Product description— h-3033a – Humboldt H-3033A Concrete Beam Tester User Manual
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Product Description— H-3033A
The Humboldt Manufacturing Co Model H-3033, Concrete Beam Tester, is
a lightweight portable unit to easily determine the flexural strength of up to
6x6x30" test beams. Hydraulically driven, it uses the third-point loading method
defined in ASTM C78 and AASHO T97 with continuous dial gauge readings.
Physical Specifications:
Function
Modulus of rupture of concrete beams using
third point loading
Range
0 - 1,250 lbf/in
2
(for 6x6”)
0 - 15,000 lbf
Shipping weight:
lb
Overall height:
"
Base dimension:
"
Theory Of Operation
The modulus of rupture
1
is defined as:
(1)
where:
R = modulus of rupture in lbf/in
2
b = average specimen width in inches
P = maximum applied load in lbf
d = average specimen depth in inches
L = span length in inches
1
R is actually the stress in lbf/in
2
of the outer fibers of the beam (in compression at the top,
in tension at the bottom).
Where: S = stress at top or bottom of the beam in lbf/in
2
M = bending moment (P/2 x L/2 – P/2xL/6)
c = distance from centroid to top of beam (d/2)
I = Inertia about the centroid (bd
3
/12)