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What Is “Earthwork” in Construction?

  • May 30, 2024

High-quality projects can stand the test of time when built on a solid foundation. 

It’s critical to use earthwork — a construction process in which the ground is primed and prepped — to ensure your construction projects are stable and won’t come tumbling down. 

Earthwork can have aesthetic benefits, too. Aesthetic earthwork is the strategic placement of boulders, grading, and other types of landscaping to transform an outdoor space into an oasis.  

Because earthwork is key to construction work, you’ll need to be familiar with its scope, tools, and processes before embarking on a project.

Starting from the ground up, here’s everything you need to know about earthwork for projects large and small.

Table of Contents

1. What is Earthwork?
2. Why Soil Analysis Matters for Earthwork
3. How Different Types of Soil Affect Earthwork
4. Common Tools Used for Earthwork Construction
5. Types of Earthwork Construction Tasks
6. Planning an Earthwork Project


What is Earthwork? 

In essence, earthwork is not unlike playing in a sandbox. The goal is to remove, shape, arrange, and reinforce the soil and rocks on the earth’s surface to create a solid foundation for construction and landscaping.

Earthwork is essential for civil engineering and infrastructure projects, such as bridges and road construction, as well as for general building construction. Safety is paramount, and the importance of earthwork cannot be overlooked.

Different regions come with different climates and soil compositions. Both factors are key when deciding which reinforcements, fortifications, and adjustments are necessary for project completion.


Why Soil Analysis Matters for Earthwork

Earthwork begins with soil analysis. You can’t identify the type of earthwork needed without examining the soil’s chemistry and analyzing the region’s climate and weather patterns.

For large-scale projects, it’s common to hire a geotechnical engineer for this purpose. The engineer will drill boreholes to remove sample quantities of soil from different locations throughout the property. Next, they test the soil for moisture content and conduct compression tests to reveal its stability.  

Once soil testing is complete, engineers use the results to determine the type of reinforcements required. In some cases, the construction project may need to relocate to a new site with stabler soil. 

Soil analysis is a requirement, not an option, when erecting any type of building or engineering work. It’s important but less critical for lower-risk earthwork projects, such as landscaping.

Read About: Construction Footings: An Introduction


How Different Types of Soil Affect Earthwork

Different types of earth materials, or soil, contain elements that can pose challenges for certain projects. 

The six categories of soil are:

  1. Sand
  2. Clay
  3. Silt
  4. Loam
  5. Chalk
  6. Peat

Below, we provide a brief overview of each type. While most soil types can be excavated and reinforced, we explain which ones are best suited for building a solid foundation. For those that are not, we provide some workarounds.

Sandy

Sandy soil is challenging because it has a tendency to shift. It needs to be properly compacted, and often reinforced with a mixture of binding stabilizers such as cement or lime. These additives reduce shifting and increase the soil’s load-bearing capacity.

Clay

Clay is tricky to work with when it’s too dry or too wet. Some types of clay significantly expand when wet, only to shrink when dry. These fluctuations put pressure on the foundation and can lead to damage and instability. If this is likely to cause an issue, it’s best to replace the clay with a stabler material.

Silt

Silt is a soft, smooth, and well-draining soil. It has larger particles than clay, but is prone to expanding when wet and contracting when dry. This can shift the foundation and lead to other problems that impact the foundation’s stability. When building on silt, always use proper soil compaction and drainage techniques, as well as adequate reinforcements.

Loam

Loam — a blend of clay, sand, and silt — is the most desirable soil classification for construction. It is solid and stable, and is not susceptible to expansion and contraction when moisture levels fluctuate. 

Chalk

The texture of chalky soil can vary from clay-like to gravelly. Identify its exact consistency to understand what foundation reinforcements and measures are required. If the chalk is soft, it may need to be excavated until firmer ground is reached, or mixed with other soils to stabilize it.

Peat

Peat stands as decayed organic matter. It is spongy, soaks up and retains moisture, and has extremely low shear strength — meaning it’s not solid because the particles are not densely packed. In general, peat is unsuitable for building the surface of a foundation because of its instability.


Common Tools Used for Earthwork Construction

The equipment used for earthwork can vary depending on the size and scale of the project. Here’s an overview of the tools you need for large-scale construction projects, as well as smaller-scale projects.

Large-Scale Earthwork Projects 

Large-scale projects require heavy earthmoving equipment, such as backhoes, excavators, and bulldozers. These machines are quick and efficient tools for shifting, relocating, and compacting soil.

Backhoe Loader

A backhoe loader plows soils. Professionals also use it for uprooting stumps, moving boulders, digging, trenching, and more. They come with different attachments for different jobs.

Renting a backhoe can cost anywhere from $260 a day to $2,200 a month.

Bulldozer 

Bulldozers push soil and other materials from place to place. Use them to backfill, level ground, and work on land-grading projects. 

Depending on the job, they may require different blade attachments. Bulldozers cost around $440 to rent for a day, while a monthly rental can cost somewhere in the range of $3,400.

Dump Trucks

Dump trucks transport large amounts of materials, such as gravel or soil. The cost to rent one can range from $450 a day to $3,500 a month.

