Exam 3 Flashcards

Question

A. GROUND SLOPES OVER ___% ARE SUBJECT TO EROSION AND ARE DIFFICULT TO BUILD ON. B. GROUND SLOPES UP TO ___% ARE USABLE FOR MOST OUT-DOOR ACTIVITIES AND RELATIVELY EASY TO BUILD ON.

Answer 1

A. 25% B. 5% 5%-10% slopes are suitable for informal outdoor activities and can be built on without too much difficulty.

Answer 2

- Subsurface drainage: Underground networks of piping conveying groundwater to a point of disposal. ex: - Surface drainage: Grading and surfacing of a site in order to divert rain and other surface water into natural drainage patterns or a municipal sewer system.

Answer 3

- Swale: shallow depressions formed by the intersection of two ground slopes, designed to direct or divert the runoff of surface water. - Catch basin: receptacles for the runoff of surface water. They have a basin or sump that retains heavy sediment before it can pass into an underground drainpipe. - Culvert: drains or channels passing under a road or walkway.

Answer 4

1. Direct gain: Collects heat directly within an interior space using a ‘storage mass” like a floor or wall. This storage mass should be 50-60% the total surface area of the space. 2. Indirect gain: Controls heat gain at the exterior skin of a building using a concrete or masonry Trombe wall; a drumwall of water-filled barrels or tubes; a sunspace; or roof pond. The absorbed solar energy moves through the wall by conduction and then to the space by radiation or convection. 3. Isolated gain: Collects and stores solar radiation (in air or water) away from the space to be heated. A natural convection loop brings warm air or water to the space and expels the cool.

Answer 5

Substructure: the vertical extension of a building above foundations. Superstructure: the underlying structure forming the foundations of a building.

Answer 6

A. NBC Part 4 - Structural Design B. NBC Part 6 - HVAC C. NBC Part 7 - Plumbing

Answer 7

A. CSA - Canadian Standards Association B. ASHRAE - American Society of Heating, Refrigerating, and Air Conditioning Engineers C. ASTM - American Society for Testing and Materials

Answer 8

Dynamic loads are applied suddenly to a structure, often with a rapid change in magnitude and point of application. - wind loads - earthquake load

Answer 9

Static loads are applied slowly to a structure without rapid fluctuations in magnitude or position. - dead loads - live loads - occupancy loads - snow loads, rain loads - settlement loads - ground pressure, water pressure - thermal stresses - impact loads (CHING 2.10)

Answer 10

Sliding, uplift, and overturning

Answer 11

Both are examples of static loads. Live load: comprise any moving or movable loads on a structure result-ing from occupancy, collected snow and water, or equipment. A live load typically acts vertically downward but may act horizontally as well to reflect the dynamic nature of a moving load. Dead load: static loads acting vertically downward on a structure, comprising the weight of the structure and the weight if building ele-ments, fixtures, and equipment permanently attached to it.

Answer 12

Columns, beams, bearing walls, slabs

Answer 13

Compression

Answer 14

A: Bending moment

Answer 15

Diagram should be a triangle Forces diagram /\ [___\/____]/\

Answer 16

arc up and crossing be then curbing back up to beam end point

Answer 17

Buckling and crushing. Long, slender columns are subject to failure by buckling. Short, thick columns are subject to failure by crushing.

Answer 18

Bending, deflection, and shear.

Answer 19

Shear wall: A wood, concrete, or masonry wall capable of resisting changes in shape and transferring lateral loads to the ground foundation. Rigid frame: a steel or reinforced concrete frame with rigid joints capable of resisting changes in angular relationships. Braced frame: a timber or steel frame braced with diagonal members (including knee bracing, cross bracing, k-brace)

Answer 20

Desctructive resonance is the destruction of a building or component by induced vibrations at a system’s resonance frequency, which causes it to oscillate. Caused by wind or earthquake forces. Mitigated with the use of damping mechanisms. Damping mechanisms are viscoelastic devices that are installed at structural joints to absorb oscillations and vibrations. Examples: tuned mass damper (attached in the upper portion of a tall building to prevent movement), base isolation (isolated the base of the building with dampers

Answer 21

A: Hydrostatic loads and live loads are not dead loads.

