Chap 2 Constructive Terms Of Building Design

Question 0

Passive fire protection is

Answer 0

1. The fire containment provided by a structure( partition walls with spray on fire retarding and fire resistive construction)
2. Often fails and cannot be depended on stop fire spread

Question 1

Active fire protection is

Answer 1

Fire protection provided by automatic sprinklers and firefighters hose

Question 2

Cold formed steel beam is

Answer 2

A sheet steel c-beam used in lightweight steel floor construction

Question 3

Convenience stair

Answer 3

Opening in a floor slab for a stair between floors

Sometimes called access stair

Question 4

Corner safe areas

Answer 4

Four flanking areas around a burning building

Question 5

Demising wall

Answer 5

A partition wall that extends from floor slab to floor slab above

Question 6

Fire resistive rating is

Answer 6

A relative rating to indicate in hours how long a wall , floor ceiling beam or column will sustain performance during a fire

Question 7

Fluted metal steel deck

Answer 7

Sometimes called a corrugated metal deck

Wavy piece of sheet steel deck used to support concrete floor.

Question 8

Frame tube construction

Answer 8

1 building structure with hollow tubular exterior (perimeter columns )bearing walls
2. WTC towers WERE FRAME TUBE CONSTRUCTION whose exterior hollow bearing walls varied from 4” thickness near bottom or only 1/4 “ thickness near top

Question 9

Gravity load

Answer 9

Combination of live and dead load

Question 10

Purlin

Answer 10

A timber laid horizontally and perpendicular to support the common rafters of the roof

Question 11

I beam

Answer 11

Wood or steel
Consists of center called a web section and top and bottom flanges
Wood I beams has a web section of glue and wood shavings connecting the top and bottom flanges which are made of 2x2 wood sections

Question 12

Laminated beams

Answer 12

It’s glued or layered composition beam

Laminated wood chips are used in lightweight I-beams. And layers bent wood is used in timber chord truss construction

Question 13

Bridge truss

Answer 13

A perpendicular truss used in steel bar truss floor systems to provide lateral stability

Question 14

Hat truss

Answer 14

A means of load distribution connecting core columns and perimeter columns
Used on top floor of WTC towers

Question 15

Multilevel floor collapse

Answer 15

A floor failure that causes one or more floors below and one or more enclosing walls to collapse

Question 16

Global collapse

Answer 16

A total collapse of building

Question 17

Progressive collapse

Answer 17

The initial structural failure spreads from structural element to structural element resulting in a collapse of the entire structure or a disproportionately large part of it

Question 18

Interstitial space

Answer 18

Also known as a plenum space
Concealed space btwn floors used to contain large mechanical and electrical equipment
Can be up to 8 feet high
Can contain a walkway for access for maintenance, repairs and renovations

Question 19

Sprayed Fire-Resistive material (S.F.R.M)

Answer 19

1. Insulation or fluffy sprayed on fire-retarding used to protect steel from the heat of the fire
2. Must cover the steel entirely
   3: must be proper thickness or density
3. Must adhere to the steel and not flake off when exposed to air movement in the HVAC plenum. Area

Question 20

Timber

Answer 20

Wood larger than 2x4 thickness

Question 21

Arch

Answer 21

1 curved masonry piece used as a support over an open space

2. The removal or destruction of any part of an arch will cause the entire arch to collapse

Question 22

Beam

Answer 22

A horizontal structural member subject to compression tension and sheer

Question 23

3 ways a beam can be supported are

Answer 23

Cantilever
Simple support
Continuous support

Question 24

Cantilever support of a beam

Answer 24

Beams supported at one end only | Least stable

Question 25

Simple support beam is

Answer 25

Beam supported at both ends | More stable than cantilever

Question 26

Continuous beams are

Answer 26

Supported at both ends and at the center | Most stable

Question 27

Joists are

Answer 27

A piece of lumber used as a floor or roof beam | Terms joist beam rafter are used interchangeably

Question 28

Restrained beam end

Answer 28

Welded, nailed bolted or cemented end of the floor or roof beam Restrained beam end will not collapse as readily as an unrestrained beam end at fires Example: a wood beam cemented into cavity of brick wall

Question 29

Unrestrained beam end

Answer 29

A beam resting on a support held in place only by gravity Collapse at fires more readily than a restrained or fixed beam end Examples : fire cut beam ,beam resting on corbel ledge ,beam resting on girder

Question 30

Fire cut beam

Answer 30

1 gravity supported beam end designed to release itself from masonry wall during a collapse 2. The end of the beam where it rests within the cavity of the masonry wall is cut on a angle 3. An unintended indirect advantage of fire cut beam is the safety of FF operating outside the building near the enclosed walls . A floor collapse will not topple the walls outward in top of them 4. The disadvantage to ff operating inside of fire cut beam is early floor collapse

