Concrete and paving glossary - F

A | B | C | D | E | F | G | H | I | J | K | L | M
N | O | P | Q | R | S | T | U | V | W | XYZ

F numbers

The specification of the degree of flatness that a slab or floor must have. The degree of flatness of a concrete floor is extremely critical for warehouse or manufacturing plant floors where specialized materials handling equipment may be guided by wires under the concrete floor.

Face forms

Concrete forms that are used to create a desired curb profile. They attach to the curb and gutter form set up by hooking to the clips of the division plate. Face forms are designed based on the amount of batter specified. See batter, curb and gutter combination, and curb and gutter forms.

Faced concrete

To finish the front and all vertical sides of a concrete porch, step(s), or patio. Normally the "face" is broom finished. See broom finish.

Fair face concrete

A concrete surface that, on completion of the forming process, requires no additional (concrete) treatment other than curing. See architectural concrete and curing.

False set

The rapid development of rigidity in a mixed Portland cement paste, mortar, or concrete without the evolution of much heat. This rigidity can be dispelled and plasticity regained by further mixing without the addition of water. Premature stiffening, and rubber set are terms referring to the same phenomenon, but false set is the preferred term. See flash set, Portland cement, and set.

Fat

Material accumulating on a trowel during smoothing. Fat is used to fill in small imperfections. See trowel and troweling.

Fat mix / rich mix

A mortar or concrete mix with a relatively high cement content. Fat mix is more easily spread and worked than a mix with the minimum amount of cement required for strength. See cement and cement mixture.

Fiber reinforced concrete

A variant of concrete that is produced by adding fibers made of stainless steel, glass or carbon to the mixture. See reinforced concrete.

Fibrous admixture

Special fibrous substances of glass, steel, or polypropylene that are mixed into concrete to act as a reinforcement against plastic shrinkage cracking.

Filler forms

Concrete forming accessories used to connect two metal forms when a gap between the forms exists. Typically, filler forms have a channel that slides over the top rail of the forms to be connected. See straight forms.

Fine aggregate

Aggregate passing the 1/2" sieve and almost entirely passing the No. 4 sieve and predominantly retained on the No. 200 sieve.

Fineness modulus

An index of fineness or coarseness of an aggregate sample. An empirical factor determined by adding total percentages of an aggregate sample retained on each of a specified series of sieves, and dividing the sum by 100. Note: US Standard sieve sizes are used: No. 100, No.50, No. 30, No. 16, No. 8, and No. 4, and 3/8 inch, 3/4 inch, 1 inch, 2 inch, 3 inch, and 6 inch.

Finishing

Leveling, smoothing, compacting, and otherwise treating surfaces of fresh or recently placed concrete or mortar to produce the desired appearance and service. See also float.

Fixed nose form

A metal concrete pouring form with a fixed nose piece to allow it to interlock with the rear section of another form creating a solid interconnection. Fixed nose forms must be removed in order or reverse order after a pour due to their interlocking nature. See sliding nose forms.

Flash set

The rapid development of rigidity in a mixed Portland cement paste, mortar or concrete usually with the evolution of considerable heat, which rigidity cannot be dispelled nor can the plasticity be regained by further mixing without addition of water also referred to as quick set or grab set. See false set.

Flat stakes

Flat metal stakes used to secure wooden forms in sandy or loose soils prior to concrete placement. See curb and gutter forms, form pins, flatwork forms, and nail stakes.

Flatwork

Common word for concrete floors, driveways, basements, and sidewalks.

Flatwork forms

Metal or wood forms used in concrete flatwork placement. These forms are typically used for edge forming, sidewalks, driveways, footings, industrial slabs, foundations, patios, general flatwork, and in combination with our curb and gutter accessories, plus concrete curb and gutter work. See curb and gutter forms, flexible forms, and straight forms.

Flexible forms

Metal forms used forming radius shapes such as islands, serpentine sidewalks, curved curbs, parking lot turnouts, and similar applications. They are made from spring steel and are typically 10 feet long with stake pockets riveted onto the form every 18". They range in height form 4" to 12". The same as radius forms. See spring steel.

Flexible filler forms

A flatwork form accessory used to fill in spans of less than 10' where radius forming is required. These forms are sometimes referred to as rehab forms. See flatwork forms, flexible forms, and straight forms.

