Question

From laboratory investigations, the liquid limit, plastic limit, natural moisture content and flow index of a soil specimen are obtained as 60%, 27%, 32% and 27, respectively. The corresponding toughness index and liquidity index of the soil specimen, respectively, are

• A. 0.15 and 1.22
• B. 0.19 and 6.60
• C. 1.22 and 0.15
• D. 6.60 and 0.19

Hint:

To calculate the toughness index and liquidity index, use the formulas for each index. The plasticity index is the difference between liquid limit and plastic limit.

Answer 1

The Correct Option is C

The toughness index (T_I) and liquidity index (L_I) of the soil are calculated as follows: 1. Toughness Index (T_I): The toughness index is given by: \[ T_I = \frac{\text{Plasticity Index}}{\text{Flow Index}} = \frac{\text{Liquid Limit} - \text{Plastic Limit}}{\text{Flow Index}} \] Substituting the given values: \[ T_I = \frac{60\% - 27\%}{27} = \frac{33\%}{27} = 1.22 \] 2. Liquidity Index (L_I): The liquidity index is given by: \[ L_I = \frac{\text{Natural Moisture Content} - \text{Plastic Limit}}{\text{Plasticity Index}} = \frac{32\% - 27\%}{60\% - 27\%} \] \[ L_I = \frac{5\%}{33\%} = 0.15 \] Thus, the toughness index and liquidity index are 1.22 and 0.15, respectively. Therefore, the correct answer is option (C). 
Final Answer: (C) 1.22 and 0.15