Reinforced Concrete Terminology
AASHTO—American Association of State Highway and Transportation Officials.
ABUTMENT—Supporting substructure at ends of bridges.
ACI—American Concrete Institute
ANCHORAGE—The securing of reinforcing steel in concrete either by straight embedment, hooks, or headed bar
ANSI— American National Standards Institute
ARC WELDING—A process by which the two pieces of steel to be joined are heated by an arc formed between an electrode and the steel. As the electrode melts, it supplies weld material which fuses the pieces of steel together.
ARCHITECT—A person or firm who prepares the architectural drawings that determine the design and form of buildings. The Architect is usually employed by and represents the Owner.
ARCHITECTURAL DRAWINGS—Drawings which show the general design and form of structures by means of elevations, plans and sections; show the various materials such as brick, concrete, glass, masonry, steel, stone and wood and their dimensions; show fixtures and finishes for ceilings, floor surfaces and walls.
ASTM—American Society for Testing and Materials.
AWS—American Welding Society.
AXLE-STEEL REINFORCING BARS—Deformed reinforcing bars rolled from steel axles for railroad cars.
BACK UP BARS—See GRILLAGE BARS.
BAND—Group of reinforcing bars distributed in a slab or wall or footing. See STRIPS.
BANDED TENDONS—Prestressing tendons which are grouped into a narrow “band” 3 to 4 feet wide over the columns. Tendons in the perpendicular direction are spaced uniformly.
BAR—Steel bar used to reinforce concrete. See REINFORCEMENT.
BAR-END CHECK—Check of the ends of reinforcing bars to determine whether they fit the devices intended for mechanically splicing the bars.
BAR LIST—Bill of materials, where all quantities, sizes, lengths and bending dimensions of the reinforcing bars are shown.
BAR NUMBER—A number, approximately the bar diameter in eighths of an inch [whole millimeters], used to designate the reinforcing bar size. For example: A #5 [#16] bar is approximately 5/8 inch [16 millimeters] in diameter: a #9 [#29] bar is approximately 9/8 inches [29 millimeters] in diameter. Bar numbers are rolled onto the bar for easy identification.
BAR OFF—Unloading reinforcing bars from a truck bed by levering individual bundles over the side with pinch bars.
BAR PLACER or PLACER—Worker who handles and places reinforcing steel and bar supports. See IRONWORKERS and METAL LATHER.
BAR PLACING SUBCONTRACTOR—A contractor or subcontractor who handles and places reinforcement and bar supports often colloquially referred to as a “bar placer” or “placer.”
BAR SPACING—Distance between parallel reinforcing bars measured from center-to-center of the bars perpendicular to their longitudinal axes.
BAR SUPPORTS—Devices of formed wire, plastic or precast concrete, to support, hold, and space reinforcing bars.
BASKET—Wire assembly to support and space dowel bars along the expansion joints in concrete pavement.
BEAM—A horizontal structural member supporting loads from a floor or roof system to columns, girders or walls.
BEAM AND SLAB FLOOR CONSTRUCTION—A reinforced concrete floor system in which a solid slab is supported by beams or girders of reinforced concrete.
BEAM BOLSTER—Continuous bar support used to support the reinforcing bars in the bottom of beams.
BEAM BOLSTER UPPER—Continuous bar support for the upper layer of bottom reinforcing bars in beams and top reinforcing bars in bridge deck slabs.
BEAM SCHEDULE—Table on a placing drawing giving the quantity, size and mark number of beams; the quantity, size, length and mark numbers of reinforcing bars and stirrups (including stirrup spacing), and, where specified, the stirrup support bars and beam bolsters.
BELLED—Having a butt or bottom end shaped like a bell, often used on concrete piers or caissons.
BENT—A self-supporting reinforced concrete frame with one or more columns, usually at right angles to the length of the structure it supports. Example: The columns and cap supporting the spans of a bridge is called a bent.
BENT BAR—A reinforcing bar bent to a prescribed shape such as a truss bar, straight bar with end hook, stirrup, or column tie.
BENT CAP—A reinforced concrete beam or block, extending across and encasing the heads of columns, comprising the top of a bent for the bridge span above.
BILL OF LADING—A list that gives each part or mark number, quantity, length of material, total weight, or other description of each piece of material that is shipped to a jobsite.
BILLET—Piece of semi-finished steel, nearly square in section, formed by hot-rolling an ingot or bloom, from which reinforcing bars are rolled.
BOLT CUTTER—A tool used to cut reinforcing bars on the job-site. Smaller (wire) mesh cutters are used to cut welded wire reinforcement or bundle wires.
