ASTM C1197-92(1997)
(Test Method)Standard Test Method for In Situ Measurement of Masonry Deformability Properties Using the Flatjack Method
Standard Test Method for In Situ Measurement of Masonry Deformability Properties Using the Flatjack Method
SCOPE
1.1 This test method describes an in situ method for determining the deformation properties of existing unreinforced solid-unit masonry. This test method concerns the measurement of in-situ masonry deformability properties in existing masonry by use of thin, bladder-like flatjack devices that are installed in saw cut mortar joints in the masonry wall. This test method provides a relatively non-destructive means of determining masonry properties.
1.2 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.
1.3 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
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Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn. Contact
ASTM International (www.astm.org) for the latest information.
Designation: C 1197 – 92 (Reapproved 1997)
AMERICAN SOCIETY FOR TESTING AND MATERIALS
100 Barr Harbor Dr., West Conshohocken, PA 19428
Reprinted from the Annual Book of ASTM Standards. Copyright ASTM
Standard Test Method for
In Situ Measurement of Masonry Deformability Properties
Using the Flatjack Method
This standard is issued under the fixed designation C 1197; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This test method describes an in situ method for
determining the deformation properties of existing unrein-
forced solid-unit masonry. This test method concerns the
measurement of in-situ masonry deformability properties in
existing masonry by use of thin, bladder-like flatjack devices
that are installed in saw cut mortar joints in the masonry wall.
This test method provides a relatively non-destructive means of
FIG. 1 Deformation Properties Using Two Flatjacks
determining masonry properties.
1.2 The values stated in inch-pound units are to be regarded
collar joint behind the wythe tested and adjacent masonry are
as the standard. The values given in parentheses are for
neglected. In the case of multi-wythe masonry, deformability is
information only.
estimated only in the wythe in which the flatjack is inserted.
1.3 This standard does not purport to address all of the
Deformability of other wythes may be different.
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
5. Apparatus
priate safety and health practices and determine the applica-
5.1 Flatjack:
bility of regulatory limitations prior to use.
5.1.1 A flatjack is a thin envelope-like bladder with inlet and
outlet ports which may be pressurized with hydraulic oil.
2. Referenced Documents
Flatjacks may be of any shape in plan, and are designed to be
2.1 ASTM Standards:
compatible with the masonry being tested. For determining
E 74 Practice for Calibration of Force Measuring Instru-
load-deformation properties of masonry, flatjacks are typically
ments for Verifying the Load Indication of Testing Ma-
rectangular or semi-rectangular as shown in Fig. 2.
chines
5.1.2 For determination of masonry deformability proper-
ties, dimension A (see Fig. 2) should be equal to or greater than
3. Summary of Test Method
the length of two masonry units. Dimension B should be equal
3.1 Two flatjacks inserted into parallel slots, one above the
to or greater than the thickness of one wythe and not less than
other, in a solid-unit masonry wall are pressurized thus
three in. (76 mm). The radius, R, for circular and semi-
inducing compressive stress on the masonry between them.
rectangular flatjacks shall be equal to the radius of the circular
The installation is shown in Fig. 1. By gradually increasing the
saw blade used to cut the slot.
flatjack pressure and measuring the deformation of the ma-
5.1.3 Flatjacks shall be made of metal or other material such
sonry between the flatjacks, load-deformation (stress-strain)
that the flatjack in a slot in masonry will be capable of applying
properties may be obtained. Maximum compressive strengths
operating pressures up to 1000 psi (6.9 MPa). Metal flatjacks
may be measured in certain cases.
suitable for this purpose shall be made of type 304 stainless
steel sheet of 0.024 to 0.048 in. (0.61 to 1.2 mm) in thickness
4. Significance and Use
with welded seams along the edges, and incorporating hydrau-
4.1 Deformation and strength properties are measured only
lic inlet or outlet ports.
on the masonry between flatjacks. Boundary effects of the
5.1.4 Calibrate all flatjacks as described in Section 7 to
determine their pressure-applied load characteristics.
5.2 Hydraulic System—An electrically or manually oper-
This test method is under the jurisdiction of ASTM Committee C-15 on
Manufactured Masonry Units and is the direct responsibility of Subcommittee
ated hydraulic pump with hydraulic hoses is required. Hose
C15.04 on Research.
Current edition approved March 15, 1992. Published May 1992.
2 4
Solid-unit masonry is that built with stone, concrete, or clay units whose net A maximum operating pressure of 1000 psi (6.9 MPa) is adequate for older
area is equal to or greater than 75 % of the gross area. existing masonry, but flatjacks with higher operating pressures may be required for
Annual Book of ASTM Standards, Vol 03.01. more recently constructed buildings.
NOTICE:¬This¬standard¬has¬either¬been¬superceded¬and¬replaced¬by¬a¬new¬version¬or¬discontinued.¬
Contact¬ASTM¬International¬(www.astm.org)¬for¬the¬latest¬information.¬
C 1197
6.4 Prepare slots for circular and semi-rectangular flatjacks
using circular saws of sufficient radius to provide the depth
required (Fig. 2, dimension B). Use carbide or diamond tipped
blades to remove all mortar from the slot.
