June 12, 1914.

THE COLLIERY GUARDIAN.

1303

The Use of Ferro-Concrete in Mining.

The present century has witnessed an astonishing
increase in the employment of armoured concrete for all
descriptions of building construction, the rapidity with
which it can be applied and its adaptability to form
being two of the main advantages that have prompted
its use.

The mine has always appeared to provide exceptional
opportunity for the employment of such forms of con-
struction, not only on the surface, but below ground
also, in shaft, roadways, and insets. In America and
Germany the application of ferro-concrete in mines has
probably been greater than in this country, although
British mining engineers are now fully alive to its
possibilities.

Fig. 3.—Ikon Ring Frames.

I

. . .1
-

■ ■

One of the pioneers in the use of such material in
Germany was the firm of Franz Schluter, of Dortmund,
who have carried out a number of interesting works in
the large Westphalian collieries, some of which are
illustrated below. The fact that the works of the firm
are situated in the heart of the Ruhr coalfield led them

at an early date to endeavour to remove or modify the
nuisance caused by the noisy coal shoots in operation
at the collieries. The desired end was attained by
substituting ferro-concrete for the sheet iron formerly
used, by which the noise was greatly reduced, and at
the same time considerable advantages were derived
from the smooth surface, and the employment of round
or oval instead of rectangular cross sections. Ferro-

concrete was next used in the construction of fan drifts,
for which purpose it held out many advantages,
amongst them being the greater strength combined with
reduced thickness of wall, the safety from fire, the
smoothness of surface, and the insensibility to the
disintegrating effects of acid mine water and shocks.

It was some time, however, before ferro-concrete
obtained its proper vogue in mine construction, for the

\295.

09

20}

5 09

-

o Bored tubbings • Forced off screws | Screws



Figs. 1 and 2.—Showing the Effect of Earth
Pressures upon Tubbing Segments.

Fig. 4.—Pit-eye in Alma No. 5 Pit, Gelsenkirchen.

J

Distance between walls 6 m. Pit-eye 8 m. wide.



Fig. 5.—Shaft and Pit-eye.

Fig. 6.—Pit-eye.

Sr'

’“■A.-

‘ ¥

i “ i.

Fig. 7.—Pit-eye.



Fig. 8.—Cross-cut at Aima No. 5£Pit, Gelsenkirchen.