|Title of Invention||
"WATERPROOFING MEMBRANES FOR CIVIL STRUCTURES"
|Abstract||A pre-formed, shaped waterproofing membrane (10) comprising a carrier support sheet (12) having first and second opposed major faces and, disposed over said first major face, a pressure-sensitive waterproofing adhesive layer (14) operative to bond with post cast concrete, characterized by said shaped membrane having a three-dimensional contour surrounded by a flat collar portion (13), wherein said three-dimensional contour (11) extends outwardly from said first major face and is of sufficient size to cover a surface irregularity in a building or civil construction surface, and wherein said three-dimensional contour is dome-shaped, cylinder-shaped, cone-shaped, pyramid-shaped or box-shaped.|
|Full Text||THREE-DIMENSIONAL REVERSE TANKIMG MEMBRANES
INVENTORS: Jyoti Sefh, Jay Kellett, M. S. Chetan and Neal S. Berke
Field of the Invention
The present invention relates to reverse tanking waterproofing
membranes which bond to freshly poured concrete, and more particularly to
membranes having three-dimensional contours for creating unified moisture
barriers in and around detail areas and other surface irregularities.
Background of the Invention
Waterproofing membranes having flexible plastic sheets for carrying a
preformed, pressure-sensitive adhesive layer have been used for a number of
years to provide protection to existing building surfaces. The adhesive layers
are typically made of rubber-modified bitumen, which is aggressively sticky,
and is covered by a release sheet that is removed before attaching the
membrane to the substrate surface.
A technique for "reverse tanking" waterproofing is described in US
Patent 4,994,328 of Cogliano (bituminous adhesive) and US Patent 5,316,848 of
Bartlett et al. (non-bituminous synthetic adhesive). According to this
technique, the waterproofing membrane is first attached with the back side of
its carrier sheet against a "formwork" (i.e., concrete mold usually formed by
wooden boards joined together). Consequently, the waterproofing adhesive
layer faces outwards. A concrete structure is created by casting concrete
against the membrane-covered formwork surface, and this may be referred to
as "post cast" or "post applied" concrete. The adhesive layer is covered by an
elastomeric protective coating layer, a particle coating layer, or mixture or
arrangement of both (i.e., either individually, mixed together as one layer, or
arranged as discrete layers), to protect the adhesive from dirt and damage.
This protective coating layer (whether of polymeric or particle coating) also
operates to decrease the tack of the adhesive. The outer surface is further
protected by a release sheet liner (that must be removed before fresh concrete
is poured against the adhesive/protective coating layers). After curing, the
concrete is bonded with the adhesive/protective coating layers, and thus a
waterproofing bond is achieved in "reverse" order.
Hence, in the world of "reverse tanking" waterproofing, it can be said
that the waterproofing is "pre-applied" because it precedes the concrete
structure; and, in turn, the concrete is said to be "post cast" or "post applied"
because it follows installation of waterproofing.
Reverse tanking is further discussed in US Patent Nos. 5,496,615 and
6,500,520 which teach using particle coating layers. In the '615 patent,
inorganic particles are used to resist foot traffic when the membrane is
installed on a horizontal surface. In the '520 patent, particles are applied on
top of an adhesive layer to enhance bonding with concrete by reacting with
calcium hydroxide generated during hydration of cement.
One of the difficulties of reverse tanking is achieving continuity of
waterproofing in detail areas (i.e., surface irregularities), and especially in
"tieback" detailing. Tiebacks are the terminal ends of rods or cables
supporting the formwork and found protruding at intervals through the
formwork surface. Other surface irregularities include penetration areas,
such as where pipes or pile caps extend through the formwork.
Fig. 1 illustrates the present process used in the industry for
waterproofing "tiebacks" on concrete formworks. Drainage mats or sheets,
which usually involve a fabric attached to a cuspated core sheet, are placed
against the wooden formwork, and covered by sheets of reverse tanking
waterproofing membrane, previously described above. Such sheet materials
are available from Grace Construction Products, Cambridge, Massachusetts,
under the trademarks HYDRODUCT® (drainage) and PREPRUFE®
(waterproofing membranes). These sheet materials are required to be cut and
arranged to surround the area on the formwork occupied by the tieback,
which can be as large as a man's chest.
As shown in Fig. 1, a wooden or metal box must be fabricated and
fitted over the tieback. The box is fastened to the formwork, such as by
screws and brackets, with a bead of adhesive for sealing around the edges
against the formwork. The box is filled with liquid mastic or mortar cement
to prevent twisting or collapse of the box due to the poured concrete.
