Construction project managers come across varied issues when it comes to concrete construction on multi-story car parks. Curing the concrete in particular can be pressuring for the site team, since access issues, disruption to trades, and non-compatible coatings all incur more downtime and expenses on the project.
The takeaways of this article can be applied to any concrete structure, but would be especially useful on projects where:
– upper levels cause water availability to be limited onsite
– compatible curing is an important consideration, and
– the end use is for vehicular traffic.
Give yourself 6 minutes to read!
- Water access
- Compatibility and final appearance
- Our recommendation
- Staying as is
- Addressing Construction requirements and Long-term use
Curing the slab – water access.
Where water access is limited onsite, some standard curing methods (such as water curing) are not so do-able as ground-level construction.
Water curing comes with a constant need to keep the slab moist – this can be hard to keep up with.
Laying blanket coverings to keep the water from evaporating is a step ahead – this requires less attention, but it can take a while to lay blankets in a large area, and again requires a substantial amount of water at the start.
Likewise, any chance to avoid curing compounds that are required to sit a while on the surface of the slab is welcomed by many site teams; if in use, care must be taken by all trades not to enter the area, lest walking on the treated slab they track the substance on to other areas of the site and leave residue that can only be ground off (often a milky white coating). So this tends to be disruptive in an area where access for other trades needs to be available.
Compatibility and final appearance.
If visual appearance of the concrete is important, the film should be removed after curing. Some compounds dry leaving a coloured or white surface, sometimes blotchy across the slab, and crazing as it goes hard. Film-forming curing and hardening compounds typically require a grind for removal – certain compounds dissipate after 28 days, but even this can take too long.
Where further coatings are required, the paint may also not be compatible with the curing or hardening agent; in this case, grinding off specific areas for line-marking or floor paints to be applied can multiply the time and cost involved.
With these factors in mind, the project manager of a car park construction will be very conscious of the time factor, with most methods of curing concrete taking up a lot of space in the construction schedule.
And yet, the curing process mustn’t be left out – even the smallest of concrete pours prove the value long-term of having an effective cure. The compressive strength of concrete moist-cured after 7 days is 1.5x that of concrete that is not given attention to curing – the strength of cured concrete continues to increase, as well.
The immediate need is for a system that allows the critical process of curing to happen in the least possible time, in the way of as few trades as possible, but accepted by the entire team so that it can be used over and over again with no question or holdup.
We recommend having a systemised approach that is a simple process to put into place.
Find a trusted contractor who you know can complete the job and do it with the project-specific challenges in mind, rather than needing to find a subcontractor to do the works each time, or requesting the concreter to complete it as they go. This is so that various and unexpected issues such as access and compatibility don’t hinder the project – you should be able to turn to this contractor for any project, knowing they will be able to complete the works well as a result.
Unhindered supply is another factor to having a systemised approach – a sure supply of the necessary product will mean that risk of holdup is lower, and substandard products are not used as a stop-gap measure.
It’s possible to have these two aspects dealt with in one hit – a single supplier and installer, who can be relied on to have the means to complete the job every time, and with less difficulties for future trades – they may even cover their works with a project-specific warranty, providing assurance of lower risk of works.
Staying as is…
If any of the earlier methods of concrete curing are you or your company’s go-to, because of custom, ease-of-use, or price, it may seem unneeded to consider changing – this could result in a missed opportunity of time and cost saving for the company and project, though.
Using a system of curing that involves flexibility with site-access, and easier, faster application – this in turn results in lower downtime both in the process, and in the construction of the building.
We’d like to offer a method of curing that is supplied and installed by a single contractor, and warranted by the same, that consists of simple treatment, rapid clean-up if necessary, and QA conducted by the team onsite and reviewed by the Operations team in the office.
This method of curing and sealing with a systemised contractor has seen use on numerous multi-level car parks, where faster curing timeframe and accessibility has been valued by the site manager and building team. If the right system is used, you can even avoid the tyre squeal and slippage disliked by car park users and building tenants.
A single system such as INFRA-TECT, used on car parks during curing stage – even retro-applied! – will ensure that obstacles identified during construction can be overcome at the same time as proactively protecting the car park for the years of wear to come.
Addressing Construction requirements and Long-term use
Combine your immediate needs during construction with the long-term requirements of car parks exposed to the elements!
What we would like to show is that proactive protection to increase concrete durability can be done at the same time as you meet the curing specifications, with a single system, supplied and applied by one contractor.
What goes on in car park concrete over time could be likened to concrete in harsh conditions such as marine environments or acidic areas – abrasion from tyres, and contamination from exhaust fumes both shorten the life span of the concrete in the structure.
So to ensure maximum service life from Day 1, these aspects need to be taken on board as well. It can prevent the need for the asset owner to get into an early and ever-tightening maintenance cycle.
It’s worth choosing the complete system – INFRA-TECT – to meet your specifications on the next project. It is implemented quickly onsite, and the area can be returned to use without risk of mess or defect quickly after application.
It makes for easier car park concrete construction, with less issues of compatibility or access.
The downloadable information is available in the document library below – have a look through and consider using this time-saving system on your next project!
Got a specific project challenge? Get in touch!
(Top image: Northern Hospital multi-level car park, Epping VIC)