NEW STRUCTURES

Casting into new structures

AKS should be installed to structures in the longest possible vertical panels to limit horizontal joints.

The sheets must be well secured against the formwork to avoid movement or displacement when the concrete is poured. Double sided adhesive tape is available from AKS Lining Systems for temporary fixing of AKS to formwork.

Care must be taken to avoid damage to the lining, as any damage will need to be located and repaired. The use of nails to secure AKS to the formwork is to be avoided, as it is extremely difficult to find these penetrations at a later stage.

Installation to Walls

> Cut all of the AKS sheets to the required sizes as indicated on the cutting schedule.

> Set the sheets up vertically, with the smooth side fixed to the inner face of the formwork, prior to pouring the concrete.

> To ensure that the sheets do not move during casting and that no concrete is deposited between the formwork and the sheet, one of the following procedures should be followed:

• Glue the sheet to the face of the formwork with contact adhesive.
   
• Clamp the sheets to the formwork along their top edge, above the level of the concrete to be poured. Nails should not be used as it is difficult to locate the penetration holes at a later stage. Any penetration through the liner must be clearly marked for later repair.
   
• Nylon fishing line can be used to hold the AKS in position. By lacing the last row of knobs along the edge of the sheets, the sheets can then be tensioned together.
   
• Double-sided tape can also be used to hold AKS against wooden formwork.
   

• An "H" profile with a "tear-off" front strip is recommended as a measure to properly align the AKS sheets prior to and during the casting process. The "H" profile is available as an AKS accessory.

• The AKS lining will be pressed against the face of the formwork by the spacers fitted to steel reinforcement, prior to pouring the concrete. A few knobs may be removed/trimmed to allow clearance for the spacers, or smaller spacers can be used against the knobs to ensure correct positioning of the reinforcement.
   
• It is common for concrete contractors to use ties between their shutters to establish correct wall thickness, etc. Our preferred procedure, however, is to avoid all penetrations through the liner, as far as possible, in favour of external bracing of the formwork.
   
• Once AKS and shuttering is place, the concrete is poured.
   

Soffits

> Cut AKS lining to accurate size to avoid gaps at joints then place AKS on top of the soffit formwork with the anchor knobs facing upwards

> Any hatches, manholes or other penetrations through the concrete slab must be "boxed out". The vertical side of these penetrations must be AKS lined.

• The sheets can be fixed to the adjacent reinforcement or supported by foam in the intended openings.
• The best procedure is to prefabricate these opening details.
• Knobs which clash with each other at the corner of the 90^o joint may be removed using side cutters.

 > All joints in the AKS are to be sealed before concrete is poured to avoid gaps through which "fines" may flow. Adhesive tape or our "H" profile can be used for this purpose.

Floors

Note:
The lining of floors should only be carried out after all work, which can result in damage to the floor lining, has been completed. After installing and welding of AKS to both the walls and soffits, the concrete floor surface must be cleaned by wire brushing and washing, or pressure water jetting, in order to receive a "modified" grout layer. This special grout (discussed under existing structures) has a fluid consistency.

The following means of applying AKS on floors is recommended:

 > Pre-cut all AKS floor panels and position them "dry" to ensure that the gaps between adjacent sheets on the floor and between floor/wall sheets do not exceed 3,0mm. "H" profiles may also be used for proper alignment of these sheets and to keep joints as clean as possible for final welding.

 > Areas of the floor are marked out in panels to receive the AKS lining and a modified cement primer is applied to this surface using a broom or block brush. The cement modifier is discussed later in this section dealing with the lining of existing structures.

 > Once the primer is "tack dry" the special grout is placed/poured in a 12mm thick layer onto the concrete floor.

 > The pre-cut panels of AKS are carefully rolled into the wet grout to ensure that air is not trapped beneath it. The anchor knobs automatically form a 12mm space for the grout. Please note that the AKS finished surface will follow the surface of the concrete beneath it. Care must be taken to ensure that the concrete surface is level and smooth to achieve best results.

 

 

 > The AKS must be ballasted over 100% of its area immediately after it is placed into the grout. Isolated loads may cause unevenness of the surface, so take care to position weights on planks or pallets, or position bricks or building blocks evenly over the surface. The ballast must be left in place until the grout has set.

 > Care should be taken to wipe away any grout that has squeezed up between the joints whilst the grout is still green. As soon as the initial set of the grout has taken place, the grout must be raked out of the joints between the adjacent panels to the width of the gap and depth of the lining.

Should any air remain trapped under the sheet, this may be repaired by drilling two small holes (one at each end of the cavity) and injecting grout into the cavity through the one hole until it squeezes out of the other. These holes must be clearly marked for repair by extrusion welding.