a.
A side elevation should be sketched to show the general features of the bridge,
including the number of spans, piers, abutments, and their types and construction
materials. Critical dimensions (such as span length, height above streambed, water level,
and panel length) should also be noted. A cross section of the stream or gorge may also be
included in the sketch.
b.
The critical span (the span with the least load-carrying capacity) should be
sketched in cross section. The sketch should show enough bridge construction detail to
compute the MLC and to determine maintenance, reinforcement, and demolition needs.
Such items as span width, type, construction material, and structural design should be
included. Tables 2-5 and 2-6 outline the required dimension measurements for each of the
seven basic spans types. Measure these features and record them on the reverse of
DA Form 1249.
Table 2-5. General Dimensions Required on the Seven Basic Bridges
Simple
Dimension Data
Slab
T beam
Truss
Girder
Arch
Suspension
Stringer
Overall length
x
x
x
x
x
x
x
Number of spans
x
x
x
x
x
x
x
Span length
x
x
x
x
x
x
x
Panel length
x
x
Height above streambed
x
x
x
x
x
x
x
Height above estimated normal
x
x
x
x
x
x
x
water level
Traveled-way width
x
x
x
x
x
x
x
Overhead clearance
x
x
Horizontal clearance
x
x
x
x
x
x
x
x = a required dimension
c.
Cross sections of critical members should be sketched on the reverse of
DA Form 1249. Include enough detail to calculate the strength of the individual members.
d.
The site plan sketch should show the location of the bridge; the alignment of the
bridge relative to approaches; the gap or obstacle spanned; the location of unusual features
(such as damage or obstructions); the classification, dimensions, and gradient of
approaches; the direction of stream flow; and enough topographical detail of the barrier to
indicate possible fording sites.
2-5. Bridge Photographs. Up-to-date photographs should accompany the DA Form 1249, if
possible. Ground and aerial photographs are desirable. The minimum photographic
coverage should include a side view, a view from the traveled way of the bridge, and a view
of the underside of the bridge.
EN 5622
2-12
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