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    Featured Products: Modern Concrete Cracks and Concrete Leaks

    October 3rd, 2017 Posted by Featured Products 0 thoughts on “Featured Products: Modern Concrete Cracks and Concrete Leaks”

    Prime Flex 900 XLV polyurethane resin is a low viscosity, hydrophilic resin that reacts with water and expands to form a closed cell, watertight foam. It is typically injected under pressure to seal actively leaking joints and cracks in concrete structures, including hairline cracks. This product is independently tested and proven to meet NSF/ANSI Standard 61.5 for contact with potable water.

    AR 800 acrylate resin is a super low viscosity, hydrophilic grout that produces an elastomeric gel with variable set times. This three-component resin is used for leak sealing and soil consolidation. It is ideal for geotechnical applications in humid environments. The variable set time range is long—from minutes to more than an hour—and is adjustable in the field. The resin remains fluid until polymerization, allowing for excellent penetration, so it is a great choice for sandy or silty soils.

    When cured at a 50% concentration, it is a white flexible gel that has the consistency of a soft silicone gel with excellent adhesiveness. Humid conditions allow the gel to remain relatively constant. The gel is permanently elastic; these dimensional changes are reversible and do not degrade the gel. All-stainless steel pumps/fittings are required. This product has been independently tested and proven to meet NSF/ANSI Standard 61.5 for contact with potable water.

    Prime Flex 920 is a single-component polyurethane injection resin used to seal gushing leaks, including wide gaps, in concrete where the structure is not subject to movement. This hydrophobic, super low viscosity polyurethane reacts with water and expands to form a closed cell, watertight, rigid foam. Due to its low viscosity, 920 is also used for permeation grouting of loose soils to consolidate soil particles and increase the load-bearing capacity. (For high strength or large void filling, see Prime Flex 985.) This material requires the use of Prime Kat or Kick Fast Kat to adjust the reaction time from 4-13 seconds. (See Material Preparation below.) This product is independently tested and verified to meet NSF/ANSI Standard 61.5 for contact with potable water.

    Prime Flex Hydro Gel SX is a versatile, easy-to-use single-component, water activated, hydrophilic polyurethane injection resin for sealing actively leaking joints and cracks in below-grade concrete structures. It forms either a closed cell, watertight foam or impermeable gel depending on the water to resin mix ratio. Cured material remains flexible and has excellent adhesion. It can also be used for soil binding for slough control. Independently tested and verified to meet NSF/ANSI Standard 61 for contact with potable water.

    Prime Flex 940 polyurethane resin is a very low viscosity, hydrophobic resin that reacts with water and expands to form a closed cell, watertight flexible foam. This grout requires Prime Kat or Kick Fast catalyst, but after mixing is pumped as a single component. The set time can be varied with the catalyst concentration. This resin is used for sealing actively leaking joints and cracks in concrete structures, particularly those subject to movement or vibration. It is verified to meet NSF/ANSI Standard 61.5 for contact with potable water.

    A Truism: Modern Concrete Cracks and Concrete Leaks!

    October 2nd, 2017 Posted by Blog, Concrete Repair, Concrete Repairs, Crack Injection, Main Feature, Projects 0 thoughts on “A Truism: Modern Concrete Cracks and Concrete Leaks!”

    There are four types of concrete!

    Concrete that can crack!

    Concrete that has cracked!

    Concrete that can leak!

    Concrete that has leaked!

    Truism: This observation is obviously true and says nothing new or even interesting about concrete but if you have a problem and need a solution then:


    They are ready to help you!

    When does concrete crack and leak?

    Shrinkage cracks may occur when water evaporates from the concrete soon after it is layed during the drying process. (that is, the curing process) Hot weather can cause rapid evaporation if curing compound is not properly used to slow the evaporation and cold weather can slow the evaporation process. Fine cracks give the opportunity for water to penetrate the concrete and cause the steel reinforcement to rust and concrete degradation.

    Structural cracks when the concrete structure is over-loaded or subject to design flaws will allow water to penetrate the concrete and cause the steel reinforcement to rust leading to concrete degradation.

    Concrete cancer cracking when water penetrates into the concrete and causes the internal steel reinforcement to corrode, expand and cracks form from within allowing water to leak through the concrete element.

