Stochastic productivity assessment of continuous flight auger piles

Continuous flight auger (CFA) piles are widely used in the US and the UK as well as in many other countries. This paper focuses on developing simulation models to provide productivity and cost for various pile sizes and depths. Two simulation models were developed. Based on these models, various charts were developed to assess productivity and cost of the CFA process. Results showed diat productivity is approximately 14, 24 and 93 piles (holes)/day for 0.36 m diameter piles at 21.34 m, 12.19 m, and 3.05 m depths, respectively. In addition, a pile of 0.36 m diameter and 12.19m depth costs approximately US$790.00; however, it costs approximately US$1200/pile for 21.34 m depth. For the same pile size, the cost per unit volume is approximately US$620.00/m3. The developed tools play an essential role in the CFA decision-making process. The results of simulation models are validated with an average validation factor (VF) of 1.01. This paper provides charts for practitioners' usage to schedule and price CFA pile construction projects. In addition, it provides researchers with a methodology for applying simulation to the CFA pile construction process and its limitations.