Float

A tool (not a darby), usually of wood, aluminum, magnesium, rubber, or sponge, used in concrete or tile finishing operations to impart a relatively even but still open texture to an unformed fresh concrete surface. See darby and trowel.

Float coat

A finish coat of cement paste applied with a float. See float.

Floating

The next-to-last stage in concrete work, when you smooth off the job and bring water to the surface by using a hand float or bull float. The operation of finishing a fresh concrete or mortar surface by use of a float, preceding troweling when that is the final finish. See troweling, float, and float coat.

Floating wall

A non-bearing wall built on a concrete floor. It is constructed so that the bottom two horizontal plates can compress or pull apart if the concrete floor moves up or down. A floating wall is normally built on basements and garage slabs.

Flow-line

The section of a pitch-in curb where water flows in a parallel direction. See pitch-in.

Fly ash

A byproduct produced by coal-burning power plants that contains aluminosilicate and small amounts of lime. When combined with lime in a hydrothermal (using hot water under pressure) process, cement can be produced. It is a concrete admixture. See admixture.

Footing

The widened portion of the foundation or a structure that spreads and transmits the load from the building or foundation directly to, and across a broader area of, the soil. A continuous 8" or 10" thick concrete pad installed before that supports the foundation wall or monopost.

Form

A temporary erected structure or mold for the support and containment of concrete during placement and while it is setting and gaining sufficient strength to be self-supporting.

See corner forms, formwork, filler forms, flexible forms, keyway forms, placement, radius forms, reversible forms, straight forms, slurry, tilt-up forms, tilt-up reversible forms, and transition forms.

Form hanger

A device used to support formwork from a structural framework. The dead load of forms, weight of concrete, and construction and impact must be supported. See formwork.

Form pins

Solid steel pins made from either cold-rolled and hot-rolled steel used for securing metal flatwork forms to the ground by driving the pins through wedge pockets and for attaching screed bar holder clamps used flatwork finishing.

Pins are typically 1/2" or 7/8" in diameter and vary in length from 12" to 48" or more depending on the project requirements.

See cold-rolled solid steel form pins, flat stakes, flatwork forms, flexible forms, hot-rolled solid steel form pins, nail stakes, and screed bar holder.

Form rail

The top edge of a straight form that runs the length of the form and is typically 2 inches wide for most standard forms. Often, form rails are used as guides and supports for screeding. See screeding and straight forms.

Form release agent or compound

Material used to prevent bonding of concrete to a surface, such as to forms. See bond breaker, stripping agent, and release agent.

Form scabbing

The inadvertent removal of the surface of concrete as a result of adhesion to the form.

Form stakes

See form pins.

Forming

The use of metal or wood forms to create the proper placement of concrete. The forming process channels the concrete into the desired shape and thickness.

See corner forms, filler forms, flexible forms, keyway forms, placement, radius forms, reversible forms, straight forms, slurry, tilt-up forms, tilt-up reversible forms, and transition forms.

Formwork

Temporary structures or forms made of wood, metal, or plastic used in the placing of concrete to ensure the slurry is shaped to its desired final form. Formwork must be strong enough to support the considerable weight and pressure of wet concrete without deflection.

See corner forms, filler forms, flexible forms, keyway forms, placement, radius forms, reversible forms, straight forms, slurry, tilt-up forms, tilt-up reversible forms, and transition forms.

Foundation

The entire masonry substructure below the first floor or frame of a building, including the footing upon which the building rests.

Foundation form sets

Custom made sets of metal concrete forms used for houses, garage, car port, strip mall, warehouse floors, and other structures which require slab on grade foundations. See custom forms and foundation.

Foundation ties

Metal wires that hold the foundation wall panels and rebar in place during the concrete pour.

Foundation waterproofing

A high-quality below-grade moisture protection. It is used for below-grade exterior concrete and masonry wall damp-proofing to seal out moisture and prevent corrosion. Foundation waterproofing normally looks like black tar.

Frame

The setting up of formwork. See formwork.

A | B | C | D | E | F | G | H | I | J | K | L | M
N | O | P | Q | R | S | T | U | V | W | XYZ