    Concrete cracking when the sub-base is inadequate or a washout occurs allowing water to flow under and through the concrete element.

    Soil movement below the sub-base due to natural movement or the expansion and contraction of the underlying clay earth in times of heavy rain or drought allowing water to flow below and washout the concrete element.

    Cracking due to freezing conditions followed by thawing which may also cause expansion and contraction and allow water to leak through and below the concrete element.

    Hot summers can cause cracking due to expansion of the concrete and allow the ingress of water.

    Washouts behind retaining walls may also result in structural cracking and gushing leaks.


    Fortunately, experienced Concrete Repair Contractors like, FCS Concrete Repairs, have the solutions. Experienced tradesmen, high-tech equipment and repair materials, and technical knowledge can combine to provide near permanent solutions to concrete cracking and leaking. Early intervention is also critical in enabling effective repair and cost effective solutions.

    What can be done?

    Badly damaged concrete can be replaced BUT this can be costly and involves:

    • Investigation
    • Demolition
    • Removal
    • Replacement

    Modern crack injection methods can provide a cost effective alternative solution:

    • Polyurethane injection

    Single component hydrophobic foam can be injected to stop water infiltration and to stop high pressure flowing water and to fill voids behind the structure or joints or cracking in concrete.

    Two component hydrophobic rapid setting foam can be injected. This foam is highly reactive, high strength and expands up to ten times when in contact with ground water.

    • Polyurea Silicate

    Two component low density foam to fill cavities provides structural strength and flexibility to stabilise strata.

    • Acrylic

    One component water based acrylic joint sealant and gap filler which has low adhesive and compressive strength, but high tear strength.

    • Cementitious Grout

    A combination of cement and water, plus admixes or additives to alter their properties. There are three main types – pure cement mixes (PCMs) composed of cement and water, admixed cement mixes (ACMs) composed of PCM and admixtures, and additive cement mixes (ADCMs) composed of ACM and additives.

    • Epoxy injection

    Two component, low viscosity, solvent free, moisture insensitive, structural epoxy injection resin used to seal cracks and cavities and forms an effective barrier against the infiltration of water and bonds concrete to restore structural integrity. Doesn’t bond as well to wet surfaces.

    FCS Concrete Repairs has the expertise to investigate, test, diagnose and recommend on the most appropriate and cost effective solution to your concrete cracking and leaking problem.

    How to seal leaks in concrete structures

    October 2nd, 2017 Posted by Blog, Concrete Repair, Leak Sealing, Waste Water Treatment, Water Storage, Water Treatment Plant 0 thoughts on “How to seal leaks in concrete structures”

    Prime Flex 900 XLV polyurethane resin is a low viscosity, hydrophilic resin that reacts with water and expands to form a closed cell, watertight foam. It is typically injected under pressure to seal actively leaking joints and cracks in concrete structures, including hairline cracks. This product is independently tested and proven to meet NSF/ANSI Standard 61.5 for contact with potable water.
    Recommended Uses include injecting hairline cracks, expansion joints, wide cracks, pipe joints, or pipe penetrations, or sealing active leaks in above-grade or below-grade concrete structures.

    This can be used for water treatment tanks, dams, below-grade concrete walls, tunnels, manholes and elevator service pits.

    Prime Flex 900XLV is compliant for contact with potable water, can expand and contract parallel to the crack in varying temperatures, can expand up to 600% unconfined and has a low viscosity to allow it to penetrate tight hairline cracks deep into the structure.

    When the material contacts water, it reacts to form a white, flexible gel-like foam that acts as a barrier, sealing the cracks that allowed water to leak. As the foam reacts, it expands to fill the space and bond to the concrete to hold it in place, creating a closed cell mass that does not allow water to pass through or around it. The foam’s flexibility allows it to expand and contract along with the structure it has sealed, so it remains water tight despite temperature fluctuations.

    FCS Concrete Repairs are experts in leak repair and are available to help with your concrete repair requirements. FCS Concrete Repairs are approved applicators for this product in Australia.


