(Solved): 2. As part of this highway rehabilitation project, a concrete retaining wall would be constructed ...

2. As part of this highway rehabilitation project, a concrete retaining wall would be constructed as shown below to support the bridge at this Exit 205. The construction of the retaining wall would require a backfill material from a borrow pit in Bastrop, to be brought into the excavation behind the retaining wall and it would be compacted to a final void ratio of \( 0.8 \). The soil in the borrow pit from Bastrop has a natural void ratio of \( 1.1 \). i. What volume of soil from the Bastrop borrow pit is required to construct \( 1 \mathrm{~m}^{3} \) of the compacted backfill? f the Bastrop borrow pit soil has a natural moisture content of \( 11 \% \) and \( \mathrm{G}_{\mathrm{s}} \) of \( 2.7 \). Determine: ii. The moist unit weight of the soil (from the Borrow pit). iii. The degree of saturation of the borrows soil. iv. The moist unit weight of the compacted backfill soil behind the retaining wall.