Question

If the value of fck is 100 then what will be the modulus of elasticity?

(a) 5000

(b) 500

(c) 50000

(d) 50

I had been asked this question in final exam.

My enquiry is from Elastic Properties of Aggregates in chapter Elasticity, Creep and Shrinkage of Concrete Technology

Answer 1

The modulus of elasticity (E) for concrete can be estimated using the formula:

E=5000×fckE = 5000 \times \sqrt{f_{ck}}E=5000×fck​​

Where:

• fckf_{ck}fck​ is the characteristic compressive strength of concrete in MPa.

Given that fck=100f_{ck} = 100fck​=100, we can calculate:

E=5000×100=5000×10=50,000 MPaE = 5000 \times \sqrt{100} = 5000 \times 10 = 50,000 \, \text{MPa}E=5000×100​=5000×10=50,000MPa

So, the correct answer is:

(c) 50000

This value is a typical estimate for concrete with a compressive strength of 100 MPa.