    Prime Flex 900 XLV: Seal leaks in concrete structures

    Repairing an Active Leak in Cracked Concrete with 900 XLV

    Case Study: Sealing a manhole with chemical grout

    October 2nd, 2017 Posted by Blog, Concrete Repair, Featured Case Study, manhole rehabilitation, Projects 0 thoughts on “Case Study: Sealing a manhole with chemical grout”

    Problem: Sinkholes had developed around storm drainage manholes in grassy areas of a military housing subdivision in Richmond, Virginia.

    Identifying the source: To pinpoint the sources of the problem, the contractor’s crew flooded the existing sinkholes and monitored the dry manhole to see where the infiltration entered.

    Solution: With on-site technical support from Prime Resins, the contractor injected Prime Flex 920 through the manhole wall to fill the voids and create a watertight curtain around the manhole. Prime Flex 920 is an expansive, hydrophobic polyurethane resin that reacts to form a rock-hard watertight mass. The grouting was done from inside the manhole because the repair locations were so deep, as much as 20 feet from the surface. Probe grouting from the surface outside the manhole can be done if the manhole is too narrow to work within.

    They installed four injection ports per pipe and injected each leak location starting at the lowest point and working up. This revealed a leaking injection hole from the previous repair attempt. Some 920 seeped out this hole and sealed it as well. The technicians repaired wide gaps around the main connection plus spalls and chips inside the collar using the activated oakum technique. They soaked oil-free oakum with Prime Flex 900 XLV and pushed it into the gaps where the reacted resin sealed the openings. The 900 XLV is a very low viscosity polyurethane and is hydrophilic, so it creates a tenacious bond with the wet concrete.

    Outcome: The crew tested their repair by flooding the sinkhole again. No water drained into the manhole: their repairs stopped the infiltration. Finally, they removed the ports and plugged the holes with hydraulic cement.

    Read the complete case study here.

    FCS Concrete Repairs are experts in leak repair and are available to help with your concrete repair requirements. FCS Concrete Repairs are approved applicators for Prime Resins in Australia.

    Request a quote here.

    Sikadur® Combiflex®

    June 23rd, 2017 Posted by Featured Products 0 thoughts on “Sikadur® Combiflex®”

    Sikadur-Combiflex can be applied on dry or damp substrates. It shows remarkable adhesion to concrete, iron and steel and is perfect for joints with very large expansion. Sikadur is also weather and waterproof. The Sikadur-Combiflex system is approved for potable water contact.

    Sikadur CombiFlex


    • Sealing internal joints in new or refurbished concrete water tanks, reservoirs, pipelines, sewers and swimming pools
    • Joints in bunds and tanks for heating oil and fuel oil, etc
    • Sealing underwater joints in situ
    • Sealing joints in large decks of multi-storey car parks
    • Sealing joints in tunnels, silos and roofs
    • Sealing and repairing joints that have more movement than can be accommodated by conventional elastomeric wet applied sealants

    Characteristics and Advantages

    • Applicable on dry and damp surfaces
    • Quick hardening in low temperatures
    • Three adhesive types for application between 5°C and 45°C
    • For large expansion joints or cracks
    • Of permanent elasticity even at low temperatures
    • Weather resistant / Water resistant
    • Approved for use in potable water (AS4020:2005)
    • Rot resistant
    • Resistance against many chemicals
    • Excellent adhesion to most conventional building materials
    • Perforations along edges of Combiflex provide “rivet effect” and adds mechanical fixing to augment chemical bond
    • No need to remove failed sealant from old joints before use


    Light Grey


    WATCH Video: Sikadur Combiflex for Movement Joints or Movable Cracks



    Sikadur® 31

    June 23rd, 2017 Posted by Featured Products 0 thoughts on “Sikadur® 31”

    Sikadur-31 is a thixotropic adhesive mortar based on a 2-component solvent free epoxy resin containing fillers. Sikadur-31 will bond and fill a wide variety of building and construction materials and may be used in both dry and damp conditions thereby providing an adhesive mortar ideally suited to site application. It is available in three grades: rapid, normal and long pot life for low, medium and high ambient temperatures respectively.