As shown in Fig. 2, the box is covered with waterproofing strips. The
strips are available as a double-sided adhesive "tape" from Grace
Construction Products under the PREPRUFE® brand name. One side has a
tacky adhesive that sticks onto the box and surrounding formwork; the other
side has a coated adhesive layer for bonding to post cast concrete. Although
Figs. 1 and 2 illustrate a finished tape "box" shape, the actual waterproofing
of the box with strips requires painstaking labor. The tape strips must be
overlapped to provide a continuous barrier over and around the tieback.
Fabricating, fastening, and waterproofing each box at a tie back detail requires
about 30 minutes or more. In formwork installations that exceed one
thousand square feet, one may confront one hundred tiebacks. Providing
waterproofing for such detail areas as these would thus require days of labor.
In view of the foregoing disadvantages, a novel method and
waterproofing membrane system are needed for decreasing labor costs in
waterproofing installations wherein tiebacks, pipe penetrations, pile cap
penetrations, and other surface irregularities are encountered.
Summary of the Invention
In surmounting prior art disadvantages, the present invention provides
"reverse tanking" waterproofing for detail areas and other surface
irregularities. An exemplary waterproofing membrane of the invention,
having a three-dimensional contour surrounded entirely or partially by a flat
collar portion, can be positioned over tiebacks or other surface irregularities,
and seamed with conventional reverse tanking membranes to provide a
continuous waterproofing barrier. Preferably, such shaped membranes are
used in combination with correspondingly shaped molded support structures
to prevent the membranes from collapsing under the weight of post cast
concrete (i.e., concrete which is cast against them after they are installed).
In an exemplary method of the invention, a molded rigid plastic or
metal dome is positioned over a tieback and fastened to the formwork, and a
"shaped" waterproofing membrane having a corresponding dome shape is
fitted over the support and seamed with adjacent "sheet-form" waterproofing
membranes on the formwork to provide a continuous moisture barrier. The
term "shaped" will be used to define the reverse tanking membranes of the
invention, in contrast to the term "sheet-form" which will be used to define
conventional reverse tanking membranes (typically supplied in roll form).
As another example, a waterproofing membrane having a threedimensional
shape, such as a circular- or conical-shaped sleeve, surrounded
by a contiguous flat collar portion, may be employed for waterproofing
around penetrations such as pipes and pile caps. Three-dimensional shaped
waterproofing membranes, having shapes such as domes, cones, cylinders,
pyramids, or other three-dimensional forms, will save several steps otherwise
needed for providing a continuous barrier at penetration joints. Such
membranes may have at least one or both major faces coated with one or
more conventional waterproofing adhesive layers (e.g., rubberized asphalt,
synthetic polymeric adhesives, clay-based adhesives, etc.) which are operative
to bond with fresh concrete.
The present invention is also directed to waterproofed structures
formed by the methods described herein, as well as to shaped waterproofing
membranes and methods for making such membranes. An exemplary
method for making shaped membranes comprises: providing a laminate
having a carrier support sheet and, contiguous therewith, a continuous
pressure-sensitive waterproofing adhesive layer, with optionally a protective
polymeric coating layer and/or particle coating layer over the adhesive layer;
and molding the laminate as one piece to provide a shaped waterproofing
membrane having a three-dimensional contour that is entirely or partially
surrounded by a flat collar portion. Preferably, the carrier support sheet
comprises a polyolefin blend tiiat is operative to be molded below SOOT.
More preferably, the support sheet comprises a blend of LDPE and HDPE
resin, and the pressure-sensitive adhesive is a non-bituminous synthetic
adhesive (e.g., SIS).
The choice of materials is such that the laminate may be thermally
molded into a three-dimensional contour at temperatures below 300°F, and
more preferably below 250°F, without destroying the continuity of the
pressure-sensitive adhesive layer or protective coating layer, nor the ability of
these layers to provide a waterproofing bond with post cast concrete.
Other advantages and features of the invention are discussed in further
Brief Description of Drawings
Fig. 1 is an exploded, side-view plan diagram of a PRIOR ART method
for waterproofing detailed areas, such as tiebacks, in a concrete formwork;
Fig. 2 is another perspective plan diagram of the PRIOR ART method
illustrated in Fig. 1;
Fig. 3 is diagram of an exemplary shaped waterproofing membrane of
the invention shown with an optional exemplary shaped supporting device
for covering a tieback or other surface irregularity; and
Fig. 4 is a diagram of another exemplary shaped waterproofing
membrane of the invention.
Detailed Description of Exemplary Embodiments
The waterproofing systems described herein are intended to bond with
fresh cementitious compositions that are cast against them and allowed to
harden. Cementitious compositions, such as concrete or mortar cement,
which is applied this way to the waterproofing membranes, are sometimes
referred to as being "post cast" or "post applied."
