Solvent-free, Abrasion-Resistant, High-Strength Reinstatement Mortar.

epidermix 520 is a solvent-free, three-component epoxy mortar, formulated to exhibit good abrasion resistance, chemically resistant and high strength characteristics.

  • For repairs to concrete in acid tanks, sea walls and industrial floors.
  • For bedding in precast elements.
  • High early strength ensures limited impact on construction programs or maintenance shutdowns.
  • The high ultimate strength makes it suitable for structural repair use.
  • High resistance to abrasion.
  • Good chemical resistance to a wide range of corrosive materials.
  • Highly impermeable.
  • Will cure under damp conditions.
Surface Preparation

Cleaning of the surface to be repaired is best achieved with a light sand grit blast and/or scabbling to remove all loose material, corrosion products or any other deleterious materials. Contaminants such as oil and grease should be removed by steam cleaning, detergent scrubbing or the use of a proprietary degreaser. Any corroded, exposed steel must be cleaned to a metallic finish and concrete cut back behind the steel to fully expose the back of the bars. See data sheet ‘Preparation of Surfaces’. All repairs to be cut back to a minimum thickness of 5mm to a sawn edge. Minimum application thickness of epidermix 520 is 5mm.

Bonding / Priming

All epoxied re-bar to be coated with dura.®rep ZR primer to give an unbroken finish and allowed to dry.

Horizontal and vertical substrates should be primed using epidermix 326, a two-component epoxy primer. The base and activator components need to be thoroughly mixed for 3 to 5 minutes to achieve a uniform colour and consistency. The mixed primer must be thoroughly applied to the substrate in its horizontal application to avoid puddles of material forming. The primer should be allowed to dry for 30 minutes to release its solvent. The primed surface should be tacky when applying the epidermix 520.

The mixed primer must be thoroughly applied to the substrate in its horizontal application to avoid puddles of material forming.

Typical Physical Properties
Compressive strength (ASTM C109) 68 Mpa at 7 days
Flexural strength 20 Mpa at 7 days
Tensile strengths  (ASTM C307) 9 Mpa at 7 days
Pot life 40 minutes
Initial cure 24 hours
Full cure 7 days
Relative density 2,015

Chemical Resistance

(The low permeability of epidermix 520 retards chemical attack in aggressive environments)
Citric acid 10% Very High
Tartaric acid 10% Very High
Hydrochloric acid 25% Very High
Sodium hydroxide 50% Very High
Diesel fuel/petrol 100% Very High
Sulphuric acid 10% High
Sugar solutions Saturated High
Lactic acid 10% High
Hydrocarbons 100% High
Phosphoric acid 10% High
Nitric acid 10% Medium
Acetic acid 5% Low

Add the entire contents of the activator tin to the base component and, without splashing, stir with a flat paddle until an even streak-free mixture results. This takes at least five minutes by hand.

Once liquid components have been thoroughly mixed, the aggregate may be added. When using a mechanical mixer, place mixed liquid in the pan and slowly add premixed aggregate, mixing until an evenly coated, wetted mortar results. Use this method also if manual mixing is carried out in a drum. If manually mixing on a board, make a heap of the mixed aggregate, form a saucer in the centre of the heap; add the mixed liquid to the saucer. Fold the aggregate into the liquid taking care that no binder is lost. Mix as in mixing cement mortar. All lumps must be broken down and an evenly wetted mortar obtained.


1 litre/m2/1mm thickness.


Tightly pack the mixed epidermix 520 behind any exposed steel with a gloved hand. All other areas have to be applied with a wood float. epidermix 520 can be applied in a single layer up to 50mm thick horizontally and up to 12mm thick vertically.

Thicker sections can be built up in layers by scratching the surface of the first layer and applying a second layer some 8 to 24 hours later.

Should the epidermix 520 begin sagging, it should be immediately removed and a thinner layer applied. A smooth finish can be achieved with a wetted steel float. The minimum thickness of any repair should not be less than 5mm.


Uncured epidermix 520 can be removed from tools with abe® super brush cleaner immediately after use 69210 Rev: 01-05-08 before the material has had time to cure. Hardened material can only be cleaned by mechanical means.


As with all epoxies, the mixture may not be applied to substrates at a temperature lower than 5°C. At ambient temperatures above 35°C, working time and pot life will be drastically shortened.

Model Specification

Three-component, high-build epoxy mortar for fast reinstatement of concrete in vertical and overhead applications where chemical resistance is required. 

The repair mortar will be epidermix 520, a three-component, solvent-free, epoxy mortar applied in accordance with the recommendations of a.b.e.® Construction Chemicals, including dura.®rep ZR primer for steel or epidermix 326 for concrete.


epidermix 520 is supplied in 5 liter yield kits.

Handling & Storage

This product has a shelf life of 12 months if kept in a dry cool place in the original packaging. In more extreme conditions this period might be shortened.

Health & Safety

Wet epidermix 520 is toxic but non-flammable. Ensure the working area is well ventilated during application and drying. Avoid flames in vicinity. Always wear gloves and protective eyewear when working with the material and avoid excessive inhalation and skin contact. If material is splashed in the eye, wash with plenty of clean water and seek medical attention. Curedepidermix 520 is inert and harmless.

Important Note

This data sheet is issued as a guide to the use of the product(s) concerned. Whilst a.b.e.® Construction Chemicals endeavors to ensure that any advice, recommendation, specification or information is accurate and correct, the company cannot – because a.b.e.® has no direct or continuous control over where and how a.b.e.® products are applied – accept any liability either directly or indirectly arising from the use of a.b.e.® products, whether or not in accordance with any advice, specification, recommendation, or information given by the company.

Further Information

Where other products are to be used in conjunction with this material, the relevant technical data sheets should be consulted to determine total requirements. a.b.e.® Construction Chemicals has a wealth of technical and practical experience built up over years in the company’s pursuit of excellence in building and construction technology.