Answer 22

Linear and surface connections resist rotation. Point connections do not resist rotation unless a series of them are distributed across a large area. Point connection: bolt Line connection: weld Surface connection: glue

Answer 23

- Bearing walls - Columns - Piers

Answer 24

- Carry the live loads and dead loads acting vertically on the superstructure. - Anchor the superstructure against wind induced sliding, overturning, and uplift. - Withstand sudden ground movement (as during earthquakes). - Resist pressure imposed by surrounding soil mass and groundwater on basement walls.

Answer 25

Differential settlement is the relative movement of different parts of the structure caused by uneven consolidation of the foundation soil.

Answer 26

- Building loads (pattern and magnitude) - Subsurface and groundwater conditions, bearing capacity of soil - Topography of the site - Impact on adjacent properties - Building code requirements - Construction method and risks

Answer 27

Spread footings: The lowest part of a shallow foundation. They are extended laterally to distribute there load over an area of soil wide enough that the allowable bearing capacity of the soil is not exceeded. Two most common types are: Strip footings - continuous footings along foundation walls. Isolated footings - isolated footings at the base of columns or pier.

Answer 28

Frost line: the average depth at which soil is frozen or frost penetrates the ground.

Answer 29

- provide support for the superstructure above - enclose basement or crawl space - resist active earth pressure and anchor the superstructure against wind and seismic forces.

Answer 30

- Dampproofing and/or waterproofing on the foundation walls. - Drainage mat or gravel backfill to direct water to footing drains. - Footing drains (perforated pipe or drain tile) - Filler or sealants used at expansion joints between foundation walls and slab.

Answer 31

Stainless steel or hot-dipped zinc coated steel. Pressure treated wood.

Answer 32

Expansion joints/isolation joints

Answer 33

Control joints.

Answer 34

- Pile foundations - Caisson foundations May be used when building on unsuitable or unstable soil

Answer 35

Compression

Answer 36

A. Live loads - people, furnishings, and movable equipment Dead loads - the weight of the floor construction itself B. Beams and joists overlaid with sheathing or decking (wood, steel, or concrete) Slab (concrete

Answer 37

A. Vertical dead and live loads Horizontal wind loads and seismic loads B. Structural frames (concrete, timber, steel) Concrete or masonry bearing walls Metal and wood stud walls

Answer 38

Steel decking on steel beams or steel decking on open web joists on beams steel beams supported by girders, columns, or load-bearing walls

Answer 39

A. One-way slab is most suitable for light to moderate loads over relatively short spans (6’ to 18’) B. Two-way slab is most efficient when spanning square or nearly square bays, and suitable for carrying intermediate to heavy loads over 15’ to 40’ spans.

Answer 40

Two-way flat plate. A concrete slab of uniform thickness reinforced in two or more directions and supported directly by columns without beams or girders.

Answer 41

Punching shear is the potentially high shearing stress developed by the reactive force of a column on a reinforced concrete slab.

Answer 42

Prestressed concrete is reinforced by pretensioning or posttensioning high strength steel tendons within their elastic limit to actively resist a service load. Pretensioning prestresses a concrete member by stretching the rein-forcing tendons before the concrete is cast. Postensioning is the prestressing of a concrete member by tensioning the reinforcing tendons after the concrete has set/

Answer 43

The tensile stresses in the tendons are transferred to the concrete, placing the entire cross section of the flexural member in compression. The resulting compressive stresses counteract the tensile bending stresses from the applied load, enabling the prestressed member to deflect less, carry a greater load, or span a greater distance than a conventionally reinforced member of the same size, proportion, and weight

Answer 44

Temporary supports used to support beam and slab concrete forms until the concrete can cure and support itself.

Answer 45

Solid flat slabs Hollow core slabs Single Tees and double tees

Answer 46

- Structural steel is difficult to work on-site and is normally cut, shaped, and drilled in a fabrication shop. This can result in relatively fast construction time. - Structural steel loses strength rapidly in fire and must be covered for fire-resistance. - In exposed conditions, corrosion resistance is required. - Steel framing is most efficient when the girder and beam supports are laid out along a regular grid.

