Mapei Mapegrout Hi-Flow SP

Technical Characteristic

Mapegrout Hi-Flow SP is a ready-mixed powder composed of highly resistant cement, selected aggregates, special additives and synthetic fibres prepared according to a formula developed in MAPEI research laboratories.

Mapegrout Hi-Flow SP, once mixed with water, becomes a highly fluid mortar, suitable for pouring into formwork without separation of the aggregates even when forming great thicknesses.

Mapegrout Hi-Flow SP, once cured, has the following qualities:

• very high flexural and compressive strength;
• modulus of elasticity and coefficients of thermal expansion and permeability to water vapour similar to those of high quality concrete;
• waterproof;
• high adhesion to old concrete, providing it has been saturated with water beforehand, and to reinforcing rods especially if they have been treated with Mapefer or Mapefer 1K, two-component and one component;
• high resistance to wear due to abrasion.

Mapegrout Hi-Flow SP is recommended for voids up to 5 cm for single placing. For greater thicknesses, it is recommended to add suitable graded aggregates from 30 to 50% by weight of the product, only after consulting MAPEI Technical Assistance. In order to improve its flexural strength and shock resistance, Mapegrout Hi-Flow SP can be mixed with galvanised steel fibres 30-40 mm long in a ratio of 40-60 kg of fibres for every m3 of mix.

Mapegrout Hi-Flow SP meets the requirements defined by EN 1504-9 (“Products and systems for the protection and repair of concrete structures - Definitions, requirements, quality control and evaluation of conformity - General principles for the use of products and systems”) and the minimum requirements claimed by EN 1504-3 (“Structural and non structural repair”) for structural mortars of class R4.

Mapegrout Hi-Flow SP meets the requirements of AS/NZS 4020:2005. (Eurofins | ams Report Reference No 1609356)

Application Procedure

Preparing the substrate

• Remove degraded and loose concrete until the substrate is solid, resistant and rough. Any previous restoration work which is not soundly bonded should also be removed.
• Clean the concrete and reinforcing rods by sandblasting, to remove all dirt, rust, cement laitance, grease, oil and previously applied paints.
• Soak the substrate with water.
• Allow the excess water to evaporate before pouring in the mix; if necessary, use compressed air to facilitate the removal of the free water.

Preparing the mortar

• Pour the quantity of water corresponding to the required consistency into the concrete mixer (see the table).
• Start the mixer and slowly and continuously pour in Mapegrout Hi-Flow SP.
• Mix for 1-2 minutes, scrape any unmixed powder off the sides of the mixer and remix for another 2-3 minutes until the mix is fluid and free from lumps.
• Depending on the quantity being prepared, a mortar mixer or drilling machine with a stirrer attachment can be used.
• Avoid stirring an excess of air into the mix.
• Only in exceptional circumstances should the slurry be mixed by hand. Only where it is absolutely necessary, prepare small quantities and mix for at least 5-6 minutes until the slurry is completely smooth and even. It should be remembered that manual preparation requires greater quantities of water, which are detrimental to some of Mapegrout Hi-Flow SPcharacteristics, such as mechanical strength, shrinkage, waterproofing, etc.
• The expansion of Mapegrout Hi-Flow SP has been calculated to compensate for the hygrometric shrinkage.
• In order to be effective, the forces of expansion must be countered with suitable reinforcement or formwork around the substrate.
• The expansion phase is completed during the first days of curing.

Applying the mortar

• To facilitate the expulsion of air, pour Mapegrout Hi-Flow SP continuously into the moulds. Water from Mapegrout HiFlow SP must not be absorbed by the formwork, which should be pre-treated with a form-release oil (e.g. MAPEI’s DMA1000 Form Release Agent).
• The pour does not need to be vibrated. Make sure that all the parts to be repaired have been filled. If necessary, use sticks or rods to tamp the slurry into particularly difficult areas.
• The repair process is complete when a coat of Elastocolor is applied on the surfaces.

Precautions to be observed during application and curing

• No special precautions need to be taken when the temperature is around +20°C.
• In hot weather, it is advisable to prevent the material from being exposed to the sun and to use cold water for preparing the mix.
• When the temperature is low, the water used for the mix should be around 20°C
• Once poured, Mapegrout Hi-Flow SP must be cured very carefully. The surface of the mortar exposed to air must be protected against the rapid evaporation of water particularly in warm and windy environments, as this will cause surface cracks due to plastic shrinkage.
• Spray water onto the surface during the first 24 hours of curing or apply a suitable anti-evaporation product (Mapecure SP).

Cleaning

Before hardening, the slurry can be cleaned from tools with water. After setting, cleaning is very difficult and it can only be removed mechanically.