Cellflex: Bitumen Impregnated Fibreboard Expansion Joint Filler

Product Overview

Cellflex is a compressible, non-extruding, bitumen impregnated fibreboard expansion joint filler supplied in sheet form for use in concrete construction. It is manufactured by Fosroc and supplied by Parchem for use in forming and filling expansion joints in in-situ concrete applications.

Key Features and Advantages

Cellflex offers several distinctive characteristics that make it suitable for expansion joint applications:

• Easy to handle, cut and tamp - The product can be readily cut and shaped on-site without specialized equipment
• Resilient - Maintains its structural integrity under compression and recovers after compression cycles
• Non-extruding - Will not extrude under compression, a critical advantage for preventing material displacement from joints
• Compressible sheet form - Supplied as flexible sheets that accommodate joint movement

Material Composition and Properties

Physical Characteristics

The material composition and performance specifications of Cellflex are as follows:

Property	Specification
Form	Compressible sheet
Bitumen Content	35% by weight
Density	377 kg/m³
Compression Strength	2590 kPa
Recovery Performance	Greater than 70% after compression
Water Absorption	Less than 15%

Material Composition

Cellflex is composed of bitumen impregnated fibreboard, which combines bitumen (35% by weight) with fibreboard material to create a compressible, resilient filler suitable for dynamic joint applications.

Standards Compliance

Cellflex complies with ASTM D1751 - Compression & Recovery Test, ensuring that the product meets established international standards for expansion joint fillers.

Applications

Cellflex is suitable for forming structural expansion and separation joints in a wide variety of concrete construction applications:

• Concrete pavements and floors - Both trafficked and non-trafficked surfaces
• Roads, ramps and runways - Transportation infrastructure requiring controlled joint movement
• Pedestrian areas - Specialized concrete surfaces for walking areas
• Concrete retaining walls and bridges - Structural systems subject to significant loads and movement
• Concrete basement structures and subways - Underground applications requiring durability and water resistance
• Joints between in-situ and pre-cast concrete construction - Connection points in mixed construction methods

Installation Methods

In-Situ Concrete Applications

When used to form expansion joints in in-situ concrete, Cellflex shall be placed against the shuttering on the concreting side before the pour begins. This positioning ensures proper integration with the concrete as it cures.

Retrofit Applications

Cellflex may be bonded to existing concrete slabs or previous pours using a suitable adhesive, providing flexibility for retrofit or secondary construction phases where joints need to be formed after initial concrete placement.

Joint Sealant Compatibility

Critical Limitation

Cellflex must only be used with bitumen-based joint sealants. This is a fundamental compatibility requirement that must be strictly observed.

Incompatibility with Elastomeric Sealants

Cellflex must not be used in joints where any subsequent joint sealant is other than bitumen based. The mobile fractions of the bitumen in Cellflex are likely to degrade elastomeric sealants through chemical degradation, compromising the sealant's integrity and performance. Elastomeric sealants should never be used as a sealing material over Cellflex.

Supply Specifications

Cellflex is supplied in a range of sheet and strip sizes to accommodate various joint width requirements:

Sheet Sizes

• 2.20m × 1220mm × 12mm
• 2.44m × 1200mm × 9.5mm

Strip Sizes (All 2.44m length × 9.5mm thickness)

• 60mm, 75mm, 100mm, 125mm, 150mm, 200mm, 300mm widths

Note: Board size tolerance is +/- 3%

Storage Requirements

Critical Storage Conditions

Cellflex must be stored under cover in dry conditions. Proper storage is essential due to the organic material composition of the product.

Spontaneous Combustion Risk

There is a very slight risk of spontaneous combustion if stored long-term in wet conditions due to the organic material nature of the product. Storage in wet environments should be strictly avoided. Under cover, dry storage conditions mitigate this risk effectively.

Important Documentation and Safety

Before using Cellflex, users must carefully review:

• Safety Data Sheet (SDS) - Available from the Fosroc website
• Technical Data Sheet (TDS) - Contains application and performance specifications
• Application or performance data may change from time to time, necessitating review of current documentation

In emergency situations, contact any Poisons Information Centre (phone 13 11 26 within Australia) or a doctor for advice.

Product Liability and Disclaimer

Parchem Construction Supplies is responsible for supply and liability of Cellflex products. The product responsibility is subject to standard terms and conditions of sale, and Parchem does not accept liability for losses suffered through use or application of the product, whether or not in accordance with provided advice or specifications.

References

• [1] Fosroc_Cellflex_TDS.pdf