BOND—Holding or gripping force between reinforcing steel and concrete.
BOX CULVERT—A tunnel-like reinforced concrete structure consisting of single or multiple openings, usually square or rectangular in cross section.
BOX GIRDER—A bridge having a top and bottom slab with two or more walls forming one or more rectangular bays. The wall heights may be variable in order to provide an arched bottom slab.
BRACKET—An overhanging member projecting from a wall, column, girder, or beam to support the weight of a structural member.
BREAK (A SPIRAL)—Opening a spiral to the round shape and forcing it toward the opposite direction that it was folded (collapsed) so that it will remain circular for placing.
BUILDING CODE—Laws or regulations set up by building departments of cities, states and Federal Government, for uniformity in design and construction practices.
BULKHEAD—Partition placed in a form to hold fresh concrete, earth, or water.
BUNDLE OF BARS—A bundle consists of one size, length or mark (bent) of reinforcing bars tied together, with the following exceptions; (1) very small quantities may be bundled together for convenience, and (2) groups of varying bar lengths or marks (bent) that will be placed adjacent may be bundled together. Maximum weight of bundles is dependent on regional practices and site conditions. See LIFT.
BUNDLED BARS—A group of not more than four parallel reinforcing bars in contact with each other, usually tied together.
BURNING REINFORCEMENT—Cutting reinforcing bars with an oxy-acetylene torch.
BUTT-WELDED SPLICE—Reinforcing bar splice made by welding the butted ends.
CAISSONS—Piers usually extending through water or soft soil to solid earth or rock. Also cast-in-place, drilled-hole piles.
CAISSON—See DRILLED PIER.
CANTILEVER BEAM—Beam which extends beyond the supports in an overhanging position with the extended end unsupported. Similarly such a slab is called a cantilever slab.
CARBON-STEEL REINFORCING BARS—Reinforcing bars rolled from steel billets in contrast to rail or axle steel.
CAT-HEAD—A light frame and a sheave at the top of a material tower through which the lifting cable is operated.
CERTIFIED MILL TEST REPORT—A report from the producing steel mill listing the chemical analysis, physical properties, heat or lot number, and specification used to manufacture the material.
CHAMFER—A beveled outside corner or edge on a beam or column, or a triangular wooden strip placed in the corner of a form to create a beveled corner.
CHOKER—A sling hitch that is self-tightening.
COLD JOINT—Construction joint in concrete occurring at a place where the continuous casting has been interrupted.
COLUMN—Vertical structural member supporting a floor beam, girder, or other member, and supporting primarily vertical loads.
COLUMN CAPITAL—Upper flared cone-shaped section (mushroom head) on circular columns; pyramid-shaped section on square columns.
COLUMN HORSE—Wood or metal supports, used in groups of two or more, to hold longitudinal reinforcing bars in a convenient position for placing ties while prefabricating column, beam or pile cages.
COLUMN SCHEDULE—Table on a placing drawing giving the mark number and size for the column, number of pieces and size of vertical bars, ties or spirals and any bar mark numbers required.
COLUMN TIES—Reinforcing bars bent into square, rectangular, U-shaped, circular or other shapes for the purpose of holding column vertical bars in place.
COMPRESSION BARS—Reinforcing bars used to resist compression forces.
COMPRESSIVE STRENGTH-Maximum stress a material is capable of resisting under axial compression loading.
CONCRETE BLOCK BAR SUPPORTS—Precast concrete blocks, with or without tie wires, used to support reinforcing bars above the ground or to space bars off vertical forms and above horizontal forms. Also known as “dobies.”
CONCRETE COVER—The distance from the face of the concrete to the reinforcing steel, also referred to as “Fireproofing,” “Clearance,” or “Concrete Protection.”
CONSTRUCTION JOINT—Separation between two placements of concrete; a means for keying two sections together.
CONTACT SPLICE—A means of splicing reinforcing bars by lap splicing in direct contact. See LAP SPLICE.
CONTINUOUS BEAM—A beam which extends over three or more supports (including end supports).
CONTINUOUS HIGH CHAIRS—Bar supports consisting of a continuous longitudinal upper member with evenly spaced legs used to support reinforcing bars near the top of slabs. See SUPPORT BARS and INDIVIDUAL HIGH CHAIRS.
CONTINUOUSLY REINFORCED CONCRETE PAVEMENT— A pavement without transverse contraction or expansion joints and with sufficient reinforcement to keep transverse cracks tightly closed.
