160 ANNUAL REPORT 
was used in the work. To strengthen the work, 14% inch wire mesh was 
placed about 2 feet apart horizontally and vertically in the concrete, the 
wire being 4% inch in diameter. The cost of the work was: 
For 680 cubic yards of concrete at $9.30 per cubic yard...... $6,324 00 
Macadam appurtenancest Ctce aanmcc nie ciel increras Gren eee or 2,338 00 
Total Costcote DrIdSZes tee eee $8,662 00 
Fall Creek Bridges, Indianapolis—The Melan arch was among 
the pioneers in steel concrete bridge construction. In the Melan con- 
struction steel I-beams are imbedded in the concrete, the base of the 
I-beam being from 3 to 5 inches from the intrados of the arch. 
_ ENG. News. 
Fig. 97.—A Melan Concrete Bridge, Indianapolis, Ind. 
The following description of the bridges built in 1900, over Fall 
Creek, Indianapolis, where Illinois and Meriden streets cross that creek, 
will illustrate the Melan system applied to bridges. The city had been 
burdened for years with the great expense of maintenance and repairs 
upon the many steel bridges within the corporate limits, until at last 
the authorities decided to replace the bridges at these points with per- 
manent structures. Bids were invited upon three forms of bridges— 
steel girders, steel concrete and, stone bridges. The bids upon steel 
bridges were the lowest, but were rejected because steel girder bridges 
lack both in beauty and durability. The lowest bid upon concrete was 
$105,340.00, while the lowest bid upon stone was $140,996.00, although 
close at hand there was an abundance of good building stone. One of 
the completed bridges, also one with the steel skeleton in place ready 
to receive concrete, is shown in figures 97 and 08. 
The proportions of the concrete used in the back walls, spandrels 
and piers were, I part cement, 3 parts sand and 6 parts gravel. For the 
arches, I part cement, 2 sand and 4 parts gravel were used. The gravel 
and sand were taken directly from the bed of the stream. 
