Sikadur®-31+
Low-VOC epoxy adhesive for structural bonding and concrete repair
Sikadur®-31+ is a 2-part, low-VOC, moisture-tolerant epoxy structural adhesive which bonds to many construction materials. It is also used for structural concrete repairs, joint filling, and crack sealing. It can be used in both do-it-yourself (DIY) applications and professional applications.
- Easy to mix and apply
- Very low VOC (GEV Emicode EC1PLUS)
- Very good adhesion to many construction materials
- Very good initial and ultimate mechanical strength
- Suitable for structural concrete repair, class R4 according to EN 1504-3:2005 (Structural and non-structural repair)
- Good adhesion to dry and mat damp concrete
- Thixotropic: non-sag in vertical and overhead applications
- No primer required
- Good resistance to abrasion
- Good resistance to specific chemicals
- Differently coloured components for mixing control
- Impermeable to most liquids and water vapour
- Hardens without shrinkage
- Application up to 30 mm thickness in one layer
- Temperature application range +10 °C to +30 °C
Areas of Application
The Product is used as an adhesive for:- Structural concrete repair (Principle 3, Method 3.1 of EN 1504-9). Repair of spalling and damaged concrete in buildings, bridges, infrastructure and superstructure works
- Structural strengthening (Principle 4, Method 4.3 of EN 1504-9). Bonding plate reinforcement
- Structural strengthening (Principle 4, Method 4.4 of EN 1504-9). Increasing the bearing capacity of the concrete structure by adding mortar
- Concrete
- Natural stone
- Ceramics
- Fibre cement
- Mortar
- Brick masonry
- Brick slips
- Steel
- Iron
- Wood
- Structural concrete elements such as beams, columns, and walls
- Non-structural concrete elements
- Small patches and edges
- Joint arrises
- Crack arrises
- Non-structural static cracks
- Holes
- Voids
Advantages
- Easy to mix and apply
- Very low VOC (GEV Emicode EC1PLUS)
- Very good adhesion to many construction materials
- Very good initial and ultimate mechanical strength
- Suitable for structural concrete repair, class R4 according to EN 1504-3:2005 (Structural and non-structural repair)
- Good adhesion to dry and mat damp concrete
- Thixotropic: non-sag in vertical and overhead applications
- No primer required
- Good resistance to abrasion
- Good resistance to specific chemicals
- Differently coloured components for mixing control
- Impermeable to most liquids and water vapour
- Hardens without shrinkage
- Application up to 30 mm thickness in one layer
- Temperature application range +10 °C to +30 °C
Packaging
1.2 kg (A+B) container | 8 × 1.2 kg carton box 32 boxes per pallet - 256 pieces |
6 kg (A+B) container | 96 containers per pallet |
20 kg (A) container | 22 containers (A) per pallet |
10 kg (B) container | 44 containers (B) per pallet |
Refer to the current price list for available packaging variations.
Color
Part A | White |
Part B | Dark grey |
Part A+B mixed | Concrete grey |
Product Details
SUSTAINABILITY
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Contributes towards satisfying Materials and Resources (MR) Credit: Building product disclosure and optimization — Environmental Product Declarations under LEED® v4
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Contributes towards satisfying Materials and Resources (MR) Credit: Building Product Disclosure and Optimization — Material Ingredients under LEED® v4
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Contributes towards satisfying Indoor Environmental Quality (EQ) Credit: Low-Emitting Materials under LEED® v4
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Environmental Product Declaration (EPD) in accordance with EN 15804. EPD independently verified by Institut für Bauen und Umwelt e.V. (IBU)
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VOC emission classification GEV Emicode EC1plus
APPROVALS / CERTIFICATES
CE marking and declaration of performance based on EN 1504-3:2005 Products and systems for the protection and repair of concrete structures — Structural and non-structural repair
CE marking and declaration of performance based on EN 1504-4:2004 Products and systems for the protection and repair of concrete structures — Structural bonding
Product declaration
Complies with the general requirements of EN 1504-3: Class R4
Complies with the general requirements of EN 1504-4: Structural bonding for bonded plate reinforcement and bonded mortar or concrete
Composition
Epoxy resin and selected fillers
Shelf life
24 months from date of production
Storage conditions
The product must be stored in original, unopened and undamaged sealed packaging in dry conditions at temperatures between +5 °C and +30 °C. Always refer to packaging.