CONTRACT DOCUMENTS—Documents covering the required Work and including the Project Drawings and Project Specifications.
CONTRACTION JOINT—Saw-cut, formed, or grooved joint to allow for shrinkage in a concrete slab.
CONTRACTOR—The person, firm, or corporation with whom the Owner enters into an agreement for construction of the Work.
COUPLER—Threaded device for joining reinforcing bars for the purpose of providing transfer of either axial compression or axial tension or both from one bar to the other.
COUPLING SLEEVE—Non-threaded device fitting over the ends of two reinforcing bars for the eventual purpose of providing transfer of either axial compression or axial tension or both from one bar to the other.
CRIBBING (Also known as DUNNAGE)—Wooden blocks or boards used in a horizontal or vertical position to separate bundles of reinforcing bars.
CRSI—Concrete Reinforcing Steel Institute.
CULVERT—Any structure, not classified as a bridge, which provides a waterway or other opening under a road or highway.
CURTAIN—A single layer of vertical and horizontal reinforcing bars in a wall. If a wall has a layer of reinforcement at each face, it would be called a “double curtain” wall.
CUT-OFF SAW—A powered saw used to cut reinforcing bars at the job-site.
DEFORMED BAR—A reinforcing bar manufactured with deformations (protrusions) to provide a locking anchorage with the surrounding concrete.
DESIGN DRAWINGS—See STRUCTURAL DRAWINGS.
DESIGNING—Preparation of structural drawings to show general arrangement of the structure, size and reinforcement of members, and other information for construction and for the preparation of placing drawings.
DETAILERS—Draftsmen who prepare reinforcing bar placing drawings.
DOLLY—Small, heavy, wheeled platform used for moving heavy objects. Colloquially, any wheeled cart or carrier.
DOBIES—See CONCRETE BLOCK BAR SUPPORTS.
DOG-LEG—See OFFSET BEND.
DOWEL—A bar connecting two separately cast sections of concrete. A bar extending from one concrete section into another is said to be doweled into the adjoining section. Examples: column dowels into a column or horizontal wall bars doweled into an adjacent wall section.
DOWEL SLEEVE—Cap of light metal or cardboard on one end of a dowel bar to allow free movement of an expansion joint.
DOWEL TEMPLATE—Frame which outlines the dimensions for setting dowel bars into footings for columns and walls.
DRAFTSMAN—One who prepares drawings. See DETAILERS.
DRILLED PIER-A drilled shaft usually extending through water or soft soil to solid earth or rock. Sometimes called a “caisson”.
DROP PANEL—The structural portion of a flat slab which is thickened (by “dropping” the form) throughout an area surrounding a column, column capital or bracket.
END-BEARING SLEEVE—Device fitting over the abutting ends of two reinforcing bars for the purpose of ensuring transfer of only axial compression from one bar to the other.
ENDO—The dimension from the end of a reinforcing bar to a point of reference along its longitudinal axis; i.e., any bar is positioned in the forms transversely by “cover” or “spacing” and longitudinally by “cover” or “endo.”
ENGINEER—A licensed professional or structural engineer, responsible for the design of reinforced concrete, structural steel, and other materials which make up the complete structure.
ENGINEERING DRAWINGS—See STRUCTURAL DRAWINGS.
EPOXY COATING—An organic, non-metallic coating applied to reinforcing steel by electrostatic spray to prevent corrosion.
EXPANSION JOINT—A separation between two sections of concrete which is provided to allow for free movement due to temperature changes. The sections are usually divided by a strip of metal or bituminous material and are sometimes tied together with dowels, using sleeves or coatings at one end.
FABRICATED HIGH CHAIR-See STANDEE.
FABRICATION—Actual work on the reinforcing bars such as cutting, bending, bundling, and tagging.
FABRICATOR—A company that is capable of preparing placing drawings, bar lists, and storing, shearing, bending, bundling, tagging, and delivering reinforcing bars.
FAR FACE (OF A WALL)—Face farthest from the viewer, which may be the outside or inside face, depending on whether one is inside looking out or outside looking in.
FILLET—Beveled inside corner usually at 45° to avoid a sharp 90° change in direction at the intersection of two reinforced concrete members. Also refers to a triangular-shaped weld.
FIREPROOFING—See CONCRETE COVER. Also refers to encasement of reinforcing steel for fire protection.
FLAT PLATE SLAB—A flat slab without drop panels or column capitals.
FLAT SLAB—A concrete slab reinforced in two or more directions, with drop panels and with or without column capitals.
