Structural Systems
37) The joint where inclined and vertical steel girders meet in a rigid frame industrial building is called a: A) "Crown". B) "T". C) "Leg". D) "Knee".
D Notes) Page 80;
1) Which of the following statements is FALSE? A) Masonry walls are found usually in Type III construction. B) Unprotected steel will be found in Type II building. C) In order to be classified as a Type I structure, the steel framing must be fire-protected. D) Firefighters should be cautious that one building can contain two different construction types, such as a Type II main structure with a Type III wing.
A Notes) Page 71;
Concrete has poor tensile strength, therefore examples in A, C, and D all require reinforcement. An arch is an structural system that functions on compressive forces, and as well all know, concrete is very resistant to compressive forces. 3) Why are steel reinforcing bars ("rebars") designed with deformations or "ridges" perpendicular to the length of the bar? A) So that poured concrete can adhere to the reinforcement bars. B) The perpendicular ridges counteract the tensile forces exerted by the wet concrete. C) Rebars are "hot-rolled" and therefore do not exhibit the smooth surface that a more expensive cold-rolling process produces. D) The ridges counteract tensile forces exerted on the steel and the concrete by the dead and live loads.
A Notes) Page 71;
A, C, and D are entirely fictitious constructions that increase rather than reduce tensile forces on the concrete beam. 11) Under what circumstances is tension applied to steel reinforcing strands of a beam AFTER the concrete has hardened? A) When applying posttension reinforcing to the beam. B) When the beam must be cast in place. C) When rehabilitating older or damaged concrete beams in an existing building. D) When a flat slab concrete frame is being constructed.
A Notes) Page 73;
17) Which of the following cast-in-place structures is also known as a "two-way slab" for its reinforcement pattern? A) Waffle construction. B) Slab and beam frame. C) Flat slab concrete frame. D) Web concrete frame.
A Notes) Page 75;
Overlap of the rebars at the joint is essential to transfer the loads between successive pours. Structural Systems Knightlite Software 5 16) Where do sheer forces normally develop in flat-slab panel? A) At the intersection of the column edge and the slab. B) At the center of the slab between column supports. C) Where the slab overlaps the centerpoint of the column. D) Concrete slabs are subject to tension failure, not sheer failure.
A Notes) Page 75;
23) What is the name of the non-load bearing wall on the exterior of a concrete frame building? A) "Curtain wall". B) "Skin". C) "Facade". D) "Fire Wall".
A Notes) Page 76;
Structural Systems Knightlite Software 7 24) What is the usual fire resistance ratings of concrete structural systems? A) 1-4 hours. B) 2-6 hours C) 6-8 hours. D) Indefinite.
A Notes) Page 76;
The connections between precast members are subject to the deteriorating effects of the fire. 26) The fire resistive characteristics of a concrete structural system is NOT affect by which of the following factors? A) The angle of the concrete. B) The density of the concrete. C) The load supported by the concrete. D) The concrete thickness.
A Notes) Page 76;
Look at Figure 7.27 on page 78. Structural Systems Knightlite Software 9 32) Which of the following reinforcement methods best counteracts lateral forces in a steel rigid frame building? A) Cross bracing and sheer panels. B) Angle brackets and reinforcing rods. C) Concrete corbels. D) Masonry buttresses.
A Notes) Page 78;
Actually masonry buttresses could be used to fight lateral forces, but their application is clumsy and expensive and best left to medieval cathedrals. 33) Which of the following structural frame systems would a firefighter would likely find supporting the roof deck of a home improvement store? A) Steel truss. B) Girder and beam. C) Rigid frame. D) Concrete tee.
A Notes) Page 79;
38) Which of the following examples would be an appropriate application of a steel cable suspension system? A) Support of a cantilevered canopy over a ferry terminal. B) Support of a roof system in a post and beam barn. C) Suspension of a space frame. D) Supporting a 4-story lobby ceiling in a skyscraper office building.
A Notes) Page 80;
45) How do gusset plates protect the fasteners in a joist girder from fire deterioration? A) Increases the steel mass at the connections, thereby requiring more heat to cause failure in the fasteners. B) When mounted between the girder and the bolts, the fasteners are shielded from the radiant heat source, thereby increasing the time before failure. C) Provides a rigid connection that stiffens up the frame and resists buckling and failure. D) Gusset plates do not provide any extra radiant heat protection for steel frame fasteners.
