ARCH 4511 Quiz 2

Forces

Any influence that produces a change in the shape or movement of a body.

Static loads

Loads that are gradually applied, causing the structure to respond or react slowly.

Dead loads

Static loads applied by gravity consisting of the permanent weight of the structure, fixtures, and attached equipment.

Live loads

Moving or moveable static loads from occupancy, snow, water, or moving equipment.

Dynamic loads

Loads applied suddenly with rapid fluctuations in magnitude and point of application, making them subject to inertia (such as gusts of wind or earthquakes).

Structural Forces

Any influence that produces a change in the shape or movement of a body.

Vector

A structural force defined by having both a magnitude and direction.

Moment

A force causing rotation around a point or line.

Structural equilibrium

The state of balance or rest resulting from the equal action of opposing forces, meaning the structure doesn’t break, fail, or fall down.

Point loads

A concentrated load applied to a very small area or point of a structural element.

Distributed load

A load of uniform magnitude evenly distributed over a structural element.

Structural frame

A linear framework of columns and beams defining a three-dimensional module of space capable of being expanded both horizontally and vertically.

Column

A rigid, slender structural member engineered to transmit axial compressive loads applied directly to its ends.

Beam

Rigid structural members that carry transverse loads to supporting elements, experiencing bending and deflection under load. Trusses are pre-engineered triangulated framing frameworks consisting of wood chords and webs to span longer floor or roof distances.

Beam efficiency

Structural performance that is directly affected by changing the cross-section dimensions of the beam (width vs. depth).

Bearing / Loadbearing wall

Continuous vertical elements that handle loads like a very wide column; they are most effective when supporting a uniformly distributed load.

One-way span

A structural configuration where stresses and loads are carried in one direction to the preceding structure; best for longer, rectangular layouts with repeating bays.

Two-way span

A structural configuration where stresses and loads are carried in two directions to the supporting structure; best for square (or combined square) layouts.

Lateral stability

A system metric ensuring a building can withstand all horizontal load conditions (like wind or seismic action) alongside vertical gravity loads.

Horizontal diaphragm

A horizontal structural plane (such as a floor slab or roof decking) acting as a rigid beam to transmit lateral wind or earthquake forces down into vertical shear walls or braced frames.

Rigid Frame

A framing assembly where joints (corners) are explicitly braced to resist both forces and moments, making it rigid within its own plane.

Braced Frame

A structural frame stabilized against horizontal displacement via structural diagonal members.

Knee bracing

Short, diagonal structural members cutting across the corner of a frame joint to stiffen the connection between a beam and a column against lateral loads.

K-braces

A variation of diagonal framing where pairs of braces branch outward from columns to meet at a central point on a beam, tracking an angle that mimics the letter "K".

Cross bracing

Intersecting structural diagonal members placed in an "X" configuration inside a structural frame bay to distribute tension and compression forces.

Shear wall

A rigid vertical partition used to handle lateral forces, typically oriented along the critical short dimension of a building structure

Environmental attributes of Wood

Wood is the only major structural material that is renewable and possesses a significantly lower embodied energy content than competing materials.

Sustainable forestry practices

Forest management workflows utilizing selective harvesting or systematic clearcutting and replanting to eliminate downstream degradation like soil erosion or habitat loss.

Sustainable forestry certifications

SFI represents an industry certification method. FSC represents a validation method ensuring complete chain-of-custody tracking from the harvest site to end-use.

Chain-of-custody

A systematic tracking process from harvest to end-use confirming that wood products originated from certified sustainable timberlands.

Softwoods

Wood harvested from evergreen trees containing tracheids (vertical cells) and summerwood/springwood rings; primarily used for structural framing, sheathing, and paneling.

Hardwoods

Premium fine-grain woods harvested from deciduous trees; commonly used for interior moldings, paneling, furniture, and finish flooring.

Timber

Large-dimension milled ____ components used in heavy loading grids.

Lumber

Standardized wood items systematically milled, kiln-dried, and dressed from raw tree logs.

Plainsawing

A basic log milling process that produces boards with a broad grain figure on their faces.

