis, the amount that a sample of fresh poured concrete that has filled a standard inverted cone will sink down after the cone has been removed. A measure of the consistency and workability of concrete.
Spading -Repeatedly inserting a flat steel blade edgewise into fresh poured concrete for consolidation and to drive out entrapped air, particularly where the concrete meets the forms or imbedded objects.
Spalling - The breaking away of hardened parts of concrete from the main body at surface points.
Spreader - A machine which distributes fresh concrete generally over the area between the forms.
Station Marker - A numeral impressed into the surface of newly finished concrete pavement and located at specified longitudinal intervals near the edge of the roadway for purposes of future location references.
Straightedging - Placing a 10 foot (3.0 meter) straightedge on the finished pavement surface to determine if the surface is within tolerance.
Strike Off - Using a straightedge to scrape off excess concrete which may protrude above the mold or forms.
Subbase - The layer of specified, compacted material placed on the prepared subgrade to serve as a base for pavement.
Subgrade - The portion of a roadbed upon which the pavement structure and shoulders are constructed after it is prepared.
Surge - The rise in the surface of plastic concrete following the release of compaction after the screed has passed over it.
Texturing - Slight roughening of the finished surface of concrete pavement to provide greater safety through increased traction to the tires of vehicles which will pass over it.
Thin-Bonded Patching - Repairing concrete pavement only to the depth of unsound concrete rather than the full depth of the pavement.
Tie Bar - A deformed dowel or hook-bolt placed across longitudinal joints of concrete pavement near middle depth to tie the slabs together and hold the joint closed.
Tieing - Wiring together overlapped mesh that is hand-tied by use of rings similar to hog rings.
Tolerance - The permitted variation from a specified condition.
Traction Speed - The rate of forward movement parallel to the centerline by the paving equipment.
Transverse - A theoretical line running perpendicular to the longitudinal or centerline of a roadway.
Validation - The signature or initials of an authorized individual on any form or ticket denoting that the information is as stated.
Vibrator - A device for pulsating fresh concrete so that entrapped air is released, and the concrete settles uniformly about reinforcement and to the forms.
Wearing Plate - A small plate which drags over the top of the pavement forms or adjacent paving to control the height of the screed plate.
Windrow - An accumulation of material as a result of rolling up or sliding off to the side. Applies here to loose material just inside of the forms left by the subgrader in the fine grading operation.
Yield - A check on the mix design made by dividing the total batch weight by the determined weight per unit volume. The actual volume thus obtained is compared to the design volume.