Cintec Anchor System
The Cintec Anchor System is a fabric-sock cementitious-grouted reinforcement anchor for the structural strengthening, crack stitching and connection design of masonry, concrete and stone substrates, with particular application to heritage and historic structures. The anchor consists of a stainless steel rod (typically 12 mm to 32 mm diameter, in lengths up to 12 m) inserted into a permeable fabric sock (typically polyester) sized to fit the over-drilled host hole in the substrate, with the assembly grouted in place using the proprietary Cintec Presstec cementitious grout pumped under pressure. The Presstec grout exudes through the fabric sock under pumping pressure, locking the assembly mechanically into the surrounding substrate while the sock contains the grout to prevent loss into voids, fissures or cavities in the host material — the key engineering advantage on heritage masonry where the substrate is rarely homogeneous. Cintec anchors are used for brick wall ties (long-span replacement of failed wall ties), heritage strengthening of stone and masonry buildings (post-installed reinforcement of arches, vaults, towers and parapets), and structural connections in materials where conventional injection adhesives or expansion anchors are unsuitable. TRSC specifies Cintec on heritage remediation projects where the substrate condition or the engineering load case exceeds the application envelope of Helifix CemTie.
The Cintec Anchor System is TRSC's heritage-engineering anchor specification for the higher-load and longer-embedment applications that exceed the Helifix CemTie envelope. The product is selected over alternatives (Helifix CemTie, conventional injection adhesive anchors, near-surface mounted FRP) on three grounds: (1) substrate accommodation — the fabric sock contains the grout in heterogeneous, voided or fissured masonry where conventional grout would simply flow away into the substrate, which is the engineering reason Cintec dominates the heritage stone-masonry strengthening category internationally (cathedrals, castles, listed historic buildings); (2) high-load capacity — Cintec anchors at 32 mm diameter and 6 m+ embedment deliver tension capacities measured in hundreds of kilonewtons, which is the appropriate specification for tower-stabilisation, parapet-tying and arch-restraint applications where the design tension exceeds CemTie capacity; (3) long-embedment capability — the system is supplied in lengths up to 12 m, permitting through-thickness reinforcement of thick stone walls and post-installed reinforcement at deep embedments not achievable with other systems. The most common specification pitfalls TRSC encounters in the field are: (1) sock sizing — the fabric sock must be sized to the host hole diameter such that the grout pumping pressure expands the sock against the substrate; oversize socks fail to expand, undersize socks tear under pumping pressure; the sock specification is supplied by Cintec for each anchor configuration and must not be substituted; (2) grout pressure control — the Presstec grout is pumped under controlled pressure (typically 2-5 bar); over-pressure ruptures the sock or splits the substrate, under-pressure produces incomplete sock expansion; the contractor must use a calibrated pump with pressure gauge and demonstrate the pumping technique on the first installation as a witness hold point; (3) installer certification — Cintec installations are supplied as engineered-system installations with Cintec-trained installers; substituting a generic contractor without Cintec system training is not appropriate and TRSC specifications require Cintec-approved installer engagement. The Cintec system was specified on the Victory Hotel post-fire remediation for the strengthening of fire-damaged stone masonry where the substrate condition (heat-damaged, fissured) made conventional anchor systems inappropriate.