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Stabilizing 2-Wythe Tile Walls Using Adhesive Foam Filler
STABILIZING TWO-WYTHE TILE WALLS FOR SEISMIC RETROFIT USING
ADHESIVE FOAM FILLER
PART 1---GENERAL
1.01 SUMMARY
A. This procedure includes guidance on stabilizing two-wythe
clay tile walls with a light weight rigid adhesive filler
in the cavity between the wythes for seismic retrofit.
NOTE: THIS PROCEDURE SHOULD BE EXECUTED BY A SPECIALIST
TRAINED IN MASONRY STABILIZATION AND IS RECOMMENDED FOR
USE IN VERY LIMITED APPLICATIONS.
B. The filler material shall adhere to clay tile and have
strength and rigidity properties so that the tile-foam
composite will respond to earthquake shaking as a wall of
thickness equal to the existing out-to-out dimensions of
the two-wythe wall.
C. See 01100-07-S for general project guidelines to be
reviewed along with this procedure. These guidelines
cover the following sections:
1. Safety Precautions
2. Historic Structures Precautions
3. Submittals
4. Quality Assurance
5. Delivery, Storage and Handling
6. Project/Site Conditions
7. Sequencing and Scheduling
8. General Protection (Surface and Surrounding)
These guidelines should be reviewed prior to performing
this procedure and should be followed, when applicable,
along with recommendations from the Regional Historic
Preservation Officer (RHPO).
1.02 REFERENCES
A. American Society for Testing and Materials (ASTM)
www.astm.org
1.03 SUBMITTALS
A. Product Data: Submit the manufacturer's product
information including identification, packing, component
mixing quantities and injection procedures curing times,
workman's safety precaution, and by-products released to
the atmosphere.
B. Test Report: Submit the report of a testing program in
compliance with Part 3 of this specification.
C. Injection procedure: Submit data on injection procedures
and equipment. Include proposed locations, spacings and
sizes of injection ports.
D. Submittals shall be reviewed by the Architect and
approved by the Contracting Officer before proceeding.
1.04 QUALITY ASSURANCE
A. Engage a testing laboratory acceptable to the RHPO.
B. Testing laboratory responsibilities:
1. Observe preparation of the walls for injection.
2. At the beginning of the injection work, observe
mixing and injection procedures for compliance with
these specifications and manufacturer's
instructions.
3. Upon completion of the project, drill and observe
12 observation holes, (2 in each wall at each
level) at locations to be selected by the
Architect; confirm filling of the void between
wythes with foam.
C. Mock-Ups:
NOTE: THE TESTING PROGRAM IS TO ESTABLISH ACCEPTABLE
MATERIAL AND DEMONSTRATE THE INJECTION PROCEDURE.
ALTERNATIVE MATERIALS AND PROCEDURES COMPLYING WITH PART
1 AND PART 2 MAY BE PROPOSED. DO NOT PROCEED WITHOUT
REVIEW BY THE RHPO AND APPROVAL BY GSA.
1. Obtain clay tile units from the Building. Protect
the units from damage and surface contamination.
2. Clean the surfaces that will receive mortar with a
wire brush. Do not clean the surfaces to which the
adhesive foam will be applied.
3. Construct two 2-wythe test panels and allow to cure
for 28 days. Install the units with the internal
cells horizontal.
4. Construct end forms to enclose a void between the
tile wythes. The end forms shall not connect to
the tile units in a way that prevents the units
from deflecting outward under pressure from within
the void. The forms shall be tight enough to
confine the adhesive foam placed in lifts.
Coordinate with the foam installer for form
pressure and anticipated confinement requirements.
5. Place two component epoxy adhesive foam fill into
the void in 12" lifts through holes core drilled
into one wythe. (The holes for foam placement may
be drilled prior to constructing the test panels).
The depths of lifts shall be limited to prevent
foam pressure from causing the wythes to bow
outward and shall be the same as will be used in
the building. Fill to within 2" of the top of the
panel.
6. Allow the foam fill to cure as recommended by the
manufacturer. Remove the forms.
7. Test the panels by loading to ultimate horizontal
load.
8. Evaluation: The panels shall break by cracking
horizontally through the panel at about mid-height,
without crushing of the foam or delamination of the
foam from a tile surface except in that offset zone
between the crack path through the tile masonry. A
break other than described above is not acceptable.
9. Report for each test panel:
a. Test set-up
b. Horizontal load at cracking
c. Horizontal load after cracking
d. Location and orientation of crack
e. Any delamination between foam and tile
f. Any visible distortion of foam under load
g. Any visible distortion of foam after cracking
PART 2---PRODUCTS
2.01 MANUFACTURERS
A. Delta Plastics
www.deltafoam.com
2.02 MATERIALS
A. Fill Material:
1. Two-component epoxy adhesive foam complying with
the testing program of Part 3, such as "Bisfoam-3 A & B" (Delta Plastics), or approved
equal.
2. The cured foam, when exposed to an open flame, will
char on the contact areas with little damage or
deformation of the foam structure.
3. The foam is to have a density value of less than 75
along with a flame spread rating of less than 19.
CAUTION: THE SMOKE EMITTED MAY CONTAIN
DECOMPOSITION PRODUCTS OF CARBON, HYDROGEN, WATER,
AND TRACES OF FLUORINE, BUT MAY HAVE ONLY A VERY
LOW OFFENSIVE ODOR QUALITY.
B. Form Materials: Materials to confine the foam and
prevent flow out of the wall shall be as follows:
1. If least dimension of hole is less than 1-1/2 inch, use
Type N mortar complying with ASTM C270. Fill the
hole to a depth equal to 1-1/2 times the exposed
least dimension.
2. If least dimension of hole is 1-1/2 inch or greater,
use unit brick masonry (common brick) and type N
mortar complying with ASTM C270; minimum thickness
of unit masonry form shall be at least the
thickness of the existing clay tile wythe in which
it is placed.
3. If least dimension of hole is 1inch maximum, use
plastic foam joint filler: diameter/injection/preformed,
compressible, resilient, non-waxing, non-extruding
strips of plastic foam of material as recommended by
sealant manufacturer and of size, shape and density to
control sealant depth and produce optimum sealant
performance.
C. Brick: Brick used for filling holes may be salvaged from
the building. New brick shall conform with ASTM C62,
grade MW.
2.03 EQUIPMENT
A. Masonry drill
B. Injection equipment
PART 3---EXECUTION
3.01 PREPARATION
A. Surface Preparation:
1. Expose wall surface to permit observation of voids
that would prevent confinement of the foam.
2. Close and repair breaks and holes to confine the
foam to the cavity between wythes of the wall,
except at holes of less than 1-1/2 inch in least
dimension, foam may be permitted to flow to within
1-1/2 times the holes least dimension from the face
at the wall.
3. Drill injection/verification holes through one
wythe at 12 inch maximum on center horizontal and
vertical spacing. Injection/verification holes may
be made in head or bed joints.
3.02 ERECTION, INSTALLATION, APPLICATION
A. Begin injection through injection/verification ports at
the lowest course of tile.
B. Inject in approximately 12 inch lifts. Inject into injection
holes until flow of foam is verified at adjacent holes at
the same level. Plug verification holes with joint
filler to confine the foam flow.
C. Complete each lift for the full length of all walls
before proceeding to the next lift. Allow each lift to
cure before proceeding to the next lift.
D. Clean-up spills as they occur. Protect finish materials
from damage.
END OF SECTION
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