When degraded vertical or overhead concrete demands a medium-strength structural repair, achieving a non-slump application without formwork is critical. Mapegrout T40 delivers a thixotropic, fibre-reinforced mortar that holds its shape, rebuilds concrete sections, and restores integrity where it matters most.
Mapegrout T40 is a premixed, fibre-reinforced, shrinkage-compensated mortar engineered for medium-strength (40 MPa) structural concrete repairs. Its thixotropic formulation allows for application in substantial thicknesses on vertical and overhead surfaces without slumping or needing formwork. This makes it ideal for reconstructing degraded concrete coverings of reinforcing bars and repairing corners of pillars, beams, and balconies, ensuring the repaired section matches the performance characteristics of medium-quality concrete.
Prepare the substrate by removing all degraded concrete and thoroughly cleaning reinforcing bars by sandblasting. Saturate the concrete with water, ensuring no excess water remains before application. Mix Mapegrout T40 with water at low speeds to prevent air entrainment; a 25 kg bag requires approximately 3.8 to 4.1 litres of water for a trowel or spray consistency. For improved internal curing and reduced plastic and hydraulic shrinkage, add Mapecure SRA at a dosage of 0.25% by weight to the mix. The mortar remains workable for about 1 hour at 20°C.
Reinforcing bars must be treated with Mapefer or Mapefer 1K before applying Mapegrout T40. Apply the thixotropic mortar by trowel or spray in layers up to 30-35 mm on vertical or overhead surfaces without formwork. For thicknesses over 2 cm without formwork, the surface must be reinforced and roughened, ensuring a minimum 20 mm cover over reinforcement. Curing is crucial, especially in hot or windy conditions, by spraying water or using a curing compound such as Mapecure E, Mapecure S, or Elastocolor Primer.
Mapegrout T40 is chosen for its specific properties in challenging concrete repair scenarios:
In a complete concrete repair system, Mapegrout T40 typically follows the preparation and corrosion protection steps. First, ensure the concrete substrate is clean, sound, rough, and saturated, with exposed reinforcing bars treated with an anti-corrosion primer like Mapefer or Mapefer 1K. Mapegrout T40 is then applied to rebuild the concrete section. Post-application, internal curing with Mapecure SRA and external curing with water or a curing compound are essential to prevent plastic shrinkage cracks. For a complete protective system, the repaired surface can be skimmed with products like Monofinish or Mapelastic, then coated with Elastocolor Paint.
Mapegrout T40 is designed for R3 structural concrete repairs requiring medium mechanical performance, such as repairing degraded vertical or overhead surfaces. It provides 40 MPa compressive strength after 28 days and meets EN 1504-3 R3 standards, ensuring reliability for structural applications.
Yes, Mapegrout T40 is a thixotropic mortar that can be applied by trowel or spray in thicknesses up to 30 to 35 mm per layer on vertical and overhead surfaces without formwork. This capability simplifies repairs in challenging locations like balcony edges or beam corners.
Before applying Mapegrout T40, all degraded concrete must be removed, and reinforcing bars must be sandblasted clean of rust. Rebar must then be treated with Mapefer or Mapefer 1K for corrosion protection to ensure proper adhesion and long-term durability of the repair.
No. Mapegrout T40 is not for structures under high compressive loads, impact, or abrasion; use Mapegrout Thixotropic or Mapegrout T60 for those. It is also not for anchoring or for pumping into formwork. Always ensure the concrete surface is thoroughly roughened before application.
| Application | Key benefit | Primary trades |
|---|---|---|
| Repair of degraded concrete elements like pillars, beams, and balcony corners | Restores structural integrity with 40 MPa compressive strength, meeting EN 1504-3 R3 for structural repair. | Concrete restorers, structural engineers |
| Reconstruction of concrete covering for rusted reinforcing bars | Provides a durable, shrinkage-compensated repair that adheres strongly to treated rebar, preventing future corrosion. | Civil contractors, heritage restorers |
| Repairs to diaphragms, tunnels, and hydraulic structures | Offers waterproof, R3-compliant repair material that can be spray applied for efficient coverage and meets AS/NZS 4020 for potable water contact. | Civil engineers, infrastructure maintenance |
| Filling rigid joints and surface irregularities on concrete | Forms an easy-to-apply thixotropic mortar that holds without formwork, ideal for precise infill and surface restoration. | Builders, facade specialists |
Prepare the mix using a low-speed mechanical mixer. Do not mix by hand.