FOOTINGS—That part of the foundation of a structure which rests on earth.
FORMS—A temporary structures or molds, usually made of wood, fiberglass, metal or plastic, for the support of concrete while it is setting and gaining sufficient strength to be self-supporting.
FOUNDATION—Substructure through which the loads are carried to the earth or rock.
GALVANIZE—To dip steel into molten zinc, which is termed “hot-dip galvanizing”; or to electroplate with zinc.
GENERAL CONTRACTOR—An individual or company that bids and executes the contract for actual construction, coordinates and supervises the work of the Subcontractors and is responsible for the completion of the Work in accordance with the project drawings and project specifications.
GIN POLES—Single vertical guyed pole for supporting lifting tackle.
GIRDER—Principal beam supporting other beams.
GRADE BEAM—A low foundation wall or a beam usually at ground level, which provides support for the walls of a structure.
GRADE MARKS—Markings rolled onto the surface of reinforcing bar to identify the grade of steel.
GRADE OF REINFORCING BARS—The means by which an Engineer specifies the strength properties of the reinforcing bar required in each part of a structure.
GRILLAGE BARS-Reinforcement placed around post-tensioning anchors. Also known as “back-up bars”.
GROOVE WELD—Arc weld used to join two reinforcing bars, or a reinforcing bar to a steel plate or an angle to make a lap splice.
GROUT—A concrete which contains no coarse aggregate.
HAIRPIN BARS—Bars, usually small sizes, bent to a hair pin shape and used for such purposes as short hooked spacer bars in columns and walls, and for special dowels.
HAUNCH—Portion of a beam that increases in depth towards the support.
HEADER—A short reinforced beam, joist or slab edge generally used at floor openings to support other similar members terminating at the opening.
HEAVY BENDING—Reinforcing bar sizes #4 through #18 [#13 through #57], which are bent at not more than six points in one plane (unless classified as “Light Bending” or “Special Bending”) and single radius bending.
HICKEY—Hand tool with side opening jaw used in developing leverage for making bends on reinforcing bars at the jobsite.
HIGH CHAIR—See INDIVIDUAL HIGH CHAIRS and CONTINUOUS HIGH CHAIRS.
HOOK—A semi-circular (180°) or a 90° turn at the free end of a reinforcing bar to provide anchorage in concrete. For stirrups and column ties only, turns of either 90° or 135° are used.
HOOK ON and/or HOOK OFF—The act of placing or removing chokers or slings on or off a bundle of reinforcing bars and connecting or disconnecting the crane hook.
HORIZONTALS—Reinforcing bars running horizontally.
HONEYCOMB—Voids left in concrete due to loss or shortage of mortar or inadequate consolidation of the concrete.
INDIVIDUAL HIGH CHAIRS—Bar support used under a support bar, to provide support for top reinforcing bars in slabs, joists or beams; also used to support upper mats of bars in slabs without support bars.
INSERTS—Devices embedded in concrete to receive a bolt or screw to support shelf angles and machinery.
INSPECTOR—A person who examines the Work in progress at the jobsite to see that it conforms to the project drawings and project specifications.
INTEGRAL—Elements which act together as a unit, such as concrete joists and top slab. Reinforced concrete members may be made integral by bond, dowels, or being cast in one piece.
INTEGRALLY-CAST—Elements (such as reinforced concrete joists and top slab) cast in one piece. See MONOLITHIC.
IRONWORKERS—Workers who handle and place steel and ornamental iron, including reinforcing steel and bar supports. Also, in the Metropolitan Area of New York City, depending on local union jurisdiction, these workers are called LATHERS. Colloquial terms frequently used include rod-setter, rodbuster; bar-setter, and bar placer.
JACK ROD—Plain rod, usually 7/8 or 1 inch in diameter, with square-cut or threaded ends to support sliding forms in conjunction with a jack. In some cases, these jack rods are also used as a portion of the vertical reinforcement required.
JACK ROD SLEEVE—Piece of pipe which joins two jack rods for an end-to-end butt connection.
JOINTED REINFORCED CONCRETE PAVEMENT—A reinforced pavement with transverse joints typically spaced at 30 feet or more.
JOIST—T-shaped beam used in a parallel series in reinforced concrete joist floor construction.
JOIST CHAIRS—Bar supports which hold and space the two reinforcing bars in the bottom of a joist.
JOIST SCHEDULE—Table on a placing drawing giving the quantity and mark of the joists, the quantity, size, length, bending details of reinforcing bars and usually the quantity of joist chairs in each joist.
