Materials Concrete and steel 2

Question 1

What is compression in building structures?

Answer 1

Compression is the force that occurs when materials are pressed or squashed. It typically occurs when weight, such as from a roof, is placed on walls or columns, causing them to bear the load.

Question 2

What is tension in building structures, and where is it commonly found?

Answer 2

Tension is the force that pulls or stretches materials. It is most commonly seen in pitched roofs, where the weight of the roof creates outward forces on the walls.

Question 3

What is torsion, and how does it affect structures?

Answer 3

Torsion is the twisting force applied to materials, causing them to rotate or deform. It occurs in structural members such as beams when subjected to uneven forces.

Question 4

What is shear load, and what causes it?

Answer 4

Shear load is a force applied that tries to slide materials in opposite directions, causing them to shear. It can be caused by high winds or earthquakes.

Question 5

What is uplift in the context of building forces?

Answer 5

Uplift is the upward force exerted by wind or other forces on a building, typically affecting the roof. It can cause damage or displace the roof structure.

Question 6

What is a cantilever load?

Answer 6

A cantilever load occurs when part of a building extends beyond its support, such as a balcony or roof overhang, requiring sufficient support and bracing.

Question 7

What are dead loads in construction?

Answer 7

Dead loads are the permanent, non-variable loads on a structure, such as the weight of the building materials themselves (e.g., roof, walls, floors).

Question 8

What are live loads in building construction?

Answer 8

Live loads are variable forces due to the weight of people, furniture, or vehicles within a building that can change over time.

Question 9

How are loads transferred through a building structure?

Answer 9

Vertical loads (like weight) move down through the roof and walls to the foundation. Horizontal loads (like wind) are transferred through bracing elements and walls to the foundation.

Question 10

What is the minimum bearing capacity of ground for construction in NZ?

Answer 10

The minimum bearing capacity for ground must be 300 kPa, and ground types like peat, sand, or expansive clay are unsuitable for building.

Question 11

What is a Land Information Memorandum (LIM), and what information does it provide?

Answer 11

A LIM is a document provided by the local council that gives information on the land, such as zoning, potential hazards (e.g., flooding), and any building permits or consents.

Question 12

What is a reinforced concrete slab, and when is it used in construction?

Answer 12

A reinforced concrete slab is a solid slab of concrete with steel reinforcement, often used on hardfill ground to provide a stable foundation for buildings.

Question 13

What is the role of piles in construction, and when are they used?

Answer 13

Piles are deep foundation elements (made of steel, timber, or concrete) used when the surface soil is unstable, providing stability by reaching deeper, stronger soil layers.

Question 14

What is deflection in construction, and why is it important?

Answer 14

Deflection refers to the bending or displacement of structural elements under load. Proper design accounts for deflection to ensure the structure remains safe and functional.

Question 15

What is the purpose of expansion joints in buildings?

Answer 15

Expansion joints are used to accommodate the movement of materials due to temperature changes, preventing cracks and structural damage.

Question 16

How can thermal mass help with energy efficiency in buildings?

Answer 16

Thermal mass helps regulate indoor temperatures by absorbing heat during the day and releasing it at night, reducing the need for heating or cooling.

Question 17

What is the process of heat transfer through conduction?

Answer 17

Conduction is the transfer of heat through direct contact, where heat flows from a warmer object to a cooler one (e.g., heat transferring from the sun into a concrete slab).

Question 18

What is convection in relation to heat transfer?

Answer 18

Convection is the transfer of heat by the movement of air or liquid. Warm air rises, and cooler air replaces it, distributing heat throughout the space.

Question 19

What materials are commonly used for underfloor insulation in buildings?

Answer 19

Common materials for underfloor insulation include polystyrene boards, fiberglass, or foam to reduce heat loss through the floor.

Question 20

What is double glazing and how does it improve energy efficiency?

Answer 20

Double glazing involves two panes of glass with an air gap in between, which improves insulation, reduces heat loss, and minimizes condensation.

Question 21

What is sound transmission class (STC), and how does it relate to building materials?

Answer 21

STC is a rating that measures the ability of materials to block airborne sound. Higher STC ratings indicate better soundproofing properties.

Question 22

How does mass affect sound transmission in buildings?

Answer 22

Denser materials, like concrete and brick, block sound more effectively, reducing sound transmission between spaces.

Question 23

What is sound absorption and how is it used in building design?

Answer 23

Sound absorption involves materials like foam, carpet, and acoustic tiles that absorb sound waves, reducing noise levels in a building.

Question 24

What is vibration isolation, and how is it used in buildings?

Answer 24

Vibration isolation involves using materials like mats or damping compounds to prevent vibrations from transmitting through floors and walls, reducing noise and disturbance.

Question 25

What is the difference between low-frequency and high-frequency noises in buildings?

Answer 25

Low-frequency sounds (e.g., machinery) are harder to block and require denser materials, while high-frequency sounds (e.g., talking) can be blocked more easily with softer, porous materials.

Question 26

How can landscaping reduce environmental sound in a building?

Answer 26

Landscaping with dense vegetation like trees or tall hedges can help absorb and block external noise, improving the sound environment.

Question 27

What is the IIC rating and how is it used in sound management?

Answer 27

IIC (Impact Insulation Class) measures the ability of a floor to block impact noise, such as footsteps. An IIC rating of 55 or higher is considered effective for sound insulation.

Question 28

What does the Building Code clause G6 refer to?

Answer 28

Clause G6 addresses airborne and impact sound transmission in buildings, setting minimum requirements for sound insulation in inter-tenancy walls, floors, and ceilings.

Question 29

What is reflection in sound management, and how is it mitigated?

Answer 29

Reflection occurs when sound bounces off hard surfaces like glass or concrete. It can be mitigated by using soft, absorbent materials like acoustic panels and foam.

Question 30

What is the role of thermal breaks in preventing condensation in aluminum windows?

Answer 30

Thermal breaks are insulating materials used in aluminum frames to prevent heat transfer and reduce the risk of condensation on the glass.