    Sikadur-31 FCS


    Sikadur-31 may be used as a thin layer levelling mortar, repair mortar or adhesive for most building materials (concrete, brick, stone, ceramics, cement mortar, GRC, fibrous cement, iron and steel and epoxy mortar). Sikadur-31 may also be used to anchor holding down bolts, starter bars etc. as a bonding bridge between old concrete and Sikadur-41 mortar. The material is also ideally suited for bonding of external reinforcement and as a general structural adhesive. Special higher strength grades of the material are available for segmental bridge and other construction.

    Characteristics and Advantages

    • Chemical resistant
    • Insensitive to moisture during application, cure or whilst in service
    • Applicable at low temperatures
    • Excellent adhesion to most building materials even when damp
    • High abrasion resistance
    • Approved for use in contact with potable water
    • High early strength
    • High tensile and flexural strength
    • Supplied in factory proportioned units
    • Easily applied – thixotropic, non-sag
    • Proven in service
    • Shrink free
    • Two components of different colours enabling visual control of degree of mixing.


    Part A – White Part B – Dark Grey Mixed product uniform grey colouration

    See Complete Product Info Here 

    Sikaflex® PRO-3

    June 23rd, 2017 Posted by Featured Products 0 thoughts on “Sikaflex® PRO-3”

    Sikaflex-PRO is a one component, thixotropic, polyurethane based joint sealant. It cures under the influence of atmospheric moisture to form an elastomeric material with adhesive properties, in some cases without the need for priming of the substrate.

    SikaFlex Pro3 - FCS


    As an elastic joint sealant for:

    • Expansion joints in buildings and civil structures above and below ground.
    • Construction joints.
    • Joints in precast concrete elements.
    • External walling and cladding joints.
    • Infill panel joints.
    • Curtain walling.
    • Sanitary installations.
    • Sealing around window and door frames.
    • Flexible draught proofing.
    • Sealing penetrations in walls or floors for ducts, piping etc.
    • Retaining walls.
    • Sealing joints in water retaining structures (water reservoirs)

    Characteristics and Advantages

    • New Sikaflex-PRO will bond well to well cleaned Sikaflex-PRO.
    • Excellent adhesion on all cement based materials, brick ceramics, polyurethane, epoxy, most polyester, most metals and most timbers.
    • High durability.
    • Good weathering resistance.
    • Non-sag on vertical and soffit joints up to 30 mm width.
    • Short skinning time.
    • Short cut off string, even after storage.
    • Ready for immediate use – no mixing, saves time.
    • No potential mixing errors or wastage due to mixed quantities being greater than required.
    • Non-corrosive.


    Black, Brick Red, Dark Amber, Concrete Grey, Japan Beige, Sandstone, White, Pale Brown (600ml), Redwood, Off White, Dark Grey

    ANCIENT 2,000 Year Old Concrete

    June 23rd, 2017 Posted by Blog 0 thoughts on “ANCIENT 2,000 Year Old Concrete”

    Will the Roman 2000 year product guarantee stand up for today’s concrete mix designs?

    Ancient concrete mixes have stood the test of time and withstood all of the environmental attacks known to mankind for over 2000 years. Today’s concrete, however, is susceptible to environmental damage and often needs protection or repair or, in the extreme, reinstatement within thirty (30) years.

    What is the secret to 2000 year old concrete?

    Roman concrete mix designs were simple. No admixtures. No risk from sulphates. No issues with the penetration of water. No steel reinforcement to rust. No concrete cancer.

    Ancient concrete consisted of just three elements:

    • The paste – limestone (crushed and burnt)
    • The “sand” – volcanic ash
    • The aggregate – large lumps of rock

    The burnt volcanic ash has an amorphous silica structure with many holes in the molecular network which fill with calcium hydroxide upon mixing with wet lime and becomes the paste which binds the rocks together. Sand in modern concrete however is crystalline and does not have holes in the molecular structure to accommodate the cement paste.

    Ancient Romans mixed their concrete product by hand and tamped the mortar into place thus minimising the water content and therefore created a low slump and highly durable mix.

    They also discovered that the volcanic ash developed hydraulic properties when mixed with lime and then realised the advantages of hydraulic lime, i.e. cement that hardens underwater.

    The Pantheon

    Built by Rome's Emperor Hadrian and completed in 125 AD, the Pantheon has the largest unreinforced concrete dome ever built.

    The Trajan's Market

    Trajan's Market is a large complex of ruins in the city of Rome, Italy, located on the Via dei Fori Imperiali, at the opposite end to the Colosseum.

    The Colloseum

    Also known as the Flavian Amphitheatre

    Modern Fly Ash Mix Designs.

    Some modern concrete mixes use fly ash as a supplementary cementitious material which delivers improved workability and, like the Ancients, later age strength and high durability.

    Modern Concrete Mixes.

    But unlike those majestic Roman structures, today’s cities are plagued by crumbling concrete tower blocks and decaying bridges and expressways.

    Today’s concrete is made using Portland cement, coarse and fine aggregates of stone and sand, and water steel reinforcement.

    Admixtures are chemicals added to the concrete mix to control its setting properties and are used primarily when placing concrete during environmental extremes, such as high or low temperatures and windy conditions.

    Although steel reinforced concrete is one of the most widely used construction materials around the world, it can suffer degradation over time due to the embedded steel corroding, causing the concrete to crack and “spall”.


    In extreme situations, the integrity of the structure may be lost, resulting in the need for partial or complete demolition. Corrosion affects all reinforced concrete buildings and structures to some extent, with an estimated annual cost of billions of dollars to national economies. In addition, loose damaged pieces of spalled concrete falling from buildings and structures is a real safety risk.

    When chlorides, carbon dioxide gas and other aggressive agents penetrate concrete, they initiate corrosion of reinforcement that typically results in cracking, spalling and weakening of the concrete infrastructure. As reinforcing bars rust, the volume of the rust products can increase to many times that of the original steel, increasing pressure on the surrounding material which cracks the concrete. The cracks can then propagate to delamination and eventually spalling of the concrete.

    Usually, the most exposed elements deteriorate first but because the active corrosion may take five to 15 years to initiate cracks in the concrete, much of the actual corroded reinforcement is not visible. Such corrosion is often called “concrete cancer”, because it appears as if the structure was being eaten away from the inside.

    We have now realised these issues with modern concrete, for example:

    • Thousands of passengers have been travelling over Hawkesbury River Rail Bridge connecting Sydney to the Central Coast every day, despite a crucial supporting pylon being riddled with “concrete cancer”. With cracks up to two metres long, the pylon is so severely deteriorated it crumbles away like powder.


    • Edgewater Towers in St Kilda’s Marine Parade is a notorious example of how costly concrete cancer can be. The modernist block of 100 apartments sprang up in 1961 but by the 90s spalling was ravaging its balconies. Issues were still being remediated as recently as 2011.


    • Gold Coast’s Ageing High-Rises. Bodies corporate of these ageing buildings are now faced with the prospect of either having to spend hundreds of thousands of dollars, if not millions of dollars, rectifying concrete cancer and other building defects, or they look to cash out and sell to developers.


    • It was recently revealed that one building — the landmark Focus Apartment tower — needed $2.7 million in repairs to prevent “extremely dangerous” deterioration from concrete cancer or spalling.


    • The 20-storey Iluka Surfers Paradise high-rise was demolished after concrete cancer destroyed its structural integrity.


    • Dozens of 40-year-old Gold Coast high rise apartment towers built in the 1970s face million-dollar concrete cancer repair jobs similar to the $215 million in repairs needed by Brisbane’s City Hall.


    • When it was finished in 1978, the 67-storey MLC Centre in Martin Place, Sydney, was not only Australia’s tallest office building, but also the biggest reinforced concrete structure in the world. Thirty-three years later in 2011, the Harry Seidler-designed structure is showing its age. Its concrete facade is breaking up and the owners have agreed to spend $100 million repairing it in an operation that will go 24 hours a day, seven days a week for four years.


    • The Sydney Opera House might be one of the world’s most iconic buildings but it faces potentially significant conservation challenges, a US philanthropic organisation says. The Getty Foundation has awarded the Sydney Opera House Trust $US200,000 ($A224,000) for a study of the concrete elements of the building and to develop long-term conservation strategies should it become necessary in the future.