Answer 47

One-way beam system: Beams on girders Two-way beam system: primary beams on secondary beams on steel trusses (long-spanning member)

Answer 48

A: Wide-flange (W shape) beam

Answer 49

- Moment connections - Shear connections - Semi-rigid connections

Answer 50

A. Open-web joists B. K-series joists

Answer 51

- They permit the passage of mechanical services. - Light weight - Long spans - Prefabricated which may result in - -relatively fast construction.

Answer 52

A: To increase it’s stiffness and spanning capability.

Answer 53

- Members are lighter and more dimensionally stable than wood and can span longer distances. - Conduct more heat and require more energy to process than wood. - Can be easily cut and assembled on site. - Framing contains cavities for utilities and thermal insulation. - Wide range of potential finishes.

Answer 54

Wood is most susceptible to shrinkage perpendicular to the grain.

Answer 55

- Lumber species - Structural grade - Modulus of elasticity - the minimum deflection permited for the intended use.

Answer 56

Continuous spans produce more uniform stresses than simple spans, resulting in more efficient use of material.

Answer 57

The elimination of costs associated with constructing and strip-ping vertical wall forms.

Answer 58

A wythe is a continuous vertical section of a wall that is one masonry unit thick.

Answer 59

- The cavity space enhances the thermal insulation value of the wall and permits the installation of additional thermal insulation material. - The air space acts as a barrier against water penetration if the cavity is kept clean, and if adequate weep holes and flashing are provided.

Answer 60

Clay masonry units tend to absorb water and expand. Concrete masonry units usually shrink as they dry.

Answer 61

Control joints are constructed to open slightly to accommodate shrinkage of a concrete masonry wall as it dries after construction. Expansion joints are continuous, unobstructed slots construct-ed to close slightly to accommodate the moisture expansion of brick and stone masonry surfaces.

Answer 62

Hot rolled steel is less precise due to the shrinkage that occurs during cooling. Flexible and strong. Cold-formed steel is essentially hot rolled steel that gets formed after cooling. Better finish, tolerance, and more precise than hot rolled steel. Small, lightweight units. Decreased ductility (less flexible than hot rolled).

Answer 63

Slenderness ration determines the allowable load on a column. In L/r, ‘L ‘is the unsupported length of the column in inches and ‘r’ is the least radius of gyration for the cross section of the column. As the slenderness ratio increases, a column can fail from buckling.

Answer 64

Resistance to lateral wind and seismic forces requires the use of rigid shear walls or diagonal bracing.

Answer 65

Balloon framing utilizes studs that rise the full height of the frame from sill plate to roof plate. Platform framing is a light wood frame having studs only one story high, regardless of the stories built.

Answer 66

Connector should be galvanized or plated to resist corrosion.

Answer 67

1:50 (1/4” per foot)

Answer 68

Roof is the location with the greatest temperature differential, and so ventilation should be provided to prevent condensation.

Answer 69

- Strength, elasticity, and stiffness - Dimensional stability as it responds to changes in temperature and moisture content. - Resistance of a material to water and water vapor. - Thermal conductivity - A material’s transmission, reflection, or absorption of visible light and radiant heat. - Density or hardness of a material determines durability/ resistance to wear and abrasion. - The ability of a material to resist combustion, and withstand exposure to fire. - Colour, texture, and scale. - Standard sizes. - Embodied energy

Answer 70

Elasticity is the ability of a material to deform under stress - bend, stretch, or compress - and return to it’s original shape when the applied stress is removed. Every material has an elastic limit beyond which it will break or deform. The most effective structural materials are those that combine elasticity with stiffness.

Answer 71

Stiffness is a measure of the extent to which an elastic body resists deformation. The stiffness of a solid body is dependent on its structural shape as well as the elasticity of its material and is an important factor when considering the relationship between span and deflection under loading.

Answer 72

- Concrete is a mix of cement, mineral aggregates, and water. - Concrete is inherently strong in compression, and weaker in tension and shear. - Steel reinforcement is required to handle tensile and shear stresses.

Answer 73

Pros: - Can be formed into almost any shape - Variety of surface finishes and textures - Inherent fire-resistance Cons: - Heavy - Forming, molding, time required before it can be placed to set and cure. - Requires reinforcement. - High embodied carbon (CHING 12.04)

Answer 74

- Steel refers to any of various iron-based alloys having a carbon content less than that of cast iron and more than that of wrought iron. Strength, hardness, and elasticity varies depending on composition and heat treatment. Steel combines high strength and stiffness with elasticity.

