Accession Number:

AD0743224

Title:

Research in Long Hole Exploratory Drilling for Rapid Excavation Underground

Descriptive Note:

Final rept. on Phase 1

Corporate Author:

JACOBS ASSOCIATES INC SAN FRANCISCO CA

Personal Author(s):

Report Date:

1972-04-10

Pagination or Media Count:

35.0

Abstract:

Research has led to a new concept generation for drilling a four inch diameter probe hole horizontally. This is to be used to probe ahead of mechanical tunnel boring machines to forewarn of dangers or to allow time for orderly change of tunneling methods or techniques. The method is designed to project the probe hole 1000 feet deep in moderately strong and high strength rock. The equipment was purchased and or designed and manufactured. It was assembled in preparation for field tests in two or more quarries to optimize the design. The first quarry test site was prepared.

Subject Categories:

  • Civil Engineering
  • Machinery and Tools

Distribution Statement:

APPROVED FOR PUBLIC RELEASE