ACI Concrete Strength Testing Technician,
April 8-9
Save
Terms in this set (175)
C39/M: Cylinder Place the specimen on the lower bearing
Testing block, and align under the center of thrust of
the upper bearing block.
After all surfaces are
wiped down, what is
next?
C39/M: Cylinder Wipe clean the surfaces of the platens,
Testing spacer disks, and bearing surfaces of the
specimen.
After the lower
bearing block is
positioned, what is
the next step?
C39/M: Cylinder The time of casting, unless otherwise
Testing specified.
From when is the age - 1 days: +/- 0.5 hours
of a specimen - 3 days: +/- 2 hours
measured? What are - 7 days: +/- 6 hours
the tolerances for - 28 days: +/- 20 hours
specimens of 1, 3, 7, - 90 days: +/- 48 hours
, Check the alignment of the specimen at two
C39/M: Cylinder locations 90° apart, making sure alignment is
Testing with respect to the direction of load
application is within:
The initial load has
been applied in a - 0.5°
test with unbonded - 1/8in per 12in (3mm per 300mm)
caps. What is to be - 1/12in per 8in (2mm per 200mm)
done next?
If off, reload and check again.
C39/M: Cylinder Apply an initial load of less than 10% of the
Testing anticipated load and pause the machine.
The machine has
been zeroed. If using
unbound caps, what
is the next step?
Continuously and without shock.
C39/M: Cylinder
35 +/- 7 psi/second (0.25 +/- 0.05 MPa/sec)
Testing
For the first half of anticipated loading,
The machine has
machine may be advanced at a higher rate.
been zeroed, the
This is not mandatory.
initial load has been
applied, and any
The specified loading rate shall be
necessary alignment
maintained for at least the second half of the
checks have been
loading phase.
made. How should
they load be
Once yielding had begun, indicated by a
applied?
drop in the loading rate, no further
adjustments are allowed.
C39/M: Cylinder Zero the machine.
, Place the lower bearing block on the
C39/M: Cylinder
machine or platen with the hardened face
Testing
up.
What is the first step
The lower bearing block may be the platen
of the procedure?
in the machine.
C78/M: Flexural ... maintain moisture on the specimen.
Testing
After removing the
specimen from moist
storage, care must
be taken to...
KEEP SPECIMEN MOIST.
Use the 0.015in (0.40mm) felt gauge to check
all four contact points. If it passes through,
C78/M: Flexural the entire length of the specimen must be
Testing ground or capped.
After the initial load Use the 0.004in (0.10mm) feet gauge to
has been applied, check all four contact points. If it passes
what two checks through any location, the specimen must be
must be performed? shimmed at all four locations.
Shims are leather, 1/4in (6mm) thick, 1-2in
(25-50mm) wide, and cover the width of the
specimen.
Measure the overall length of the specimen.
C78/M: Flexural
Testing
Verify that the span is at least three times the
depth of the specimen.
After the specimen
has been removed
, C78/M: Flexural R (Modulus of Rupture) to 5psi (0.05MPa)
Testing b (average breath) to 0.05in (1mm)
d (average depth) to 0.05in (1mm)
Testing and L (span length, 3x depth) to 1in (1mm)
calculations are P (total load) to 1lbf (1N)
complete. what
needs to be Curing history, any capping or grinding
reported, and to performed, defects, age, specimen ID
what accuracy?
C78/M Flexural R= Px3xa÷ b÷d ÷d
Testing
P = total load
The average breath a = average distance from support to line of
and depth have been fracture
taken and the b = average breath
fracture occurred in d = average depth
the 5% zone. What
formula should be
used for the modulus
of rupture?
C78/M: Flexural R= PxL÷ b÷d ÷d
Testing
P = total load
The average depth L = span length = 3 x depth of specimen
and breath have b = average breath
been taken and the d = average depth
fracture occurred in
the middle third.
What formula should
be used for the
modulus of rupture?
C78/M: Flexural Position the beam in the testing apparatus
Testing with the finished surface placed to one side.
