As
expected, the graph shows a nearly linear decrease in the load bearing
capacity for |
each of
the models with increasing span. The Warren IT model consistently
supported the |
greatest
load for a given span. The Warren RT model carried the least.
This is explained |
largely
by the fact that the Warren IT model had the highest H/S ratio and the
Warren RT |
the
lowest for the spans tested. This is shown in the following images
of the shortest spans |
tested
for each of these two structures. |
. |
 |
 |
|
Fig. 175 - H/S ratios for |
Warren IT and RT |
truss models |
|
|
Warren IT - H/S = .66 |
Warren RT - H/S = .25 |
|
|
. |
The
relationship of the maximum load to the H/S ratio of these models is made
evident by |
the next
graph which compares them directly. |
. |
 |
Fig.
176 - Graph of maximum load vs. H/S ratio for Howe, Pratt, and Warren truss
models |
. |
The
increase in in load bearing capacity with an increase in the H/S ratio is
evident from |
the
graph. Note also that as their H/S ratios decrease the relative
differences in their load |
capacities diminish. The H/S ratios of the models decrease because
their spans increase |
. |
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to Knowhere |
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109 - Building stability - Comparing truss bridge models |
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