Question

From the consolidation test data using the ‘change in void ratio’ method, the coefficient of volume change can be calculated by _____________

(a) \(m_v=-\frac{∆e}{1+e_o} \frac{1}{σ’} \)

(b) \(m_v=-\frac{∆e}{1+e_o}\)

(c) \(m_v=-\frac{∆e}{1+e_o}  \frac{10}{∆σ’}\)

(d) \(m_v=-\frac{∆e}{1+e_o}  \frac{1}{∆σ’}\)

I got this question in exam.

Enquiry is from Calculation of Voids Ratio and Coefficient of Volume Change topic in portion One Dimensional Consolidation of Geotechnical Engineering I

Answer 1

Right option is (d) \(m_v=-\frac{∆e}{1+e_o}  \frac{1}{∆σ’}\)

To elaborate: Using the change in void ratio method, the coefficient of volume change can be defined as the change in volume of a soil per unit of initial volume due to a given increase in unit pressure.

∴ \(m_v=-\frac{∆e}{1+e_o}  \frac{1}{∆σ’}.\)