Concrete and Steel Construction Materials and Systems

Comprehensive practice vocabulary flashcards covering concrete ingredients, clinker chemistry, admixtures, precast and sitecast concrete systems, prestressing, structural steel detailing, and light-gauge steel construction.

Portland cement

The most common cement, patented by Joseph Aspdin in $1824$ (ASTM C150).

ASTM C150

The standard specification governing Portland cement types that vary in set time, strength, color, water demand, and admixture compatibility.

Cement ingredients

Limestone (calcium), sand (silica), clay (aluminum), and iron (mill scale), plus small amounts of sulfur, alkali, and magnesium.

C3S

A cement clinker compound primarily responsible for $7$-day strength.

C2S

A cement clinker compound primarily responsible for $28$-day strength.

C3A

A cement clinker compound that generates early strength and whose set rate is controlled by adding gypsum.

C4AF

A cement clinker compound that acts as a flux and provides color.

Cement kiln

A rotary furnace operating at $2,700^\bot\circ\text{F}$ that transforms heated raw powder into clinker.

Substitute Cementitious Materials (SCMs)

Industrial byproducts used to replace a portion of Portland cement in a concrete mix (such as replacing $15\%$ of cement with fly ash).

Fly ash

A coal-burning power plant byproduct (ASTM C618) that improves workability, pumpability, strength, and durability while lowering mix cost.

Slag cement

A steel industry byproduct (ASTM C989) that improves workability, strength, and durability, alters concrete color, and is useful in mass concrete.

Silica fume

A byproduct of silicon metal or ferrosilicon alloy production (ASTM C1240) that increases strength, reduces permeability, and improves durability.

Fine aggregate

Clean, washed sand utilized in concrete.

Coarse aggregate

Gravel, crushed granite, or crushed limestone added to concrete.

Air entrainment

The generation of stable microscopic spherical bubbles ($0.003\text{ to }0.05\,\text{in}$, spaced $0.008\,\text{in}$ or less apart) to provide freeze-thaw and deicing salt resistance, improve workability with less water, and reduce bleeding and segregation.

Concrete curing protection

Techniques including windbreaks, fogging sprayers, a wet subgrade, immediate curing, and insulating blankets designed to prevent scaling, popouts, and mortar flaking caused by rapid drying or freezing.

Cast-in-place concrete

Concrete poured and cured in its final permanent position on the construction site (sitecast) inside formwork.

Key (footing)

A groove formed along the top of a footing to mechanically lock the wall to the footing after placement.

Steel reinforcement

Steel bars or mesh embedded in concrete to carry tension forces, protected against corrosion by the alkaline concrete paste.

Rebar numbering (US)

A bar designation system where the number represents the diameter in eighths of an inch (e.g., #4 = $1/2\,\text{in}$).

Metric rebar (#M)

Steel reinforcing bars designated by '#M,' corresponding roughly to their diameter in millimeters.

Deformations (rebar)

Surface ridges rolled onto steel reinforcement bars to mechanically bond with and grip the surrounding concrete.

WWR / WWF / WWM

Welded wire reinforcement, fabric, or mesh formed by a grid of prefabricated welded steel wires.

Precast concrete frame

A structural skeleton constructed from concrete components cast and cured off-site in a factory and assembled on site.

Solid slab

A precast concrete member formed as a flat, completely solid slab.

Hollow core slabs

Precast concrete floor or roof slabs manufactured with continuous longitudinal round voids to reduce dead load.

Double-tee

A standard precast concrete member configured with a broad top flange supported by two downward vertical stems.

Single-tee

A standard precast concrete member consisting of a flat top flange supported by one central downward vertical stem.

Sonotube

Cardboard cylindrical formwork used to pour round cast-in-place concrete columns.

Symons pans

Reusable prefabricated modular panels used to assemble concrete wall formwork.

Formwork

A temporary mold assembly that supports and confines wet concrete until it hardens, commonly composed of plywood sheathing, studs, walers, form ties, and bracing.

Studs (formwork)

Vertical framing members that directly support and stiffen the plywood sheathing in wall formwork.

Walers

Horizontal members that align and brace formwork studs while transferring fluid concrete lateral forces to form ties.

