Concrete Repair Mortars

Sika Monotop 612 Concrete Repair Mortar

Hand placed / Wet Spare Mortar Microconcrete

Product Description:

Sika® MonoTop-612 is a cement-based, one component low permeability repair microconcrete, containing silica fume and polymer.


Uses:

  • For repairing all types of structures
  • Horizontal, vertical and overhead repairs
  • Hand applied repairs
  • Spray applied repairs
  • For exterior and interior use

Characteristics /Advantages:

  • Pre bagged for quality
  • Compatible with Sika FerroGard corrosion inhibitors
  • Easy to mix and apply
  • Low shrinkage
  • Good mechanical properties
  • Adjustable consistency
  • Suitable for drinking water contact

Tests:

Approval / Standards Resistivity: Mott MacDonald Report No. 37423/DA/001.Rev A

Product Data:

Form:
Appearance /Colours Grey powder
Packaging 25 kg bag

Storage:
Storage Conditions/

Shelf-Life:
6 months from date of production if stored properly in original unopened, sealed and undamaged packaging in dry and cool conditions.

Technical Data:

  • Chemical Base Portland cement, polymer redispersable powder, selected aggregates and additives
  • Density Fresh mortar density: ~ 2.10 kg/l
  • Grading Dmax: 3 mm
  • Layer Thickness 5.0 mm min. / 30 mm max.
  • Change of Volume Drying Shrinkage 0.04% (mean) (BS 6073 :Pt1 :1981)
  • Thermal Expansion Coefficient 12.0 x 10-6 m/m °C

Mechanical / Physical Properties:

  • Compressive Strength 1 day ~ 15-20 N/mm2. 28 days ~ 45-55 N/mm2
  • Flexural Tensile Strength 28 days ~ 7-9 N/mm2
  • Tensile Adhesive Strength ~ 1.5-2.5 N/mm2 (substrate failure with Bonding Primer)
  • E-Modulus 25 kN/mm2 (static)

Resistance:
Resistivity (kohm.cm)
RH% Resistivity
100 46
81 90
65 136
44 176

System Information:

  • System Structure Sika® MonoTop-612 is part of the Sika® MonoTop Concrete Repair System
  • Sika® MonoTop-610: Bonding primer and reinforcement coating
  • Sika® MonoTop-612: Hand and wet spray applied repair mortar
  • Sika® MonoTop-615: Hand and wet spray applied high build repair mortar
  • Sika® MonoTop-620: Smoothing coat
  • Sika® FerroGard®-903: Corrosion inhibitor

Application Details:

Consumption This depends on the substrate roughness and thickness of layer applied. As a guide, ~ 2.11 kg/m2/mm.

Substrate Quality Concrete:

The concrete shall be free from dust, loose material, surface contamination and materials which reduce bond or prevent suction or wetting by repair materials.

Steel reinforcement:

Rust, scale, mortar, concrete, dust and other loose and deleterious material which reduces bond or contributes to corrosion shall be removed to a minimum standard of SA2½. Reference should also be made to BS EN1504-10:2003 for specific requirements.

Substrate Preparation / Bonding Primer / Reinforcement Coating Concrete:

Delaminated, weak, damaged and deteriorated concrete and where necessary sound concrete shall be removed by suitable mechanical or very high pressure waterblasting [up to 110 mPa (16500 psi)] techniques. Tying wire fragments, nails and other metal debris embedded in the concrete should be removed where possible. The edges where concrete is removed should be cut at a minimum angle of 90o to avoid undercutting and a maximum angle of 135o to reduce the possibility of debonding with the top surface of the adjacent sound concrete and should be roughened sufficiently to provide a mechanical key between the original material and Sika® MonoTop-612.

Ensure sufficient concrete is removed from around reinforcement to allow coating and compaction of the repair material.

Steel reinforcement:

Surfaces should be prepared using abrasive blast cleaning techniques or high pressure waterblasting [up to 60 mPa (9000 psi)] techniques. Where exposed reinforcement is contaminated with chloride or other material which may cause corrosion, the reinforcement shall be cleaned by low pressure waterblasting [up to 18 mPa (2700 psi)].

