Conbextra Deep Pour - Technical Details, Specifications, Features, and Entities

Product Overview

Conbextra Deep Pour is a flowable, precision, cementitious grout specifically engineered for large volume and deep pour applications. It is designed for grouting gap applications ranging from 20mm to 500mm in thickness, making it an ideal solution for applications where standard grout products are insufficient.

The product is supplied as a free-flowing, ready-to-use dry powder that requires mixing with clean water to achieve the desired consistency. It is available in 20-kilogramme bags or 1000-kilogramme bulk bags (made to order), offering flexibility for both small and large-scale grouting operations.

Key Advantages

Conbextra Deep Pour offers several distinctive advantages that set it apart from standard grout products:

• Dual Shrinkage Compensation: Features a non-metallic, dual expansion system that compensates for shrinkage in both plastic (Class A) and hardened states (Class C)
• Non-Shrink Properties: Certified non-shrink according to ASTM C1107:2020 standard
• Excellent Flow Characteristics: Demonstrates excellent initial flow and flow retention capabilities
• Versatile Application Methods: Suitable for both pumping and pouring into position
• High Durability: Combines high ultimate strength with low permeability to ensure long-term durability of hardened grout
• Hydrogen-Free Gaseous Expansion: Utilizes a safe expansion mechanism without hydrogen gas production
• Chloride-Free Formulation: Contains no chlorides, making it suitable for use on reinforced concrete structures
• RCS Hazard-Free: Classified as not hazardous for Respirable Crystalline Silica (RCS), containing less than 0.1% RCS

Chemical Composition and Description

Conbextra Deep Pour is a blend of Portland cements, graded fillers, and chemical additives that work synergistically to provide controlled expansion in both plastic and hardened states. The formulation is engineered with:

• Filler grading that minimizes segregation and bleeding across a wide range of application consistencies
• Low water requirement that ensures high early strength development and long-term durability
• Maximum filler aggregate size of 5mm, which is compatible with standard pumping equipment

Technical Specifications and Properties

Dimension Specifications

Property	Specification
Minimum Thickness	20mm
Maximum Thickness	500mm

Compressive Strength

Conbextra Deep Pour exhibits varying compressive strength values depending on consistency level and curing time, measured according to AS 1478.2:2005 standard using cube samples:

Consistency	Water Addition (L/20kg)	1 Day (MPa)	7 Days (MPa)	28 Days (MPa)
Plastic	2.4 - 2.6	10	45	65
Flowable	2.6 - 2.8	5	42	60

Flexural Strength (Modulus of Rupture)

Measurement Period	Strength Value
7 Days	5.0 MPa
28 Days	7.5 MPa

Indirect Tensile Strength

Measurement Period	Strength Value
7 Days	2.5 MPa
28 Days	4.0 MPa

Setting Time

Conbextra Deep Pour demonstrates the following setting times according to AS 1012.18:1996 standard:

Setting Phase	Duration
Initial Set	6.5 hours
Final Set	9.0 hours

When tested to ASTM C953:2017 specification:

• Initial Set: 390 minutes (6.5 hours)
• Final Set: 440 minutes (7.33 hours)

Physical Properties

Property	Value
Fresh Wet Density	2200 kg/m³ (depending on consistency used)
Flow Characteristics	500mm (measured using Flow Trough test method)
Alkali Reactive Particles	Non-reactive (per Rapid Mortar Bar Test RTA T363)

ASTM C1107:2020 Compliance Results

Test Method	Standard	Result
Flow Consistency	ASTM C939:2016a	>145%
Setting Time	ASTM C953:2017	Initial: 390 mins; Final: 440 mins
Change in Height at Early Age	ASTM C827:2016	+0.29%
Height Change - Moist Cure	ASTM C1090:2015	+0.3% (at 1, 3, 14, and 28 days)
Compressive Strength	ASTM C109:2020b	1 day: 13.8 N/mm²; 3 days: 39.4 N/mm²; 7 days: 51.2 N/mm²; 28 days: 63.8 N/mm²

Standards Compliance

Conbextra Deep Pour complies with multiple international and Australian standards:

• AS 1478.2-2005: Appendix E for Early Volume Change testing
• AS 1478.2-2005: Table 4.1.2.2 for Consistency classification
• ASTM C1107:2020: Non-shrink cementitious grout specification
• Rapid Mortar Bar Test (RTA T363): For alkali-silica reactivity assessment
• SAA MP20.3-1977: Class A & Class C designation

Mixing Specifications

Water Addition Requirements

The specific water content varies based on the required consistency:

Required Consistency	Litres of Water per 20kg Bag	Yield (Litres of Mixed Material)
Plastic	2.4 - 2.6	10.0
Flowable	2.6 - 2.8	10.0

Mixing Equipment and Procedure

• Mixer Type: Forced-action mixer is essential
• Mixing Speed: 400-500 rpm at slow speed
• Mixing Duration: 3 to 5 minutes continuously
• Equipment Specification: 120/140mm helical mixing paddle fitted to heavy-duty 1600W mixer
• Mixing Method: Water is placed in the mixing bucket first, then powder is slowly added while continuously mixing
• Consistency Requirement: A smooth, even consistency must be obtained before placement

Mixing Larger Volumes

For larger quantities beyond 50kg:

