M and M Quiz 3

Portland cement

the most widely used cement type globally and serves as the essential ingredient that gives concrete its strength and durability. It was patented in 1824 by Joseph Aspdin, who named it after Portland stone due to its similar appearance when hardened.

Raw materials: Primarily limestone (calcium source) plus clay, shale, or similar materials providing silica, alumina, and iron.

Cement & Concrete

a composite construction material made by mixing cement, water, and aggregates, which hardens into a strong, durable solid.

Cement ingredients

L imestone

I ron

S and
A luminum

S ulfur
A lkali
M agnesium

Cement production process

production involves quarrying raw materials like limestone and clay, grinding them into raw meal, heating the mix in a preheater and rotary kiln to form clinker at about 2,700°F, cooling the clinker, and finally grinding it with gypsum before packaging.

Substitute Cementitious Materials (SCM's):

Fly Ash

Slag Cement

Silica fume

Fly ash

-Byproduct of coal burning power plants

-Workability Pumpability Strength Durability Cost Environment

Slag cement

-Byproduct of the steel industry

-workability, strength, durability, cost, color (tan), mass concrete

Silica fume

-byproduct of producing silicon metal or ferrosilicon alloys

-strength, permeability, durability

Aggregate types and why aggregate is used in concrete

fine aggregate- Particles passing a 4.75 mm (No. 4 sieve) — typically natural sand, manufactured sand, or crushed stone sand.
Functions: Fills voids between coarse particles, improves workability, adds cohesion

Coarse aggregate- Particles retained on a 4.75 mm sieve — gravel, crushed limestone, granite, basalt, etc., usually 5 mm to 150 mm (commonly 19–25 mm).
Functions: Provides main load‑bearing framework, reduces shrinkage, improves durability.

Packing Density

Need enough cementitious paste to fill all the void and additional paste for finish ability

Lower shrinkage • Reduced heat of hydration • Improved durability • Lower cost

Cement admixtures and some functions they serve

chemical or mineral additives introduced into concrete during or before mixing to modify its fresh or hardened properties, improving workability, strength, durability, and setting time

Air Entrainment • Water Reducers • Set Accelerators • Set Retarders • Specialty • Shrinkage Reducers • Corrosion Inhibitors

Air entrainment

1. Durability air in concrete?

• Freeze/thaw resistance–

• Salts

2. workability

• less water needed

3.reduces bleeding and segregation

4. types of air

• entrapped (large, Irregular shape)

• entrained (small, spherical shape, spacing)

Controlling temperature and surface water conditions as concrete sets

ACCELERATORS • Decreases the set time of the concrete • Primarily used during cooler weather conditions

HYDRATION STABILIZERS • Increases the set time of the concrete • Primarily used during warmer weather conditions

scaling

Peeling of the concrete surface as a result of freezing and thawing.

pop outs

A cavity at the surface of concrete as a result of an aggregate particle that expands and fractures.

mortar flaking

Dislodging of surface concrete directly above coarse aggregate particles.

Cast-in-place concrete

Foo ng is poured first (typically) with a key and rebar extending up. Then formwork and rebar is placed, and wall is poured.

Key (such as in a footing)

A groove or notch cut into the top or edge of a footing to receive the next concrete pour or a wall, creating a mechanical interlock

Steel reinforcement-Reasons for use

Steel and concrete are mechanically & chemically compatible: Concrete & steel change nearly the same rate due to temperature. The alkaline chemistry of concrete protects steel from rusting. Concrete bonds to steel

Rebar numbering

In US: # = 1/8’s of inch diameter; Rest of the world: hard metric “#M” roughly mm dia.

WWR/WWF/WWM

welded wire mesh: grid of wires

Precast Concrete Frame and its advantages & disadvantages

beams columns and walls are manufactured off site and brought to the construction site

Pros-speed, quality control, natural bend, durability, less waste

Cons-transportation costs, joint work, higher inital investment

Precast beam shapes

Solid Slab

Hollow Core slabs

Double-Tee

Single-Tee

solid slab

rectangular cast with constant width and depth with reinforcements

hollow core slabs

a constant rectangular cross‑section containing multiple longitudinal hollow voids that run the full length of the element

double-tee

member shaped like two capital “T” sections placed side‑by‑side and joined at the top

single-tee

a cross‑section shaped like the letter “T” — a single vertical web (stem) supporting a horizontal flange at the top

Column casting, formwork, and reinforcement

Columns

• wood formwork

• prefab formwork

• cardboard tube

formwork

• plywood sheathing held in place

reinforcement

• placed in pour to keep strong

Formwork

Studs- vertical 2×4 from floor to top

Walers- horizontal 2×4 stretched along

Form ties- hardware used panels together

Symons pans (modular formwork)- grid-like frame ( factory-built and reusable panels)

Consolidating wet concrete

the process of removing entrapped air from freshly placed concrete to improve density, strength, and durability (vibration)

Insulated Concrete Forms (ICF’s)

Insulation and formwork in one.