A Notes) Page 82-83;
Structural column supports in any building should not have a slenderness ratio over 120. Structural Systems Knightlite Software 12 44) In a beam and girder or truss frame, what structure is applied to protect and strengthen the points of connections? A) A gusset plate. B) A split ring connector. C) A stay roll. D) Gypsum wallboard.
A Notes) Page 82;
A: The question was what structural miscalculation did the designers make. B: The question does not support the conclusion that codes of the day were violated. In all likelihood, codes did not require sprinklers for such a use in 1967. D: There is no reference to gussets in the question. Besides gussets are used primarily in heavy duty beam and girder assemblies, not in open-web steel roof trusses. Structural Systems Knightlite Software 13 47) What structural system is often referred to as "ordinary construction"? A) Masonry exterior walls with internal wood framework. B) Poured-in place concrete walls with pre-cast concrete curtain walls. C) Girder and beam framework with glass curtain walls. D) Light-frame wood construction..
A Notes) Page 83;
48) Which of the following statements is TRUE? A) Buildings with masonry bearing walls are found in fire-resistive and non-fire resistive buildings. B) Interior masonry bearing walls are designed primarily to provide lateral support to the building. C) Cast iron columns used in conjunction with masonry bearing walls is a hallmark of construction dated between 1920 and 1950. D) Stone veneers applied to exterior concrete block masonry walls is called "extraordinary construction".
A Notes) Page 84;
Steel was usually not present in 19th century mill structures. A36 framing evident in such structures is usually an indication of later retrofits. Nominal wood framing (2" x 12", 6" x 6", etc.) was not standardized until the 20th century. 59) Under which of the following circumstances would a "beam pocket" be employed? A) To make the connection between a concrete block foundation and the wood floor joists of a residential building. B) To facilitate the attachment of a gusset plate to protect connections in a beam joist. C) To fasten wooden floor joists to a carrying beam in a small commercial building. D) To reinforce a parapet overlooking the sidewalk side of a commercial building.
A Notes) Page 87;
A fire cut is actually designed to save the wall not the joist. The intent is to avoid the burned timber acting as a lever to destabilize the masonry bearing wall. 61) Which of the following masonry units exhibits the least amount of fire resistance? A) Hollow concrete blocks. B) Fire-rated CMUs. C) 18-inch brick wall. D) 8-inch solid concrete masonry unit.
A Notes) Page 88;
Except for a log cabin, wood is never used as a solid wall material. 67) Which of the following wood structures would generally NOT require structural engineering prior to issuance of a building permit? A) Residential garage. B) Heavy timber retail outlet. C) Post and Beam doctor's office. D) Prefabricated truss roof system for a indoor equestrian ring.
A Notes) Page 90;
69) Which of the following wood construction types characteristically uses 6" x 10" (152 mm x 254 mm) beams? A) Heavy timber framing. B) Balloon construction. C) Post and beam framing. D) Light wood framing.
A Notes) Page 91;
The header course indicator may not always be accurate. Some bearing walls use horizontal ties, while some veneers use half bricks to simulate header courses. Use all of the evidence, including age of the structure and use to make your determination. Structural Systems Knightlite Software 23 81) To a firefighter, what is the principal advantage of platform framing over balloon framing? A) Platform framing provides fire stops between floors, thereby inhibiting fire communication between floors. B) Platform framing is cheaper and easier to construct than balloon framing. C) Platform framing can be pre-fabricated under controlled conditions that will improve quality of the finished product. D) Balloon framing is a safer and easier framing system for the fire service to attack and knock down.
A Notes) Page 93;
A: Sulfuric acid is corrosive and will leave nothing of the insulation. B: Aluminum and especially magnesium shavings will accelerate the rate of combustibility. D: Impractical and unacceptable to most homeowners. 79) Which one of the following statements is FALSE? A) A brick veneer provides additional structural bearing capacity to an exterior wall. B) Brick veneers provide additional insulating qualities to a wood frame structure. C) A 1-inch (25 mm) airspace is usually constructed between the brick veneer and the wood frame. D) Brick veneers are attached to the wood frame of the structure by metal ties mortared into the courses.
A Notes) Page 94;
A, B, and C are all true, but only A is relevant to the fire service. D is incorrect. 82) What trend in the building construction industry has the negative effect of increasing the speed of structural failure in a fire? A) The use of lighter and more precise wood framing systems. B) The use of prefabricated structures. C) The move towards panelization. D) The use of plastic foam insulation and aluminum framing.
A Notes) Page 95;
2) What kind of structural system can be constructed of concrete without the benefit of steel reinforcement? A) A beam. B) An arch. C) A ceiling slab. D) A cantilevered deck.
B Notes) Page 71;
See Figure 7.1. 6) The crossection of a reinforced concrete beam is usually shaped like a : A) Box. B) "T". C) Inverted "U". D) Steel I-beam.
B Notes) Page 72;
10) Which of the following examples best describes the process of pretensioned reinforcement in a concrete beam? A) The precast beam is surcharged on the ceiling side with a heavy load until deflection is achieved in the opposite direction of the floor load. When in place, the upward deflection counteracts against the tensile forces exerted by the live load. B) Steel reinforcing strands are stretched before the concrete is poured. As the concrete cures, the tension is released on the bars which creates a compressive force in the beam. C) Steel reinforcing strands are compressed by hydraulic jacks before concrete is poured. Once the concrete cures, the jacks are released causing the bars to pull the beam taut like a rope. D) Compressed lateral reinforcing bars are used in lieu of stirrups. Once the concrete cures the jacks are removed from the laterals which create compressive forces much like that of an internal arch.
B Notes) Page 73;
14) While inspecting work on a forty-story office building, the structural engineer observes a batch of concrete being off-loaded from the mixer that appears to be "watery". How should the engineer verify that the moisture content of the mix meets the design specifications? A) Examine the bill of laden carried by the driver of the concrete mixer. B) Perform a slump test. C) Call the concrete plant operator to verify the proportion of water and the air entrainment in the mix. D) Break a test cylinder.
B Notes) Page 74;
15) Which of the following statements about cast-in-place concrete operations is FALSE? A) Construction joints between successive concrete pours is usually unavoidable when casting a large structure. B) Concrete must be wet when making successive pours to insure transfer of loads from one pour to the next. C) Reinforcement steel should overlap the joint between successive concrete pours. D) The most common method for constructing concrete bearing walls is to install a concrete frame.
B Notes) Page 74;
Pre-cast concrete was not commonly used until after World War II. Structural Systems Knightlite Software 6 20) Pre-cast frames share common construction techniques with which of the following? A) Cast-in-place building frames. B) Steel-frame buildings. C) Post and beam timber construction. D) Flat slab concrete frame buildings.
B Notes) Page 75;
27) Since a building's structural frame is often concealed by interior and exterior walls, firefighters must be able to discern the nature of the building's frame based on it's architectural style, age, or use. What type of frame would most often support a modern one- story industrial or retail store showing pre-cast concrete curtain walls? A) Pre-cast concrete. B) Steel. C) Cast-in place concrete. D) Combination of steel columns and concrete beams.
B Notes) Page 76-77;
29) In what type of steel beam and girder construction is there no deflection in the angle of the beam and column connection as loads are applied? A) "Channel steel". B) "Rigid frame". C) "Space frame". D) "Complex frame".
B Notes) Page 77;
A girder arch, a trussed steel arch or steel suspension system would be suitable framing applications for a gym. Structural Systems Knightlite Software 10 36) Which of the following frame structures would a firefighter expect to support a 300-foot wide gymnasium roof? A) Girder and beam. B) Girder arch. C) Bar joist. D) Joist girder.
B Notes) Page 80;
42) Which of the following is most effective method for resisting rotational forces that cause buckling of a steel beam in a fire? A) Installation of a waffle framework. B) Installation of rigid connections at both ends of the column. C) Installation of corbels at the beam-column connection. D) The application of solid flanged columns instead of hollow core steel columns.
