G. Chemolli: Die Verbreitung von Gewölbebauten aus Beton und Stahlbeton für Brücken und Decken in der österreichisch-ungarischen Monarchie
Beton- und Stahlbetonbau 112 (2017), Heft 12 829
rials, constructions methods and costs. It also mentioned
the possibility of using, for vaults spanning more than
40 m, blocks of artificial stones, like Stampfbeton, made
with concrete mix based on Portland cement in proportion
1:6, eventually reinforced with iron bars [37, p. 93].
Engineer Julius Chailly, member of the Cement-Comité
and entrepreneur with concrete in Vienna since 1871,
had presented a similar idea during an assembly of the
Verein in February 1891 ; at that time, Chailly was
patenting a system to build vaults for bridges and floors
with hollow artificial stones .
In June 1892, the Gewölbe-Ausschuss underscored the
importance to organise other tests, with complete load
instead of one-sided load, on vaults built respectively with
normal bricks, Schlimp’s clinkers (Kunstbasaltsteinen),
eventually stone ashlars. These trials would complete information
collected during the tests in Purkersdorf, with
data on collapse under compression. For practical reasons,
the vaults should have spans between 10 and 12 m,
5 Tests in Purkersdorf, 1891–1892
After the tests on vaults spanning 10 m, and the construction
of vaults in the Monier system spanning until
20.25 m, loading tests on arches in concrete and reinforced
concrete with 23 m span took place.
The vaults spanning 23 m were tested in a quarry in Purkersdorf,
with one-sided uniformly distributed load, consisting
of railway rails. A rabble stone and a brick masonry
arch, with joints in cement mortar, were built and
proofed in 1891; they were 1.10 m thick at the springing
and 0.60 at the keystone, and collapsed respectively for
6.44 t and 5.87 t “per Meter Gewölbe” . The ashlar
stone arch was not built. A Stampfbeton, a Monier and
an iron arch were constructed and tested the following
year [37, pp. 14–17] (Fig. 14).
Against the Gewölbe-Ausschuss’s opinion, Pittel &
Brausewetter decided to build the vault, 0.70 m thick, using
three different concrete mixes (proportions 1:2 and
1:5 where tensile stresses were expected, 1:8 for the rest)
based on Portland cement from Herget manufacture in
Radotin (Prague). Arch and abutments were separated by
asphalt sheets. The vault was built on April the 23rd, loading
tests were conducted on the 18th and 19th of July; the
structure collapsed under 7.24t “per laufenden Meter Gewölbe”.
The Monier arch was built on June 2nd, it was
0.60 m thick at the springing and 0.35 m in keystone. It
was reinforced with iron near the intrados and near the
extrados. It was loaded on 25th and 26th of August and
collapsed for 12.70 t “per laufenden Meter Gewölbe”.
During the tests in Purkersdorf, the entity of the loads
was varied in time, the cracks and the movements of the
points of the axis of the arch were accurately observed
and measured (Fig. 15). The concrete mix design and all
the construction operations were carefully studied; samples
of each mix were sent to the Testing institute for hydraulic
binder of the city of Vienna. The data collected
during the experiments with the brick, stone and Stampfbeton
arches were studied by Josef Melan (1853–1941),
professor at the Technische Hochschule in Brünn [37,
pp. 44–69]. A theoretical elaboration of trials with the
Monier arch was published in 1896 by Josef Anton
Spitzer (1856–1922), engineer in the company G. A.
Wayss & Co. . The studies on the trials of the Gewölbe
Ausschuss were characterized by the use of elastic
theory for calculation of vaults.
The tests showed the higher load carrying capacity of
concrete, reinforced or not, in comparison to brick or
stone. They also diffused information on construction
operations and on quality of materials. Nevertheless, they
could not answer the question of the durability of those
structures, which in the following years remained a possible
obstacle to their affirmation.
In its final report, published in 1895, the Gewölbe-Ausschuss
included some general indications about mateFig.
14 Loading tests in Purkersdorf, 1892. Vault in the Monier system (right)
Belastungsversuche in Purkersdorf, 1892. Gewölbe im Monier-System
Fig. 15 Loading tests in Purkersdorf, 1892. Measurements 
Belastungstests in Purkersdorf, 1892. Messungen