Kinzua Viaduct
I could build a scale model of the Kinzua Viaduct , the original, the rebuilt, or the restored. Or all three. A 1/72 scale model would be 4.18 feet tall and 28.50 feet long, which would suit an exibition with four-foot high layouts and a few tons of fake trees.
Another Christopher Greaves Kinzua Viaduct.xls is to reduce the number of struts:-
Struts |
19 |
Length |
27.08 |
324.90 |
inches |
|---|---|---|---|---|---|
Struts |
18 |
Width |
25.65 |
307.80 |
inches |
Struts |
17 |
Struts |
24.23 |
290.70 |
inches |
Struts |
16 |
Struts |
22.80 |
273.60 |
inches |
Struts |
15 |
Struts |
21.38 |
256.50 |
inches |
Struts |
14 |
Struts |
19.95 |
239.40 |
inches |
Struts |
13 |
Struts |
18.53 |
222.30 |
inches |
Struts |
12 |
Struts |
17.10 |
205.20 |
inches |
Struts |
11 |
Struts |
15.68 |
188.10 |
inches |
Struts |
10 |
Struts |
14.25 |
171.00 |
inches |
Struts |
9 |
Struts |
12.83 |
153.90 |
inches |
Struts |
8 |
Struts |
11.40 |
136.80 |
inches |
Struts |
7 |
Struts |
9.98 |
119.70 |
inches |
Struts |
6 |
Struts |
8.55 |
102.60 |
inches |
Struts |
5 |
Struts |
7.13 |
85.50 |
inches |
Struts |
4 |
Struts |
5.70 |
68.40 |
inches |
Struts |
3 |
Struts |
4.28 |
51.30 |
inches |
Struts |
2 |
Struts |
2.85 |
34.20 |
inches |
Struts |
1 |
Struts |
1.43 |
17.10 |
inches |
Struts |
0 |
Struts |
- |
- |
inches |
If the struts are built in series starting from the shorter, outside struts, then we can stop when we have reached the appropriate bridge-length for our model.
A further option is to build it to half, or a quarter, of 1/72 scale so that the overall dimensions are reduced to 25.08 or 12.54 height on the model and 171.00 or 85.50 inches length on the model. The width or trackbed should remain at 1/72 scale 1.67 inches wide. Still we have a bridge more than seven feet long.
(later: I am not sure where I got the width as ten feet; from all the phots it looks more like twenty feet to me)
Scaling Down
https://www.asce.org/project/kinzua-railway-viaduct/
- Twenty iron towers supported the roadbed.
- Six of the towers were higher than those of the Brooklyn Bridge.
- Each tower was composed of four wrought-iron columns.
- The bridge required 110 masonry piers.
- The bridge was 10 feet wide along the top, but the tallest of the towers spreads to 103 feet at the base, giving the structure considerable stability.
“The workforce consisted of less than 100 men, yet they finished construction in just 94 days”. Scaled 1/72 that would be :-
1882 |
100 |
men |
|---|---|---|
94 |
days |
|
10 |
Hrs/day |
|
94,000 |
man-hours |
|
1,306 |
scale man-hours |
|
163 |
scale days |
“The $275,000 viaduct required a record-breaking 3.5 million pounds of iron.”
Scaled 1/72 that would be:-
$275,000 |
Cost |
|---|---|
3,500,000 |
pounds steel |
$3,819 |
scale cost |
48,611 |
scale lbs steel |
https://www.summitpost.org/kinzua-bridge/462209
“The bridge stood on top of 20 towers that supported the rail tracks.”
“The cost of this endeavor was $275,000, or $6,251,000 with inflation adjusted for 2017.”
Avoid modelling thousands of trees by covering them with snow!
The Strut
Struts were four-legged towers composed of two “A-frame” planes linked by diagonal braces.
Struts are latticed (laced) girders, but at our distance/scale they would appear as solid sheet girders.
At 1/288 scale I would require 1,000 inches of strut, four verticals per strut, comes to about 330 feet of ?balsa? wood.
Base piers appear to be ten feet tall, about half-an-inch at 1/288 scale.
The third structure (2004) shows simpler struts. Steel tube rather than steel girder? The viaduct is no longer suitable for rail service, only touring pedestrians.