Excavators

Excavators are ideal for digging, grading, trenching, dredging, and moving materials and debris. They are available in several sizes, from mini to large, and can be used with a variety of attachments. Rental fees vary depending on the excavator’s size. Large excavators, for example, are priced similarly to bulldozers.

Motor Graders 

Motor graders are used to flatten and grade hard surfaces. They play a key role in preparing asphalt roads. Like excavators, they range from compact to large in size. Rental fees vary and are priced according to size.

Skid Steer Loader

Skid steer loaders can be used for excavating, digging, transporting soil and rock, trenching, digging, and landscaping. They are versatile and come with an array of attachments. Skid steer loaders cost anywhere from $150 for a single-day rental to $1,300 for a month-long rental.

Track Loader 

Track loaders are like skid steer loaders but use tracks instead of wheels, creating better traction. They are a superb option for earthwork in quarries or steep terrain because they can navigate rocky and muddy conditions well. Rental fees are as low as $400 a day to $4,000 a month.

Tractors

Tractors can do everything from mowing grass to moving materials. They are versatile and common in earthwork, especially for leveling, flattening, and smoothing soil. The cost to rent a tractor will depend on its size. Attachments can be equipped to achieve a variety of earthwork goals.

Trenchers

Trenchers are designed to dig trenches. They can dig steep narrow trenches, as well as trenches used for drainage or to bury pipes and cables.

Wheel Loaders

Wheel loaders have large front-bucket loaders for digging or moving heavy materials, such as soil and rock. They come with many different attachments suitable for a wide-range of jobs. The rental fee is similar to the cost of renting a bulldozer.

Small-Scale Earthwork Projects 

For smaller projects, the person wielding the tools — shovels, spades, hoes, and pickaxes — exerts all the effort. 

Pitchforks, spades, and trowels will break up and transport soil. Spades can be used for trenching while pickaxes can penetrate hard surfaces. Shovels are best for moving soil. 

Wheelbarrows are essential for transporting small quantities of soil and rock. Hoes and rakes can swiftly clear debris and even out surfaces. Augers can be used to dig holes for fences and posts.

Check Out: Achieving Flawless Surfaces in Commercial Construction with Screed Concrete


Types of Earthwork Construction Tasks       

In general, any task that involves the manipulation of soil, rock, and other earth materials is considered earthwork. Here’s a closer look at key earthwork tasks in the construction industry. 

Excavation 

Excavation is an essential part of earthwork. It begins by completely clearing trees, roots, bushes, boulders, and debris from the surface of the site. 

Below is a breakdown of the many types of excavation used in construction.

  • Topsoil excavation is the removal of surface vegetation. 
  • Earth excavation is the removal of soil. 
  • Rock excavation is the blasting and removal of rocks. 
  • Borrow excavation is the process of borrowing material from one site and using it somewhere else.
  • Footing excavation refers to excavation required for a foundation, which begins with site clearing. It includes excavating and shoring the sides of a foundation, which keeps the area safe and prevents dirt from backfilling.
  • Cut-and-fill excavation is the action of moving dirt and stone to create smooth and easy paths for roads and driveways. 
  • Channel excavation is used to create channels for water drainage.

Grading and Foundation Preparation 

Once excavation is complete, the next step is fine grading. This is the process of compacting the surface of the construction site to ensure the slope and level are correct. 

Foundation preparation includes adding drainage systems and placing the base. The base is usually gravel or concrete, depending on the project.

Backfill and Site Restoration

Once the primary foundation is in place, the excavated area can be backfilled with suitable materials. Each layer should be properly compacted to the appropriate density and load-bearing capacity, as determined by the project.

Site restoration includes the removal of all unnecessary equipment, spreading topsoil, clearing debris, and adding more landscaping features.

Landscaping and Gardening

Most landscaping projects involve some type of earthwork.

Larger projects may involve grading a steep incline and creating tiers to reinforce inclines, shoring them up against erosion or landslides. Adding boulders and other visually appealing elements can renew the look of an outdoor space.

Smaller landscape projects can be as simple as the creation of a flower garden. Other tasks include adding nutrient-dense soil to help flowers thrive, and using trowels and other tools to dig and plant brightly colored blooms.


Planning an Earthwork Project

The best way to proceed with any construction or landscaping project is to start — literally — from the ground up:

  • Defining your construction budget
  • Assessing the soil
  • Determining the type of equipment and materials needed for the size and nature of the project
  • Deciding whether to hire contractors, and what their responsibilities will be if hired

The greater the cost and magnitude of the project, the more due diligence (and expertise) required. The stakes are lower if you’re just landscaping your yard. For a major construction project, even minor mistakes or oversights can have dire consequences. 

Consider hiring construction management if this will be your first earthwork project. Take care to follow all proper safety protocols — especially when renting heavy machinery.


Conclusion

Earthwork is fundamental for almost every type of construction project. No matter your project, it’s important to know when to enlist the help of experts.  

Contact FMP Construction today to request a quote and learn more about how we can support your next construction endeavor. We provide innovative, value-added solutions to guarantee the highest quality of work. 

Up Next: What Is Involved in Sitework Construction?

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