Repair of entrance ramps to the Sant Antoni market car park.

Descripción sistema

The Mercat de Sant Antoni is one of the most important markets in Barcelona. It was built at the beginning of 1879 and completed in September 1882.

It is the only market that is open seven days a week. In addition to the sale of fresh food, the encantes (market of all kinds of materials) and on Sundays bookshops, collectors of all kinds meet in this market.

In 2007, renovation work began, but it was in 2009 when the old market was definitively closed to begin the remodelling of the new market, which was completed in 2018, due to the fact that the work was delayed by the discovery of archaeo-logical remains belonging to the Roman Via Augusta, a necropolis and the remains of the Sant Antoni Bastion.

In this reform, in order to accommodate all its activity, four underground floors were built for goods and parking.

Reason for the intervention

The high level of activity concentrated in the market, the entry and exit of both goods and private vehicles, has led to wear and tear and deterioration of the access ramps to the car park.

This deterioration has resulted in small potholes and chipping, especially in the area where the wheels of the vehicles pass, causing problems in the movement of the lorries’ loads, as well as discomfort for car park users.

To avoid such discomfort, and to make vehicle entry safer, the two access ramps have been repaired with a polyurethane coating, with anti-slip treatment.

Challenges and constraints

“The need to find a fast application system, with very resistant materials, given the daily traffic to which the repaired ramps are subjected.
“Since this is a period of the year when it is likely to rain, the application and drying process of the materials used must be fast.
“Due to the daily activity of the market, access to the car park had to be regulated, as it could not be closed while the work was being carried out.

Molins Solution

“Thorough cleaning and preparation of the substrate by sanding and, if necessary, shot-blasting of the ramps and subsequent vacuuming of the ramps.
“Application of epoxy primer BETOPOX® 896, dusting of aggregate (0.4-0.9 mm) to saturation.
“Sweeping and vacuuming of the remaining aggregate and application of BETOPOL® polyurethane coating (grey colour) and new dusting of aggregate, to achieve an optimum anti-slip level.
“Sweeping, vacuuming and application of finishing coat with BETOPOL (grey colour).

Execution

Preparation of the support:

“First of all, the work was planned to prioritise the activity of both goods and customers entering the car park floors. To do this, the first ramp to be worked on had to be closed, installing traffic lights to regulate the incoming and outgoing traffic.
“2. Subsequently, all the areas of the previous covering that were unglued or poorly adhered were checked and eliminated, until the support was sufficiently resistant.

“The entire surface was then thoroughly sanded and vacuumed to obtain an open-pored surface, completely free of dust and loose particles from the previous flooring.

The Molins Multilayer System was then applied:

” BETOPOX® 896, a low viscosity, 100% solids, transparent epoxy primer of 350 gr/m2, was applied by roller to achieve perfect adherence of the system to the substrate. While the primer was still fresh, up to 90 minutes approximately and always depending on the environmental conditions, a first dusting of quartz aggregate, size 0.4-0.9 mm, with an approximate consumption of 1 kg/m2, was applied until the primer was saturated.

BETOPOX® 896 is supplied in pre-dosed 2-component sets. Partial mixing is never recommended as the mixing ratio is strict. For mixing, the contents of component B (hardener) were poured into the container of component A (resin) and both components were mixed with the aid of a low speed mechanical agitator (<400 r.p.m.) ensuring that the agitator reached the sides and bottom of the container and taking care not to incorporate air into the mixture, until both components were completely homogenised.

The pot life of the mixture is approx. 35 min, so the sets were mixed as they were applied.

“2. This was followed by sanding. After 24 hours, sweeping and vacuuming was carried out to remove all unbonded aggregate particles.
“3. Then, to guarantee an optimum degree of slipperiness of the pavement, a second coat of BETOPOL was applied, with an approximate dosage of 250 g/m2, and a dusting of quartz aggregate (0.4-0.9 mm.) was applied until saturation.
“4. The following day, the pavement was swept and vacuumed again. The following day, the pavement was swept and vacuumed again, in order to remove any remaining aggregate that had not adhered properly in the previous stage, and to ensure the cohesion of the entire system.

” 5. Once this application had been made on the pavement, a finishing coat of BETOPOL was applied, a two-component pigmented aliphatic polyurethane coating with high resistance to abrasion, with an approximate consumption of 200 g/m2. Firstly, it was applied in those singular points (corners and areas of difficult accessibility), and then a first coat of the final coating was applied.

“6. Finally, the following day, a final coat with BETOPOL was applied.

Technical note

Slipperiness classification

Slipperiness is the characteristic of flooring given by the possibility of the user slipping or sliding due to the surface constitution of the flooring.

The Basic Document DB SUA-1 of the CTE establishes the requirement to avoid the risk of slipping on floors in buildings or areas for Public Residential, Health, Educational, Commercial, Administrative and Public Concurrence use, excluding areas of zero occupancy, which are defined in Annex SI A of the DB SI.

For this purpose, the following classification table must be complied with, which is required for flooring depending on its use.

The sample selected shall be representative of the most unfavourable slippery conditions.

(1) Except for direct access to restricted areas.
(2) In areas intended for barefoot users and at the bottom of pools, in areas where the depth does not exceed 1.5m.