In order to increase job-site productivity, it is beneficial to select equipment with proper characteristics and a size most suitable for the work conditions at a construction site. In excavation for building construction, for examples, factors that could affect the selection of excavators include:
1. Size of the job: Larger volumes of excavation will require larger excavators, or smaller excavators in greater number.
2. Activity time constraints: Shortage of time for excavation may force contractors to increase the size or numbers of equipment for activities related to excavation.
3. Availability of equipment: Productivity of excavation activities will diminish if the equipment used to perform them is available but not the most adequate.
4. Cost of transportation of equipment: This cost depends on the size of the job, the distance of transportation, and the means of transportation.
5. Type of excavation: Principal types of excavation in building projects are cut and/or fill, excavation massive, and excavation for the elements of foundation. The most adequate equipment to perform one of these activities is not the most adequate to perform the others.
6. Soil characteristics: The type and condition of the soil is important when choosing the most adequate equipment since each piece of equipment has different outputs for different soils. Moreover, one excavation pit could have different soils at different stratums.
7. Geometric characteristics of elements to be excavated: Functional characteristics of different types of equipment makes such considerations necessary.
8. Space constraints: The performance of equipment is influenced by the spatial limitations for the movement of excavators.
9. Characteristics of haul units: The size of an excavator will depend on the haul units if there is a constraint on the size and/or number of these units.
10. Location of dumping areas: The distance between the construction site and dumping areas could be relevant not only for selecting the type and number of haulers, but also the type of excavators.
11. Weather and temperature: Rain, snow and severe temperature conditions affect the job-site productivity of labor and equipment.