Answer 75

- Steel that is painted, galvanized, or chemically treated. - Stainless steel - Aluminum - Copper - Lead - Brass

Answer 76

Contact with red cedar in the presence of moisture will cause premature discoloration of the copper.

Answer 77

are must be taken to insulate aluminum from contact with other metals to prevent galvanic action. It should also be isolated from alkaline materials such as wet concrete, mortar, and plaster.

Answer 78

Galvanic action can occur between two dissimilar metals when enough moisture is present for electric current to flow. This electric current will tend to corrode one metal while plating the other. The severity of the galvanic action depends on how far apart the two metals are on the galvanic series table.

Answer 79

Grain direction is the major determining factor in the use of wood as a structural material. Also, the manner in which the lumber is cut from the log. Tensile and compressive forces are best handled by wood in a direction parallel to the grain. Tensile forces perpendicular to the grain will cause the wood to split. The shear strength of wood is greater across its grain than parallel to its grain. It is therefor more susceptible to horizontal shear than vertical shear.

Answer 80

- Because of their relative strength and dimensional stability, mass timber products offer low carbon alternatives to steel, concrete and masonry. - Wood is a renewable and sustainable resource. - Mass timber panels are capable of heights and spans that once required steel or concrete. - Prefabrication allows for faster construction with fewer deliveries and less labour. - Structural elements may be left exposed on the interior. - Large timbers are naturally fire resistant due to the insulating layer of char that develops as the wood burns.

Answer 81

Tempered glass is annealed glass (cooled slowly to relieve internal stresses) that is reheated to just below the softening point and the rapidly cooled to induce compressive stresses in the surfaces and edges of the glass and tensile stresses in the interior. Tempered glass has three to five times the resistance of annealed glass to impact and thermal stresses but cannot be altered after fabrication. When fractured, it breaks into relatively harmless pebble-sized particles.

Answer 82

Laminated glass (or safety glass) consists of two or more plies of flat glass bonded under heat and pressure to interlayers of polyvinyl butyr-al resin that retains the fragments if the glass is broken.

Answer 83

Insulated glass is a glass unit consisting of two or more sheets of glass separated by a hermetically sealed air space to provide thermal insulation and restrict condensation.

Answer 84

Low-E Glass or low-emissivity glass, transmits visible light while selectively reflecting the longer wavelengths of radiant heat, pro-duced by depositing a low-e coating either on the glass itself or over a transparent plastic film suspending in the sealed air space of insulating glass.

Answer 85

- Hot-dipped galvanized steel - Aluminum alloy

Answer 86

- Natural covering protects the waterproof membrane from daily temperature fluctuations and the ultraviolet radiation of the sun that breaks down conven-tional roofing systems. - Conserves a permeable area that would otherwise be replaced by the build-ings footprint. - Controls the volume of stormwater runoff - Improves air and water quality - Helps reduce the heat island effect - Increases the insulation value of the roof and stabilizes indoor air temperatures and humidity, potentially reducing operating costs to heat and cool the building.

Answer 87

True. To avoid possible galvanic action.

Answer 88

- Built-up roofing systems - Single-ply roofing systems

Answer 89

Vapor retarder impedes the passage of water vapor. It should be placed on the warm side of the assembly. The temperature of the vapor retarder should be warmer than the dew point temperature to prevent condensation from occurring.

Answer 90

Single-ply membrane roofing - fully adhered system. The membrane is fully adhered with binding adhesive

Answer 91

- Aluminum - Copper - Painted galvanized steel - Stainless steel - Zinc alloy - Terne metal - Copper clad lead

Answer 92

Capillary action is a manifestation of surface tension by which the greater adhesion of a liquid to a solid surface than the internal cohesion of the liquid itself causes the liquid to be elevated against a vertical surface.

Answer 93

- Kinetic energy of raindrops - Gravity flow - Surface tension - Pressure differential

Answer 94

- Mass wall systems - Barrier wall systems such as EIFS walls - Drainage walls - Rainscreen walls

Answer 95

Rainscreen walls consist of an outer layer of cladding (the rainscreen), an air cavity, and a drainage plane on a rigid, water resistant, and air-tight support wall. 1. Cladding sheds most of the rain. 2. Air cavity serves as drainage layer to remove any water that may penetrate the outer cladding layer. Air cavity also serves as a place for the equalization of air pressure. 3. Air-barrier contains joints and seals and controls the flow of air through the wall. Can be placed on either side of the insulation. 4. Thermal insulation placed on the indoor side of the air cavity.

Answer 96

Thermal break is an element of low thermal conductivity placed in an assembly to reduce or prevent the flow of thermal energy between conductive materials. Often incorporated in window frames, a thermal break is needed where a highly conductive material, such as metal, goes from the interior to the exterior. Thermal breaks in metal window frames are more important for decreasing the likelihood of condensation than for retarding thermal transfer. Thermal bridge is the opposite of a thermal break.

Answer 97

R-value is a measure of thermal resistance of a given material. It is expressed as the temperature difference required to cause heat to flow through a unit area of material at the rate of one heat unit per hour. Rt is the total thermal resistance for a construction assembly and is equal to the sum of the individual R-values of the component materials. The R-Value for a component or assembly is the reciprocal of it's U-value. The higher the R-Value, the better.

Answer 98

U-value is a measure of the thermal transmittance of a building com-ponent or assembly. It is expressed as the rate of heat transfer through a unit area of a building component or assembly caused by a difference of one degree between the air temperatures on the two sides of the component or assembly. The U-value of a component or assembly is the reciprocal of its R-value. The lower the U-value, the better.

Answer 99

Batt insulation Rigid foam insulation Foamed-in-place insulation Loose-fill insulation Reflective insulation

Answer 100

Fiberglass or Rock wool (mineral wool) For installation between studs, joists, rafters, or furring. Non-combustible.

Answer 101

Cellular glass, polystyrene, polyurethane Boards may be applied over roof deck, over wall framing as sheathing, in cavity walls, or beneath an interior finish material. Polystyrene can come in contact with the earth. The plastics are combustible and give of toxic fumes when burned.

Answer 102

- Thermal resistance of construction assembly (total R-value) - Surface colour and reflectivity. Light colours and shiny surfaces tend to reflect more thermal radiation than dark, textured ones. - The mass of the assembly - The orientation of the exterior surfaces of the building. - Latent heat sources and heat gain from the occupants, lighting, and equipment within a building. - Proper installation of thermal insulation and vapor retarders.

Answer 103

Dew point is the temperature at which vapor condenses. In other words, is the point at which air must be cooled to become saturated with water vapor. If moisture vapor comes into contact with a cool surface whose temperature is at or below the dew point of the air, it will condense.

Answer 104

- Moisture vapor must be prevented from penetrating the enclosed spaces of exterior construction with the use of vapor retarders or - be allowed to escape by means of ventilation, before it can condense into liquid.

Answer 105

Warm air is capable of holding more moisture vapor and has a higher dew point than cooler air.

Answer 106

These are examples of materials that can perform as air barrier, vapor retarder, and WRB (water resistive barrier).

Answer 107

Vapor retarders are intended to prevent water vapor from passing through breathable building materials and potentially condensing within a construction assembly. A vapor retarder slows vapor flow by diffusion. A small crack here an there is less important than with an air barrier system. A 95% complete vapor retarder will stop 95% of vapour from diffusing through the wall. Most often on the warm side of the assembly, depending on climate. Air barriers are installed to stop the movement of air caused by differences in air pressure between the interior and exterior of the building. To stop air movement, the air barrier must system must be complete throughout the entire envelope, with minimum cracks. Air barriers can be placed anywhere in the assembly.

Answer 108

A: Vapor retarder.

Answer 109

The movement of vapor by diffusion through an assembly from areas of high pressure to areas of low pressure. The vapour drive may be from the interior to the exterior during one season and then reverse during another season. Diffusion is dependent on air temperature and the concentration of water vapor in the air. As the amount of

Answer 110

If the air barrier system is also a vapor retarder, it must be on the 'warm' side of the wall.

