Question

Based on research, list (3) specific considerations for use of steel, reinforced concrete (precast or site-cast), OR wood structural elements in design. In other words, list specific situations in which a particular material would be a good or bad choice.

Don’t simply list a characteristic of the material.

Be careful to describe in what specific situation, building type, or project type that particular characteristic would be beneficial or detrimental.

For example: When using precast concrete, you must have adequate laydown space to store components between the time they’re delivered to the site and lifted into place. Therefore, precast might not be a good option for very tight/cramped or sloping construction sites.

Answer 1

STEEL:

As a good choice:

1. Versatile - Steel having versatility is great because with this property of steel, exploring ideas and artistic imaginations are easy now. Most of versatile design of large, clear span buildings such as airport, terminal buildings, auditorium, warehouses, and indoor areas are built with steel.

2. Fire Resistance : Steel are highly fire resistant as compared to other material that's why there is a very less possibility of Fire accidents.

As a Bad choice:

1. Fatigue: Steel structures are quite susceptible to fatigue. It is also prone to brittle fracture when it loses its ductility. To can reduce this by adding expensive steel columns.

2. High Maintenance: Steel may get corrosion due to aggressive environment so to prevent this we need expensive paints. Also the initial cost of steel is higher than other materials which again increases the cost.

REINFORCED CONCRETE:

As a good choice:

1. Fire resistant: Reinforced concrete has a great resistance to fire too. Tthe effects of fire will be lesser if a proper cover for reinforcing steel is provided.

2. Aesthetic Independence: Concrete can be mold into required shapes and sizes.

As a Bad Choice:

1. In a  multi-storied building the RCC column section is larger than steel section as the compressive strength is lower in the case of RCC. Therefore area need is also bigger.

2. Heavy weight of concrete limits span length. Therefore to not get a higher bending moment, span length is limited in case of RCC.

WOOD

As a good choice :

1. A great heat resistant at a certain moisture content (7% to 11%).

2. Beauty and Aesthetic looks: Woods are available in  wide variety with range of aesthetic options. Also Wood absorbs sound better than any material which do nothing but enhances the comfort of living.

As a bad choice:

1. Wood will expand and contract with different seasons also it requires refinishing occasionally.

2. Also can't use it in wet areas because of bulking problems due to absorption. And also it can burn easily so not good for dry areas too where there is a chance of wild fire.