The terms "cement" and "cementitious composition" are used to refer
to dry powders as well as to pastes, mortars, grouts, and concrete
compositions comprising a hydratable cement binder. The terms "paste",
"mortar" and "concrete" are terms of art: pastes are mixtures composed of a
hydratable cement binder (usually, but not exclusively, Portland cement,
masonry cement, or mortar cement). Mortars are pastes additionally
including fine aggregate (e.g., sand), and concrete are mortars additionally
including coarse aggregate (e.g., crushed gravel, stone). Cementitious
compositions are typically formed by mixing hydratable cement, water, and
fine and/or coarse aggregate.
As shown in Fig. 3, an exemplary "shaped" waterproofing membrane
10 and optional exemplary supporting structure 30 can be used to provide a
continuous waterproofing barrier over a tieback 40 or other surface detail on
the construction surface before concrete is post cast against it.
As illustrated in the magnified view (enlarged circle) in Fig. 3, the
waterproofing membrane 10 comprises at least one carrier support sheet 12
having first and second major opposing faces, and, attached to a first major
face thereof, at least one continuous pressure-sensitive waterproofing
adhesive layer 14 operative to bond with post cast concrete or mortar.
Optionally, but preferably, a protective layer 16, such as an elastomer
coating, a particulate layer, or a mixture thereof (e.g., particles mixed into the
elastomer) or arrangement thereof (e.g., discrete particle layer on top of or
partially embedded into an elastomer layer) operates to protect the adhesive
layer 14 from dirt and debris.
For example, the carrier support sheet 12, pressure-sensitive
waterproofing adhesive layer 14, and optional protective layer 16 of the may
comprise materials and incorporate thickness dimensions taught in US
Patents 5,316,848 and 5,496,615 of Bartlett et al., wherein it was taught that the
carrier support sheet may be fabricated from a thermoplastic, rubber, or metal
in the form of a continuous film, a woven material, or a non-woven material.
Thermoplastics particularly suited for use in the present invention include
high density polyethylene (HOPE), polyethylene teraphthate (PET),
polystyrene (PS), polyvinyl chloride (PVC), polyamides (PA), or combinations
While HDPE was the carrier support sheet material preferred by
Bartlett et al., the present inventors prefer using, for making shaped
waterproofing membranes 10 of the present invention, a carrier support sheet
12 in the form of a continuous film made from a polyolefin blend. Most
preferably, the blend comprises low density polyethylene (LDPE) and high
density polyethylene (HDPE). The carrier support sheet 12 can be made by
sheet-extruding the polymer or polymer blend through a sheet die and/or
calendaring the sheet between opposed rollers to achieve a relatively uniform
thickness. Use of LDPE in the polyolefin'blend is preferred due to increased
ease of thermal molding (thermoforming). This is because the preferred
method of the present invention involves thermoforming the carrier support
sheet 12 and preformed waterproofing adhesive layer 14, and optionally a
protective layer 16, altogether as one integral unit, e.g., as a unified laminate.
Other polyolefin blends may be possible for the carrier support sheet
12, such as very low density polyethylene (VLDPE) and HDPE or
While it is possible to mold the carrier support sheet 12 separately,
followed by subsequently applying the waterproofing adhesive 14 and
optional protective layer 16 as separate coatings, the use of thermal molding
("thermoforming") to obtain a three-dimensional shaped waterproofing
membrane 10 from a unified laminate will save time and provide economic
advantages. The thickness of the individual layers may change during
thermoforming, which is the preferred method of making the shaped
membranes, and so initial thicknesses of the layers should be chosen with this
fact in mind.
For example, the waterproofing membrane laminate 10 can be
manufactured by coating or extruding onto a paper or plastic release sheet
(not shown) first the protective layer 16 (e.g., polymer coating), followed by
coating or extruding the waterproofing adhesive layer 14 (e.g., SIS), and then
the resultant laminate can be applied to the carrier support sheet 14; and the
release sheet can be removed just before the membrane laminate 12/14/16 is
thermoformed to provide the shaped waterproofing membrane 10.
Alternatively, the adhesive 14 and protective 16 layers can be coated or
extruded directly onto the carrier support sheet 12, and then the release sheet
liner (not shown) can be applied, such as by calendaring it onto the laminate
whereby the calendaring operation ensures a uniform total thickness of the
membrane. In either case, the release sheet liner is removed before molding
(e.g., thermoforming) of the membrane to provide the three-dimensional
In still further exemplary methods and membranes of the invention,
the adhesive 14 and protective coating layer 16 (polymeric) can be coextruded
simultaneously between a carrier support sheet 12 and release sheet.
For example, a continuous operation may involve co-extruding the adhesive
and protective coating layers between the carrier support sheet 14 and release
liner as they are being bed between rollers which laminate them together.
Again, the release sheet is used for purposes of making the laminate and
protecting the adhesive/protecting coatings until the thermoforming stage,
whereupon it is preferably removed and discarded.
