Brannigan Flashcards
Masonry wall breach incorrect
A: If parts of the wall crumble easily while operating, the breaching operation should be haulted
B: Triangular hole should be made
C: Loads coming down a wall to an opening such as a door/window, (a vertical path) should not be followed because the load splits on both sides of the opening
D: While breaching, a wall column is found indicating that the members can continue ops in that area
D Brannigan ch 2
stop breaching operations immediately
Choose the incorrect sign for braced walls.
A: Braced walls are a basic sign that a wall is in distress
B: Braces of protected structural steel, or worse, of steel cable, will fail at fire temperatures
C: Bracing is signaled by stars, plates channel sections, or other spreaders or straps tying the front wall to the side wall
D: The walls may be tied together across the building, or tied to floor beams
E: Braces are not always an indication of instability
B Unprotected structural steel Ch 4
Choice E is followed by “Some buildings have walls that are tied to the floors to make the structure more rigid” and “Generally, these can be identified by spreaders, usually stars, in a REGULAR PATTERN”
Correct
A: The top chord of a truss is under tension and acts like a column
B: If a 12 foot column is braced at its midpoint (at 6 feet), and the bracing suddenly fails at a fire, the column’s load carrying capacity decreases to 1/4 of what it was able to support with the bracing
C: Steel columns are generally box shaped, cylindrical, or shaped like the letter “I”
D: Columns have considerable reserve strength beyond their initial yielding
B
A- The top chord of a truss is under compression and acts like a column.
C- Steel columns are “H”-shaped, box-shaped, or cylindrical. Steel beams are shaped liked the letter “I” because the depth determines strength
D- Once a column starts to yield, there is generally very little reserve strength left and the column is on the verge of total collapse
Know this chapter for sure
Brannigan Chapter 2
“Arches” according to Frank Brannigan. Which statement is incorrect?
A: The arch combines the function of the beam and the column
B: The arch is under compression its entire length
C: If properly built, arch connections are not important to its strength
D: The thrust of an arch is outward
E: The removal of any part of an arch will cause a localized collapse of the arch
E The removal of any part of an arch can cause the collapse of the entire arch
Brannigan ch 2
Choose incorrect
A. Water tank on roof is considered a Live load
B. Concrete vault is considered a dead load
C. Movable safe is considered a live load
D. Steel beam resting on a masonry wall is considered a concentrated load
A Water tank is a dead load; the water inside of the tank is a live load
Cables used to brace failing bldgs can be made from Cold Drawn Steel which fails at _ degrees Fahrenheit A. 400 B. 650 C. 800 D. 1100
C
As the length of a beam increases, the beam's loading carrying capacity decreases. A 12' beam can carry _ the load of a similar 6' beam A. 1/4 B. 1/2 C. 1/3 D. 1/8
B
Choose the incorrect about columns
A. Failure of a column is likely more sudden than failure of a beam
B. Failure of a column may precipitate collapse of entire portion of bldg dependent on that column
C. Slightest indication of column failure should cause bldg to be cleared immediately
D. Most efficient shape for a column is one that distributes material equally around the axis as close as possible to center of cylinder
D Away from center
Which is an incorrect choice when describing compression and tension
A: When reinforced concrete is used, the concrete provides the tensile strength and the steel provides the compression strength
B: Steel is almost equally strong in compression and tension
C: Wood varies greatly in its compression strength, depending on the direction in which the load is applied
D: The shape of steel is not a consideration in tensile loads
A- When reinforced concrete is used, the concrete provides the COMPRESSION strength and the steel provides the TENSILE strength
Look at D….The shape of a material affects its ability to resist a compressive load or a deflective one
Chapter 2
The carrying capacity of a beam is incorrect in which choice?
