Sealing of Construction and Expansion Joints

dura.®joint flexband is a high performance waterproofing bandage composed of functionalized thermoplastic elastomers for a variety of applications.

The system for installation includes dura.®joint flexband, dura.®joint flexband adhesive (FDA compliant), dura.®joint HDPE strip, dura.®joint flexband solvent wipe, bond breaking tape and the appropriate sealant for various substrates.

Other auxiliary products where required include dura.®joint waterstop range and dura.®sheet joint former.

Uses

Waterproofing of expansion and construction joints. Applications in critical joint areas with high or frequent movement include: 

  • High movement joints (expansion) 
  • Construction/contraction joints 
  • Joints subject to chemical attack 
  • Repair of failed joints 
  • Repair/sealing to structural cracks 
  • Water retaining structure joint sealing
Advantages
  • Durable resilient seal 
  • Accepts multi-dimensional movement 
  • Can be applied to damp substrates (no free standing water) 
  • Can be used on a variety of substrates 
  • Can be used beneath asphalt 
  • Excellent application characteristics 
  • Can be used in contact with potable water 
  • Resistant to a wide range of chemicals 
  • Available in several widths 
  • Specification Compliance BS6920
Surface Preparation

The substrate must be structurally sound. Loose or unsound concrete must be removed and rectified where required. Surfaces must be entirely free of oil, grease, paint, corrosion deposits, dust, laitance or other surface deposits. The surface should be prepared by wire brushing, grit blasting, grinding, needle gun or high pressure water blasting to produce a fine exposed aggregate surface. 

Physical Properties

Test 

Method 

Result 

Burst pressure, max. 

Internal 

>5.0 bar 

Breaking load longitudinal 

DIN EN ISO 527-3 

14.0 N/mm2 

Breaking load lateral 

DIN EN ISO 527-3 

14.0 N/mm2 

Extension break longitudinal 

DIN EN ISO 527-3 

1000% 

Extension break lateral 

DIN EN ISO 527-3 

1000% 

Power absorption at 25% elasticity lateral 

DIN EN ISO 527-3 

5.6N/mm 

Power absorption at 50% elasticity lateral 

DIN EN ISO 527-3 

6.5N/mm 

Resistance to water pressure 

DIN EN 1928 (method B) 

>5.0 bar 

Resistance to tear longitudinal / lateral 

DIN EN 12310-2 

200N / 200N 

UV-Resistance, min. 

DIN EN ISO 4892-3 

6500 h 

Fire classification 

DIN EN 4102 

B2 

 

Temperature resistance 

-30ºC to +90ºC 

Shore A 

87 (approx.) 

Colour (may vary batch to batch) 

Grey 

1 mm lap bond @ 340ºC – Peel strength after 24 hours 

145N/25mm 

2 mm lap bond @ 370ºC – Peel strength after 24 hours 

240N/25mm 

Thickness (mm) 

*1 and 2 

Widths (mm) 

150, 200, 250, 300 & 350 

*1 mm available on special request 

Chemical Resistance

After 7 days submersion at 20ºC (+ = resistant) 

Hydrochloric acid 3% 

Internal 

Sulphuric acid 35% 

Internal 

Citric acid 100g/l 

Internal 

Lactic acid 5% 

Internal 

Potassium hydroxide 3%/ 20% 

Internal 

+ / + 

Sodium hypochlorite 0.3g/l 

Internal 

Salt water (20 g/l sea water salt 

Internal 

Priming

Priming for the dura.®joint flexband adhesive is not normally required. If the concrete is friable or very porous a primer may be required. Contact a.b.e.® Construction Chemicals for a site inspection and recommendations. See dura.®joint flexband adhesive product data sheet. 

Membrane Preparation

Cut the dura.®joint flexband membrane to the required length, then clean the faces to be bonded by wiping with dura.®joint flexband solvent wipe. Allow the surfaces to dry before bedding it into the dura.®joint flexband adhesive. If left for more than 8 hours, the membrane edges must be cleaned again and allowed to dry. 

Prepare dura.®joint flexband lap joints in advance by allowing a minimum of 100 mm overlap. The joints can only be made by using a hot air gun. To ensure intimate contact between bonded laps, place the dura.®joint flexband on a clean flat laminated timber board and apply pressure to the joint as it is being formed using a Leister roller to ensure maximum bond. All lap joints are to be carried out prior to installation. 