Answer 111

Polyethylene, sealed Peel-and-stick Asphalt sheet membrane and fluid applied membrane. Building paper is not a vapor retarder so it is suitable for all climates

Answer 112

"the Gore-Text of the building industry" Tyvek is the most well know building wrap, a water barrier and air barrier system. It works on the same principle as Gore-Tex. Stops wind and water from outside and allows water vapor created inside to escape.

Answer 113

Heat Recovery Ventilators (HRV) use a heat-exchange core to transfer heat from the exhaust air stream to the prefiltered fresh air stream in the winter and during the summer, cool the prefiltered fresh air stream with the exhaust air stream.

Answer 114

Expansion Joints: continuous, unobstructed slots constructed between two parts of a building or structure permitting thermal or moisture expansion to occur without damage to either part. Control Joints: continuous grooves or separations formed in concrete ground slabs and concrete masonry walls to form a plane of weakness and thus regulate the location and amount of cracking resulting from drying shrinkage, thermal stresses, or structural movement. Isolation Joints: divides a large or geometrically complex structure into sections so that differential movement can occur between the parts.

Answer 115

- Where a new building meets an existing structure. - Long surface areas. - Surfaces with severe solar exposure. - Parapet walls. - Long, linear building elements. - Horizontal and vertical discontinuities in the massing of a building (such as where a low mass meets a tall mass).

Answer 116

Conduction: Transfer of heat through direct contact. Convection: Transfer of heat through liquid or gas. Radiation: Transfer of heat energy in the form of electromagnetic waves from a warm body to a cool body. Evaporation: Transfer of heat through evaporation. Heat is required for the evaporative process of converting body moisture into vapor.

Answer 117

True. Darker colours absorb heat and radiate

Answer 118

- Diameter of pipe - Distance of water flow - Number of valves, tees, and elbow fittings. Runs should be as direct and straight as possible.

Answer 119

Wet Pipe System Contain water at sufficient pressure to provide an immediate, continuous discharge through sprinkler heads that open automatically in the event of a fire. Dry Pipe System Contain pressurized air that is released when a sprinkler head opens, allowing water to flow through the pipe and out the open nozzle. Often used where pipes are subject to freezing.

Answer 120

Greywater refers to the wastewater from sinks, baths, showers, and dishwashers, which can be treated and recycled for such used as toilet flushing and irrigation.

Answer 121

Transmission Loss (TL) is a measure of the performance of a building material or construction assembly in preventing the transmission of airborne sound.

Answer 122

Sound Transmission Class (STC) is a single-number rating of the per-formance of a building material or construction assembly in preventing the transmission of airborne sound, derived by comparing the labora-tory TL test curve for the material or assembly to a standard frequency curve. The higher the STC rating, the greater the sound-isolating value of the material or construction.

Answer 123

1. Separation into layers 2. Mass 3. Absorptive capacity Also: staggered studs, resilient mounting, air spaces, sealed pipe pen-etrations, and air ducts should be baffled. Heavier, more dense bodies have a greater resistance to sound transmission.

Answer 124

Acoustical ratings (or STC rating) for assemblies decrease with decreasing depth and decreasing separation of the structural members.

Answer 125

Sound Transmission Class (or STC) is an integer rating of how well a building partition attenuates airborne sound. STC is roughly the decibel reduction in noise a partition can provide, abbreviated 'dB'. The dB scale is a logarithmic one and the human ear perceives a 10dB reduction in sound as roughly halving the volume - a 40 dB noise subjectively seems half as loud as a 50 dB one. Similarly, a wall with an STC of 63 is perceived by the human ear to be 88% quieter or allow 1/8 as much perceived sound through than a wall with an STC of 33. From 33 to 43 sound is halved (1/2), from 43 to 53 it's halved again (1/4), from 53 to 63 it's halved yet again (1/8).

Answer 126

* Bidding Requirements * Contract Forms * Contract Conditions * Specifications * Drawings * Addendum * Contract Modifications

Answer 127

Be brief and clear use imperative style address instructions to the contractor avoid repetition, specifying anything which is not to be enforced, "or equal" phrases, "scope" or "scope of work" paragraphs, weasel paragraphs.

Exam 3 Flashcards

(156 cards)