A: If another 2x4 is laid alongside a similar 2x4 the carrying capacity is increased by a factor of two
B: The load carrying capacity of a beam increases by the square of its depth. A 2x8 can carry four times (square of 2) the carrying capacity of a 2x4
C: As the length of the span (distance between supports) of a beam increase, the safe load capacity increases in direct proportion
D: The transfer beams are designed to receive the concentrated load of a column and deliver it laterally to supports
C Decreases
The load carrying capacity or strength of a beam:
Increases/decreases in direct proportion to changes in its width
Increases/decreases in proportion to the square of changes in its depth
Increases/decreases in direct proportion to changes in its span or length
Chapter 2
The correct definition regarding wall bracing can be found in which choice?
A: Buttresses are masonry structures built on the inside surface of the wall
B: Pilasters are masonry columns built on the outside surface of the wall
C: Wall columns are columns of steel, reinforced concrete, or solid masonry in a block wall
D: Cavity or hollow walls are built 3 wythes separated by a space for rain drainage or insulation
C A- Outside B- Inside D- 2 wythes Chapter 2
Every Battalion Chief should know how an Arch works, especially during a fire. Choose the incorrect statement made about Arches
A: The arch combines the function of the beam and the column
B: The arch is under tension its entire length
C: The removal of any part of an arch can cause the collapse of the entire arch
D: Arches tend to push outward at the base and therefore must be either braced or tied
B Under COMPRESSION
Also, cutting through tile arch floors, such as for distributor or cellar pipe is dangerous because the removal of one tile can cause the entire arch to fail
Chapter 2
Which choice does not illustrate steel during a fire
A: Heated to 1000 degrees, a steel member will expand 9 ½ inches over 100 feet in length
B: If steel beams are restrained by a masonry wall, and the temperature of the fire remains around 1000 degrees, the expanding steel may cause displacement of the masonry
C: In hot fast fires, failure temperatures are reached rapidly and the lateral thrust against the wall is maximized
D: If steel is raised to temperatures above 1000 degrees, it starts to lose strength rapidly
C In hot fast fires, failure temperatures are reached rapidly and the lateral thrust against the wall is MINIMIZED
Chapter 7
Upon arrival of a construction worker that fell into a hole, you discover that the earth under the structure that is adjacent to the excavation hole your members are working in may tend to shear sideways into the hole. Incorrect
A: Rows of horizontal beams called Solider Beams are driven into the ground
B: The rows of Solider beams are tied together with a beam called a Waler
C: Diagonal columns called Rakers brace the entire structure
D: The Rakers may be loaded to twice the load that would be permitted if they were permanent structures
A Vertical beams
Chapter 7
Metal Roof Deck incorrect
A: There will be a characteristic orange/yellow wave of fire several inches deep advancing rapidly on the underside of the roof
B: These fires can be controlled by the continuous application of water to the underside of the roof. By cooling the steel, the tar is prevented from generating gas. Extinguishing the fire by removing the fuel
C: Do not hesitate to throw water into the smoke, even though the target may be invisible
D: A ladder pipe or TL stream directed downward onto the roof is useless
E: The ladder pipe or TL stream can be useful if it can be maneuvered to where it can deliver the heavy stream onto the underside of the roof
A There will be a characteristic BLUE wave of fire several FEET deep advancing rapidly on the underside of the roof
Chapter 7
Choose the incorrect statement in regards to Post-tensioning concrete
A: Strand wires or bars are encased in plastic or paper tubing, or wrapped, to prevent and adhesion with the concrete
B: Until the tendons are stretched, the entire weight of the concrete is on the falsework. The weight of the concrete is transferred to the columns only when tension is completed
C: When the concrete reaches a specified strength, the steel tendons are stretched and anchored at the ends of the unit. ( This is known as stressing the tendons or jacking the cables)
D: Major advantage of post tensioning is that floors can be thicker
D Thinner
Chapter 8
Falsework (formwork) is a temporary structure erected to support concrete work during construction. It is also the mold that shapes concrete. When formwork is used to construct a wall, all Chiefs should know that if a collapse occurs which is incorrect?
