Vertical Scale (ft) 0 50 100 150 200 Slurry wall excavation, 3ft width 150 ft Layer 1 Layer 2 - Rock 95 ft Given informa
Posted: Mon Jul 11, 2022 10:11 am
- Vertical Scale Ft 0 50 100 150 200 Slurry Wall Excavation 3ft Width 150 Ft Layer 1 Layer 2 Rock 95 Ft Given Informa 1 (48.18 KiB) Viewed 36 times
- Vertical Scale Ft 0 50 100 150 200 Slurry Wall Excavation 3ft Width 150 Ft Layer 1 Layer 2 Rock 95 Ft Given Informa 2 (122.95 KiB) Viewed 36 times
a. For Layer 1, determine e, Y, Yd, and w. (16 pts) b. The contractor needs to haul the excavated soil to a disposal facility several miles away. Trucks with two rear axles (called a "tandem" for short - see picture at right) will be used. These can hold 12 cubic yards of soil that is placed in the bed using the clamshell bucket used for slurry trench excavation. A big question faced by the contractor at the time of estimating the project's price is: How many truckloads will it take to remove the excavated soil from the site? While we could complete this calculation using weight-volume relationships directly, it is common in construction practice to use a Swell Factor. The swell factor is greater than 1.0 and is calculated as follows: Swell Factor = Loose Volume Bank Volume A soil's swell factor reflects the reality that the same amount of soil occupies more volume in the truck (loose volume) than it does in the ground when undisturbed, before excavating ("bank" volume). "Swell" in this case, is a layman's term for the increase in volume caused by the excavation of soil. Physically, the act of excavation breaks up the soil into assemblages of various sizes (clods). This creates more air pockets and results in an effective increase in the soil's void volume. An increase in volume results in a corresponding decrease in unit weight. The amount of change varies for soils with different classifications. Assume that your company's laboratory conducted some field tests to determine the swell factor by excavating the in-place soil of known unit weight (from part (a)) with the slurry trench clamshell and then placing the loose soil in containers of known volume that are subsequently weighed on a large scale. The average total unit weight of excavated moist soil over all trials for Layer 1 is 94 pcf. (15pts) 1. What is the swell factor (expressed as a decimal)? 2. How many truckloads will it take to remove all of the excavated soil? 3. What does a full truckload of Layer 1 soil weigh?