Precast Concrete wall panels

Solid-non‑insulated, single‑layer concrete panels made entirely of reinforced concrete without an integrated insulation core

Composite (insulated)- concrete wall sections that combine two layers of concrete (wythes) with a continuous layer of rigid insulation in between, connected by structural ties to act as a single, thermally efficient unit

Ribbed-factory‑made concrete wall sections with a series of raised, repetitive ribs that improve strength, stiffness, and acoustic performance while allowing faster, modular construction

Tilt-up construction

a method where large concrete wall panels are cast horizontally on-site and then lifted into place with a crane, offering fast, economical, and durable building solutions used widely in North America.

Prestressing

concrete in which high‑strength steel tendons are tensioned to introduce internal compression before service loads, improving span capacity, crack control, and overall structural performance.

Pretensioning

prestresses a concrete member by stretching the reinforcing tendons before the concrete is cast

Post-tensioning

stretching the reinforced tendons after the concrete has set

Cast-in-place floors (Post-tensioned slab process)

built by pouring reinforced concrete, curing it, then tensioning high‑strength steel tendons after the concrete has hardened to introduce compressive stress and improve performance

Chairs & Bolsters

small supports used in reinforced concrete construction to hold reinforcing steel (rebar) at the correct height and spacing inside forms before the concrete is poured

Reinforcement/Rebar (and where it is placed within a slab)

In a slab, rebar is typically placed in the lower third of the slab thickness, about 1–1.5 inches from the bottom, with at least 1 inch of concrete cover to protect it from moisture and corrosion

Ferrous metals

any metal or alloy that contains iron as a major constituent, typically making up more than 50% of their weight. The term "ferrous" is derived from the Latin word "ferrum," which means iron. Common examples of ferrous metals include steel, cast iron, and wrought iron

Non-ferrous metals

metals and alloys that contain little to no iron (typically less than 1%), including aluminium, copper, zinc, lead, tin, titanium, and precious metals such as gold and silver.

Alloy

mixture of different metal to modify its properties

Metal fabricating methods

casting (into form)

polling (flattens or shapes)

extrusion (squeezing out)

forging (hitting with hammer)

stamping (forming out of sheets)

machining

Cutting

Bracking

Common metals used in Architecture

cast iron- high iron

wrought iron- hammered

steel

stainless steel-

aluminum

copper

bronze

brass

zinc

cadmium

lead

tin

chromium

magnesium

titanium

Galvanic corrosion

an electrochemical process where one metal (the anode) corrodes faster when electrically connected to a more noble metal (the cathode) in the presence of an electrolyte such as moisture or saltwater.

Steel frames

PROS-

precise and predictable

light in proportion to strength

well suited to rapid construction

CONS-

corrodes in certain environments

loss of strength under certain fire conditions

Steel shape nomenclature

a standardized coding system that identifies a shape’s type, size, and weight, enabling quick recognition in drawings, specifications, and fabrication.

• Letter code = shape family

• Numbers = dimensions (depth, width, thickness) and/or weight per foot

Structural steel joining

Rivets- a short metal pin or bolt

Welding- heating the surfaces to the point of melting

Bolts- into a socket to hold together

Steel frame seismic design

a welded moment connection for joining a beam to a column frame

Steel frame fire protection

passive systems such as intumescent coatings, vermiculite spray, and board encasement, all designed to keep steel below its critical temperature

Open web steel joists (OWSJ)

a structural element consisting of parallel top and bottom chords connected by a triangulated web system, forming a lightweight truss designed to span between bearing points and transfer loads to the supporting frame of a building (open web steel joist)

Form decking

corrugated steel sheeting used as a permanent form to support wet concrete during pouring and curing, providing an economical base for reinforced concrete slabs and eliminating the need for temporary wood forms.

Composite decking

an engineered outdoor board made from a blend of wood fibers and plastic polymers, designed to look like wood while offering greater durability and lower maintenance

Light-gauge steel construction

cold‑formed, thin steel sections (typically 12–25 gauge) shaped into studs, tracks, joists, and rafters to create lightweight, strong, and dimensionally stable building frameworks.

Cee-joist

a cold‑formed light‑gauge steel member shaped like the letter “C” that is used as a structural floor or roof joist in light‑gauge steel framing

Joist closure

small steel members—such as bars, angles, or plates—welded or riveted into the open web of a steel joist to close the triangular spaces and provide lateral stability, load distribution, and bracing between joists.

Light-gauge steel fastening methods

Self-tapping screws

Crimping

Welding

Self-tapping screws

fasteners that cut their own threads into the thin cold‑formed steel as they are driven in, allowing secure connections without a separate tapping step

Crimping

a mechanical joining method where two or more thin steel sections are deformed (pressed or clinched) together so that the material flows and locks into place, creating a strong, permanent connection without welding or bolting

Gauge (measurement of thickness)

smaller number is thicker metal

Web stiffener

a structural reinforcement plate or block added to a beam’s web to prevent buckling, crushing, or yielding under concentrated loads or shear forces.