New pneumatic drilling machine for strengthening

foundations

The Use of pneumatic drilling machines for installing underground mains without

the digging of trenches is held up by the lack of precision with which the machine can be

made to exit at the desired point and the impossibility of correcting its motion in the

ground.

Various Organizations in this country and foreign companies have attempted to

improve the accuracy of the tunnel excavation by using different types of extenders

attached to the body of the machine.

This project is a design of a new pneumatic drilling machine with a sectional

expander and gives its mechanical characteristics. The technology of the deep

compaction of soil in the vertical plane is examined.

Relations and nomograms are presented to determine the distance between drill

holes and drilling speed in relation to the diameter and depth of the holes and the

sequence in which they are expanded. The dependence of the duration of soil compaction

on the time spent performing the main and auxiliary operations is also determined and the

design is made in this project.