Earthworks Examples and Applications

A project requires $10,000 \text{ m}^3$ of compacted fill (embankment). The soil has a shrinkage factor of $0.90$ (from Bank to Compacted). How many Bank cubic meters must be excavated?

Using the bank volume calculated previously ($11,111.11 \text{ m}^3$), determine the loose volume that must be hauled if the soil has a swell of $25\%$.

Using the previous example where $13,888.89 \text{ LCM}$ must be hauled, if each dump truck carries $15 \text{ m}^3$ (loose volume), how many truck trips are required?

A highway section has a cut volume of $4,000 \text{ BCM}$ (Bank Cubic Meters) and a fill requirement of $5,500 \text{ CCM}$ (Compacted Cubic Meters). The soil has a shrinkage factor of $0.85$. Calculate the net balance of earthwork. Do we need to borrow soil or waste soil?

An excavation must reach a depth of $6.00 \text{ m}$ in dry sand. The angle of repose for dry sand is $34^\circ$. What is the minimum required horizontal setback from the top edge of the excavation to ensure the side slopes do not collapse (assuming no shoring is used)?

A soil sample has a wet density of $1,950 \text{ kg/m}^3$ and a moisture content of $12.5\%$. Calculate the dry density of the soil.

A $50 \text{ m}$ section of a proposed road has a cut area of $24 \text{ m}^2$ at station $0+000$ and a cut area of $36 \text{ m}^2$ at station $0+050$. Calculate the volume of earth to be excavated using the average end area method.

For a more accurate calculation of a $100 \text{ m}$ road section, the areas at the start, middle, and end are evaluated. The cut area at $0+000$ is $20 \text{ m}^2$, at $0+050$ (middle) is $32 \text{ m}^2$, and at $0+100$ is $40 \text{ m}^2$. Calculate the volume using the Prismoidal Formula.

An excavator has a bucket capacity of $1.5 \text{ m}^3$. The fill factor for the soil is $0.80$. The cycle time for the excavator is $30 \text{ seconds}$, and it operates for $50 \text{ minutes}$ per hour (efficiency factor of $50/60$). Calculate the hourly production rate in loose cubic meters per hour.

An excavator produces $120 \text{ LCM/hr}$. Dump trucks being used each have a capacity of $15 \text{ LCM}$ and an average round-trip travel time of $45 \text{ minutes}$. Assuming an efficiency of $50 \text{ min/hr}$ for the trucks, determine the number of trucks required to keep the excavator operating continuously.

A contractor is excavating a large basement in a tight urban environment. The original design estimated the required excavation at $5,000 \text{ BCM}$ of dense clay. However, the project manager failed to account for the soil's $30\%$ swell factor when ordering trucks. What are the logistical consequences of this oversight?

A 10-kilometer highway project has rolling terrain. The mass haul diagram shows a large deficit of fill material in the first 5 kilometers and a massive surplus of cut material in the last 5 kilometers. The contractor considers hauling the surplus from km 5-10 to fill the deficit at km 0-5. What factors must be evaluated before proceeding with this plan?

A utility trench needs to be excavated to a depth of $4.5 \text{ m}$ to install a new sewer line. The site is located in an existing roadway with adjacent buildings and active traffic lanes. The soil is a mix of loose sand and gravel. Why is sloping or benching not a viable option for this excavation, and what must be done instead?

During the construction of an earthen dam, the quality control inspector notes that the contractor is struggling to reach the required $95\%$ of standard Proctor maximum dry density. The soil being compacted is a clayey silt. The contractor is using heavy sheepsfoot rollers and making numerous passes, but the density is not improving. What is the most likely cause, and how should it be resolved?