"In exemplary methods of the invention, the 'thermoforming stage
should preferably involve temperatures under 300°F in order to prevent
damage to the pressure-sensitive adhesive layer (and protecting coating layer)
which must retain integrity, sufficient thickness, and ability to bond with and
to waterproof post cast concrete. It is preferable to subject the carrier support
sheet 12 side of the membrane 10 to a temperature mat is higher than the
adhesive layer 14 side because it is the carrier support sheet 12 that primarily
requires thermal softening for purposes of shaping, whereas the adhesive
layer is more easily conformable and would require less heat for molding.
The thickness of the carrier support sheet 12 is preferably 10-150 mils thick
and more preferably 30-80 mils thick.
An exemplary three-dimensional contour 11, shown as a dome shape
in Fig. 3, may have an average diameter and height of 10 cm - 100 cm or
larger, depending on the size of the surface detail, and is entirely or partially
surrounded by a flat collar portion 13. The thickness and materials of the
carrier support sheet 12 are chosen such that, in combination with the
waterproofing adhesive layer 14 and protective coating layer 16, the average
temperature needed for thermoforming the shaped membrane 10 (as a
laminate) does not exceed 300°F (all temperatures herein being described in
Although the pressure-sensitive waterproofing adhesive layer 14 may
comprise a bituminous adhesive, the present inventors prefer using synthetic
non-bituminous adhesives. Such synthetic adhesives may include butyl
rubber, polyisobutylene, polyisobutyl rubber, acrylic (or acrylate), vinyl ether
based adhesives, styrene-isoprene-styrene (SIS), styrene-ethylene-butylenestyrene
based (SEES), styrene-butadiene-styrene (SBS), or mixtures thereof.
Another possible adhesive is ethylene propylene diene monomer. Most
preferred, however, are pressure-sensitive hot-melt adhesive block
copolymers of SIS. Preferred adhesive layers should also withstand melting
temperatures in the range between 160°F and SOOT (for a duration of between
2 seconds to 2 minutes) without losing their continuous layer form and
without the adhesive layer 14 (and optional protective coating layer 16) losing
the ability to provide a bond with post cast concrete.
The pressure sensitive adhesive layer 14 can optionally contain typical
additives, such as light absorbers (i.e., carbon black, benzotriazoles, etc.), light
stabilizers (i.e. hindered amines, benzophenones), antioxidants (i.e. hindered
phenols), fillers (i.e. calcium carbonate, silica, titanium dioxide, etc.),
plasticizers, rheological additives, and mixtures thereof. Preferred synthetic
adhesive layers contain light absorbers, light stabilizers, and antioxidants.
As discussed in US Patents 5,316,848 and 5,496,615, the adhesion to
post cast concrete is improved when the synthetic adhesive layer 14 has a
penetration greater than about 30 decimillimeters (dmm) (150 g, 5 sec., 70°F)
as measured according to ASTM D 5-73, incorporated herein by reference.
The "adhesive" nature of the synthetic pressure sensitive adhesive 14 has the
added benefit in that side laps and end laps of the membrane 10 are easily
formed. The average thickness of the synthetic adhesive layer may be 10-150
mils, more preferably 20-100 mils, with 50-100 mils being most preferred.
In preferred membranes and methods of the invention, the shaped
waterproofing membrane 10 further comprises a protective coating layer 16 to
decrease tack and to protect the adhesive 14 from dust, dirt and the elements
(particularly sunlight). At the same time, the protective layer 16 does not
defeat the ability of the membrane 10 to form a fully adhered strong bond
with post cast concrete. The protective coating layer 16 may comprise, for
example, a polymer coating, a layer of particulate matter, or a mixture thereof.
Exemplary polymer coatings may comprise sytrene butadiene rubber based
(SBR) coatings, carboxylated SBR based coatings, acrylic based coatings (e.g.,
an acrylate), polyvinylidene chloride based (PVDC) coatings, polyvinyl
chloride based (PVC) coatings, ethylene vinyl acetate copolymer based (EVA)
coatings, ethylene ethyl acetate copolymer based (EEA) coatings,
polychloroprene based coatings, polyester based coatings, polyurethane
based coatings, styrene-isoprene-styrene based (SIS) coatings, styrenebutadiene-
styrene based (SBS) coatings, styrene-ethylene butylene-styrene
based (SEBS) coatings, or a mixture thereof.
Preferred protective coating layers 16 are acrylic based coatings, and
most preferred are styrene butylacrylate based coatings. Protective layers 16
which are elastomeric in nature are preferred. As used herein, the term
"elastomeric" means and refers to an elastic polymer having a property
similar to those of vulcanized natural rubber; namely, to stretch when pulled
and to retract rapidly to approximately original length when released.