B Notes) Page 81;
50) In constructing a masonry wall, what construction practice must occur as the wall increases in height? A) The walls must be shored up with metal or wood staging and diagonal reinforcement. B) The width of the base must broadened to carry the increased dead load and provide greater stability. C) The masonry units must be "soldiered" every six courses. D) Steel reinforcement must be added inside the masonry units after the fifth story or 54 feet (16.7 m).
B Notes) Page 84;
A: What happens after the staging is removed? Structural Systems Knightlite Software 14 51) "MORTAR-R-US Masons" are building a brick wall seven feet tall with two wythes. To reinforce the stability of the wall, Mason Moe suggests that a "soldier course" be laid every fourth course. Mason Larry says that a "header course" should be laid every sixth course while Mason Curly insists that a stretcher course be installed every three courses. Disagreeing with his partners, Mason Shemp is adamant that a third wythe be constructed. Who is correct? A) Mason Shemp. B) Mason Larry. C) Mason Moe. D) Mason Curly.
B Notes) Page 85;
Structural Systems Knightlite Software 17 60) Which of the following statements is INCORRECT? A) A parapet is designed to prevent the spread of fire between the roofs of closely adjacent buildings. B) A "fire cut" is designed to save the floor structure at the expense of the masonry bearing walls. C) As with timber beams, steel beams can be supported in a masonry bearing wall with "beam pockets". D) When heavy live and dead loads are anticipated, pilasters can be used to reinforce beam/ masonry wall junctions.
B Notes) Page 87-88;
It is safe to assume that in the event of a masonry wall collapse, the wall will fall a lateral distance equal to the height of the wall. It would better if the apparatus and personnel were to be located farther away, but often that is impractical for firefighting purposes. 65) You are responding to a heavily involved fire in a 8-story brick masonry wall warehouse. The aerial ladder must be deployed to make a rescue on the 6th floor. Aside from all other firefighting considerations, where would you position the aerial apparatus so that it is the least susceptible to a wall collapse while executing the rescue? A) At the rear of the building, where no parapet is showing. B) At the corner of the building. C) At the front of the building where the building cornice reinforces the roof parapet. D) At the side of the building where the firewall is strongest.
B Notes) Page 89;
The relative thinness of the hollow core concrete block makes it very susceptible to spawling in the face of fire exposure. 62) What can a firefighter deduce from observing metal thrust plates and nuts on the third story exterior wall of a 19th century brick warehouse ? A) That the structure was rehabilitated with a steel girder structural frame. B) That the structure has been rehabilitated. C) That the structure is in immanent danger of collapse and should not be entered under any circumstances. D) That the structure is highly susceptible to collapse if exposed to fire for a period exceeding 2 hours.
B Notes) Page 89;
The corners of the building always provide the most amount of support in a masonry structure and therefore are the least susceptible to collapse. Stairwells, elevator shafts, and other points of intersection also provide greater protection. Members of FDNY Ladder 6, Engine 39, and Engine 16 survived the collapse of 1 WTC in the central B stairwell adjacent to the elevator shafts. Structural Systems Knightlite Software 19 66) A log cabin is an unique example of which of the following? A) Wood being used as a framing material. B) Wood used as a solid wall material. C) Wood used as a foundation material. D) Wood used as a fire resistive material.
B Notes) Page 90;
68) Which of the following wood construction types characteristically uses 4"x 4" (100 mm x 100 mm) wood columns? A) Heavy timber framing. B) Post and beam framing. C) Light Wood framing. D) Glulam construction.
B Notes) Page 91;
See Figure 7.72a and b. Ledgers provide a convenient resting place and structural support for stringing joists. Strap fasteners are then nailed to the face of the beam or the top of the ledger to secure the joists in place. 72) A framing style in which the exterior wall studs extend continuously between the foundation and the roof is called: A) Light timber framing. B) Balloon framing. C) Platform framing. D) Stud-Turkel framing.
B Notes) Page 93;
80) Upon arriving at a fire scene at a brick and wood structure, how can a firefighter determine whether the exterior brick walls are bearing walls or just veneer? A) Veneer bricks usually measure 1/2 the width of conventional brick. B) A bearing wall will show a header course every sixth course. C) Veneer bricks are usually wire-cut and therefore show longitudinal, stratified folds on the ends. D) If the building is less than 15 years old, the brick surface is most likely a veneer.