Quartersawing

A premium milling process that produces a vertical grain structure, visible on the face of the board as tightly spaced parallel lines.

Seasoning distortions

Wood defects stemming from moisture loss during drying, categorized into four shapes

Nominal vs. Actual dimensions in wood

Nominal represents the rough size before milling (e.g., a 2x4), while actual dimensions denote the true dressed size after planing (e.g., a 2x4 is actually 1½" x 3½").

Composite wood products

Engineered building materials manufactured by gluing together smaller pieces, strands, or veneers of wood.

Glued Laminated Timber

A structural timber component manufactured by bonding together multiple smaller wood laminations with parallel grains using structural adhesives.

Laminated Veneer Lumber

Efficient wood components manufactured by pressing and gluing 3 mm thick rotary-cut softwood veneers under phenolic resin, aligning all plies parallel.

Structural Veneer Lumber

Linear components with a maximum width of 500 mm that are made from several individual LVL elements glued together.

Parallel Strand Lumber

High-load linear members built from 25 mm wide wood strips (Douglas Fir or Southern Yellow Pine) aligned with the beam axis and glued with phenolic resin.

Plywood

A wood panel composite built from cross-banded softwood plies glued together with perpendicular grain directions.

Particle boards

Internal fitting panels consisting of relatively small wood chips or fibers lying parallel with the plane of the board and bonded with synthetic resins.

Oriented Strand Board

A structural panel built by bonding compressed wood strands or wafers oriented in perpendicular layers with exterior-grade binders.

Wood veneer

Exceptionally thin slices of wood (typically rotary sliced for structural plywood, or plain/quarter sliced for hardwoods) glued over substrates.

Veneer grades

Quality stamp scales matching face appearance

APA label

A quality-certified gradestamp found on the back of panels indicating panel grade, span rating, thickness, and exposure durability classification.

Treated lumber

Wood products chemically pressure-treated within a closed cylinder to safeguard the fibers against decay, rot, and insect infestations.

Composite deck lumber

Exterior boards made from a blended configuration of recycled plastics and wood fibers to provide a weather-resistant finish surface.

WLFC fire protection

The use of protective drywall (gypsum wallboard) layers and fire walls to protect wood framing cavities from flame exposure.

Balloon frame

An old framing variation where vertical wall studs run continuously across multiple floors from the base up to the roof rafters.

Platform frame

The modern framing process where floor platforms are built first, and then wall frames are assembled horizontally on top of them and tilted up into place.

Header

Horizontal framing pieces placed over structural openings (doors/windows) that are doubled up wherever upper gravity loads require load redirection.

Trimmer

Vertical framing studs that support horizontal headers directly at their ends to carry loads down to the base plates.

Cripple

Short vertical framing studs positioned above headers or below rough windows sills.

King stud

Full-height vertical studs positioned immediately adjacent to trimmer studs at the borders of door or window rough openings.

Top plate

Double horizontal boards that cap the vertical wall frame, designed to overlap at corners to tie walls together and support upper joists.

Sole plate

The continuous bottom horizontal member of a wall frame anchored directly to the subfloor platform.

Joist

Parallel horizontal members designed to support floor loads, typically spaced at standard 16-inch or 24-inch intervals.

Rim joist

A continuous perimeter framing member that floor joists butt directly into around the building outline.

Bridging

Structural members installed at mid-span between floor joists to resist distortion and twisting.

Wood floor joist options

Categories of horizontal structural members, which include solid dimensional lumber, SCL joists, wood trusses, and wood/metal trusses.

Solid dimensional lumber

Traditional structural framing lumber sawn directly from raw tree logs.

I-Joist

Engineered framing components manufactured with sawn or laminated veneer lumber flanges along the edges of a single plywood or OSB web.

Truss joist

Open-web floor structures utilizing 2x4 wood chords and webs with metal toothed plate connectors.

Composite truss

Structural joists combining wood framing chords with diagonal steel web components or tubing webs.

Stringer

Inclined structural stairs framing cut from 2x12 boards using a framing square to support stair treads and risers.