KEYS—Slotted joints in concrete, such as tongue and groove.
ksi—Abbreviation of kips (1,000 pounds) per square inch, used in measuring load or stress.
LAP SPLICE—The overlapping of two reinforcing bars by lap splicing them side by side (in contact or non-contact); similarly the side and end overlap of sheets or rolls of welded wire reinforcement. Also, the length of overlap of two bars. Also referred to as “lap”.
LAP-SPLICE CONNECTOR SYSTEMS—Proprietary or patented prefabricated plastic or metal boxes or strips of foam acting as keyway forms and containing prefabricated anchorage and lap splice reinforcement. The lap splice reinforcement is field-straightened with a pipe and/or hickey when the keyway form is exposed for the next pour.
LIFT—Units of reinforcing bars tied together for shop or field convenience. Lifts are classified in two categories: (1) Shop lifts and (2) Field lifts. Shop lifts are units of reinforcing bars loaded for shipment to the jobsite. Field lifts are units of reinforcing bars required for field handling by the Contractor. A field lift may consist of single bundles or two or more smaller bundles tied together. A shop lift may consist of one or more bundles, the same as field lifts or consist of two or more field lifts. Straight and bent bars are not combined in the same lift. Maximum weight of a lift is dependent on regional practices and site conditions. See BUNDLE OF BARS. The term LIFT also describes the concrete placed between two consecutive horizontal construction joints, particularly when formwork is reused and lifted.
LIFT SLAB—Floor construction in which slabs are cast directly on one another. Each slab is lifted into final position by jacks on top of the columns. Floors are secured at each floor level by column brackets or collars.
LIGHT BENDING—All #3 [#10] bars, all stirrups and ties, and all bars #4 through #18 [#13 through #57], which are bent at more than six points in one plane, or reinforcing bars which are bent in more than one plane (unless “Special Bending”), all one plane radius bending with more than one radius in any bar (three maximum) or a combination of radius and other type bending in one plane (radius bending being defined as all bends having a radius of 12 inches or more to inside of bar).
LINTEL—Beam supporting the wall above a window or door opening.
LONGITUDINAL BAR—Any reinforcing bar placed in the long direction of the member.
LOW-ALLOY STEEL REINFORCING BARS—Reinforcing bars rolled from low-alloy steel billets.
MARK OUT—Indicating with keel (crayon) marks on the forms, the location of each reinforcing bar; usually done by the Foreman from information derived from the placing drawings, prior to starting actual placing operations in an area.
MARKS—A series of letters, numbers or a combination of both used to designate (a) the parts of a structure or (b) the identity of a bent reinforcing bar.
MAT—A large footing or foundation slab used to support an entire structure. The term MAT also describes a grid of reinforcing bars.
MECHANICAL SPLICE—The complete assembly of an end-bearing sleeve, a coupler, or a coupling sleeve, and possibly additional materials or parts to accomplish the splicing of reinforcing bars.
MECHANICAL DRAWINGS—Drawings which show piping for water, sanitary, gas and drains; heating, ventilating and air conditioning ducts and equipment, and other mechanical equipment.
MESH—See WELDED WIRE REINFORCEMENT.
METAL FORMS—Used to provide the forms for joist floor construction. Also known as PANS.
METAL LATHER—A worker who installs furring and metal lath, places inserts in concrete for support of ceilings; and in the Metropolitan Area of New York City, fabricates and places bar supports and reinforcing steel, which is delivered to the jobsite in straight lengths.
MISCELLANEOUS IRON—Steel items such as lintel angles, inserts, plates, form braces, spreaders and other structural shapes attached to or embedded in reinforced concrete.
MONOLITHIC—Concrete cast in one operation.
MPa—Abbreviation of the metric unit megapascals, used in measuring load or stress. Approximately 6.9 megapascals equals 1 ksi.
NEAR FACE (OF A WALL)—Face nearest the viewer and may be inside or outside, depending on whether one is inside looking out or outside looking in.
NON-CONTACT SPLICE—A means of splicing reinforcing bars by lap splicing not in direct contact. See LAP SPLICE.
NOMINAL DIAMETER—The diameter of a plain round bar of the same weight per linear foot as a deformed reinforcing bar.
OFFSET BEND—Any bend in a reinforcing bar that displaces the center line of a section of the bar to a position parallel to the original bar, in which the displacement is relatively small; commonly applied to column vertical bars. Also known as “dog-leg.”
ONE-WAY SLABS-A slab which presumably bends in only one direction.
OSHA—Occupational Safety & Health Administration.
