Answer Happy

Figure Q3 shows the layer of sand and clay soil. It was observed that the unit weight of the sand and clay layer is 17.5kN/m3 and 18.5kN/m3 respectively. The in situ void ratio for the clay layer is 0.7. Given the load due to structure is 115kPa. The collected data from the laboratory consolidation test is as shown in Table Q3.
(a) Make necessary calculations and draw an e versus logσ′ curve based on given data in Table Q3. Given the dry mass of specimen =110 g, the height of specimen at the beginning of the test =25 mm, specific gravity =2.7 and specimen surface area =32 cm2. (10 marks) (b) Determine pre-consolidation pressure, compression index and swell index by referring to the curve obtained from Q1 (a). (6 marks) (c) Determine the settlement of the clay layer caused by primary consolidation if the clay is over consolidated. Use Cc​ and Cs​ that obtained from Q1 (b).
Table Q3: Laboratory consolidation test data