Bonding primer:

On a well prepared and roughened substrate a bonding primer is generally not required. When a bonding primer is not required pre-wet the surface. The surface should not be allowed to dry before application of the concrete repair mortar. The surface should achieve a dark matt appearance without glistening and surface pores and pits should not contain water. When a bonding primer is necessary apply Sika® MonoTop-610 or SikaTop®

Armatec-110 EpoCem® (Refer to the relevant Product Data Sheets). Site adhesion values - Structural Repair 1.2-1.5 mPa Non Structural repairs minimum value 0.7 mPa

Reinforcement coating:

Where a reinforcement coating is required as a barrier, apply to the whole exposed circumference two coats of Sika® MonoTop-610. (Refer to the relevant Product Data Sheet).
Reference should also be made to BS EN1504-10:2003 for specific requirements.
Application Conditions / Limitations
Substrate Temperature +5°C min. / +30°C max. Air Temperature +5°C min. / +30°C max.

Application Instructions:

Mixing Wet Spray Application : 2.5 to 3.5 L of water for 25kg powder Hand Application: ~ 2.5 to 2.7 L of water for 25 kg powder

Mixing Time Sika® MonoTop-612 can be mixed with a slow speed (< 500 rpm) electric drill mixer.

In small quantities only, product can also be mixed by hand. Pour the water in the correct proportion into a suitable mixing container. While stirring slowly, add the powder to the water. Mix thoroughly for at least 3 minutes to the required consistency.

Application Method / Tools:

Hand Applied:
If a bonding primer has been used apply repair mortar “wet on wet”. The repair mortar shall be worked into the prepared pre-wetted substrate between the minimum and maximum layer thicknesses and shall be compacted without inclusion of entrapped air pockets using a trowel or gloved hand. Where layers are to be built up to prevent sagging or slumping, each layer should be allowed to stiffen before applying subsequent layers “wet on wet”. When layers cannot be applied “wet on wet”, or if more than 24 hours between layers elapses apply a bonding primer of Sika® MonoTop-610 or SikaTop® Armatec-110 EpoCem® and apply repair mortar “wet on wet”.

Sprayed application:
The repair mortar shall be placed onto the pre-wetted substrate between the minimum and maximum layer thicknesses without the formation of voids and loose rebound material. Where layers are to be built up to prevent sagging or slumping, each layer should be allowed to stiffen before applying subsequent layers “wet on wet”. When layers cannot be applied “wet on wet”, or if more than 24 hours between layers apply a bonding primer of Sika® MonoTop-610 or SikaTop® Armatec-110 EpoCem® and apply repair mortar “wet on wet”. Finishing for both hand and spray application should be done to the required surface texture as soon as mortar has started to stiffen. Reference shall be made to BS EN1504-10:2003 for specific requirements.

Cleaning of Tools Clean all tools and application equipment with water immediately after use. Hardened/cured material can only be mechanically removed.

Potlife ~ 30-50 minutes (at +23°C)

Notes on Application /Limitations:

Avoid application in direct sun and/or strong wind and/or rain. Do not add water over recommended dosage.

Apply only to sound, prepared substrates. Do not add additional water during the surface finishing as this will cause discoloration and cracking. Protect freshly applied material from freezing.

Curing Details:

Curing Treatment It is essential to cure the repair mortar immediately after application for a minimum of 3 days to ensure full cement hydration and to minimise cracking. Use polythene sheeting taped down at the edges or other approved method. Curing compounds shall not be used when they adversely affect subsequently applied products and systems. Reference shall also be made to BS EN1504-10:2003 for specific requirements.

Value Base All technical data stated in this Product Data Sheet are based on laboratory tests.
Actual measured data may vary due to circumstances beyond our control.

Local Restrictions Please note that as a result of specific local regulations the performance of this product may vary from country to country. Please consult the local Product Data Sheet for the exact description of the application fields.

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12 Fenlake Business Centre, Fengate, Peterborough , PE1 5BQ

01733 560362

sales@concreterenovations.co.uk

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