Descriptive statistical analysis of TBM performance at Abu Hamour Tunnel Phase I

Abstract

The Abu Hamour Surface and Ground Water Drainage Tunnel Phase I is a 9.5-km-long, 3.7-m-inside-diameter storm water tunnel about 30 m below ground surface. Integral to phase I of the project are 19 access shafts on the tunnel line. The authors performed a rock mass quality assessment program combining borehole logging, shaft wall mapping, and laboratory testing. The results, including RMR and Q estimates, are presented and their relation to tunnel boring machine (TBM) performance examined. Rock mass properties and TBM operational data and charts are discussed. The paper also presents the results of a regression analysis linking the TBM penetration rate (PR) (mm/min) and field penetration index (FPI) (kN/cutter/mm/rev) with some geotechnical and operational parameters aggregated by strokes. For this purpose, simple, interpretable, and fairly strong general linear regression models were estimated. Then, a predictive neural network regression model was built and evaluated, revealing considerable predictive potential of the data.