B Notes) Page 95;
Trusses constructed of 2" x 4" rather than the traditional 2" x 12" rafter system is a good example of this trend. Although the trusses can be erected in one day, the lighter building stock and the multitude of unprotected fasteners are much more susceptible to early failure in a fire. Prefabrication and panelization behave no differently in a fire than traditional stick-built structures. Foam insulation is a problem but aluminum framing is more fire resistive than wood. 83) Which of the following statements is FALSE? A) Wood structures are distinctive from masonry or steel frame structures in that the framing is combustible and contributes to the fuel load in a fire. B) Deteriorated wood buildings pose less of a threat to firefighters since inherent moisture and rot retards fire communication. C) Fiberglass insulation does not prevent the extension of fire in the concealed spaces of a wood frame structure. D) Plumbing is a potential conduit for fire communication and extension in a wood-frame structure.
B Notes) Page 95;
See Figure 7.1 . Structural Systems Knightlite Software 2 5) What are the "stirrups" in a steel reinforced concrete beam? A) Steel eye hooks, protruding from the sides of the cast beam, that are used to lift the beam into place. B) The female portion of a "key" joint between a reinforced concrete column and a reinforced concrete floor slab. C) Vertical reinforcing bars that resist the diagonal tension. D) The horizontal reinforcing bars that are used to tie the tensile reinforcing bars.
C Notes) Page 71;
Reinforcing bars also resist compressive and bending stresses that impact the structural integrity of a concrete column. Lateral reinforcement is installed in a concrete column to prevent the vertical compressive bars from buckling. Compressive forces impact concrete columns, reinforcement is required. Structural Systems Knightlite Software 3 9) What are the recognized methods for prestressing reinforced concrete? A) Surcharging and Pretension. B) Precharging, Pretension, and Posttension. C) Pretension and Posttension. D) Pretension and Ordinary.
C Notes) Page 72-73;
Structural Systems Knightlite Software 4 12) Which type of reinforcement poses a serious hazard to firefighters sawing through concrete on a rescue? A) Ordinary reinforcement. B) Pretensioned reinforcement. C) Posttensioned reinforcing. D) Asbestos reinforcement.
C Notes) Page 73;
Slab and beam construction can employ both steel and concrete beams to support the slab. 19) Which of the following buildings would most likely be constructed of pre-cast concrete assemblies? A) Grand Central Station, New York City, circa 1913. B) U.S. Customs House Building, Portland Maine, circa 1868. C) Sears Tower, Chicago, Illinois, circa 1973. D) All of the above.
C Notes) Page 75;
Concrete curtain walls are often supported by steel frames. Most of the contemporary "big box" stores are constructed with exposed steel frames. See Figure 7.16. Structural Systems Knightlite Software 8 28) What is the term for the condition whereby the concrete rebars are visible due to prolonged radiant heat exposure? A) Glulam. B) Deformation. C) Spawl. D) Entropy.
C Notes) Page 77;
30) Which of the following forces are beam and girder frame systems susceptible to? A) Compressive forces. B) Tensile forces. C) Lateral forces. D) Vertical forces.
C Notes) Page 78;
31) Connection of a beam and a girder by the bolting of a bracket at the web of the beam is an example of which of the following steel frame systems? A) Rigid frame. B) Semi-rigid frame. C) Simple frame. D) Flexible frame.
C Notes) Page 78;
If you marked C as your answer, perhaps you should reconsider firefighting as a career path. 35) Under which of the following circumstances would an architect specify a joist girder rather than an open web joist to support a load? A) When the building is subject to wind loading. B) When the construction budget permits the use of a joist girder. C) When the joist must support heavy loads. D) Whenever masonry bearing walls are specified.
C Notes) Page 79;
The key to combating rotation is the anchoring of the column at both ends. 43) Which of the following steel column designs represents a hazard in fire situation? A) Steel columns extending over 30 feet (10 m) in height. B) A steel column braced only by angle irons at both ends. C) A steel column with a slenderness ratio of 134. D) A channel steel column welded together to form a rectangular crossection.
C Notes) Page 81;
The slenderness ratio is the UNBRACED ratio for those of you who thought B was the answer. 41) In a fire situation which of the following forces contributes most to the buckling and failure of a steel column ? A) Lateral forces. B) Tensile forces. C) Rotational forces. D) Diagonal forces.
C Notes) Page 81;
46) During the 1967 McCormack Place fire, many factors contributed to the failure of the unprotected open-web steel trusses that supported the soaring roof of this Chicago exhibition hall. No sprinkler system had been installed in the exhibition hall, the internal supply hydrants had been shut off, street hydrants malfunctioned, and the hall was jammed with flammable trade show booths and materials. From a structural standpoint, what was the principal miscalculation that the building designers made in specifying unprotected roof trusses? A) The designers failed to provide an sufficient internal standpipe system to permit an effective fire suppression response. B) The designers violated building codes by not installing an automatic sprinkler system. C) The designers assumed that the height of the building was sufficient to dissipate heat from an exhibition floor fire before it would affect the steel trusses. D) The designers should have specified steel gussets to cover the fasteners between the beams and the trusses.
C Notes) Page 83;
B: Interior masonry bearing walls provide lateral support AND vertical support. C: Cast iron columns are indicative of the 1800's not of the period between the world wars. D: There is no term "extraordinary construction" . 49) What is the practical maximum height of a building constructed with non-reinforced masonry bearing walls? A) 10 storys. B) 3 storys. C) 6 storys D) 150 feet.
C Notes) Page 84;
Structural Systems Knightlite Software 15 54) Bill, the Corporate Mogul, wants to build a nine-story brick mansion that looks like Versailles. Since he can afford to be a purist, Bill wants all load-bearing walls to be constructed of solid brick. How should the architect design the typical wall crossection to meet both Bill's objectives and sound engineering practices? A) The base should be nine wythes wide, decreasing 1 wythe for every vertical story. B) Steel frame should be constructed with an exterior plywood sheathing faced with a brick veneer. C) Reinforcing roads should be installed between the exterior and interior wythe and then the cavity filled with grout. D) Steel frame installed with a pre-cast concrete curtain wall faced with an exterior brick facade.
C Notes) Page 86;
Certainly all of the above conditions can contribute to the destabilization of a masonry wall during a fire. However, it is the collapse of the internal framing that is mostly often responsible for the destabilization of masonry walls, especially external walls. 64) When would you position fire apparatus in relation to a heavily involved masonry wall structure? A) One block away from the structure. B) A distance from the building that is equal to one half the height of the exterior wall. C) A distance from the building that is equal to the height of the exterior wall. D) A distance from the building equal to 3 times the height of the exterior wall.
C Notes) Page 89;
The application of interior tension rods (with exterior thrust plates) only indicates that the masonry walls have been shored up and probably the brick re-pointed. The application of tension rods would not generally be necessary if a steel frame were to be constructed on the interior. Structural Systems Knightlite Software 18 63) What is the principle cause for collapse of a masonry wall structure in a fire situation? A) Decomposition of masonry wall mortar when exposed to radiant heat. B) The absence of tension rod reinforcement. C) The collapse of the interior framing which eliminates internal bracing or exerts horizontal pressure on masonry walls. D) Poor maintenance of masonry walls and lack of periodic mortar repainting.
C Notes) Page 89;
When the foam fills the entire cavity oxygen availability for combustion is restricted. Structural Systems Knightlite Software 22 78) What actions can a builder take to reduce the combustibility of blown-in cellulose insulation? A) Treat the cellulose with sulfuric acid. B) Add an equal part of aluminum or magnesium shavings (chaff) to each part of cellulose insulation. C) Treat the cellulose with water-soluble mineral salts. D) Insure that electrical wiring is run outside of the wall cavity.
C Notes) Page 94;
4) In a reinforced concrete beam, how are the reinforcement bars laid to resist tensile forces? A) Diagonal to the longitudinal axis of the beam. B) Along the longitudinal axis of the beam. C) Vertical to the longitudinal axis of the beam. D) At the bottom of the beam and along its longitudinal axis.
