ASSESSMENT OF RESIDUAL LIFE OF GIRDERS OF BRIDGE No

3. CONDITION OF STEEL GIRDERS OF BR.NO. 73 &75 (OLD)
3.1 The bridge No. 73 & 75 ( abandoned ) are located on Vasai Creek
between Bhainder and Naigaon stations of CCG – VR suburban
section. The old is located on the west most side of the existing bridge.
There are 69 x 2 = 138 nos. of 18.3 m span girders on bridge No. 73 and
25 x 2 = 50 nos. of 18.3 m span girders in bridge No. 75. Thus, there are
188 nos. girders of 18.3 m effective span. There 8 nos. of 6.1 m span
girder in bridge No. 73 & 75 which can not be reused since these have
already completed their fatigue life.
3.2 The details of girders are as follows:
a) Effective Span - 18.3 m
b) Overall length - 18.95 m
c) Height at end - 1.87 m
d) Height at center - 1.91 m
e) Flange width - 430 mm
f) C/C of girder leaves - 1.88 m
g) Loading Standard - BG standard of 1916
h) Drawing No. - CEN/57728/11-D
i) Manufactured by - M/s P& W Maglellan Ltd., BB & CI. Co. -
1923, Clutha Works Glasgow.
3.3 The girders of the bridge were inspected visually by Dy. CE (Br.) BL and
the following points were brought out:
The girders in the bridge can be classified into two broad categories
based on visual inspections:
a) Type I : The type I girders are having:
i) Corrosion in top flange plates upto 7 mm at sleeper seat locations i.e.
at every 65 cms spacing.
ii) 80 % gussets are having corrosion by minimum 4 mm, out of total 8
mm thickness. Many gussets are perforated.
iii) 30-35 % rivets have lost more than 50 % head due to corrosion in top
flange.
iv) Bracings are generally in satisfactory condition, except the end cross
frame top lateral angles, which are corroded and reduced in thickness.
v) There is slight corrosion in the bottom angle of main girder and the
same is generally OK.
vi) There is corrosion of upto 1 mm at the junction of the web plate with
bottom main angle.
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