Evaluation and prediction of tunnel boring machine performance in variable rock masses

Laughton, C (1998) Evaluation and prediction of tunnel boring machine performance in variable rock masses. PhD thesis, University of Texas at Austin, USA.

Abstract

Each Tunnel Boring Machine (TBM) excavation system is comprised of many subsystems, each with performance and reliability characteristics which may be dependent or independent of the rest of the subsystems. Each rock mass to be tunneled varies in intact rock and rock mass properties, and our knowledge of what lies ahead along a tunnel drive is necessarily imperfect. It is important to be able to describe both equipment and property variability and knowledge uncertainty in order to choose among different excavation systems for a given project, and to establish realistic expectations for excavation completion date and cost. This study summarizes the assembly and application of a TBM-drive data base to estimate TBM mining schedule and cost. The data base contains performance, site, machine and rock mass parameters on over 600 TBM case histories involving the use of full face, single disc cutter equipment. The data was used to develop predictive methodologies that allow for simulation of TBM performance in a geologic framework. The adoption of the data base and predictive methodologies improves the ability of the geologist and engineer to identify and quantify the major impacts of rock mass conditions on TBM performance, aids in the preparation of mitigation measures, and, most importantly, provides a mechanism for quantifying excavation risk within the context of the TBM project plan. The probabilistic predictions of time and cost to complete tunnel generated from these studies can better reflect the intrinsic uncertainties of tunneling work than the "unique number philosophies" currently employed in the civil engineering community. The use of planning methodologies based on probable outcomes allow for project decisions to be based on a realistic prediction that takes account of the high level of uncertainty that is inherent in the planning of most tunnel projects.

Item Type: Thesis (Doctoral)
Thesis advisor: Wright, S G
Uncontrolled Keywords: liability; reliability; uncertainty; equipment; tunnel; civil engineering; excavation; civil engineer; simulation
Index terms: tunnel, liability, face, civil engineer, philosophy, methodology, excavation, mitigation, history, engineer, mining, estimate, variability
Subjects: research methods, financial risk, geotechnical engineering, philosophical studies, infrastructure and transport systems, liability law, statistical analysis, profession, psychology, construction operations, architectural and construction history, financial and cost management
Topics: Cost Management, Research Practice, Engineering Principles, Roles and Professions, Legal Issues, Organizational Design, Site Management
Descriptive scope: 3 PCT

N.B. Descriptive scope is a count of how many of the five facets of empirical research are indicated by the words used in title, abstract and keywords. It is not intended as a judgement on the research; merely a count of the kind of word we would expect to indicate Phenomenon, Concepts, Theoretical framing, Empirical techniques, Analytical techniques. If all five are present, then a code of “5 PCTEA” will indicate this. If you feel the coding for this record is questionable, we welcome discussion around the terms we matched or the way we categorized them. The facet you would expect may not be coded, or a facet may be coded inappropriately. This can also bear on a larger question, of which facets should be treated as defining in construction management research. Please get in touch, and we will look at it. More details here