Xypex® Modified.
Waterproofing concrete
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Xypex® Modified
Concrete Waterproofing by Crystallization
DESCRIPTION
Concrete Waterproofing
Xypex is a unique chemical treatment for the waterproofing, protection and repair of concrete. XYPEX MODIFIED can be applied as a second coat to reinforce Xypex Concentrate, or applied by itself to damp-proof the exterior of foundation walls. Applied as a second coat, Xypex Modified chemically reinforces Xypex Concentrate where two coats are required and produces a harder finish. Where damp-proofing is required, a single coat of Modified may be used as an alternative to a spray/tar emulsion. Xypex prevents the penetration of water and other liquids from any direction by causing a catalytic reaction that produces a non-soluble crystalline formation within the pores and capillary tracts of concrete and cement-based materials.
Xypex Modified is recommended as a single coat for the damp-proofing of foundations or as a second coat with Xypex Concentrate for the following applications:
PACKAGING
Xypex Modified, concrete waterproofing, is available in 9.1 kg and 27.2 kg pails and 22.7 kg bags.
STORAGE
Xypex products must be stored dry at a minimum temperature of 45ºF (7ºC). Shelf life is one year when stored under proper conditions.
COVERAGE
For normal surface conditions, the coverage rate for each coat is 6 - 7.2 sq. ft. per lb. (1.25 - 1.5 lb. per sq. yd. or 0.65 - 0.8 kg/m2).
TEST RESULTS DEL IMPERMEABILIZANTE HOMIRGÓN
Concrete waterproofing. Permeability
U.S. Army Corps of Engineers (USACE) CRD C48-73, “Permeability of Concrete”, Pacific Testing Labs,Seattle, USA
Two in. (51 mm) thick, 2000 psi (13.8 MPa) Xypex-treated concrete samples were pressure tested up to a 405 ft. (124 m) water head (175 psi/1.2 MPa), the limit of the testing apparatus. While untreated samples showed marked leakage, the Xypex-treated samples (as a result of the crystallization process) became totally sealed and exhibited no measurable leakage.
DIN 1048, “Water Impermeability of Concrete”, Bautest – Corporation for Research & Testing of Building Materials, Augsburg, Germany
Twenty cm thick Xypex-treated concrete samples were pressure tested up to 7 bars (230 ft./70 m water head) for 24 hours to determine water impermeability. While the reference specimens measured water penetration up to a depth of 92 mm, Xypex-treated samples measured water penetration of zero to an average of 4 mm.
ÖNORM B 3303, “Water Permeability of Concrete”, Technologisches Gerwerbemuseum, Federal Higher Technical Education & Research Institute,
Vienna, Austria
Xypex-treated concrete samples were pressure tested to a maximum 7 bars (230 ft./70 m water head) for 10 days. Test revealed that while 25 ml of water had penetrated the untreated concrete samples, zero ml had penetrated the Xypex-treated samples. Test specimens were then broken and showed water penetration to a depth of 15 mm on untreated samples but no measurable water penetration on the Xypex-treated samples
CSN 1209/1321, “Impermeability and Resistance to Pressurized Water”, Institute of Civil Engineering, Technology and Testing, Bratislava, Slovak Republic
Xypex-treated and untreated concrete samples were
exposed to 1.2 MPa of pressure to determine water permeability. Results showed the Xypex-treated samples provided effective protection against hydrostatic water pressure. Treated and untreated samples were also subjected to contact with silage juices and various petroleum products (e.g. diesel oil, transformer oil, gasoline) at 14 kPa for 28 days. The Xypex-treated samples significantly reduced the penetration of these solutions
Waterproofing concrete. Chemical resistance
RECOMMENDED FOR
Reservoirs
Sewage and Water Treatment Plants
Secondary Containment Structures
Tunnels and Subway Systems
Underground Vaults
Foundations
Parking Structures
Swimming Pools
ADVANTAGES
Resists extreme hydrostatic pressure
Becomes an integral part of the substrate
Allows concrete to breathe
Resistant to aggressive chemicals
Non-toxic
Does not require dry weather or a dry surface
Cannot puncture, tear or come apart at the seams
No costly surface priming or leveling prior to application
Does not require sealing, lapping and finishing of seams at corners, edges or between membranes
Can be applied to the positive or the negative side of the concrete surface
Does not require protection during backfilling or during placement of steel, wire mesh or other materials
Less costly to apply than most other methods
Not subject to deterioration
Permanent
ASTM C 267-77, “Chemical Resistance to Mortars”, Pacific Testing Labs, Seattle, USA
Xypex-treated cylinders and untreated cylinders were exposed to hydrochloric acid, caustic soda, toluene, mineral oil, ethelyne glycol, pool chlorine and brake fluid and other chemicals. Results indicated that chemical exposure did not have any detrimental effects on the Xypex coating. Tests following chemical exposure measured an average 17% higher compressive strength in the Xypex-treated specimens over the untreated control samples.
IWATE University Technical Report, “Resistance to Acid Attack”, Tokyo, Japan
Xypex-treated mortar and untreated mortar were measured for acid resistance after exposure to a 5% H2SO4 solution for 100 days. Xypex suppressed concrete erosion to 1/8 of the reference samples.
Waterproofing concrete. Freeze/Thaw durability
ASTM C 672, “Standard Test Method for Scaling
Resistance of Concrete Surfaces Exposed to De-Icing Chemicals”, Twin City Testing Lab, St. Paul, USA
Xypex-treated samples restricted chloride ion concentration to below the level necessary to promote electrolytic corrosion of reinforcing steel. Visual examination of untreated panels after 50 freeze/thaw cycles showed a marked increase in surface deterioration compared to Xypex-treated samples.