Elastomeric acrylic based coatings are preferred, and elastomeric styrene
butylacrylate based coatings are most preferred. The average thickness of the
protective layer 16 may be anywhere from 1-80 mils, and more preferably 5-60
The protective layer 16 may optionally contain typical additives and
have a penetration value similar to those described for the pressure-sensitive
adhesive layer 14 described above. Protecting layers 16 made from polymeric
materials (e.g., butyl acrylate) preferably include titanium dioxide or zinc
oxide for protection from sunlight, as well as fillers (e.g., talc, calcium
carbonate, sand, slate dust) to enhance scuffing- and abrasion-resistance.
As just mentioned, the protective layer 16 may comprise inorganic
particles which are roll pressed onto the waterproofing adhesive layer 14
(where no polymer protective coating is used) and/or mixed into the a
polymer protective coating 16 material. A number of particulate materials
believed suitable for this purpose are catalogued in US Patent 5,496,615 of
Bartlett et al. and US Patent 6,500,520 of Wiercinski and Seth, as previously
referenced above. For example, Bartlett et al. disclosed particles of calcium
carbonate, cement, talc, sand, granite dust, slate dust, clay, titanium dioxide,
and carbon black; while Wiercinski and Seth disclosed particles of aluminum
oxide trihydrate, silica dioxide, fly ash, blast furnace slag, silica fume, alkali or
alkaline earth metal nitrites, nitrates, halides, sulfates, hydroxides,
carboxylates, silicates, aluminate, or mixtures thereof. Combinations of such
particles (e.g., calcium carbonate and talc) are also contemplated.
Thus, the protective coating 16 layer may be made of a polymeric
coating applied as a liquid and allowedTo dry; may be made of a mixture of
polymeric coating material having particulates and/or other additives
incorporated into the polymer; or may be made solely of particles that are
applied by rolling them onto and embedding the particles entirely or partially
into the outer adhesive layer 14 and/or outer polymer coating layer 16.
As shown in Fig. 3, an exemplary shaped waterproofing membrane 10
preferably has a three-dimensional contour 11 such as as a dome, surrounded
partially or entirely by a flat collar portion 13. The flat collar portion 13 has
edges (such as designated at 15) which are preferably straight in nature to
permit a waterproofing tape to be used conveniently to provide a water-tight
seam with "sheet-form" (i.e., conventional reverse tanking) waterproofing
membranes on the formwork or other substrate surface.
As shown in Fig. 1, an exemplary supporting structure 30 has a
corresponding dome shape 31 also is entirely or partially surrounded by a flat
collar portion 33 useful for fastening the structure 30 onto a formwork or
other mounting surface. The support structure 30 may be thermoformed or
stamped from a thermoplastic sheet material, such as ABS high impact
polystyrene, poly(vinyl) chloride, polypropylene polyethylene, and others.
The support structure may also be made from sheet metal such as steel, (e.g.,
stainless) aluminum, copper, tin, or other metals. Many of these metals can be
thermoformed or stamped into shape relatively conveniently. The average
thickness of the support structure 30 is about 10-200 mils and more preferably
20-100 mils. While various thermoplastics may be used, such as polyvinyl
chloride (PVC), some materials such as high density polyethylene, while
thermoformable, may require extra thickness in order to withstand the force
of post cast concrete, and this extra thickness may present manufacturing
difficulties during thermoforming because the added thickness will require
higher melting temperatures or longer dwell time (in a heated mold) to soften
the plastic, and this could lead to excessive heating and scorching of the
material. Thus, preferred thickness will often depend upon the choice of
The thermoplastic material used for the support structure 30 should
ideally withstand nails, staples, or other fasteners being driven through the
flat collar portion to secure the structure to formwork. This does not rule out
using brittle materials which shatter, however, because such materials can
also be attached using alternative means (e.g., adhesives, drilled holes, etc.).
In addition to dome or hemispherical shapes, other thermof ormed or stamped
three-dimensional shapes such as cylinders, boxes, pyramids, etc., can be
employed, but dome shapes are preferred because they are least vulnerable to
distortion or twisting caused by the wet concrete or mortar cast against the
membrane-covered 10 supporting structure 30. Furthermore, a rounded
shape provides better flow of the concrete around the support structure (30),
thus better enabling the consolidation of the concrete, and improving or
ensuring bonding between the concrete and support structure (30). It is
preferable to have fewer sharp edges or creases which may lead to
weaknesses in the surrounding concrete.
Although the support structure 30 (dome) may be filled with material,
such as a polyurethane foam or mortar cement, to resist collapsing under the
weight of concrete, it is believed that the thickness of the support material and
the material chosen (e.g., synthetic polymer, metal, or combination thereof)
may be such as to allow the support structure 30 by itself, without filling its
cavity, to support the weight of post cast concrete. Nevertheless, for
extremely large formwork installations, wherein pressures of huge volumetric
amounts of post cast concrete are involved, it may be necessary to fill dome
structures 30 particularly at the bottom of the f ormwork where pressures may
be greatest, but this can be conveniently accomplished such as by drilling a
small hole in an installed dome, filling the dome through the hole with
material (e.g., polyurethane foam which becomes rigid), and then sealing the
hole with two-sided PREPRUFE® tape.