Trowel Application: Use 3.8 to 4.0 litres of clean water. Spray Application: Use 3.9 to 4.1 litres of clean water.
Add the required water to the mixer first. Slowly add the 25 kg bag of Mapegrout T40 while mixing. Mix for 1-2 minutes, scrape down the sides and bottom of the mixer, and then mix for another 2-3 minutes until a completely homogenous, thixotropic paste is formed.
Apply the mortar to the prepared, Saturated Surface Dry (SSD) substrate.
Apply with a trowel or gauging trowel. The thixotropic mix allows application on vertical surfaces or ceilings in thicknesses up to 30-35 mm per layer without formwork.
Spray apply using suitable equipment (e.g., Turbosol, Putzmeister). This is ideal for large vertical surface repairs.
Proper curing is critical to prevent surface cracks from rapid water evaporation, especially in hot or windy conditions.
Spray water on the surface 8-12 hours after application. Repeat this process every 3-4 hours for at least the first 48 hours.
Alternatively, apply a curing compound like Mapecure E, Mapecure S, or Elastocolor Primer with a low-pressure pump after tamping the mortar.
Danger: Causes skin irritation. May cause an allergic skin reaction. Causes serious eye damage. May cause respiratory irritation.
Wear close fitting safety goggles; do not use eye lenses. Wear clothing that provides comprehensive skin protection, such as cotton, rubber, PVC, or viton. Use protective gloves, with nitrile gloves (1.3 mm, 480 min breakthrough) suggested, or polychloroprene, butyl rubber, or fluorinated rubber options.
Use only outdoors or in a well-ventilated area. Use localized ventilation system to avoid inhalation of dusts and mists.
Store in a well-ventilated place, keeping the container tightly closed. Keep away from food, drink, and feed. Dispose of contents and containers in accordance with applicable regulations. Do not allow product to enter drains or waterways.
Proper substrate preparation is critical for Mapegrout T40 to achieve its documented mechanical strengths and adhesion, preventing premature failure of the repair.
Surface prep: Remove all degraded and loose concrete until a solid, resistant, and rough substrate is exposed. Any previous repair materials that are not fully bonded must be removed. Sandblast the concrete and any reinforcing bars to remove dirt, rust, cement laitance, grease, oil, varnish, or old paint. Saturate the concrete with water, then wait for excess water to evaporate. Use compressed air if needed to eliminate free water before application.
Primer: Not required for the concrete itself. However, reinforcing bars must be treated with Mapefer or Mapefer 1K before Mapegrout T40 application to prevent corrosion and ensure bond.
| Property | Value |
|---|---|
| Class According To EN 1504-3 | R3 |
| Type | PCC |
| Consistency | powder |
| Colour | grey |
| Maximum Aggregate Size | 2.5 mm |
| Bulk Density | 1250 kg/m³ |
| Dry Solids Content | 100 % |
| Chloride Ions Content (according to EN 1015-17) | ≤0.05 % |
| Colour Of Mix | grey |
| Mixing Ratio | 100 parts of Mapegrout T40 with 15.5-16.5 parts water (approx. 3.8-4.1 l per 25 kg sack) |
| Consistency Of The Mix | thixotropic |
| Density Of The Mix | 2200 kg/m³ |
| pH Of The Mix | > 12.5 |
| Application Temperature Range | from +5°C to +35°C |
| Pot Life Of The Mix (at +20°C) | approx. 1 hour |
| Compressive Strength (1 day) | > 8 MPa |
| Compressive Strength (7 days) | > 30 MPa |
| Compressive Strength (28 days) | > 40 MPa |
| Flexural Strength (1 day) | > 2.0 MPa |
| Flexural Strength (7 days) | > 5.5 MPa |
| Flexural Strength (28 days) | > 7.0 MPa |
| Compressive Modulus Of Elasticity (28 days) | 25 GPa |
| Bond Strength To Concrete (28 days) | > 2 MPa |
| Capillary Absorption | < 0.20 kg/m²·h^0.5 |
| Thermal Compatibility (freeze-thaw cycles) | > 1.5 MPa |
| Thermal Compatibility (storm cycle) | > 1.5 MPa |
| Thermal Compatibility (dry thermal cycle) | > 1.5 MPa |
| Reaction To Fire | A1 (Euroclass) |
| Consumption | 18.5 kg/m² per cm of thickness |
Here are some common examples on where Mapei Mapegrout T40 Mortar used by our customers.