D Notes) Page 72;
7) What is the advantage of forming concrete beams with a "T" crossection? A) Reduces the number of tension-resistant steel reinforcing bars required to support the beam. B) Reduces the need for tension reinforcing bars in the beam. C) The flange of the "T" provides greater cross-tensile strength when fastened to concrete beams on either side. D) Allows the beam to carry a greater load and while reducing the dead load of the beam.
D Notes) Page 72;
Figure 7.3 shows the amount of dead load area that is no longer carried by a concrete beam if poured in the T-configuration. 8) What direction are the reinforcing bars laid in a concrete column? A) Concrete columns do not require reinforcement since the stresses are compressive. B) Vertically in the center of the column. C) Horizontally across the crossection of the column. D) Both vertically and laterally.
D Notes) Page 72;
Posttensioned reinforcement is not bonded to the concrete and can whip out of the concrete when cut. There is no asbestos reinforcement for structural concrete. 13) What is another name for "site cast concrete"? A) "Reinforced concrete". B) "Pre-cast concrete". C) "5000 psi concrete". D) "Cast-in-place concrete".
D Notes) Page 73;
Because of the framework in a concrete waffle, the rebars are laid along the x-axis and the y- axis of the slab. 18) A poured-in-place slab supported by concrete beams and steel girders is called: A) Waffle construction. B) Steel and Slab construction. C) Flat slab frame. D) Slab and beam frame.
D Notes) Page 74;
Tee slabs are generally used in such broad clear spans. 22) What fixture can be cast into a column to help support a pre-cast concrete beam? A) Steel angle irons. B) Corbels. C) Short steel beams. D) All of the above.
D Notes) Page 75-76;
21) Which of the following pre-cast slab designs can be used in a clear span of 110 feet (34 m) ? A) Hollow-core slab. B) Solid slab. C) Waffle slab. D) Double-tee slab.
D Notes) Page 75;
25) Pre-cast concrete exhibits greater structural rigidity in a fire than cast-in-place concrete because: A) Pre-cast concrete is usually more uniform in density and composition. B) Pre-cast concrete usually contains a higher air entrainment factor thereby increasing the insulating properties of the material. C) Pre-cast concrete is lighter and therefore less susceptible to fire deterioration. D) Cast-in-place concrete is more rigid than pre-cast due to the continuity of concrete at the intersection of members.
D Notes) Page 76;
34) What structural element distinguishes a "bar joist" from other types of steel trusses? A) The chords are fabricated from steel bars. B) Bar joists can accommodate loads over spans exceeding 150 feet (46 m). C) The assembly is sprayed with corrosive-resistant polymers. These coatings were first developed to combat tobacco smoke deterioration in buildings housing drinking establishments. D) The webbing of the joist is constructed of steel bars.
D Notes) Page 79;
A cantilevered structure is an excellent application for a steel cable suspension system, along with elevated pedestrian walkways, canopies, and of course of bridges. 39) Which of the following columns exhibits the highest incidence of buckling when exposed to a fire condition? A) Cast-in-place concrete. B) Concrete block or brick. C) Wood. D) Steel.
D Notes) Page 81;
Structural Systems Knightlite Software 11 40) What is the definition of the "slenderness ratio"? A) The ratio between the height and weight of a firefighter divided by the constant of 50 pounds (the average weight of turnout gear and SCBA). B) The ratio of the braced length of a steel column to the area of its crossection. C) The ratio of the overall building height to the average length of structural columns supporting each floor. D) The ration of the unbraced length of a steel column to the area of its crossection.
D Notes) Page 81;
53) If you were to cut a crossection of a masonry building wall, what would you find being used as a bonding connection between a concrete masonry unit wythe and a brick wythe? A) Concrete masonry units. B) Brick header courses. C) A36 beams. D) Steel ties.
D Notes) Page 85;
See Figure 7.52. 52) This construction method is used on outside masonry walls to prevent water seepage into the living areas and to provide insulating properties: A) What is rigid foam insulation with aluminum facing on the inside wall? B) What is "Tyvek" vapor barrier between wythes? C) What is urea-polymer mortar amendment? D) What is the cavity between exterior and interior wythes?
