Systems and cost analysis for a Nuclear Subterrene Tunneling Machine. A preliminary study [report]

J.H. Altseimer
1973 unpublished
Tfas basic system components of large yoeK-selting Nuclear Subterrene Tunneling Machines (SSTMs) have been conceptualized and defined for a preliminary tunneling cost estimate and comparison tilth costs using tunnel-boring machines (TBKs) and other conventional tunneling techniques. Two initial types of HSOfc are considered: Type I. peripheral kerf-melting penetrators plus centrally located rotary cutters for soft ground and rock; and TJrgeJKj kerf-meltins penetrators plus multiple, hot
more » ... ltiple, hot ruck-fracturing penetratore fd very hard rock. Tunneling coste for HSTMs wre very close to those for TBMs, if operating conditions for TBMs are favorable. However, for variable formations and unfavorable conditions such as soft, vet, bouldery ground or very hard rock, the K5TMs are far more effective. Estimates of cost and percentage use of HSTMs to satisfy U.S. transportation tunnel demands Indicate a potential cost savings of 850 million dollars (1969 dollars) through 1990. An estioated BS1M prototype demonstration program cost of $100 million over an eight-year period results 5n a favorable beneflt-to-cost ratio of 6.5. Ihe NSm systems are characterized by large capital costs compared to conventional IBM*. Ksvever, many higher-cost items and components are expected to have long service lives cud will bs used for more then one tunnel project Instead of writing off the tu&neler after each project as in current TBM practice. The ccst of thermal energy for rock melting is not a large percentage of the total project cost.
doi:10.2172/4444905 fatcat:7l5ocmpomrdwjefytvrmhp7vxi