The split-tube multiple-point borehole extensometor

摘要

The split-tube multiple-point borehore extensometor is a new type of measuring instruments for the internal displacement of rock mass. Its advantage is simple, cheap and easy for installation. The reuslts of calcualtion and experiment show that when a split-tube anchor with 120mm length is thrusted into a borehore, the anchorage force is within 1.539kN approx 4.606 kN and meets extensometor's working demands.