|
Chicago, February 5th, 1914. |
American 3-Way Prism Co.,
3646 South Ashland Avenue, Chicago
Gentlemen:--The following
is a report of our "Transverse Tests" on certain specimens
of your Reinforced Concrete Slab Construction made
with your glass No. 151.
The specimens were 17½" wide
by 54", 78", and 102" long, respectively. In the 17½"
width there were three rows of the No. 151 glass.
The longitudinal reinforcement,
consists of 5/16" twisted square bars, two at each edge,
2" c. to c. and two in the center between the rows of
glass, 4½" c. to c.. The longitudinal reinforcement
was carried 5/16" from the bottom of the slab and the
transverse reinforcements 5/8" from the bottom of the slab.
Conduct of Tests
The specimens were successively
placed on supports 8', 6' and 4' c. to c. The loads were
applied on the 1/3 points of the spans and under increasing
loads the deflections at the center of the spans were
measured. The observed loads and deflections were carefully
plotted.
|
Summary of Tests
Following is a summary of the
deflections under the calculated uniformly distributed
loads.
| Slab No. |
151-3 |
151-2 |
151-1 |
|---|
| Span in Feet |
4' |
6' |
8' |
|---|
| Cal.Distr.Load, Lbs. per Square Foot |
Deflections at Center of Span, Inches |
|---|
| 0 |
.0 |
.0 |
.0 |
| 50 |
.0 |
.05 |
.29 |
| 100 |
.01 |
.28 |
1.67 |
| 150 |
.035 |
.63 |
| 200 |
.06 |
1.01 |
| 250 |
.10 |
1.40 |
| 300 |
.16 |
1.87 |
| 350 |
.22 |
2.62 |
| 400 |
.28 |
| 450 |
.33 |
| 500 |
.40 |
| 550 |
.46 |
| 600 |
.54 |
| 700 |
.67 |
| 800 |
.83 |
| 900 |
1.03 |
| Max.Distr.Load Sustained |
967 |
358 |
139 |
| Deflections under Maximum Load |
1.18 |
2.77 |
2.97 |
|
(Signed) ROBERT W. HUNT & CO. |
|
