Rehabilitation, restoration and levelling of garage

Descripción sistema

Garages are subject to heavy wear and tear due to the constant passage of vehicles. Ramps and curves are often damaged, creating potholes in the screed mortar or concrete. There are many buildings where the paving was not given the proper importance and were made with concrete screeds poor in cement and screed mortars with low modulus of elasticity to avoid cracking, but this has made them especially sensitive to wear and tear and detachment with vehicle traffic.

This article describes the restoration of a screed mortar and concrete pavement by replacing the screed layer with a high performance self-levelling product suitable to withstand the passage of vehicles at relatively low thicknesses (from 8 mm). The executed solution consists of the application of BETOLEVEL® 30 with an adequate preparation of the substrate and bonding bridge, together with a good joint layout, suitable for the existing vibrations and substrate.

Reason for the intervention

Rehabilitation, restoration and levelling of pavement for vehicular traffic.

Challenges and constraints

“The garage is a floor slab and is therefore subject to vibrational movements due to the passage of vehicles.
“The screed mortar has low strength and is detached from the concrete base of the slab.
“The concrete screed has low strength.
“It is not advisable to add weight to the structure, so high thicknesses are ruled out.
“A fluid mortar is required that works at low thickness and has a smooth finish for protection with epoxy paint.

Molins Solution

Remove all the screed mortar not adhering to the base layer concrete, until a stable substrate is reached, removing dust by sweeping and vacuuming loose particles. Place 1 cm polystyrene sheet around the contour of pillars and walls to create a perimeter joint.

Application of primer and humidity regulator
for porous surfaces PROPAM® PRIMER SOL prior to screeding and self-levelling with BETOLEVEL® 30, with the possibility of two applications in the case of screeds greater than 3 cm. This self-levelling product is suitable for vehicle traffic at thicknesses greater than 8 mm.

For extreme cases on site with higher vibration and adhesion requirements, make perimeter joints and partition joints per parking space (approx. 7.5 m2 panels) and adhere with PROPAM® GRIP + surface consolidating bonding bridge. Finish with epoxy paint against abrasion BETOPOX® 92 AR with BETOPOX® PRIMER as primer.

Execution

“The affected areas were cut and the unbonded mortar was removed down to the base plate, and the surface was swept and vacuumed.

“In the areas most damaged by lack of resistance and subjected to vibrations, the universal adhesion bridge was applied, acting in this case as a surface consolidator, PROPAM® GRIP + , in the rest of the consolidated pavement and only as a moisture regulating primer, given its great porosity and irregularity, the product PROPAM® PRIMER SOL was applied.

“3. A barrier foil was placed as a barrier to establish the perimeter joint.

“The product BETOLEVEL® 30 is brought as close as possible because the kneading is carried out in a bucket by means of an electric drill from bag to bag and water as indicated in the technical data sheet.

” 5. The BETOLEVEL® 30 self-levelling fluid product is then spread over the surface, using a strip with a handle to adjust it to the desired level and to even out the sacks that are gradually poured in.

“6. The following day, after less than 24 hours, the partition cuts were made, marking where it had been planned and then the cuts were made, the shortest sections were in the area that we indicated as the most affected, cutting along the line of the squares to better allow the expansion and possible vibration of the plate.

“After 3 days, an epoxy paint finish was applied to increase durability and to match the surface finish with the rest of the pavement.

Technical note

In order to lay a cementitious self-levelling floor covering correctly, the following 5 key aspects must be taken into account. The substrate must be properly prepared, it must be stable, free of dust and grease, we will select the appropriate primer for the substrate, whether it is very or slightly porous, we will design a good arrangement of joints that will be vital for the success of the flooring (perimeter, expansion, fractionation), it will also be important to choose the self-levelling according to need, whether it is for building or industrial areas and finally the application will be correct according to the product’s technical data sheet.

David Rodriguez (technical office)