April 8-9
Save
Terms in this set (175)
C39/M: Cylinder Place the specimen on the lower bearing
Testing block, and align under the center of thrust of
the upper bearing block.
After all surfaces are
wiped down, what is
next?
C39/M: Cylinder Wipe clean the surfaces of the platens,
Testing spacer disks, and bearing surfaces of the
specimen.
After the lower
bearing block is
positioned, what is
the next step?
C39/M: Cylinder The time of casting, unless otherwise
Testing specified.
From when is the age - 1 days: +/- 0.5 hours
of a specimen - 3 days: +/- 2 hours
measured? What are - 7 days: +/- 6 hours
the tolerances for - 28 days: +/- 20 hours
specimens of 1, 3, 7, - 90 days: +/- 48 hours
, Check the alignment of the specimen at two
C39/M: Cylinder locations 90° apart, making sure alignment is
Testing with respect to the direction of load
application is within:
The initial load has
been applied in a - 0.5°
test with unbonded - 1/8in per 12in (3mm per 300mm)
caps. What is to be - 1/12in per 8in (2mm per 200mm)
done next?
If off, reload and check again.
C39/M: Cylinder Apply an initial load of less than 10% of the
Testing anticipated load and pause the machine.
The machine has
been zeroed. If using
unbound caps, what
is the next step?
Continuously and without shock.
C39/M: Cylinder
35 +/- 7 psi/second (0.25 +/- 0.05 MPa/sec)
Testing
For the first half of anticipated loading,
The machine has
machine may be advanced at a higher rate.
been zeroed, the
This is not mandatory.
initial load has been
applied, and any
The specified loading rate shall be
necessary alignment
maintained for at least the second half of the
checks have been
loading phase.
made. How should
they load be
Once yielding had begun, indicated by a
applied?
drop in the loading rate, no further
adjustments are allowed.
C39/M: Cylinder Zero the machine.
, Place the lower bearing block on the
C39/M: Cylinder
machine or platen with the hardened face
Testing
up.
What is the first step
The lower bearing block may be the platen
of the procedure?
in the machine.
C78/M: Flexural ... maintain moisture on the specimen.
Testing
After removing the
specimen from moist
storage, care must
be taken to...
KEEP SPECIMEN MOIST.
Use the 0.015in (0.40mm) felt gauge to check
all four contact points. If it passes through,
C78/M: Flexural the entire length of the specimen must be
Testing ground or capped.
After the initial load Use the 0.004in (0.10mm) feet gauge to
has been applied, check all four contact points. If it passes
what two checks through any location, the specimen must be
must be performed? shimmed at all four locations.
Shims are leather, 1/4in (6mm) thick, 1-2in
(25-50mm) wide, and cover the width of the
specimen.
Measure the overall length of the specimen.
C78/M: Flexural
Testing
Verify that the span is at least three times the
depth of the specimen.
After the specimen
has been removed
, C78/M: Flexural R (Modulus of Rupture) to 5psi (0.05MPa)
Testing b (average breath) to 0.05in (1mm)
d (average depth) to 0.05in (1mm)
Testing and L (span length, 3x depth) to 1in (1mm)
calculations are P (total load) to 1lbf (1N)
complete. what
needs to be Curing history, any capping or grinding
reported, and to performed, defects, age, specimen ID
what accuracy?
C78/M Flexural R= Px3xa÷ b÷d ÷d
Testing
P = total load
The average breath a = average distance from support to line of
and depth have been fracture
taken and the b = average breath
fracture occurred in d = average depth
the 5% zone. What
formula should be
used for the modulus
of rupture?
C78/M: Flexural R= PxL÷ b÷d ÷d
Testing
P = total load
The average depth L = span length = 3 x depth of specimen
and breath have b = average breath
been taken and the d = average depth
fracture occurred in
the middle third.
What formula should
be used for the
modulus of rupture?
C78/M: Flexural Position the beam in the testing apparatus
Testing with the finished surface placed to one side.