Advanced/Stack/OVE framing

An engineered framing optimization system that spaces studs precisely at 24 inches on center (o.c.) to eliminate redundant wood members and maximize cavity insulation space.

Nail types

Standard metal wire fasteners classified by penny sizes (e.g., 16d commons or 10d sinkers) and shapes (box, finish, cut, or roofing nails).

Nailing types

Methods of driving mechanical fasteners, consisting of face nailing, end nailing, or toe-nailing at an angle.

Screw types

Threaded fasteners classified by head style (oval, flat, pan), drive configuration (Torx, slotted, Phillips), and thread density.

Sheet metal connectors

Galvanized metal framing devices (such as joist hangers) used to mechanically reinforce joints wherever joists meet at right angles.

Why can we use wood in this type of construction?

Because heavy timbers contain massive profiles that are recognized by code as fire-resistant due to their predictable charring behavior under exposure.

Minimum thicknesses and dimensions

Specific building code requirements for Type IV construction, dictating 8"x8" columns, 6"x6" beams/girders, 3" thick floor decking, and 2" thick roof decking.

Pintel

A heavy cast iron vertical column connector cap that passes through floor plates to transfer loads column-to-column while accommodating wood shrinkage.

Split ring connectors

High-capacity connectors consisting of a metal ring inserted into circular grooves between joining timber faces and tightened with a central bolt.

Shear plates

Malleable iron round plates inserted flush with the face of a timber, used in pairs for demountable connections or singly for wood-to-metal joints.

Firecuts

An angled sloping cut on the ends of timber beams resting inside masonry walls, preventing a burning, collapsing beam from prying or destroying the wall masonry socket.

SCL for frame with metal connectors

Large-dimension structural composite lumber columns and beams connected using heavy-duty metal connector plates.

Cross-Laminated Timber

Large timber panels manufactured with layers of glued lumber where each layer is turned 90º for two-way strength.

Nail-Laminated Timber

Structural wood panels constructed from dimensionally identical lumber pieces stacked on edge and mechanically fastened with nails or screws to provide one-way strength.

Four environmental factors a wall must control

1. Heat - Managing thermal mass and conductivity.

2. Infiltrating air (drafts) - Sealing the envelope against air infiltration.

3. Moisture (water in liquid phase) - Stopping driving rain or bulk water migration.

4. Water vapor - Blocking humidity shifts inside assemblies.

Additional factors a wall must control

Sound, Light, Desired fresh air, Passage of people and goods, FIRE

Ashlar

Building stone that has been squared and finished into organized coursed or random layout patterns.

Brick raw material and manufacturing method

Built using clay and shale as raw inputs, molded to shape, and subsequently fired in kilns.

Bricks

Highly durable, reusable blocks made of fired clay or shale that offer excellent thermal mass capabilities.

Cored, hollow, frogged

Core options in brick units that reduce raw material use, permit even kiln heating, allow steel reinforcement insertion, and offer extra bearing space.

Course

A single horizontal layer of bricks or other masonry units.

Wythe

A single vertical layer of masonry units that is exactly one unit thick.

Header

A brick laid so as to bond two vertical wythes together.

Stretcher

A brick laid flat with its face parallel to the wall line and its long dimension horizontal.

Soldier

A brick laid on its end vertically with its long face parallel to the exterior wall face.

Rowlock

A brick laid on its narrow face with its end visible along the exterior wall plane.

Bed joint

The continuous horizontal mortar layer placed beneath each masonry unit.

Head joint

The vertical mortar joint installed between adjacent units within a single course.

Bond

The interlocking pattern of masonry units (such as Common, English, Flemish, or Running bonds) configured to bind a monolithic structure together.

Standard brick dimensions

A modular geometry scale where three horizontal brick courses plus mortar joints equal 8 inches vertically, and one brick length plus one mortar joint equals 8 inches horizontally.

Concrete Masonry Units

Blocks formed from concrete using sand, gravel, cinder, or pumice; all share a minimum compressive strength requirement, though heavier aggregate units are more durable.