• Equipment Required: High shear vane mixer
• Holding Capacity: May require a grout holding tank with gentle agitation capability to maintain fluidity during continuous grouting operations
• Precaution: Do not use colloidal impeller mixers

Application Characteristics

Grout Consistency Options

Conbextra Deep Pour can be mixed to achieve different consistencies:

• Plastic Consistency: Water addition of 2.4-2.6 litres per 20kg bag, producing compressive strengths of 10 MPa (1 day), 45 MPa (7 days), and 65 MPa (28 days)
• Flowable Consistency: Water addition of 2.6-2.8 litres per 20kg bag, producing compressive strengths of 5 MPa (1 day), 42 MPa (7 days), and 60 MPa (28 days)

Flow Properties

Flow distances vary based on gap depth and grout head applied:

Gap Depth (mm)	Flowable @ 100mm Head (mm)	Flowable @ 250mm Head (mm)
30	1500	3000
40	2200	3000+
50	3000	3000+

Placement Method

• Grout must be placed within 15 minutes of mixing to gain full benefit of the expansion process
• Continuous grout flow is essential during placement
• Grout should be poured from one side of the void only to eliminate air entrapment and surplus pre-soaking water
• Pouring should traverse the shortest distance to achieve a continuous grout front

Temperature Considerations

Low Temperature Working (5°C or below):

• Use warm water (30-40°C) to accelerate strength development
• For ambient temperatures below 10°C, use flowable consistency
• Maintain formwork in place for at least 36 hours
• Follow normal winter working precautions for cementitious materials

High Temperature Working (above 35°C):

• Store mixed grout in shade
• Use cool water (below 20°C) for mixing
• Long narrow grouting sections should be avoided where possible
• Arrange pours to achieve a length:minimum thickness ratio of not more than 20:1

Pre-Application Preparation Requirements

Foundation Surface Preparation

• Must be free from oil, grease, and any loosely adherent material
• If concrete surface is defective or has laitance, it must be cut back to sound base
• Surfaces should be abraded or roughened by mechanical means (needle gun, grit blasting, or grinding)
• Bolt holes and fixing pockets must be blown clean of dirt and debris

Base Plate Requirements

• Must be clean and free from oil, grease, or scale
• Air pressure relief holes should be provided to allow venting of isolated high spots

Pre-Soaking Process

• Pre-soaking the formed grouting area with clean water improves adhesion and flow
• The area should be filled with clean water for a minimum of 2 hours before grouting
• Immediately before grouting, any free water should be removed by draining or vacuum
• Particular care should be taken to blow out bolt holes and pockets

Formwork Requirements

• Minimum gap for pouring Conbextra Deep Pour is 25mm
• Formwork must be constructed to be leakproof as the product is free-flowing
• Leakproofing can be achieved using foam rubber strip or construction silicone sealant beneath formwork and between joints
• Unrestrained surface area should be kept to a minimum
• Gap width between perimeter formwork and plate edge should not exceed 150mm on pouring side and 50mm on opposite side
• No gap at flank sides is advisable

Curing Requirements

Upon completion of the grouting operation, exposed areas must be thoroughly cured using one or more of the following methods:

• Fosroc Concure A99 curing membrane application
• Continuous water application to maintain moisture
• Wet hessian or polyethylene wrapping to prevent premature drying
• Curing compound application to the exposed edge of grout after formwork removal

Pumping and Large Volume Applications

Where large volumes must be placed:

• Pump Type: Heavy duty diaphragm pump is recommended; screw feed and piston pumps may also be suitable
• Maximum Aggregate Size: 5.0mm for pumping operations
• Pump Capability: Ensure the selected pump is capable of handling the 5.0mm aggregate size

Storage and Shelf Life

• Shelf Life: 18 months from date of manufacture when kept in original, unopened bags
• Storage Conditions: Store in dry conditions in original, unopened packaging
• High Temperature/Humidity Impact: Shelf life may be reduced if stored at high temperatures and/or high humidity conditions
• Use Limitations: Do not use if lumps are present in the product or if loss of workability is experienced (requiring additional water to be added)

Supply Formats

Product Description	Product Code
Conbextra Deep Pour 20kg	FC501070-20KG
Conbextra Deep Pour 1000kg Bulk Bag (MTO)	FC501070-1000KG

*MTO (Made to Order): Minimum order quantities apply - check with Customer Service

Yield Information

• 20kg Bag Yield: 10.0 litres per 20kg bag when mixed to flowable consistency
• Allowance: Make allowance for wastage when estimating quantities required

Manufacturer Information

Conbextra Deep Pour is manufactured and supplied by Fosroc International Limited and is distributed by Parchem Construction Supplies Pty Ltd under license.

Trade Mark Designation: Conbextra is a trade mark of Fosroc International Limited, used under license by Parchem Construction Supplies Pty Ltd.

Alternative Products

Conbextra Deep Pour serves as an alternative to:

• Conbextra GP: For applications exceeding the maximum 100mm thickness limit
• Conbextra HS: For grout gaps exceeding 125mm depth
• Bulking with Conbextra Grout Aggregate: When filling/bulking out other cementitious grouts would be required

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References

• [1] Fosroc_Conbextra_Deep_Pour_TDS.pdf
• [4] Fosroc_Conbextra_GP_TDS.pdf
• [5] Fosroc_Conbextra_HS_TDS.pdf