7. Calibration
7.1 A flatjack has an inherent stiffness which resists expan-
sion when the jack is pressurized. Therefore, the fluid pressure
in the flatjack is greater than the stress the flatjack applies to
masonry. A flatjack must be calibrated to provide a conversion
factor, K , to relate internal fluid pressure to applied stress.
m
7.2 Calibrate flatjacks in a compression machine of at least
100 kip capacity which has been calibrated according to
Practice E 74.
FIG. 2 Flatjack Configurations
7.3 Place a 2 in. (50 mm) thick steel bearing plate on the
lower platen of the compression machine. The bearing plate
connections shall fit the flatjack inlet port. Measure pressure
shall be of sufficient size to completely cover the flatjack being
using gages calibrated to a traceable standard having both an
calibrated. Place the flatjack on the lower bearing plate such
accuracy of 1 % of full hydraulic scale and an appropriate
that the edge of the flatjack with the inlet/outlet ports is
operating range. The hydraulic system shall be capable of
coincident with the edge of the bearing plate. Place steel
maintaining constant pressure within 1 % of full scale for at
spacers around the other edges of the flatjack. The thickness of
least 5 min.
the spacers shall be equal to approximately 1 ⁄3 times the
5.3 Displacement Measurement—Measure displacements
combined thickness of the two steel sheets used in fabrication
of the masonry with electronic instrumentation, for example, a
of the flatjack. Place the upper 2 in. (50 mm) thick bearing
Linearly Variable Differential Transformer (LVDT) mounted to
plate on top of the shims and flatjack, and align it to be directly
the surface of the masonry between the flatjacks, or by a
above the lower bearing plate. Position the bearing plate/
mechanical gage extensometer which measures the distance
flatjack/shim assembly on the lower platen such that the
between fixed gage points on the masonry as shown in Fig. 1.
centroid of the area of the flatjack is within ⁄4 in. (6 mm) of the
The method or device used to measure deformations shall be
axis of thrust of the test machine. The calibration setup is
capable of deformation measurements up to ⁄16 in. (5 mm).
illustrated in Fig. 3.
Deformation measurements shall have an accuracy of at least
7.4 Raise the moveable platen such that the non-moveable
60.005 % of gage length. Record measurements manually at
platen is in contact with the top bearing plate. Apply a pre-load
discrete intervals, or continuously by automatic data recording.
sufficient to provide full contact between the bearing plates and
5.4 Attachment of Measurement Devices—Attach brackets
the spacers, equivalent to 10 psi over the gross area of the
for mounting electrical displacement measuring devices or
flatjack.
gage points to be used with mechanical devices securely to the
7.5 The distance between platens must be held constant
surface of the masonry to prevent movement and ensure the
during the calibration procedure. Fix the displacement of the
required measurement accuracy. Use rigid adhesive for discs
test machine at this point if using a displacement controllable
and brackets and cementitious grout for plugs. If gage points
machine. If not, attach displacement gages (mechanical or
are used, the gage points shall have a conical depression at
electrical) such that the distance between platens established by
their center, compatible with the pointed elements of the
the procedures of paragraph 7.4 can be held constant when
extensometer. The angles of the depression of the cone and the
using a force-control test machine.
extensometer points shall be the same.
7.6 Pressurize and depressurize the flatjack three cycles
6. Preparation of Slots
with the maximum pressure in the flatjack not to exceed 1000
psi (2.069 MN/m ) nor the stress applied to the flatjack by the
6.1 Slots in masonry are normally prepared by removing the
compression machine to exceed 1000 psi (2.069 MN/m ) based
mortar from masonry bed joints to avoid disfiguring the
on the gross area of the flatjack.
masonry. Remove all mortar in the bed joint, that is, pressure
7.7 Increase the pressure in the flatjack in 50 to 100 psi
exerted by a flatjack shall be directly against the cleaned
(344.8 to 689.5 KN/m ) increments up to 1000 6 50 psi (6.895
surfaces of the masonry units.
2 2
MN/m 6 344.8 KN/m ) while holding the distance between
6.2 The plan geometry of the slot shall be similar to that of
platens constant. At each increment, record flatjack hydraulic
the flatjack being used. Plan dimensions of the prepared slot
pressure and force measured by the test machine.
shall not exceed those of the flatjack by more than ⁄2 in. (12
7.8 Calculate the load applied by the flatjack as internal
mm). Slots shall be parallel and aligned vertically, and shall be
pressure times gross flatjack area. Plot flatjack load versus load
separated by not more than 1.5 times the length of the flatjack.
measured by the test machine with the flatjack load on the
6.3 Prepare rectangular slots into which rectangular flat-
horizontal axis of the plot. The slope of the line equals the
jacks are to be inserted by drilling adjacent or overlapping
flatjack constant, that is, the conversion factor:
holes (stitch drilling) and subsequently using a drill, bar, or tool
to remove mortar and produce a slot of desired dimensions
K 5 P 4 P
m machine flatjack
with smooth
...
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