In preferred methods of the invention, the supporting structure 30 is
molded using the same mold as used for providing the three-dimensional
contour in the shaped waterproofing membrane 10 (to be further described
The supportive dome structure 30, which similarly has a three dimensional
contour portion 32 surrounded entirely or partially by a flat
collar portion 34, serves not only to support the shaped waterproofing
membrane 10 when it is installed over a tieback 40 or other surface detail, but
also serves for protecting the similarly shaped membrane 10 during shipment.
For example, the supportive dome structure 30 can be placed into a box
situated on the outer first face of the membrane 10 to protect the adhesive side
of the membrane (i.e., the rigid dome is placed over the soft dome), and thus
the shaped membrane 10 is "tucked under the hat," so to speak. At the
construction site, the order is reversed, with the supportive dome structure 30
being fitted over the tieback and fastened onto the formwork 40 or other
substrate surface by nails or other fasteners driven through the flat collar
portion 34 and into the underlying formwork, and then this is followed by
fitting the shaped waterproofing membrane 10 over the dome support 30.
The membrane 10 can be attached it to the supporting dome structure 30
and/or surrounding formwork or adjacent conventional membranes by any
means known, such as by using a conventional mastic or other adhesive.
It is envisioned that shaped membranes 10 with domes 30 of
corresponding size can be packaged together as sets, much in the manner of
stacking identically shaped hats or bowls. Moreover, such
membrane/support sets can be variously sized (in the manner of stainless
steel salad bowl sets) for situations wherein various-sized tiebacks or other
surface irregularities are encountered.
Accordingly, in a further exemplary embodiment, a plurality of shaped
waterproofing membranes 10 are fitted with correspondingly shaped support
structures 30 within the same packaging (e.g., shipping) carton or box, similar
to the way in which dispensable paper drinking cups are sold stacked
together in packaging. Preferably, each shaped membrane 10 is fitted into its
corresponding support structure 30, and this "set" can be fitted within
another "set" and thus easily removed from the packaging carton, one set at a
time, as the need dictates. Moreover, the ability to stack the "shap'ect"
membranes allows them to be conveniently shipped or transported alongside
the "sheet-form" membranes with which they will be used for typical reverse
tanking applications. For example, a shipment of both "shaped" and "sheetform"
(conventional) membranes (supplied in roll form in carton) can be
bundled together (such as by using plastic wrapping, binding materials, etc)
for transport the cartons together conveniently to the construction site.
Alternatively, rigid domes (or other three-dimensional shapes) can be
used as the waterproofing membranes themselves, such as by first stamping
or thermoforming a rigid sheet into the desired three-dimensional shape (e.g.,
dome or pyramid surrounded by one or more collar portions or flanges), and
subsequently this structure is coated or layered with a coating for bonding to
fresh concrete. For example, the coating may comprise rubberized asphalt, a
synthetic polymer adhesive (e.g., SIS, SEES, acrylic, polyurethane, etc.), a clay
based adhesive (e.g., bentonite, smectite), or mixture thereof.
The outer edges 15 of the shaped waterproofing membrane 10 are
preferably straight so that the membrane can be conveniently overlapped
with those of a conventional reverse tanking waterproofing membrane.
Furthermore, the shaped membrane 10 (Fig. 3) and conventional membranes
installed onto the formwork (See e.g., Fig. 1 PRIOR ART) can be seamed
together by using two-sided reverse tanking tape (e.g., Grace PREPRUFE
tape) to provide a continuous barrier between and around the area
surrounding the tieback 40.
In further exemplary embodiments of the invention, it is possible to
provide a membrane that combines the properties of both the shaped
membrane 10 and support structure 30, such as by coating the waterproofing
adhesive layer 14 directly onto a rigid three-dimensional contour surrounded
entirely or partially by a flat collar portion, followed by optionally coating a
protective coating layer onto the adhesive layer. This method is less desirable
than thermoforming a single laminate because it would be more timeconsuming
to make (at the plant) or "assemble (at the construction site).
In this connection, the present inventors believe that it will be most
convenient for applicators to fasten a thermoformed dome support 30 in place
over the tieback (e.g., by mailing the flat collar portion into the formwork);
and then to cover the support dome with a correspondingly "shaped"
waterproofing membrane 10 that is easily sealed with 'sheet-form"
(conventional) reverse tanking membranes: using just four strips of tape. The
installation time is estimated to only a few minutes, from removal of the
pieces from the shipping carton. This is far less than what is required by
present industry practice as earlier described in the background.
