Book-bot.com - Transactions of the American Society of Civil Engineers, vol. LXVIII, Sept. 1910 - The New York Tunnel Extension of the Pennsylvania Railroad. - The East River Tunnels. Paper No. 1159 by Woodard, S. H.;Mason, Francis;Brace, James H.

Transactions of the American Society of Civil Engineers, vol. LXVIII, Sept. 1910 - The New York Tunnel Extension of the Pennsylvania Railroad. - The East River Tunnels. Paper No. 1159 by S. H. Woodard;Francis Mason;James H. Brace
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| | | | | |
Earth |Poling and |106+34 | 99+11 |Jan. 13, '07|Apr. 17, '07|
| breasting | | | | |
| | | | | |
Mixed |Rock cut | 99+11 | 93+96 |Apr. 17, '07|Oct. 24, '07|
| | | | | |
Rock |Bottom heading | 93+96 | 93+58 |Oct. 24, '07|Nov. 14, '07|
| | | | | |
Rock |Center heading | 93+58 | 92+42 |Nov. 14, '07|Dec. 27, '07|
| | | | | |
Rock |Bottom heading | 92+42 | 91+05 |Dec. 27, '07|Feb. 24, '08|
| | | | | |
Mixed |Rock cut | 91+05 | 90+57 |Feb. 24, '08|Mar. 20, '08|
--------------+-----------------+---------+---------+------------+------------+

--------------+------+--------+--------+--------------------------------------+
| | |Rate of | |
|Number| |progress| |
| of | Linear |in feet | |
Material. | days.| feet. |per day.| Remarks |
--------------+------+--------+--------+--------------------------------------+
{| 14} | | {|Excavation in normal air, and before |
Rock {| 15}57| 69 | 1.21 {|advance of shield. |
{| 28} | | {| |
{| | | {| |
| | | | |
Rock {| 26}55| 53 | 0.96 {|Bottom heading timbered to avoid the |
{| 29} | | {|possibility of a break. |
| | | | |
Mixed | 25 | 22 | 0.88 |Bottom heading timbered. |