Sika CarboDur S
Sika CarboDur S is a pultruded carbon fibre reinforced polymer (CFRP) laminate plate, supplied in continuous lengths and bonded to existing concrete substrates with a structural epoxy adhesive (Sikadur-30 LP) to provide externally-bonded reinforcement (EBR) for the flexural strengthening of beams, slabs and walls. CarboDur S plates are manufactured in standard widths from 50 mm to 150 mm and standard thicknesses of 1.2 mm and 1.4 mm, with a fibre volume fraction of approximately 68% and characteristic tensile strength of approximately 3,100 MPa, characteristic tensile modulus of 165 GPa, and characteristic strain at failure of approximately 1.7%. The plates are supplied in coiled lengths up to 250 m, which permits site cutting to length without the joints required by shorter-format CFRP products. TRSC specifies Sika CarboDur S as the default flexural strengthening laminate on remediation projects where existing concrete elements have inadequate sagging-moment capacity — typical applications are increased-loading retrofits on existing transfer beams and slabs, change-of-use retrofits where the new occupancy load exceeds the original design loading, and post-spalling repair where the flexural reinforcement has been compromised by corrosion-driven section loss. The product is installed as part of the Sika CarboDur system with a documented Manufacturer's Printed Instructions for Use (MPII) covering substrate preparation, primer application (Sikadur-32 N), adhesive (Sikadur-30 LP), plate bonding and curing.
Sika CarboDur S is TRSC's default flexural-strengthening laminate where externally-bonded reinforcement (EBR) is the appropriate engineering intervention. The product earns its specification slot for three reasons: it is a category-leading product with documented characteristic properties suitable for ULS design under FIB Bulletin 14 (the international FRP strengthening reference); it is supplied as part of an integrated system (Sikadur-32 N primer, Sikadur-30 LP adhesive, CarboDur S plate) with documented MPII; and it has the longest installation track record in Australia of any commercial CFRP plate, which matters for client and regulator confidence in the engineering basis. The most common specification pitfalls TRSC encounters in the field are: (1) substrate preparation — CarboDur S is bonded to the substrate by epoxy adhesive, and the bond strength is governed by the substrate's tensile capacity at the bond interface; substrates that have been wire-brushed only or are visibly contaminated will not develop the design bond strength, and the strengthening intervention will fail by interfacial debonding well below the design strain in the laminate; the substrate must be prepared by needle-gun, hydro-blast or grinder to expose aggregate and produce a tensile pull-off capacity of at least 1.5 MPa, verified by site pull-off testing per EN 1542; (2) end-anchorage detailing — CarboDur S develops its full design tension only when the plate-to-substrate bond is anchored over a minimum bond length (typically 200-400 mm depending on substrate strength and adhesive); short or unanchored ends produce premature debonding and require either mechanical end-anchorage (CarboShear L brackets, transverse U-wraps) or extension of the plate to a fully-bonded end; (3) overhead and vertical bonding — CarboDur S is most commonly applied to soffits where the adhesive must hold the plate against gravity until cure; the contractor must provide temporary support or pressure during the 24-48 hour cure period, and the substrate primer (Sikadur-32 N) must remain wet at the substrate / adhesive interface when the adhesive is applied. TRSC strengthening designs include the substrate preparation specification, the pull-off acceptance criterion, the end-anchorage detail, and a witness hold point for the first plate installation. The product was used on UQ Cladding strengthening where the existing slab capacity was inadequate for the revised loading scheme and CFRP laminate was the engineering choice over section enlargement.
Specification questions about Sika CarboDur S
When does TRSC specify CFRP plate over carbon fibre wrap?
What substrate condition is required for CFRP plate bonding?
How long is the CFRP plate cure cycle?
What standards govern CFRP plate strengthening design?
- ReferenceSika Sika CarboDur S Datasheet