For welding lap joints the following equipment is required: Leister Triac AT – Hot air heat gun Nozzle: 40 mm Roller: 40 mm wide 30 mm diameter 1 mm dura.®joint flexband temperature setting of 340°C 2 mm dura.®joint flexband temperature setting of 370°C 

Mixing – Epoxy Adhesive

Refer to the dura.®joint flexband adhesive product datasheet. 

Application

Mask the area where the dura.®joint flexband adhesive is to be placed i.e. 25 mm on the concrete surface and extended 50 mm from the edge of the dura.®joint flexband membrane inwards. 

Where support below the dura.®joint flexband is required, position the dura.®joint HDPE strip to centrally straddle the expansion joint. 

A minimum thickness of 1 mm dura.®joint flexband adhesive applied to the concrete surface is required. After spreading the dura.®joint flexband adhesive, remove the innermost masking tape from both sides of the joint. Immediately place the dura.®joint flexband membrane, and using a hard roller, firmly roll the bandage to allow extrusion of the dura.®joint flexband adhesive beyond the edges of the membrane. Apply a second layer of dura.®joint flexband adhesive on top of the first layer to give a total dura.®joint flexband adhesive thickness of 2 mm and finish using a steel trowel. Remove the centrally placed masking tape from the dura.®joint flexband membrane. Remove the outer masking tape and featheredge the dura.®joint flexband adhesive by using a paint brush to chamfer any sharp edges/corners that may cut the membrane. Concrete surface profile and irregularities will influence the consumption rate of the dura.®joint flexband adhesive. See method statement for process.

Limitations
  • Do not apply to concrete substrates that are less than 28 days old. 
  • Do not apply to wet substrates (having free standing water). 
  • Do not apply in rain or wet conditions or at temperatures below 10°C. 
  • Do not fully immerse the joint system until full cure is achieved (7 days at 25°C, lower temperatures require a longer curing period). 
  • Do not expose the joint to traffic without the use of a suitable cover plate or protection.
Coverage

dura.®joint flexband as per roll length excluding overlaps dura.®joint flexband adhesive: Approximate theoretical quantities for estimation: 2 mm thick/m2 = 2 litres of product. 

 

Cleaning

Tools may be cleaned with abe® super brush cleaner immediately after use before the dura.®joint flexband adhesive has had time to cure, otherwise mechanical means will be required. 

Model Specification

dura.®joint flexband high performance waterproofing bandage system composed of functionalized thermoplastic elastomers.

For sealing of joints as per manufacturers requirements. 

Packaging
  • dura.®joint flexband is supplied in 20 metre rolls, see table for available widths.
  • dura.®joint HDPE strips: 3 mm thick, 50 & 75mm wide x 3m long
  • dura.®joint flexband adhesive: 2 litre kits
  • dura.®joint flexband solvent wipe: 5 litre container
  • abe® super brush cleaner: 5 litre container 
Handling & Storage

dura.®joint flexband Maximum 12 months when stored below 25°C under shade in a dry environment, protect against sunlight. If package has been opened apply the material within 2 months. 

Health & Safety

Product safety information required for safe use is not included. Before handling, read product and safety data sheets and container labels for safe use, physical and health hazard information. The safety data sheet is available from your local a.b.e.® Construction Chemicals sales representative.

Important Notice

This data sheet is issued as a guide to the use of the product(s) concerned. Whilst a.b.e.® Construction Chemicals endeavors to ensure that any advice, recommendation, specification or information is accurate and correct, the company cannot – because a.b.e.® has no direct or continuous control over where and how a.b.e.® products are applied – accept any liability either directly or indirectly arising from the use of a.b.e.® products, whether or not in accordance with any advice, specification, recommendation, or information given by the company.

Further Information

Where other products are to be used in conjunction with this material, the relevant technical data sheets should be consulted to determine total requirements. a.b.e.® Construction Chemicals has a wealth of technical and practical experience built up over years in the company’s pursuit of excellence in building and construction technology.

Illustrations

Dura-joint-flexband-illustrationdura-joint-flexband-illustration2