Excavating and Earthmoving

Excavation and earthmoving operations provide many opportunities for automation.  The work area is often exposed and spread out, and the nature of the work is such that it can be readily undertaken by remotely operated, mechanical means.  Automation is especially effective in the excavation and compaction of soils.  Moving materials over a project site can be conducted with the implementation of on-board computer technologies that free the operator from many tasks.  Much of the automated construction equipment available makes use of GPS technologies.

 Example Automated Technologies: 

The following are examples of automated excavation and earthmoving technologies that are currently available for use:

Common Limiting Design Features

The following are examples of design features that often limit the use of automated excavation and earthmoving technologies during construction:

• Inadequate clearance for access and operation of the equipment, especially when working in trenches and other confined excavations.

• The presence of obstructions, such as underground and aboveground utilities.

• Irregularly sloped sites and steep grades.

• Excavations with benches or other abrupt features.

• A lack of electronically available site data.

• Incompatibility of electronic site data provided with that required of automated technologies.

Recommended Design Practices

The following are examples of suggested design practices that facilitate the use of automated excavation and earthmoving technologies during construction:

Excavation/Earthmoving:

• Provide a digital copy of existing surface profiles with the construction documents.

• Locate stations within laser range for grading areas.

• Design uniformly sloped grading plans with well-defined break lines.

• Eliminate diagonal grade breaks and warped crown within five feet of the edge of the roadway.

• Minimize obstacles in the pathway of the receiver and transmitter; maintain an open grading area.

• Specify more precise standards for installing underground utilities effectively.  This is more so important with automated technologies because the operator does not get to see as much of the excavation.

• Design excavation depths to be conducive to the use of automated equipment.  Stronger pipe does not need to be buried as deep, so automation implementation may balance or lower costs through increased productivity.

• Maximize visibility between the operator and the equipment for remote-controlled equipment.

Soil Compaction:

• Allow for adequate space for the size of the equipment.

• Specify backfill material conducive to the use of automated equipment.

• Adjust trench slopes to slope within the range of the equipment.

• Adjust lift specifications to allow clearance for perpendicular objects (pipes, shoring supports, etc.).

• Use slopes in place of vertical inclines.

• Design placement and extraction points for the equipment.

• Maximize visibility between the operator and the equipment for remote-controlled equipment.

• Eliminate obstructions.  If obstructions cannot be eliminated, locate the obstructions away from compacted areas, and vice versa.

Expected Benefits

The following are examples of benefits that have been realized from the use of automated excavation and earthmoving technologies during construction:

• Increased production for excavating and moving soil.

• Reduced labor force associated with centrally-controlled, driverless haul trucks and other heavy equipment.

• Improved ability to meet grade specifications.

• Shorter time required to compact soil and greater consistency in compacted soil properties.

• Decreased worker exposure to safety and health hazards such as cave-ins and struck by heavy equipment.

 Example productivity improvements that have been realized: