About Sika SikaWrap-600 C

SikaWrap-600 C is one of the heavier fabrics in Sika’s carbon fibre strengthening range, built around unidirectional high-strength carbon tows carried at a nominal areal weight of roughly 600 g/m². The fibres run in a single 0-degree direction and are held in a stable sheet by a light stitching or weft, so when the fabric is impregnated with epoxy on site it cures into a thin, extremely stiff laminate that behaves like externally bonded steel reinforcement, but at a tiny fraction of the weight. It is a wet lay-up (hand lamination) system, which means the same roll can be cut and shaped to wrap a circular column, follow the soffit of a beam or dress the haunch of a bridge girder without any pre-cured plates or heavy lifting gear.

For engineers and contractors in India, the appeal is practical. A structure that has lost capacity through corrosion, overloading, a change of use or a code upgrade can be brought back into service in days rather than through demolition and recasting. Space Arc Engineering supplies SikaWrap-600 C together with the matching Sikadur primers and saturating resins as a complete, warranty-friendly system, and supports specifiers across Delhi NCR and Pan-India with substrate assessment, wrap-scheduling guidance and trained applicators so the fabric is installed the way the design assumed.

The technical insight

The mechanism is externally bonded reinforcement (EBR). Once cured, the carbon laminate is chemically bonded to the concrete through the Sikadur epoxy, so as the member deflects and the tension face tries to elongate, that strain is transferred by shear through the adhesive into the carbon fibres. Because the fibres carry a tensile strength in the order of 4,900 N/mm² at a modulus near 242,000 N/mm² (comparable to steel’s stiffness but roughly a fifth of its density), a laminate only about 0.33 mm thick per layer can take up a large share of the tensile demand. Orientation is everything: the fibres only work along their length, so the wrap must be aligned with the principal tensile stress — longitudinally for flexure, transversely as hoops for shear and for column confinement. In confinement, the hoop wrap develops passive lateral pressure on the core, which raises both the compressive strength and, more importantly, the ductility a column can deliver under seismic drift. The governing limit is almost never the fibre strength itself but the quality of the bond, which is why substrate preparation and full resin saturation decide whether the system reaches its design capacity.

Where it is used

• Flexural strengthening of reinforced-concrete beams and slabs by bonding fabric to the tension soffit
• Shear strengthening of beams and girders using transverse or U-wrapped fabric
• Seismic confinement and ductility upgrade of RC and masonry columns
• Rehabilitation of road and rail bridge decks, piers and girders after load rating or deterioration
• Reinstating capacity in structures weakened by rebar corrosion, fire or concrete distress
• Strengthening of silos, chimneys, water tanks and other cylindrical/industrial shells
• Upgrading floors and framing for change-of-use or increased live loads in industrial buildings
• Local strengthening around new openings cut into existing slabs and walls

Key advantages

• Very high tensile capacity for its thickness, so strengthening adds negligible dead load or section size
• Corrosion-proof carbon fibre suits marine, coastal and chemically aggressive environments
• Hand lay-up conforms to columns, curves, haunches and confined spaces without heavy plant
• Fast installation that keeps structures partly in service and shortens downtime
• Complete engineered system with matched Sikadur primer and saturating resins from one source
• Unidirectional fibres let the designer place strength precisely along the load path
• Thin, low-profile laminate is easy to over-coat, plaster or fire-protect after cure
• Backed by Space Arc technical support and trained applicators across Delhi NCR and Pan-India

Limitations & considerations

• Performance depends entirely on the bond, so it demands sound, prepared substrate with adequate pull-off (tensile) strength
• Carbon fibre is not fire-resistant on its own and normally needs a protective coating or board for fire rating
• Being a wet lay-up, results are sensitive to workmanship — resin ratio, saturation and roller consolidation must be controlled
• Uniaxial fabric strengthens only along the fibre direction; multi-directional demand needs additional layers or orientations
• Requires design by a competent structural engineer; it is not a like-for-like patch material
• Epoxy cure and bond are temperature- and moisture-sensitive, so hot, damp or wet conditions need managing on site

Selection & best practice

Specifications

Industry use cases

How we position Sika SikaWrap-600 C

SikaWrap-600 C sits at the heavy end of Sika’s wet lay-up FRP range; where design demand is lighter, mid-weight fabrics such as SikaWrap-300 C or the woven SikaWrap-601 C IN may be more economical, and for very high, precisely defined flexural demand the pre-cured Sika CarboDur plate system can be simpler to install. It is always paired with the Sikadur-330 primer/adhesive and Sikadur-300 saturating resin, which we supply as a matched kit. Within our wider portfolio, engineers standardised on Fosroc will find a directly equivalent wet lay-up carbon fabric in the Nitowrap EP(CF) system, so the choice between them usually comes down to which brand the specification or existing works already call up.

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