OWNER—The corporation, association, partnership, individual, or public body or authority which the Contractor enters into agreement with and for whom the Work is provided.
PAD—A footing; sometimes a block of concrete to support machinery.
PANS—Metal forms for one-way reinforced concrete joists (one-way pans) and for two-way (waffle slab) concrete joists (dome pans).
PARAPET—Extension of the main walls above the roof level, for architectural appearance.
PEDESTAL—Short pier used as a base for a column.
PIER—A short column used as a foundation member in construction. Also, a large column or wall type bridge support.
PILASTER—Column partially or completely embedded in a wall, or a portion of a wall enlarged to serve as a column.
PILE—A concrete, steel, or wood member driven into the ground to support a load.
PILE CAP—A structural member placed on the tops of piles and used to distribute loads from the structure to the piles.
PITCH—Center-to-center spacing between turns of a spiral.
PLACING DRAWINGS—Detailed drawings which give the quantity, size, location, spacing of the reinforcing bars, and all other information required by the Ironworker.
PLAIN CONCRETE—Structural concrete with no reinforcement or with less reinforcement than the minimum amount specified in the ACI Building Code.
PLAN VIEW—Top view as of any floor, roof, or foundation of a structure.
POLE DERRICK—Small portable derrick, guyed by ropes, having a hand winch on which a cable is mounted, for raising moderately heavy objects.
POST-TENSIONING—A method of prestressing reinforced concrete when tendons are tensioned after concrete has reached a specified strength.
PRECAST CONCRETE—Reinforced concrete cast elsewhere than its final position in the structure. Usually precast concrete consists of individual members such as columns, wall panels, beams or joists erected and connected to form the structural frame.
PRECAST PILE—A reinforced concrete pile manufactured in a casting plant or at the jobsite and driven into place by a pile hammer.
PRESTRESSED CONCRETE—Reinforced concrete in which the reinforcing steel is stretched and anchored to compress the concrete.
PROJECT DRAWINGS—The drawings which, along with the Project Specifications, completely describe the construction of the Work required or referred to in the Contract Documents. Examples include Placing Drawings and Structural Drawings.
PROJECT SPECIFICATIONS—The written documents which describe the requirements for a project in accordance with the various criteria established by the Owner. psi—Abbreviation of pounds per square inch used in measuring load, pressure, or stress.
PUSHER—Common expression for Ironworker Foreman.
RACKS—Metal or wooden supports for that portion of a reinforcing bar that extends beyond a construction joint and is not already supported by existing formwork or conventional tying to adjacent bars.
RADIUS BENT—Reinforcing bars bent to a radius larger than that specified for standard hooks; a bar curved to fit into circular walls, as the horizontal bars in a silo.
RAIL-STEEL REINFORCING BARS—Deformed reinforcing bars rolled from selected used railroad rails.
REBAR—Abbreviated term for reinforcing bar.
REED CLIPS—Light wire sections fastened to structural steel, to hold fireproofing to faces of structural steel beam and column flanges.
REGLET—A long, narrow formed slot in concrete to receive flashing or to serve as anchorage.
REINFORCED CONCRETE—Concrete containing reinforcing steel positioned so that the two materials act together for increased strength.
REINFORCEMENT—Steel bars or wires embedded in concrete and located in such a manner that the steel and the concrete act together in resisting loads.
RETAINING WALL—Wall reinforced to hold or retain soil, water, grain, coal, or sand.
RIGGER—Mechanic whose function is to brace, guy, and arrange for hoisting materials.
RUNWAY—Decking over an area of concrete placement, usually of movable panels and supports, on which buggies of concrete travel to points of placement.
SAND PLATE—A flat plate attached to the legs of a bar support for use on soil.
SCAFFOLDING—A temporary structure for the support of deck forms, runways, or workers.
SCALE—Reduction of size to which drawings are made (as 1/8 inch = 1 foot).
SCHEDULE—Table on placing drawings (or elsewhere) to give size, shape, and arrangement of similar items. See BEAM SCHEDULE, COLUMN SCHEDULE, JOIST SCHEDULE, and SLAB SCHEDULE.
SCREED—A template to guide finishers in leveling off the top of fresh concrete. Screeding is the operation of rough leveling.
SCREED CHAIRS—Supports to fix the depth of slab and to hold guides for leveling off concrete.
SECTION—Cut away view through a general plan or elevation view to explain details.
SHEAR—To cut off as by two equal opposed forces. SHEARHEAD—Assembled unit in the top of the columns of flat slab or flat plate construction to transmit loads from slab to column.