    Concrete Repair Methodology

    Concrete repair methods need to provide a permanent solution in order to avoid a recurrence. FCS Concrete Repairs will Investigate, Diagnose, Test and Recommend the appropriate solution which will depend on the extent of damage and the feasibility of the repair or if necessary reinstatement of the concrete element affected.

    The nature and type of repair will be determined by:

    • Extent of corrosion of reinforcement
    • Extent of loss of strength of reinforcement
    • Extend of loss of the bond between the reinforcement and the concrete
    • Extent of deficiency in concrete cover over reinforcement
    • Extent of deflection due to cracking in the tensioned areas.
    • Extent of honeycombing in concrete
    • Extent of porosity of concrete
    • Extent of damage and loss of strength due to sulphate attack.
    • Extent and width of cracking


    Maintenance of Concrete Expansion Joints

    June 23rd, 2017 Posted by Insights, Joint Sealing, Projects 0 thoughts on “Maintenance of Concrete Expansion Joints”

    FCS Concrete Repairs are fully resourced to provide maintenance and repair services for concrete Expansion Joints in commercial, industrial and residential properties.

    Expansion Joints in carparks and hardstand areas can also be repaired through permeation grouting of the sub-base to fill voids and polyurethane injection to lift the slab back to level where there is a step in the joint due to subsidence or washout. This process can avoid extremely costly and disruptive demolition and replacement of the concrete slab.

    FCS Concrete Repairs are experts in the field of concrete repair and are approved contractors for the major suppliers of joint sealants and joint repair products.

    You can rely on FCS Concrete Repairs, as we are Quality Accredited under the International Standard ISO 9001: 2015 to carryout quality workmanship with full backup services, if required.

    Expansion Joint Re-sealing

    Expansion Joints in concrete floors and walls control movement and over time the joint sealant can deteriorate. The sealant can be removed and replaced to ensure that the joint is waterproof and performs as required.

    Expansion Joint Reinstatement

    Expansion joints require that the facing edges of the adjoining concrete slabs are sound so that the flexible joint sealant forms a strong bond between the concrete slab or wall elements. Industrial floors, which may be on ground or suspended, require regular maintenance as they are vulnerable to impact damage from mobile plant including forklifts which are often hard-wheeled. Broken and crumbling edges along an expansion joints is an indication of future extensive and costly damage.

    Where considerable damage has occurred it may be necessary to carry out more extensive repair including concrete saw cutting and edge reinstatement. Regular inspection is a cost saving option to ensure that the jointing material is still performing and protecting the concrete joint edge faces. Heavy duty repair mortars may be required to re-construct the joint and these can be fast drying/curing to minimise downtime. FCS Concrete Repairs can provide professional advice in this regard.

    Widening Expansion Joints

    Expansion Joints may widen over time due to slab movement and damage.

    Narrow expansion joints can provide a smoother transition across the joint and minimise future damage. FCS Concrete Repairs can re-form wide expansion joints cost effectively to reduce the gap and the impact over widening joints.

    Expansion Joint Remediation – Wyong NSW

    June 23rd, 2017 Posted by Joint Sealing, Projects 0 thoughts on “Expansion Joint Remediation – Wyong NSW”

    Product Used:

    Sikaflex® Tank N is a 1-part Elastic Sealant for Joints Exposed to Chemicals.

    Sikaflex® Tank N is used in areas for the storage, filling and handling of water polluting liquids such as floor joints in petrol stations, joints in handling areas, storage tanks and containment bunds, movement- and connection joints according to IVD data sheet no. 1. I. E. in workshops and parking garages



    Remediation Process:

    Prior to Sealing:

    • Removal of existing joints
    • Clean out existing expansion joints to depth of min 50mm using road saw with flat wire wheel
    • Clean out joints. Vacuum and sweep joints
    • Repair cracked concrete by pinning and stitching

    Sealing to Expansion Joints:

    • Tape up sides of joint repair with Masking Tape to avoid spilling over
    • Install foam backing rods into the joints
    • Prime seal expansion joints with Sika® Primer-3-N
    • Installation of Sikaflex® Tank N into joint at a min. depth of 15mm
    • Remove masking tape
    • Final Inspection and hand-over.

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