Form ties

Metal tension rods that hold opposing formwork faces together under the pressure of wet concrete and remain inside the wall after stripping.

Consolidating wet concrete

The process of vibrating fresh concrete during placement to eliminate entrapped air pockets and ensure complete encapsulation of rebar.

Insulated Concrete Forms (ICFs)

Hollow interlocking foam blocks that act as formwork for wet concrete and remain permanently in place as thermal insulation.

Precast concrete wall panels

Exterior wall assemblies cast and cured off-site, manufactured as solid, composite (insulated), or ribbed profiles.

Composite (insulated) wall panel

A precast sandwich wall panel consisting of a layer of insulation positioned between two concrete wythes.

Ribbed wall panel

A precast concrete wall panel cast with vertical stiffening ribs, resembling a double-tee oriented on its side.

Tilt-up construction

A method of construction where reinforced concrete wall panels are cast flat on site slabs and tilted upright with a crane.

Prestressing

The technique of introducing internal compressive stresses to concrete using tensioned high-strength steel strands to counteract bending and tensile loads.

Pretensioning

A method of prestressing where high-strength steel strands are stressed prior to pouring concrete and released once the concrete cures.

Post-tensioning

A method of prestressing where steel tendons ($7$-wire strand, grade $270$) enclosed in greased sheathing are stressed with hydraulic jacks after the concrete hardens.

Chairs and bolsters

Small plastic or metal supports that keep rebar and post-tensioning tendons at their proper design height above formwork.

Ferrous metals

Metals that contain iron, including cast iron, wrought iron, and structural steel.

Non-ferrous metals

Metals that contain no iron, including aluminum, copper, zinc, and lead.

Alloy

A metallic material formed by combining different metals to modify their mechanical and chemical properties.

Cast iron

A brittle ferrous metal characterized by high carbon content and impurities.

Wrought iron

A malleable ferrous metal shaped by mechanical hammering.

Steel (composition)

A ferrous alloy containing approximately $0.3\%$ carbon.

Stainless steel

A corrosion-resistant ferrous alloy formulated with over $10\%$ chromium and nickel.

Bronze

A non-ferrous metal alloy composed of copper and tin.

Brass

A non-ferrous metal alloy composed of copper and zinc.

Galvanic corrosion

An electrochemical reaction occurring when dissimilar metals contact each other, causing the more anodic metal (such as zinc or aluminum) to corrode.

W14x30

A structural steel designation indicating a wide-flange shape (W) with a nominal depth of $14\,\text{in}$ and a weight of $30\,\text{lb/ft}$.

Rivets

Hot metal pins hammered into place to join structural steel members, predominantly used in historic framing.

Structural welding

The process of fusing structural steel components together using intense heat and filler metal.

Structural bolts

High-strength threaded fasteners used to mechanically connect structural steel components in the field.

Steel frame seismic design

The incorporation of welded moment connections and braced frames engineered to bend and dissipate earthquake energy.

Steel frame fire protection

Protective coverings such as sprayed fireproofing, intumescent paint, gypsum board, or concrete applied to steel members to prevent structural failure at high temperatures.

Open web steel joists (OWSJ)

Lightweight, factory-fabricated steel trusses composed of parallel chords and zigzag web bars used for floor and roof support.

Form decking

Corrugated steel floor decking that supports wet concrete and acts strictly as a stay-in-place formwork skin.

Composite decking

Corrugated steel deck with embossed patterns that bonds with cured concrete to carry floor loads compositely.

Light-gauge steel construction

Framing systems constructed from cold-formed thin steel sheets prepunched for utility distribution, structurally analogous to wood light-frame construction.

Cee-joist

A C-shaped cold-formed light-gauge steel framing member used for floor joists and wall studs.

Joist closure

A cold-formed light-gauge steel track piece mounted to close off the perimeter edges of light-gauge joists.

Gauge (metal thickness)

A standard measurement of sheet metal thickness where an inversely smaller gauge number corresponds to a thicker metal section.

Web stiffener

A small steel piece attached directly to the web of a light-gauge joist at points of concentrated load to prevent web crushing or buckling.