Refer to the current Safety Data Sheet for information on safe handling and storage.
Density
Mixed resin (2.00 ± 0.1) kg/l
Density value at +23 °C.
Volatile organic compound (VOC) content
Compliant with VOC emission classification GEV-Emicode EC1PLUS
Compressive strength
Class R4 | (EN 1504-3) |
~75 MPa | (EN 12190) |
Curing time | +10 °C | +23 °C | +30 °C |
1 day | - | 50 MPa | 50 MPa |
3 days | 50 MPa | 65 MPa | 70 MPa |
7 days | 70 MPa | 75 MPa | 78 MPa |
Tensile strength
Curing time | +10 °C | +23 °C |
1 day | - | 8.5 MPa |
3 days | 6 MPa | 16 MPa |
7 days | 16 MPa | 20 MPa |
Shear strength
16 MPa | (EN 12615) |
50° | 35 MPa |
60° | 30 MPa |
70° | 25 MPa |
Tensile adhesion strength
Pass | (EN 12636) |
Curing Time | Substrate | Curing Temperature | Adhesion strength |
7 days | Concrete dry | +23 °C | > 5 MPa * |
7 days | Concrete mat damp | +23 °C | > 5 MPa * |
7 days | Steel | +23 °C | > 20 MPa |
* 100% concrete failure
Shear adhesion strength
50° | ≥ 60 MPa |
60° | ≥ 70 MPa |
70° | ≥ 80 MPa |
Shrinkage
~0.01 % | (EN 12617-1) |
3.0 MPa (Restrained shrinkage / expansion) | (EN 12617-4) |
Coefficient of thermal expansion
4.8 × 10-5 (±0.2 × 10-5) 1/K | (EN 1770) |
Glass transition temperature
50 °C | (EN 12614) |
Thermal compatibility
Freeze and thaw | 3.00 MPa |
Durability | Pass |
Chemical resistance
Resistant to many chemicals. Contact Sika Technical Services for additional information.
Resistance to moisture
Sensitivity to water | Pass |
Reaction to fire
Class C-s1, d0 Class Bfl-s1 | (EN 13501-1) |
Application
Mixing ratio
Part A : Part B = 2 : 1 by weight or volume
Layer thickness
30 mm max.
For non-structural adhesive or other applications, if layer thickness’s of >30 mm are required, apply in successive 30 mm layers or once the previous layer has hardened. The surface of the freshly applied intermediate layers should be scratched to form a key for subsequent layers. If layer application is to be longer than 2 days, the wet applied adhesive must be blinded to excess with quartz sand immediately after application
Sag flow
Non-sag up to 20 mm thickness on vertical surfaces | (EN 1799) |
Material temperature
Maximum | +30 °C |
Minimum | +10 °C |
Ambient air temperature
Maximum | +30 °C |
Minimum | +10 °C |
Dew point
Beware of condensation.
Steel substrate temperature during application must be at least +3 °C above dew point.
Substrate temperature
Maximum | +30 °C |
Minimum | +10 °C |
Substrate moisture content
Substrates must be dry or matt damp (no standing water).
Brush the adhesive well into the substrate if matt damp.
Pot Life
Temperature | Pot Life |
+23 °C | ~60 min |
+30 °C | ~45 min |
Open Time
Temperature | Open Time |
+23 °C | ~75 min |
+30 °C | ~45 min |
Consumption
2.0 kg/m2 per mm of thickness.
Note: Consumption data is theoretical and does not allow for any additional material due to surface porosity, surface profile, variations in level, wastage or any other variations. Apply product to a test area to calculate the exact consumption for the specific substrate conditions and proposed application equipment.
