17. If the liquidity index (LI) is 0, the natural water content of plastic soil is equal to its a. Liquid limit b. Plasticity index c. Shrinkage limit d. Plastic limit 18. Compaction is the process of soil densification that occurs due to the a. Expulsion of air b. Expulsion of organic matter c. Expulsion of water d. All of the above 19. The zero-air-void curve can be obtained a. Through testing in the laboratory conditions b. In the field using the appropriate machinery c. It is theoretical curve that cannot be achieved in practice d. None of the above 20. In the US Quick clay is known when Sensitivity is between a. 2-4 b. 4-8 C. 10-18 d. >20 MacBook Pro 888 DD F4 F5 F8

Weight of structure W.T. Sand layer H2 Clay layer Н as Compacted sand- gravel layer figure 1

(1). What is the phenomenon of liquefaction of the soil?(2). Explain the liquefaction phenomenon of the soil body by the principle of the soil mechanics.