The present invention therefore relates to the provision of a unified
waterproofing barrier by providing a shaped waterproofing membrane 10,
and relates to a well as the method for constructing such unified barriers on
building and civil engineering surfaces using the shaped membrane 10 in
combination with "sheet-form" (conventional) reverse tanking membranes.
With this distinction between conventional "sheet-form" and "shaped"
reverse tanking membranes in place, an exemplary method of the invention
comprises: providing at least one "sheet-form" waterproofing membrane
comprising a carrier support sheet with first and second opposed major faces,
and, disposed over a first major face thereof, a pressure-sensitive adhesive
layer operative to bond with post cast concrete; and providing at least one
"shaped" waterproofing membrane (e.g., Fig. 3) comprising a carrier support
sheet 10 having first and second opposed major faces, and, disposed over a
first major face thereof, a pressure-sensitive waterproofing adhesive layer 14
operative to bond with post cast concrete, the shaped membrane having a
three-dimensional contour 11 surrounded (entirely or partially) by a flat collar
portion 13 operative to overlap and form seams with the at least one sheetform
Preferably, both the sheet-form and shaped waterproofing membranes
further comprise a protective coating layer 16, such as an elastomeric
polymeric coating and/or a particle layer. More preferably, the carrier
support sheet 12, adhesive layer 14, and protective layer 16 of the shaped
membrane 10 are thermoformed together as a single piece laminate.
In further exemplary methods, a support structure 30, preferably
molded from the same mold used for thermoforming the shaped
waterproofing membrane 10, is first installed onto a formwork or other
mounting surface, so that the shaped membrane can be positioned over the
installed support structure 30.
Fig. 4 illustrates another exemplary shaped waterproofing membrane
50 of the invention which is installed around a penetration 60 (e.g., pipe) in
the building or civil construction surface 62. In this case, the threedimensional
contour 51 is cylindrically shaped and surrounded by a flat collar
portion 53 molded from the same sheet material. The outer surface of the
cylinder 51 and upper face of the flat collar portion 53 are covered by a
waterproofing pressure sensitive adhesive and optional protective coating
(similar to the layers illustrated in magnified view in Fig. 3). The flat collar
portion 53 has preferably straight edges (as designated at 55) to provide quick
seaming, using conventional two-sided reverse tanking tape (e.g.,
PREPRUFE® brand), with "sheet-form" (conventional) reverse tanking
membranes (not shown) that may be installed on the substrate surface 62.
In a further exemplary embodiment, the cylinder form 51 can be
replaced by a cone shape. The top of the cone can be cut at the desired cone
height to achieve an opening diameter corresponding to the diameter or size
of the object (pipe 60, pile cap, etc.) to be waterproofed. The use of the threedimensional
cylinder shape 51 (Fig. 4) or cone shape will also save
considerable labor at the construction site, because the waterproofing
membrane 50 would require
The foregoing embodiments and illustrations are provided for
illustrative purposes only.
1. A pre-formed, shaped waterproofing membrane (10) comprising a carrier support sheet (12) having first and second opposed major faces and, disposed over said first major face, a pressure-sensitive waterproofing adhesive layer (14) operative to bond with post cast concrete, characterized by said shaped membrane having a three-dimensional contour surrounded by a flat collar portion (13), wherein said three-dimensional contour (11) extends outwardly from said first major face and is of sufficient size to cover a surface irregularity in a building or civil construction surface, and wherein said three-dimensional contour is dome-shaped, cylinder-shaped, cone-shaped, pyramid-shaped or box-shaped.
2. The pre-formed, shaped waterproofing membrane as claimed in claim 1, additionally comprising a protective coating layer (16) over said pressure-sensitive waterproofing adhesive layer (14).
3. The pre-formed, shaped waterproofing membrane as claimed in claims 1 or 2, packaged with a supporting structure (30), wherein said supporting structure has a three-dimensional contour (32) surrounded by a flat collar portion (34), and wherein said three-dimensional contour of said supporting structure corresponds with said three-dimensional contour of said shaped waterproofing membrane.
4. The pre-formed, shaped waterproofing membrane as claimed in claim 3, wherein said three-dimensional contour of said shaped waterproofing membrane has a dome shape and said three-dimensional contour of said supporting structure has a corresponding dome shape.
5. The pre-formed, shaped waterproofing membrane as claimed in claim 4, wherein said shaped waterproofing membrane has a protective coating layer (16) over said pressure-sensitive waterproofing adhesive layer (14).
6. The pre-formed, shaped waterproofing membrane as claimed in claim 1, wherein said carrier support sheet comprises a blend of low density
polyethylene and high density polyethylene and said pressure-sensitive waterproofing adhesive layer comprises styrene-isoprene-styrene.
7. The pre-formed, shaped waterproofing membrane as claimed in claim 1, wherein said three-dimensional contour has a diameter of 10 cm to 100 cm.