D Notes) Page 85;
See Figure 7.56. The drawing shows a pediment triangle with a 90 degree apex. Other authorities state that the imaginary triangle should be equilateral. The point is that the lintel carries only a portion of the weight and assumes that the tensile strength of upper stretcher courses helps distribute the load throughout the wall. Structural Systems Knightlite Software 16 57) What element of a masonry wall is inherently weak in the face of lateral forces and mortar deterioration and can therefore pose a collapse threat to firefighters? A) Corbelled openings. B) Buttresses reinforcements C) Intersections of walls. D) Parapets.
D Notes) Page 86-87;
All three can be used, although lintels remain the most frequently applied structure. 56) How much dead load should a door lintel be designed to carry? A) The weight of the entire wall directly above the opening. B) The weight of five courses of masonry located above the lintel. C) The weight of the masonry wall directly over the lintel divided by the constant 0.562. D) The weight of a (equilateral) triangular portion of the wall directly above the lintel.
D Notes) Page 86;
Answer C illustrates the standard crossection for construction of a brick exterior wall over 6 stories in height. A: Solid brick walls should not be constructed higher than 6 storys unless reinforcement can be provided. B: Does not meet Bill's objectives of an interior and exterior brick wall. D: Does not meet Bill's objectives. Imagine trying to cut in all those windows in a pre-cast concrete? And the Palace at Versailles has a lot of windows! 55) Which of the following structures are designed to provide support over a window or door opening in a masonry wall? A) Lintel. B) Door/Window frame. C) Arch or lintel. D) Corbelling, arch, or lintel.
D Notes) Page 86;
Buttresses and wall intersections are the strongest masonry elements to lateral forces. Corbels are as inherently strong as the wall. Parapets extend above the roofline and have little or no reinforcement especially to lateral winds and drafts. Firefighters should always be wary of parapets collapsing outward onto the street or alley in a fire incident. 58) What kind of framework should a firefighter expect to encounter in a 19th century manufacturing or "mill" building? A) Steel frame. B) Open web joists. C) Nominal wood framing. D) Heavy timbers and joists.
D Notes) Page 87;
71) What is a "ledger"? A) The materials list for the construction of a building. B) An accounting book used in the building trades. C) A plate that is used to secure 2" x 4" (50 mm x 100 mm) studs to the platform of a story. D) The beam or portion of a girder upon which the ends of floor joists rest.
D Notes) Page 92;
73) Which of the following construction types provides the least avenues for fire communication? A) Balloon construction. B) Platform construction. C) Light wood construction. D) Post and timber construction.
D Notes) Page 92;
Structural Systems Knightlite Software 20 70) Lumber of nominal dimensions such as 2" x 6" and 2" x 10" (50 mm x 152 mm and 50mm x 254 mm) are associated with which of the following construction types? A) Wood truss systems. B) Post and beam construction. C) Platform framing. D) Light wood framing.
D Notes) Page 92;
76) Which of the following materials would not be considered an appropriate for use as sheathing? A) Oriented strand board (OSB). B) Plywood. C) Wood planks. D) Rigid insulation.
D Notes) Page 93;
Because post and beam construction the interior frame is left exposed, there are relatively few combustible voids. Structural Systems Knightlite Software 21 74) What is the principal disadvantage of platform framing over balloon framing? A) Platform framing offers more paths for vertical communication of fire between floors. B) Platform framing is considerably more time consuming and expensive to construct. C) Platform framing is less rigid. D) Platform framing is susceptible to greater differential vertical movement in the frame.
D Notes) Page 93;
Platform framing uses more horizontal members which are therefore more susceptible to vertical movement. Such vertical movement results in the misalignment of openings (windows and doors) and cracking of interior walls. 75) What is applied over the exterior frame of a wood structure to provide structural rigidity? A) Siding. B) Rigid insulation. C) Strapping. D) Sheathing.
D Notes) Page 93;
77) Due to its high R values and ease of installation, foam plastic insulation is popular in the building industry. However the material is combustible and poses great concern to the fire service . Which of the following applications most restricts fire communication in a foam insulated wall cavity? A) When the interior wall is faced with a fire resistive material such as gypsum board. B) When the insulation is faced with a reflective metal foil. C) When an air space at least 1-inch in width is provided between the insulation and the exterior wall. D) When the foam fills the entire wall cavity.
D Notes) Page 94;