Waterproofing concrete. Potable water exposure
NSF 61, “Drinking Water System Component-Health Effects”, NSF International, Ann Arbor, USA
Exposure testing of potable water in contact with Xypex-treated samples indicated no harmful effects.
Waterproofing concrete. Radiation resistance
U.S.A. Standard No. N69 ,“Protective Coatings for the Nuclear Industry”, Pacific Testing Labs, Seattle, USA
After exposure to 5.76 x 104 rads of gamma radiation, the Xypex treatment revealed no ill effects or damages.
APPLICATION PROCEDURES
1. Waterproofing concrete. Surface preparation
Concrete surfaces to be treated must be clean and free of laitance, dirt, film, paint, coating or other foreign matter. Surfaces must also have an open capillary system to provide “tooth and suction” for the Xypex treatment. If surface is too smooth (e.g. where steel forms are used) or covered with excess form oil or other foreign matter, the concrete should be lightly sandblasted, waterblasted, or etched with muriatic (HCL) acid.
2. Waterproofing concrete . Structural repair
Rout out cracks, faulty construction joints and other structural defects to a depth of 1.5 in. (37 mm) and a width of 1 in. (25 mm). Apply a brush coat of Xypex Concentrate as described in steps 5 & 6 and allow to dry for 10 minutes. Fill cavity by tightly
compressing Dry-Pac into the groove with pneumatic packing tool or with hammer and wood block. Dry-Pac is prepared by mixing six parts Xypex Concentrate powder with one part water to a dry, lumpy consistency.
Note:
i. Against a direct flow of water (leakage) or where there is excess moisture due to seepage, use Xypex Patch’n Plug then Xypex Dry-Pac followed by a brush coat of Xypex Concentrate. (Refer to Xypex Specifications and Applications Manual for full details.)
ii. For expansion joints or chronic moving cracks, flexible materials such as expansion joint sealants should be used.
3. Waterproofing concrete. Wetting concrete
Xypex requires a saturated substrate and a damp surface. Concrete surfaces must be thoroughly saturated with clean water prior to the application so as to aid the proper curing of the treatment and to ensure the growth of the crystalline formation deep within the pores of the concrete. Remove excess surface water before the application. If concrete surface dries out before application, it must be re-wetted.
4. Waterproofing concrete. Mixing for slurry coat
Mix Xypex powder with clean water to a creamy consistency in the following
proportions:
For Brush Application
1.25- 1.5 lb./sq. yd. (0.65 - 0.8 kg/m2)
5 parts powder to 2 parts water
2.0lb./sq. yd. (1.0 kg/m2)
3 parts powder to 1 part water
For Spray Application
1.25- 1.5 lb./sq. yd. (0.65 - 0.8 kg/m2)
5 parts powder to 3 parts water (ratio may vary with equipment type)
Do not mix more Xypex material than can be applied in 20 minutes. Do not add water once mix starts to harden. Protect hands with rubber gloves
5. Waterproofing concrete. Applying Xypex
Apply Xypex with a semi-stiff nylon bristle brush, push broom (for large horizontal surfaces) or specialized spray equipment. The coating must be uniformly applied and should be just under 1/16 in. (1.25 mm). When a second coat (Xypex Concentrate or Xypex Modified) is required, it should be applied after the first coat has reached an initial set but while it is still “green” (less than 48 hours). Light pre-watering between coats may be required due to drying. The Xypex treatment must not be applied under rainy conditions or when ambient temperature is below 40ºF (4ºC). For recommended equipment, contact Xypex Chemical Corporation or your nearest Xypex distributor.
6. Waterproofing concrete. Curing
A misty fog spray of clean water must be used for curing the Xypex treatment. Curing should begin as soon as the Xypex has set to the point where it will not be damaged by a fine spray of water. Under normal conditions, it is sufficient to spray Xypex-treated surfaces three times per day for two to three days. In hot or arid climates, spraying may be required more frequently. During the
curing period, the coating must be protected from rainfall, frost, wind, the puddling of water and temperatures
below 36ºF (2ºC) for a period of not less than 48 hours after
application. If plastic sheeting is used as protection, it must be raised off the Xypex to allow the coating to breathe. Xypex Gamma Cure may be used in lieu of water curing for certain applications (consult with Xypex Chemical Corporation or your nearest Xypex distributor).
Note: For concrete structures that hold liquids (e.g.
reservoirs, swimming pools, tanks, etc.), Xypex should be cured for three days and allowed to set for 12 days before filling the structure with liquid.
TECHNICAL SERVICES
For more instructions, alternative application methods, or information concerning the compatibility of the Xypex treatment with other products or technologies, contact the Technical Services Department of Xypex Chemical Corporation or your local Xypex representative.
SAFE HANDLING INFORMATION
Xypex is alkaline. As a cementitious powder or mixture, Xypex may cause significant skin and eye irritation. Directions for treating these problems are clearly detailed on all Xypex pails and packaging. The Manufacturer also maintains comprehensive and up-to-date Material Safety Data Sheets on all its products. Each sheet contains health and safety information for the protection of workers and customers. The Manufacturer recommends you contact Xypex Chemical Corporation or your local Xypex representative to obtain copies of Material Safety Data Sheets prior to product storage or use.
WARRANTY
The Manufacturer warrants that the products manufactured by it shall be free from material defects and will be consistent with its normal high quality. Should any of the products be proven defective, the liability to the Manufacturer shall be limited to replacement of the product ex factory. The Manufacturer makes no warranty as to merchantability or fitness for a particular purpose and this warranty is in lieu of all other warranties expressed or implied. The user shall determine the suitability of the product for his intended use and assume all risks and liability in connection therewith.
