30 molesworth’s pocket-book
Strength of various Materials. (Barlow.)
Ultimate Strength. Working Strain.
Tons per sq. inch. Tons per sq. inch.
Material. f tc S ci Compres- sion. bi) G
.2 * p. ? cC 0> 02 •S E-t §
1 Steel bars .. .. 45 70 30 9 9 5
Steel plates .. .. 40 — — 8 —‘
I Wrought-iron bars plates 25 22* 17 17 20 20 5 3+ 4
Iron wire cables .. 40 — —— 8
Cast iron .. .. 7+ 48 14 If 9 3
Ash »i 4 4 It 1 i
Beech 5 4 —— 1 i —
Elm 6 41 t 1 i
Fir 5 24 i J i A
Oak 61 3J 1 1 i H
Teak 5 — 1 1
Granite —— —— t
Sandstone •. •. —— It — ——
Brick in cement .. 1 i to A 50 lbs. 180 IDS
Lloyd’s Kules for Iron used in the Construction of
Ikon Masts, Yards, &c.
The iron should be of a good malleable quality, and quite
free from surface or other defects
The iron should stand a tensile strain of 20 tons to
inch, and should be capable of standing the followii
tests whpn cold without fracture, through the angles under-
tbe square
ig bending
mentioned.
Thickness of plate A
With the grain .. 25° 30°
Across the grain 8° 11°
37°
13°
; 55° \ 65° 70°
15° 1 17° 20° 25°
The plates to be bent over a slab, the corner of which should
be rounded with i inch radius.