In-Situ Measuring Techniques for Pile Length.

摘要

This report describes an investigation of procedures for determining in-situ the length of foundation or sheet piles. Two techniques were evaluated, one based upon the reflection of sonic energy, and the other upon sensing the electromagnetic flux field that builds up around ferrous objects in the earth's magnetic field. The sonic technique was found to operate satisfactorily within limits on piles made of steel, concrete, and wood, both with the tops exposed and with the tops encased in a concrete decking. The electromagnetic flux-sensing method involves inserting a probe into the soil in the vicinity of the pile. This method appears to be satisfactory for locating tips of ferrous metal piles either in situations where the probe can be jetted into the ground or where it can be inserted into a pre-drilled hole. (Author)