Cintec Anchors

Old, historic and listed buildings and monuments often require structural repairs, having deteriorated over time.  Traditionally pattress type plates and tie bars were used to stabilise these structures, and repair the cracks in the walls.  However, these solutions are not always the most aesthetically pleasing.

Cintec anchors are much more suitable for the restoration of historic and heritage buildings, as they are less obtrusive aesthetically than conventional tie bars and pattress plates.  Cintec Anchors are especially suited for the repair of cracks in rubble filled or voided stone walls.

Stronghold Preservation are Cintec anchors approved installers.

How Cintec Anchors Work

The Cintec anchor system comprises of a steel bar (or multi-bars) enclosed in an elasticated porous fabric sleeve.  Holes are diamond drilled into the masonry or stone, into which the anchors are placed.  The grout is pressure injected under controlled low pressure, which fills through a grout tube from the rear to the front, until the sock is entirely filled.  

Cintec Sock

The elasticated Cintec sock serves several functions; It initially acts as a formwork for the high strength grout, allowing it to expand tightly into the drilled hole. It will aslo expand a further 30-50% more than the drill hole size, which allows the grout to expand into the natural voids and contours of the wall. This expansion into the voids provides a strong mechanical fixing within the structure, along the entire length of the anchor. This can reduce the requirement for any unsightly pattress plates on the exterior of the structure, as the anchor is bonding along it's length rather than having a point load at the end plates. 

The elasticated fabric sock allows most of the water content of the cementitious grout (Grout milk) to pass through, whilst leaving the concentrated, dense, non-shrink solids within the sock.

Additionally, by allowing the 'grout milk' to pass through the fabric sock it creates a chemical bond with the substrate in contact with the anchor. 

Inflated Cintec Anchor Detail

          

The grout is injected through a circular hollow section bar or plastic grout tube. This allows the anchor to be pumped from one end, filling the sock up from the rear. This process of grouting from the rear to the front provides a high degree of quality control, as the final part to inflate is at the front.

The grout is injected under pressure which expands the elasticated Cintec Sock Anchor into natural voids within the wall, creating a mechanical and chemical bond within the wall

The load is imparted more evenly than traditional anchors, due to the bond created by the expansion into the natural voids over the full  length of the anchor.

Quality Control

The installation process for the Cintec anchor system automatically provides the user with a high degree of quality control. As most anchor holes are 'blind' ie the operative cannot see the far end, there is a risk, with other systems, that the furthest end may not be correctly filled or surrounded in grout. With the Cintec Anchor system, the sock will not inflate at the front (visible end) until the remainder of the anchor has filled with grout, therefore the installer can ensure that the entire anchor is fully grouted. As a licensed Cintec Approved Installer, Stronghold Preservation have been trained in these techniques.

Specialist Drilling

As the Cintec anchors are often installed in historic buildings that are unstable, the drilling system msut be sympathetic to the structure and avoid causing further damage. Specialist diamond drilling techniques are used to drill long holes, which can be in excess of 12m. The diamond drilling system creates little vibration and is extremely accurate over long distances, making it ideal for historic buildings and structures.

Often when there are structural problems in historic buildings, the walls are voided or rubble filled, making any drilling difficult, due to the fact that the loose core often collapses into the drill hole after the drill bit is removed, making the insertion of the anchor difficult if not impossible. Special hollow, extendable diamond cores are used to keep the drill hole open and prevent the hole closing in, allowing the Cintec Anchor to be inserted.

Advantages of Cintec Anchors

• Ideal for void filled or loose rubble filled walls
• Capable of being installed in long anchor lengths - Up to 30m Cintec anchors have been installed
• Effective high strength anchors are possible in poor quality, soft masonry 
• Ideal for bridging cavities, without grout loss
• Good quality control in long 'blind' holes - Sock inflation at front provides proof that the entire anchor is surrounded by grout
• Sympathetic with existing structures - Cintec uses natural cementitious, non-resin grouts
• Minimal visibility when installed - No pattress plates necessary
• Resistant to fire compared to resin fixings
• Approved by heritage organisations 

Applications for Cintec Anchors

The Cintec Anchors are suitable for use in: