Note: This text has been automatically extracted via Optical Character Recognition (OCR) software.
On The Testing And Strength Of Railway Materials, &C
The strength of bricks necessarily vary much , according to the quality of clay from ivhich they are made in different localities ; but the following tests , made by Mr . Kirkaldy , may serve as guides in specifying brickwork for engineering purposes . Nos . 1 and 2 tables are tests of bricks made by D . W . Barker , of Worcester ; No . 3 table gives results of tests made during the erection of Blackfriars Bridge . In the two folloAving sets of tests , Mr . Kirkaldy bedded the bricks between-pieces
of ivood - £ in . thick , and filled the recesses ivith cement . No . 1 . Stress in pounds when S " 2 p ^ a a 3 £ g « Dimensions in % - | -0 g f-g Descri 8 to
ption . inches ™ ^ « g < and decimals . go n -d ^> 9 > dC o a £ > Jy M S > £ ^ ' u 0 * 0 o o > 2 d , < s B C 3 t-i r * r 4 " Pressed" recessed c-i O O O top and bottom ... 3-20 by 9 T 4 by 4-50 ... 4143 ... 45 , 680 ... , 220 ... 91 , 180 do do do 45590 79775 90320
do . ... . . ... . ... , ... , ... , do . ... do . do . ... do . ... 38 , 760 ... 77 , 830 ... 89 , 640 do . ... do . do . ... do . ... 36 , 180 ... 70 , 960 .... 85 , 820 Average 41-13 ... 41 , 552 .... 78 , 696 ... " 89 , 240 lbs . per square inch 1010 ... 1913 ... 2170 Tons per square foot 65-0 ... . 123-0 ... 139-5
" Builders '" recessed " 0 i - ' ¦ top and bottom ... 3-20 by 9-30 by 4-50 ... 41-85 ... 40 , 960 .. 97 , 240 ... 113 , 220 do . ... do . do . ... do . ... 39 , 280 .. . 95 , 270 ... 106 , 530 do . ... do . do . ... do . ... 36 , 490 ... 87 , 382 ... 101 , 202 do . ... do . do . ... do . ... 33 , 540 ... 81 , 180 ... 95 , 840
Average 41-85 ... 36 , 490 ... 87 , 382 ... , 202 lbs . per square inch 872 ... 2038 ... 2418 Tons per square foot - 56-1 ... 134-2 ... 155-5
No . 3 . Bricks in piers four courses high . Failing Entirely slightly crushed Description of Bricks . Size of pier Mortar . tons per tons per in bricks . ft . supr . ft . supr . Common stock recessed U-by 13 ? ... Lias lime ... 17 . „ 27 " "
Do . do . „ ... „ ... 21 ... 30 Red bricks , machine-made „ ... „ ... 20 ... 40 Do . hand-made „ ... „ ... 20 ... 36 Gault „ Roman Cement ... 24 ... 59 Do 1 by 1 ... „ ... 54 ... 72 Clarks'Sudbury Machine „ ... Portland ... 49 ... 76 Uxbridge red , hand-made „ ... „ ... 44 ... 53 ( To be Continued . )
Note: This text has been automatically extracted via Optical Character Recognition (OCR) software.
On The Testing And Strength Of Railway Materials, &C
The strength of bricks necessarily vary much , according to the quality of clay from ivhich they are made in different localities ; but the following tests , made by Mr . Kirkaldy , may serve as guides in specifying brickwork for engineering purposes . Nos . 1 and 2 tables are tests of bricks made by D . W . Barker , of Worcester ; No . 3 table gives results of tests made during the erection of Blackfriars Bridge . In the two folloAving sets of tests , Mr . Kirkaldy bedded the bricks between-pieces
of ivood - £ in . thick , and filled the recesses ivith cement . No . 1 . Stress in pounds when S " 2 p ^ a a 3 £ g « Dimensions in % - | -0 g f-g Descri 8 to
ption . inches ™ ^ « g < and decimals . go n -d ^> 9 > dC o a £ > Jy M S > £ ^ ' u 0 * 0 o o > 2 d , < s B C 3 t-i r * r 4 " Pressed" recessed c-i O O O top and bottom ... 3-20 by 9 T 4 by 4-50 ... 4143 ... 45 , 680 ... , 220 ... 91 , 180 do do do 45590 79775 90320
do . ... . . ... . ... , ... , ... , do . ... do . do . ... do . ... 38 , 760 ... 77 , 830 ... 89 , 640 do . ... do . do . ... do . ... 36 , 180 ... 70 , 960 .... 85 , 820 Average 41-13 ... 41 , 552 .... 78 , 696 ... " 89 , 240 lbs . per square inch 1010 ... 1913 ... 2170 Tons per square foot 65-0 ... . 123-0 ... 139-5
" Builders '" recessed " 0 i - ' ¦ top and bottom ... 3-20 by 9-30 by 4-50 ... 41-85 ... 40 , 960 .. 97 , 240 ... 113 , 220 do . ... do . do . ... do . ... 39 , 280 .. . 95 , 270 ... 106 , 530 do . ... do . do . ... do . ... 36 , 490 ... 87 , 382 ... 101 , 202 do . ... do . do . ... do . ... 33 , 540 ... 81 , 180 ... 95 , 840
Average 41-85 ... 36 , 490 ... 87 , 382 ... , 202 lbs . per square inch 872 ... 2038 ... 2418 Tons per square foot - 56-1 ... 134-2 ... 155-5
No . 3 . Bricks in piers four courses high . Failing Entirely slightly crushed Description of Bricks . Size of pier Mortar . tons per tons per in bricks . ft . supr . ft . supr . Common stock recessed U-by 13 ? ... Lias lime ... 17 . „ 27 " "
Do . do . „ ... „ ... 21 ... 30 Red bricks , machine-made „ ... „ ... 20 ... 40 Do . hand-made „ ... „ ... 20 ... 36 Gault „ Roman Cement ... 24 ... 59 Do 1 by 1 ... „ ... 54 ... 72 Clarks'Sudbury Machine „ ... Portland ... 49 ... 76 Uxbridge red , hand-made „ ... „ ... 44 ... 53 ( To be Continued . )