SUBSTRATE QUALITY
CONCRETE, MASONRY, MORTAR, STONE
Concrete and mortar must be at least 28 days old.
Substrates must be sound, clean, dry or matt damp but free of standing water. Substrates must be free of contaminants such as ice, dirt, oil, grease, coatings, laitance, efflorescence, surface treatments and loose friable material.
STEEL
Surfaces must be sound, clean, dry and free of contaminants such as dirt, oil, grease, coatings and loose friable material.
WOOD
Surfaces must be sound, clean, dry and free of contaminants such as dirt, oil, grease, coatings and loose friable material.
SUBSTRATE PREPARATION
IMPORTANT
Reduced adhesion due to surface contamination
Surface contaminants such as dust and loose material, including the contaminants generated during substrate preparation, can reduce the Product's performance.
- Before applying the Product, clean thoroughly all substrate surfaces using vacuum or dust removal equipment.
CONCRETE, MASONRY, MORTAR OR STONE
Suitable techniques for substrate preparation include the following:
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Abrasive blast cleaning
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Needle gunning
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Light scabbling
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Bush hammering
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Grinding
- Prepare the substrate mechanically using a suitable technique.
The substrate has an open-textured, gripping surface profile.
STEEL
Suitable techniques for substrate preparation include the following:
-
Abrasive blast cleaning
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Rotating wire brush
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Grinding
- Prepare the substrate mechanically using a suitable technique.
The substrate has a bright metal finish with a surface profile to satisfy the necessary tensile adhesion strength requirement.
WOOD
- Prepare the substrate by planing, sanding or using other suitable equipment.
MIXING
IMPORTANT
Poor workability and unfavourable handling time due to wrong mixing
- When using multiple units during application, do not mix the following unit until the previous unit has been used.
PRE-BATCHED UNITS
- IMPORTANT Mix full units only. Prior to mixing all parts, mix part A (resin) briefly using a mixing spindle attached to a slow-speed electric mixer (max. 300 rpm).
- Add part A to part B (hardener) and mix parts A+B continuously for at least 3 minutes until a uniformly coloured, smooth consistency mix has been achieved.
- IMPORTANT Do not overmix. To ensure thorough mixing, pour materials into a clean container and mix again for approximately 1 minute. Mixing time for A+B = 4 minutes.
APPLICATION
IMPORTANT
Damage due to unsupported heavy components applied vertically or overhead
Full adhesion is not achieved before the Product has fully hardened. Hardening depends on ambient temperatures. Unsupported heavy components might fall down when not supported.
- Provide temporary support for heavy components until the Product has fully hardened.
BONDING
Preconditions: Prior to application confirm dew point conditions before and during application.
- IMPORTANT On damp prepared concrete substrates, always apply the Product by brush and work the Product well into the substrate. Apply the mixed adhesive to the prepared surfaces with a spatula, trowel, notched trowel or by gloved hand.
- For optimum adhesion apply the adhesive to both surfaces that require bonding.
- For heavy components positioned vertically or overhead, provide temporary support until the Product has fully hardened.
REPAIR
Preconditions: Prior to application confirm dew point conditions before and during application.
- Place temporary formwork as required.
- IMPORTANT On damp prepared concrete substrates, always apply by brush and work the Product well into the substrate. Apply the mixed adhesive to the prepared surfaces with a spatula, trowel or by gloved hand.
For repairs greater than 30 mm deep the Product must be applied in layers.
- Roughen the surface of the freshly applied intermediate layer by scratching it to enable better adhesion of the subsequent layer.
- Apply subsequent layers once the previous layer has hardened.
- If the time between layers is going to be more than 2 days, blind the wet adhesive to excess with quartz sand immediately after application.
JOINT FILLING AND CRACK SEALING
- Apply the mixed adhesive to the prepared surfaces with a spatula or trowel.
CLEANING OF EQUIPMENT
Clean all tools and application equipment with Sika® Colma Cleaner immediately after use. Hardened material can only be removed mechanically.