Innovations in Earthmoving Equipment: New Forms and Their Evolution

The technological advancement of earthmoving equipment during the 20th century includes the introduction of at least seven completely new forms. The purpose of this paper is to analyze the introduction of five new forms (track-type tractor, off-highway truck, wheel tractor scraper, hydraulic excavator, and loader-backhoe) and their subsequent incremental improvement. The description of innovation for each machine includes markets and the state of technology at introduction, differences of the new form, and changes during subsequent development. The major findings from this analysis are the key role of new technology for machine systems in the development of the new forms, the continued importance of each form in earthmoving markets, and the significant continued advancement of the equipment through incremental improvements. These findings are relevant for practice to assist in identifying possible improvements in equipment capability and work procedures. The results will also assist educators in courses concerning equipment capability and technical advancement and researchers in considering new equipment forms and capabilities as a part of developing new tools to model and improve equipment-intensive construction operations.