SHEAR REINFORCEMENT—Reinforcement designed to resist shearing forces; usually; consisting of stirrups bent and located as required.
SHEAR WALL—A wall designed to resist forces resulting from wind, blast or earthquake.
SHELF ANGLES—Structural angles with holes or slots in one leg for bolting to the concrete to support brick work, stone, or terra cotta.
SIMPLE BEAM—Beam supported at each end (two points) and not continuous.
SKEWED—Placed at an angle other than 90°.
SLAB—Flat section of floor or roof either on the ground or supported by beams or walls.
SLAB BOLSTER—Continuous bar support used to support bottom slab bars.
SLAB ON GROUND—A type of foundation with a concrete floor which is placed directly on the soil. The edge of the slab is usually thicker and acts as the footing for the walls. Sometimes called a “slab on grade”.
SLAB SCHEDULE—Table on a placing drawing giving the quantity and mark of the slabs; the number of pieces, size, length and bending details of the reinforcement in each slab.
SLEEVE—A tube which encloses a bar, dowel, or anchor rod.
SLING—Short lengths of wire, nylon, or Kevlar rope, with a spliced eye at each end or a spliced eye at one end and a hook at the other, used to encircle a bundle of bars for hoisting purposes.
SLIP FORM—System of formwork for concrete which permits continuous casting. Vertical slip forms are used in buildings and tanks and horizontal slip forms are used in paving.
SOFFIT—The bottom of a slab, beam, joist or girder.
SORTING—Opening up the bundles of reinforcing bars after unloading, so that all items are readily accessible.
SPALLING—The development of concrete spalls or fragments, usually in the shape of flakes, detached from a larger mass of concrete by a blow, action of weather, pressure or by expansion within the larger mass.
SPAN—The horizontal distance between supports of a structural member such as a beam, girder, slab or joist; distance between piers or abutments of a bridge.
SPANDREL BEAMS—Perimeter or edge beams; a beam in an exterior wall.
SPECIAL BENDING—All bending to special tolerances, all radius bending in more than one plane, all multiple plane bending containing one or more radius bends, and all bending for precast units.
SPECS—A contracted term for “project specifications”; the directions issued by an Architect or Engineer to establish general conditions, standards and detailed instructions which are used with the project drawings.
SPIRAL—A continuously coiled reinforcing bar or wire.
SPIRAL COLUMN—A column in which the vertical reinforcing bars are enclosed within a spiral. See SPIRAL.
SPIRAL SPACERS—Usually made of channels or angles, punched to form hooks, which are bent over the coiled spiral to maintain it to a definite pitch.
SPLICE—Connection of one reinforcing bar to another by lap splices (in contact or non-contact), mechanical splices, or welded splices; the lap between sheets or rolls of welded wire reinforcement.
SPREADER BAR—A steel beam suspended from a crane, having two or more hooks or shackles to which slings are attached to eliminate the possibility of bending reinforcing bars in a bundle due to handling. Sometimes called a “strong back.”
SPREAD FOOTINGS—Footings which support one or more columns or piers or a wall by bearing on earth or rock. Sometimes a simple mat footing is called a spread footing.
STAGGERED SPLICES—Splices in reinforcing bars which are not made at the same plane.
STANDEE—A term used in some regions of the country to designate a special bar bent to a U-shape with 90° bent legs extending in opposite directions at right angles to the U-bend. It is used as a high chair resting on a lower mat of reinforcing bars and supporting an upper mat. Sometimes called a “fabricated high chair”.
STEM BARS—Reinforcing bars used in the wall section of a cantilever retaining wall or in the webs of a box girder. When a cantilever retaining wall and its footing are considered as an integral unit, the wall is often referred to as the stem of the unit.
STIRRUPS—Reinforcing bars or welded wire reinforcement used in beams and girders for shear reinforcement; typically bent into a U-shape or box-shape and placed perpendicular to the longitudinal reinforcing bars.
STORY POLE—Piece of wood or bar marked with the story height and vertical distances for spacing horizontal reinforcing bars.
STRIPS—Bands of reinforcing bars in flat slab or flat plate construction. The column strip is a quarter-panel wide each side of the column centerline and runs either way of the structure, from column to column. The middle strip is half a panel in width, filling in between column strips, and runs parallel to the column strips to fill in the center part of a panel.
STRUCTURAL DRAWINGS—Drawings which show all framing plans, sections, details and elevations required to construct the structure. For reinforced concrete structures, they include the sizes and general arrangement of all reinforcement from which the Fabricator prepares placing drawings.
STRUT—Short column or compression brace.
SUBCONTRACTOR—A Contractor who is under contract to the General Contractor for completion of a portion of the Work for which the General Contractor is responsible.
SUPERINTENDENT—General Contractor’s representative at the jobsite who is responsible for continuous field supervision, coordination, and completion of the Work.
SUPERSTRUCTURE—Frame of the structure, usually above grade. Portion of a bridge above piers and abutments.
SUBGRADE—The soil supporting a structure or pavement.
SUPPORT BARS—Rest on individual high chairs or bar chairs to support top reinforcing bars in slabs or joists, respectively.
T-BEAM—Beam which has a T-shaped cross-section.
TEMPERATURE BARS—Reinforcing bars distributed throughout the concrete to minimize cracks due to temperature changes and concrete shrinkage.
TEMPLATE—A rigid device to locate and hold dowels, to lay out bolt holes or inserts. See DOWEL TEMPLATE.
TENDON—A steel element such as strand, wire, bar, or rod, or a bundle of such elements, used to impart prestress to a reinforced concrete member.
TENSILE STRENGTH—Maximum stress a material is capable of resisting under axial tension loading.
TIE—Reinforcing bars bent to a circular, or to a box-shape and used to hold vertical longitudinal reinforcing bars together in columns and beams.
TIE BARS—Reinforcing bars at right angles and tied to main reinforcement to keep it in place; bars extending across a construction joint.
TIE WIRE—Wire (generally No. 16, No. 15, or No. 14 gauge) used to secure intersections of reinforcing bars for the purpose of holding them in place until concreting is completed.
TILT-UP—A method of concrete construction in which the walls are cast horizontally at a location adjacent to their eventual position, and lifted into place after removal of forms.
TOLERANCE—Allowable variation from a given dimension, quantity, or position.
TRANSVERSE—At right angles to the long direction of the member (crosswise). Also referred to as “lateral.”
TRUSS BARS—Reinforcing bars bent up to act as both top and bottom reinforcement.
TWO-WAY FLAT SLAB—See FLAT SLAB.
UPTURNED BEAM—Reinforced concrete beam which extends above the slab or structure it is supporting.
VERTICAL BAR—Any reinforcing bar used in an upright or vertical position.
VIBRATOR—An oscillating machine used to consolidate fresh concrete to eliminate voids or “honeycomb” before concrete hardens. See HONEYCOMB.
VOIDED SLAB—The concept of a voided flat plate centers on removing “concrete” from the middle of the slab where it is structurally inefficient; reducing the dead load by as much as 35% and allowing a larger clear span with an economical slab thickness.
WAFFLE SLAB—A two-way reinforced concrete joist floor with ribs running in both directions. (Named after the waffle-like appearance of the underside of the finished floor).
WALES—Braces to two or more form panels, palings, or studs, usually horizontal. Often incorrectly called “walers.”
WALL—A vertical structural member which encloses, divides, supports or protects a building or room.
WALL BEARING STRUCTURE—One with the slabs (i.e., the floors or roofs) supported on walls, generally of masonry, eliminating columns and some of the beams.
WALL SPREADER—An accessory, usually fabricated from a reinforcing bar to a “Z” or “U” shape, used to separate and hold apart two faces or curtains of reinforcement in a wall.
WEEP HOLE—Drainage opening in a wall.
WELDED SPLICES—A means of joining two reinforcing bars by electric arc welding. Bars may be lapped, butted, or joined with splice plates or angles.
WELDED WIRE REINFORCEMENT—Wire reinforcement manufactured by means of welding the intersecting wires, used for reinforcement in slabs, slabs on grade, and highway pavements. Also known as welded wire fabric.
WINCH—Mechanical lifting device attached to derricks on which cable is wound up by means of a crank and locked in position by a ratchet.
WING WALL—Retaining wall at end of a bridge or culvert to retain the earth.
WORK—The entire project (or separate parts) which is required to be completed under the Contract Documents. Work is the result of performing services, furnishing labor, and supplying and incorporating materials and equipment into the construction, all as required by the Contract Documents.
WRAPPING—Reinforcing bars or welded wire reinforcement surrounding a structural steel column or beam to reinforce concrete or plaster fireproofing.
YIELD STRENGTH—The load limit to which reinforcing steel will stretch and return to its original length.
ZINC COATING—A zinc coating applied to reinforcing steel by dipping in a molten bath of zinc to prevent corrosion. Also known as GALVANIZING.