Lec 1

Question 1

Why materials?

Answer 1

Because a seismic resistant building foundation is construction materials. In another word, construction material is the gene of civil engineering.

Question 2

Material technologies

Answer 2

Repair & retrofit, hazar mitigation, structural safety and reliability, construction productivity, and sustainability and environmental protection.

Question 3

Concrete

Answer 3

Latin : concretus (to grow together)
Water + cement + fine aggregate (sand) + coarse aggregate
Water + cement = paste
Paste + sand = mortar

Question 4

Volume ratio of concrete

Answer 4

3/4 filler (aggregate)
1/4 paste

Question 5

What is important to the quality of concrete

Answer 5

Ratio of water / cement

Question 6

Reinforced concrete

Answer 6

Strengthen with reinforcement (belong to multiple structures)

Question 7

Why concrete + steel reinforcement?

Answer 7

1. Complementary mechanical properties (concrete: high compressive strength, low tensile strength, and brittle failure) (steel: high tensile strength and poor compressive stability)
2. temperature volume change rates are similar
3. Durability (concrete prevents steel from corrosion and fire)
4. Well bonding

Question 8

Why concrete is the most widely used material?

Answer 8

1. Cheapest and most readily available
2. Excellent resistance to water
3. Can be formed into any shapes and sizes
4. Surface can be well finished

Question 9

Reinforcement Concrete advantages and disadvantages compare to steel structures.

Answer 9

Advantages:
1. High plasticity
2. Fire resistance
3. Prevent corrosion
4. Economical
5. Durability
6. Easy to cooperate building requirements

Disadvantages:
1. Strength/weight ratio is low
2. Not fully recyclable
3. Long construction period