A: It usually goes out at the top
B: Workers may be trapped, particularly between falsework and sides of the excavation
C: There will probably be no reinforcing steel to interfere with the rescue
D: Rescue will involve uncovering faces, supplying oxygen, and digging victims out
E: If it is necessary to retard the setting of the concrete, as much sugar as can be obtained should be worked into it
A It usually goes out at the bottom
Look at E…Concrete containing sugar will set slowly, if at all
Chapter 8
Smoke and Fire Containment can be only illustrated in which choice?
A: The chief mover of smoke in a fire is caused by the thermal energy of the fire
B: The principal smoke moving mechanism in a high-rise building is gravity
C: During positive pressure ventilation, the exhaust opening can provide a horizontal or a vertical ventilation of the contamination
D: During positive pressure ventilation, it is most advantageous to pressurize the structure on the leeward side and exhaust contaminants on the windward side of the building
E: If the prevailing wind cannot be used to advantage, positive pressure ventilation has proven effective against winds up to 35 mph
C
A Gravity
B Thermal energy of fire
D During positive pressure ventilation, it is most advantageous to pressurize the structure on the WINDWARD side and exhaust contaminants on the LEEWARD side of the building
E 25 mph
Also, opening a single window on the leeward side of the building in the fire area will permit the excess pressure to vent, taking much of the smoke with it
Opening several windows can dilute this effect
Chapters 10 and 11
Two terms that describe atmospheric conditions are Lapse and Pause. Choose the most correct description
A: When the atmospheric temperature is constantly decreasing as height increases, the condition is called Lapse. Under Lapse, smoke will move up and away from the building
B: If there is a layer of air warmer than the air below, the condition is called Lapse, and the layer is called the inversion layer
C: Lapse acts as a roof to rising smoke
D: High-Rise building will never be tall enough to penetrate the inversion layer
A B- the condition is called Pause C- Pause acts as a roof to rising smoke D- A High-Rise building will be tall enough to penetrate the inversion layer Chapter 11
Chief officers must know how wind can effect a building fire, specifically when it comes to High-Rise bldgs. Choose the incorrect
A: Closely spaced high-rise buildings can create a River effect, where the wind increases velocity as it squeezes through a narrow opening
B: Wind blowing against a building seems to split about 2/3 of the way up the building. The upper portion flows up and over the roof
C: The lower portion flows downward forming a vortex next to the building
D: Wind increases in velocity as it flows downward
A Canyon Effect
Chapter 11
Stack Effect during the winter months incorrect
A: The greatest flow of air will be at the top floor, with the flow gradually decreasing as the height above ground increases
B: At a point about 1/3 to ½ the height of the building the flow is reduced to zero. This is called the neutral zone
C: Above the neutral zone, the flow reverses and travels from the shafts to the floors
D: The pressure increases floor by floor and is greatest at the top
A The greatest flow will be at the FIRST floor
Also. It is common practice to hook open a lobby door to make it easier to bring equipment in. This may lower the neutral zone several floors and increase the number of floors polluted by a fire below the neutral zone
Chapter 11
During a fire a pressurized stair in a High-Rise building should be reserved for \_\_\_\_\_\_\_ A: Attack B: Evacuation C: Positive Pressure Ventilation D: Negative Pressure Ventilation
B Chapter 11
For any unit area, steel has how many more times the compressive strength than concrete? A: 10 B: 15 C: 20 D: 25
B
Which is an incorrect description of a steel column/beam
A: While steel beams are I-shaped, steel columns are H-shaped, box shaped, or cylindrical
B: Steel beams are shaped liked the letter ”I” because the width determines strength
C: Steel columns are shaped like the letter “H” and of a dimension that permits a circle to be inscribed through the 4 points of the “H”
D: It is more difficult to attach beams to round columns than to rectangular ones, so less efficient rectangular columns are often used
B Depth determines strength
