PART 1
- Use the grid averaging (cross-section) method to estimate the quantity of cut and/or fill required for a 30ʹ × 30ʹ grid with the following existing elevations at its four corners: 91.67ʹ, 99.33ʹ, 93.25ʹ, and 96.33ʹ. Assume the proposed rough grade is 95.00ʹ for all four corners. (hint: the 95ʹ contour line divides the cell into two sections with equal areas)
- Estimate (in loose cubic yards) the quantity of topsoil that need to be removed and stockpiled for the above building plan. Assume 9ʺ of topsoil that need to be removed for an area extending 5ʹ beyond the building footprint in each direction. The swell factor is 15 percent.
- Estimate (in bank cubic yards) the volume of soil to be removed for the mass excavation of the basement area only of the above building plan. The foundation wall thickness is 1ʹ and the bottom of the continuous footing is 9ʹ below the rough grade level. Assume 1.5ʹ of working space on each side and an excavation slope of 1:1.
PART 2 - Estimate the formwork (in SFCA) needed for the footings and foundation walls in the basement area only of the shown building plan. The footings are 1ʹ deep and the foundation walls are 8ʹ high.
- Estimate the amount of concrete needed for the footings and foundation walls in the basement area only of the shown building plan.
- If the 6ʺ thick slab-on-grade (S.O.G.) at the south side of the building has steel reinforcement of #4 bars @12ʺ O.C. E.W., estimate the total length (in feet) and weight (in pounds) of this reinforcement (assume 10% for lap and waste - #4 bars weigh 0.668 lb/ft).
- If the reinforcement in question 3 was substituted with a welded wire mesh, how many 120 SF sheets are needed to reinforce this S.O.G. (assume 15% for lap and waste)?
Sample Solution