8. The pre-formed, shaped waterproofing membrane as claimed in claim 1, wherein said three-dimensional contour has a height of 10 cm to 100 cm.
9. A construction waterproofing kit comprising, in a package, a plurality of preformed, shaped waterproofing membranes as claimed in claim 1.
10. The construction waterproofing kit as claimed in claim 9, additionally comprising a plurality of supporting structures, wherein each supporting structure has a three-dimensional contour surrounded by a flat collar portion, and wherein said three-dimensional contour of said supporting structure corresponds with said three-dimensional contour of said shaped waterproofing membrane.
11. A method for making shaped waterproofing membranes as claimed in claim 1, comprising:
providing a membrane laminate comprising a polyolefin film carrier support sheet, a continuous non-bituminous synthetic pressure-sensitive waterproofing adhesive layer attached to said sheet and operative to bond with post cast concrete, and a protective coating attached to said adhesive layer and operative to protect said adhesive layer from dirt and operative to allow post cast concrete to bond with said adhesive layer; and
molding said membrane laminate to provide a three-dimensional contour surrounded entirely or partially by a flat collar portion, said pressure-sensitive waterproofing adhesive layer and said protective coating layer being operative after molding to provide a fully adhered waterproofing bond with freshly mixed concrete cast against said membrane and allowed to harden.
12. A method of waterproofing a building or civil construction surface having a
surface irregularity, comprising
applying to said building or civil construction surface over said surface irregularity a pre-formed, shaped waterproofing membrane (10) as claimed in claim 1, such that said pressure-sensitive waterproofing adhesive layer (14) is outwardly exposed to bond with post cast concrete.
13. The method as claimed in claim 12, comprising applying a supporting structure (30) over said surface irregularity prior to applying said shaped waterproofing membrane (10), then applying said shaped waterproofing membrane (10) over said supporting structure (30), wherein said supporting structure (30) has a three-dimensional contour surrounded by a flat, collar portion (34), and wherein said three-dimensional contour of said supporting structure corresponds with said three-dimensional contour of said shaped waterproofing membrane.
14. The method as claimed in claim 13, wherein said three-dimensional contour of said shaped waterproofing membrane (10) has a dome shape and said three-dimensional contour of said supporting structure (30) has a corresponding dome shape.
15. The method as claimed in claim 12, wherein said shaped waterproofing membrane (10) has a protective coating layer (16) over said pressure-sensitive waterproofing adhesive layer (14).
16. The method as claimed in claims 12, 13, 14 or 15, wherein said building or civil construction surface comprises a formwork and said surface irregularity comprises a tieback (40).
17. The method as claimed in claims 12, 13, 14 or 15, additionally comprising applying to said building or civil construction surface at least one sheet-form waterproofing membrane having a carrier support sheet with first and second opposed major faces and, disposed over said first major face, a pressure-
sensitive waterproofing adhesive layer operative to bond with post cast concrete, and overlapping and seaming said flat collar portion (13) of said shaped waterproofing membrane (10) with said at least one sheet-form waterproofing membrane.
18. The method as claimed in claim 17, wherein said sheet waterproofing membrane has a protective coating layer over said pressure-sensitive waterproofing adhesive layer.
19. The method as claimed in claim 12, wherein said carrier support sheet (12) is formed of synthetic polymer, metal, or combination thereof and said pressure-sensitive waterproofing adhesive layer comprises butyl rubber, polyisobutylene, polyisobutyl rubber, an acrylic or acrylate, a vinyl ether, styrene-isoprene-styrene, styrene-ethylene-butylene-styrene, styrene-butadiene-styrene, ethylene propylene diene, or a mixture thereof.
20. The method as claimed in claim 12, wherein said carrier support sheet (12) comprises low density polyethylene and said pressure-sensitive waterproofing adhesive layer (14) comprises styrene-isoprene-styrene.
21. The method as claimed in claim 17, wherein said at least one sheet-form waterproofing membrane carrier support sheet comprises high density polyethylene and said shaped waterproofing membrane carrier support sheet comprises a blend of low density polyethylene and high density polyethylene.
22. The method as claimed in claim 15, wherein said pressure-sensitive waterproofing adhesive layer (14) comprises styrene-isoprene-styrene and said protective coating layer (16) comprises an acrylate coating.
23. A waterproofed building or civil engineering structure provided by the method as claimed in claim 12.
|Indian Patent Application Number||5088/DELNP/2006|
|PG Journal Number||28/2013|
|Date of Filing||04-Sep-2006|
|Name of Patentee||W.R. GRACE & CO.-CONN|
|Applicant Address||7500 GRACE DRIVE, COLUMBIA, MARYLAND 21044, U.S.A.|
|PCT International Classification Number||B32B 3/00|
|PCT International Application Number||PCT/US2005/006704|
|PCT International Filing date||2005-03-02|