Ársrit Verkfræðingafjelags Íslands - 01.01.1914, Blaðsíða 34

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of the minimum thicknesses. Breymann is of the
opinion, that average walls should be 3 cm thicker
than this and strong walls should be still 3 cm
thicker. The rules are adapted to limed brickwalls.
By means of these rules, it is an easy malter to make
convenient precepts as to the thickness of the walls
of concrete houses, the proportions could be about
the same, for according to our usual working me-
thods we can not expect, that concrete of 1 : 4 : 8 has
a greater bearing-strength, than an ordinary brick-
wall. Regarding the internal walls similar provisions
could be made. The increase of the thickness ofwalls,
which are not sustaining, could of course be a dilferent
and a smaller one. Only I should tliink it unadvis-
able to allow to make any outer wall thinner than
23 cm — supposing it was not an absolutely water-
proof one, and walls of that thinness are not warm
enough for dwellingrooms. Therefore it seems to me,
that when the question is of outer walls, thinner
than 32 cm (12"), a prolective lining should be de-
manded. At last, some bounds should be set to the
length of concreted walls, going belween cross walls
made from the same material. As a rule their length
should not exceed 10 m.
In a similar way rules could be made with re-
gard to the use of reinforced concrete for walls,
stairs, floors and ceilings. I suppose that, in future,
concrete lloors will be more commonly used, the price
of timber being so enormous, that concrete floors
hardly will prove more expensive, (at least not in
houses where tlie interval belween the supporting
walls is large, so the girders must be high) even if
the layer of concrete was floored with wooden boards
laid on joists, the void being filled with potters clay
or the like. On the olher hand, wooden girders do
not fit in very well wilh concreted walls, at least
their ends should not be wrapped up in any way,
only carbolinated.
I do not think there would be any danger of
straining although the ends of the girders were co-
vered with concrete, in the course of time the wood
will shrink sufficiently as to preclude tliat possibility.
I do not wish to enter into a greater length re-
garding the provisions of the build. reg. as to build-
ing from concrete. As regards carpentry the building
regulations need nol be much allered. Still I think,
that the space between the floor-girders should be
adjusted to the thiekness of the flooring-boards.
But before leaving this subject, I wish lo empha-
size, that as far as possible the building regulations
should be made to contribute to a more careful build-
ing and withstand hasty and careless working. Al-
though these measures apparently should result in
increased expenses, thal would only be at the very
beginning, in the long run they would pay. There-
fore people who build would not have any reason to
be discontented on account of the expenses imposed.
Owing to the rough climate of our country, the
need of preservation is greater here, than almost
everywhere in our neighbourcountries. Therefore I
think it very advisible, that the building regulations
should authorize the building commiltee to claim,
that every work, belonging to ils sphere of act-
ion, should be managed by a man whose ability
was recognised by the commiltee. In support of my
argument I will mention, that provisions tending
towards this are to be found both in the building
regulations of Christiania (from 1899) and in the
»Betankande med förslag till byggnadsstadga för
rikel«, before menlioned.
3. Einige Mitteilungen iiber isliindisches „Mel“-Korn und Algern.
(Auszug aus einem im Ingenieur-Verein Islands von Herrn Ingenieur-Cliemiker Ásgeir Torfason
am 30. Jan. 1913 gehaltenen Vortrag).
Island ist so zu sagen ein brotloses Land. Keine
der ublichen Getreide-arten wachsen hier unbebaut
und werden nur im ganz geringen Masse bebaut.
Allerdings erzahlt man zu alten Zeiten vom Kornbau
(Gerste) und darf wohl annehnen, dass das Korn viel-
leicht in guten Jahren reif geworden ist. Wie viel
der Kornbau auch zu diesen Zeiten gewesen sein mag,
ist derselbe jedoch iin Lauf der Jahre aufgegeben
und vergessen worden; ist auch wahrscheinlich nie-
mals lohnend gewesen. In den letzten Jahren sind
einige Versuche wieder gemacht worden, die trotz eini-
germassen guten Gelingens gezeigt haben, dass der
Kornbau liier im Lande weniger lohnend als der
Wiesenbau (Tunbau) ist.
Trolzdem wir aber nicht die iiblichen Getreidear-
ten haben, so haben wir doch hier eine Pllanze, die
Brotkorn liefert, namlich der »Melur« (glymus are-
narius). Allerdings wáchst der Melur lange nicht
úberall auf Island, er gedeiht nur dort gut, wo Sand-
wehen ist.
Wo aber die Bodenverháltnisse fúr ihn gúnstig
sind, wird er gross und kann jedes Jahr reifes Korn
tragen.
Die weiteste Verbreitung hat der Melur in dem
Distrikt Vestur-Skaftafellssýsla gefunden, wo er sogar
als Nahrungsmiltel fúr Menschen benutzt worden ist. In
frúheren Jahrhunderten, als der Handel nur schwierig
und schlecht war, hatle der Melur eine grosse Bedeu-