Question 31

Ballon frame construction

Answer 31

1. Exterior walls have studs that extend continuously from the foundation sill to the top plate near then attic 2. Fire , smoke and heat can spread from the cellar area or intermediate floors to the attic space in the concealed space between the exterior walls 3. If a non- bearing wall fails the continuous studs will cause the wall to fall straight out in one section at a 90 degree angle 4. If bearing wall falls it can cause collapse of floors it supports

Question 32

Braced frame construction

Answer 32

Also called Post and girt 1. Vertical timbers called posts reinforce each of the 4 corners of the structure 2. Horizontal timbers called girts reinforce each floor level 3. The posts and girts are connected by mortise and tenon joints 4. This type usually fails inward outward type collapse where: A. Top part of the wall collapses inward on top of the pancaked floors B. The bottom part of the wall collapse outward on street

Question 33

Mortise is

Answer 33

Structural member used in braced frame wooden construction It's a hole cut in timber that receives the tenon Mortise opening reduces the thickness of the timber and reduces the load carrying capability of the timber at this point When braced frame construction fails it often fails at the mortise and tenon connection

Question 34

Tenon

Answer 34

1. A projecting reduced portion of the timber designed to be inserted into the mortise hole of another timber 2. because of it's reduced size the tenon connection is the weakest portion of the reduced timber

Question 35

Platform construction

Answer 35

Has one completed level of 2x4 inch wood enclosing walls raised and nailed together The floor beams and floor deck for the next level are constructed on top of these walls The next level of 2x4 wood enclosing walls are constructed on top of the first completed level From a fire protection point of view , platform construction is superior to ballon and braced frame construction because there are no concealed wall voids extending for more than one floor level

Question 36

Curtain fall collapse of an exterior masonry wall

Answer 36

1. Exterior masonry wall drops like a falling curtain and drops straight downward 2. This often occurs to brick veneer , brick cavity or masonry backed stone wall 3. Can occur from the use of master stream striking a masonry veneer wall at close range

Question 37

Inward / outward collapse of an exterior wall

Answer 37

1. The exterior walls breaks apart horizontally 2. The top part of the wall collapses inward back on top of the structure 3. The bottom part of the wall collapses outward onto the street 4. Wooden braced frame buildings collapse in this manner 5. timber truss roof collapses can cause a 2nd collapse of the front or rear wall in This manner

Question 38

90 degree angle collapse of the exterior wall.

Answer 38

The wall falls straight out as a monolithic piece at a 90 degree The top of the falling wall stricken the ground a distance from the base of the wall that is equal to the height of the falling section 3. Chunks of brick or steel lintels may bounce or roll out beyond this distance

Question 39

Lean -to floor collapse

Answer 39

A floor collapse in which one end of the floor beam remains partially supported by the bearing wall The other end of the floor beam collapses onto the floor below and is either supported ("supported lean to collapse") or unsupported ("unsupported lean to collapse )

Question 40

Pancake floor collapse

Answer 40

The collapse of the floor sectio down upon the floor below in a flat pancake style Pancake collapse occurs when the floor beams pull loose or collapse at both ends

Question 41

Tent floor collapse

Answer 41

A floor collapse in the shape of a tent where an interior partition wall or interior wall holds up the center of the fallen floor

Question 42

v-shape collapse

Answer 42

The collapse of a floor at the center of the floor beams | Both ends of the floor section remain partially supported or rest up agonist the outer bearing walls

Question 43

Lean over building collapse

Answer 43

A type of wood frame building collapse where the building collapse to one side It will be Indicated by the structure starting to tilt to one side

Question 44

Secondary collapse

Answer 44

The collapse of portions of a burning taller structure onto a smaller structure causing the collapse of the smaller building

Question 45

According to Dunn a load transmitted ____ through a structural member is least likely to collapse

Answer 45

Axiallly

Question 46

According to Dunn which loads can cause collapse during fire

Answer 46

FLID FIRE LIVE IMPACT DEAD

Question 47

Dunns Hierarchy of building elements form greatest to least

Answer 47

1. Bearing wall 2. Column ) 3. Girder 4. Beams floor and roof 5. Decks

Question 48

3 common Types of stress on structural members are

Answer 48

Compression Tension Shear

Question 49

All of the following according to DUNN are considered primary structural members

Answer 49

``` Bearing walls Columns Girders Ridge pols Hip rafters Headers Trimmer floor beams ```

Question 50

The most unstable wall a ff will encounter is

Answer 50

A ornamental facade parapet wall is often a free standing decorative wall which frequently collapses during fire

Question 51

According to DUNN Structural collapse during a fire is directly portioned too

Answer 51

Fire load The greater the fire load the greater the possibility of structural collapse