PRi GP 2

• Gaseous expansion system compensates for shrinkage and settlement in the plastic state
• No metallic iron content to cause staining
• Pre-packed material overcomes onsite batching variations
• Develops high early strength without the use of chlorides
• High ultimate strength ensures the durability of the hardened grout
• Free flow ensures high level of contact with load bearing area

• Foundation surface
  The substrate surface must be free from oil, grease or any loosely adherent material. If the concrete surface is defective or has laitance, it must be cut back to a sound base. Bolt holes and fixing pockets must be blown clean of any dirt or debris.
• Pre-soaking
  Several hours prior to placing, the concrete substrates should be saturated with fresh water. Immediately before grouting takes place any free water should be removed with particular care being taken to blow out all bolt holes and pockets.
• Base plate
  It is essential that this is clean and free from oil, grease or scale. Air pressure relief holes should be provided to allow venting of any isolated high spots. Always use appropriate size of trowel with respect to the tile size and the density of the tile.
• Levelling shims
  If these are to be removed after the grout has hardened, they should be treated with a thin layer of grease.
• Formwork
  The formwork should be constructed to be leakproof. This can be achieved by using foam rubber strip or mastic sealant beneath the constructed formwork and between joints. In some cases, it is practical to use a sacrificial semi-dry sand and cement formwork. The formwork should include outlets for pre-soaking.
• Unrestrained surface area
  This must be kept to a minimum. Generally, the gap width between the perimeter formwork and the plate edge should not exceed 150mm on the pouring side and 50mm on the opposite side. It is advisable, where practical, to have no gap at the flank sides.

For best results a mechanically powered grout mixer should be used. When quantities up to 50kg are used, a heavy-duty slow speed drill (400-500 rpm) fitted with a paddle is suitable. Larger quantities will require a heavy-duty mixer. To enable the grouting operation to be carried out continuously, it is essential that sufficient mixing capacity and labour are available. The use of a grout holding tank with provision to gently agitate the grout may be required.

The quantity of clean water required to be added to a 20kg bag to achieve the desired consistency is given below:
Pourable: 3.30 litres

Flowable: 3.60 litres

The selected water content should be accurately measured into the mixer. The total content of the PRi GP2 bag should be slowly added and continuous mixing should take place for 5 minutes. This will ensure that the grout has a smooth even consistency.

• At 300C place the grout within 20 minutes of mixing to gain full benefit of the expansion process.
• PRi GP2 can be placed in thicknesses up to 100mm in a single pour when used as an underplate grout.
• For thicker sections it is necessary to fill out PRi GP2 with well graded silt free aggregate to minimise heat build-up. Typically, a 10mm aggregate is suitable. 50 – 100% aggregate by weight of PRi GP2 can be added.
• Any bolt pockets must be grouted prior to grouting between the substrate and the base plate.
• Continuous grout flow is essential. Sufficient grout must be prepared before starting. The time taken to pour a batch must be regulated to the time to prepare the next one

On completion of the grouting operation, exposed areas should be thoroughly cured. This should be done by the use of Con- cure WB curing membrane, continuous application of water and/or wet hessian.

PRi GP 2 grout should be removed from tools and equipment with clean water immediately after use. Cured material can be Removed mechanically, or with reawakens.

Tensile Strength                                 3.5N/mm² @ 28 days

(W/P – 0.18)

Pull-out bond strength                      17 N/mm² @ 7 days

(W/P – 0.18)                                        20 N/mm² @ 28 days

Time for expansion                           Start: 20 minutes

(After mixing)                                     Finish: 120 minutes

Fresh wet density                              approximately 2220kg/m³ depending on actual consistency used

Young’s modulus (ASTM D469 – 94)                  28 kN/mm²

Dynamic load resistance                  Specimens of PRi GP-2 remained undamaged even after subjecting them

                                                              To alternate loads of 5N/mm² & 25N/mm² at the rate of 500 cycles / minute

                                                              For two million cycles.         

Coefficient of thermal expansion   11 x 10 -6/ 0 C

Unrestrained expansion                   2 – 4 % in the plastic state enables to overcome shrinkage.

Pressure to restrain                          0.004 N/mm² approx.

Flow Characteristics                         The maximum distance of flow is governed by the gap width and the head of

                                                             The grout. Typical data for flow design assuming grout is poured immediately

                                                             After mixing is given in the table below:

Low temperature working
When the air or contact surface temperatures are 100C or below on a falling thermometer, warm water (30 – 400C) isrecommended to accelerate strength development. For ambient temperature below 100C the formwork should be kept in place for at least 36 hours. Normal precautions for winter working with cementitious material should then be adopted.
High temperature working
At ambient temperatures above 400 C, cool water (below 200C) should be used for mixing the grout prior to placement

Allowance should be made for wastage when estimating quantities required. The approximate yield per 20 kg bag for different consistency is:
Consistency Pourable Flowable
Yield (litres) 10 10.64

PRi GP2 has a shelf life of 6 months if kept in a dry store in sealed bags. If stored in high temperature and high humidity locations, the shelf life may be reduced.

• PRi GP2 is alkaline and should not come into contact with skin and eyes. Inhalation of dust during mixing should be avoided.
• Gloves, goggles and dust mask should be worn.
• If contact with skin occurs, it shall be washed with water. Splashes to eyes should be washed immediately with plenty of clean water and medical advice sought.