Model for Schedule Risk Evaluation in Subsurface Explorations

Subsurface explorations are performed to provide necessary information on soil characteristics and properties. Timely completion of the subsurface explorations is important for successful project development and design. Failure to deliver geotechnical information may cause project delay and damage project performance. Previous literature has seldom examined schedule performance and delay of subsurface exploration. This study aimed to evaluate the operational performance of subsurface exploration by analyzing empirical data on 77 subsurface exploration projects collected between October 2009 and June 2011. The delay analysis identified the primary effects on operational performance of subsurface exploration, namely, unclear data requirements, scope change, permitting, and unexpected conditions. A forecasting model to predict project duration from variables such as number of borings, boring types, early performance warnings, driller issues, and risk events is proposed, and a series of preliminary recommendations to mitigate delay risk is suggested.