Concrete is present in many construction projects focused on a stable and strong structure. However, weather can play a vital role when the solidness of this material comes to mind, but also its durability. With the climate changes, concrete may suffer adverse effects on its solidness and durability – especially in the colder days.
The definition of cold for concrete is any temperature less than 40 F lasting for at least three days. Simply because the cement mixture transforms to solid through a series of chemical reactions, it is up to the current temperature at the moment to determine how fast the material will dry. Furthermore, if the weather is warm, the drying will be fast. But if the temperatures are low – it may trigger the water to freeze which results in the material breaking apart in pieces.
The liquid form of concrete, in fact the mixture – must be the one that is maintained within the temperature range from 50 F to 75 F so that it prevents becoming concrete. Additionally, if concrete is not cured properly it can result with a shorter lifespan, an optimal strength against weather conditions and ultimately, cracking. After the phase of layering the concrete finishes, the pouring process should start.
Curing concrete refers to keeping the concrete aprons, driveways and curb repairs wet for at least three days to prevent them from transforming into solid materials. The best way to do this is either by using sprinklers and hoses or by covering the area with plastic to hold and prevent the water from drying. However, if the temperatures are freezing – straw is one of the bet solutions in order to insulate the slabs.
During the snowy winter when it is very cold, concrete should never be poured simply because of the freezing effects it may result with. That is why using curing blankets for concrete is probably the best way in freezing conditions, however there are many anti-freeze mixtures that can be added to the layer to prevent it from freezing. Warming up the concrete so it resists the cold temperature and for it to dry in the best way possible is essential for every concrete driveway installation or renovation.
On the other side, when the weather is extremely hot, concrete can dry with lots of cracks, again resulting with damage. That is why pouring the coolest part of the day or night should be reserved for pouring concrete – simply because of the evaporation which is lower in these times. Additionally, special windbreaks and sunshades should be utilized in order to control the temperature of the concrete surface and result with pouring done in the right way during extreme weather.
During the winter, the extensive freeze-thaw conditions may be the force that spalls and scales concrete. However, with the proper mix design, placement and curing concrete in the right way – long-term durability can be ensured.
The primary considerations when curing concrete are focused on using blankets for heat retention, just because of the natural power of concrete to warm itself. Curing concrete in the winter can also adopt some chemical strategies as well as using solvent-based curing compounds or cure-and-seat chemicals. In general, proper planning and communication are the main prerequisites for a successful concrete winter pour.
Obviously, pouring concrete is not an easy job in extreme temperatures. It is a job that uses a special equipment for it to be applied correctly, which may include but is not limited to:
non-water-based curing compounds
sprayers to apply the curing compounds
proper cold-weather attire for the crew pouring and finishing the concrete
concrete pumps to speed up the placement in cold conditions
ground heaters if the ground is frozen before the pouring occurs
Spring – Although spring is very short in Minnesota, proper concrete installment or renovation can be completed successfully. With the threat of snow and freezing temperatures gone, the only consideration during spring which may affect concrete badly is rain. During spring, the best way to set concrete quickly and uniformly is to use chemical set accelerators as well as special curing practices such as plastic sheeting, surface evaporative control agents etc.
Summer – The hot and humid summer requires a special use of admixtures to extend the set time. Therefore, hydration stabilizers and water reducers are a common choice when installing concrete and making sure of its proper durability. In these hot and humid days, the best way to finish an exterior concrete project is to do a quick placement with plastic sheeting to prevent the concrete from any sudden rainfall and sprayers to apply the evaporative control chemicals.
Fall – Fall may be the most stable weather condition for pouring exterior concrete. With a low humidity and warm days with cool nights, the placement and curing practices on concrete should also include the use of curing compounds and cure-and-seal chemicals with special blankets.
Winter – We already talked about the special treatment of concrete in winter above, with all the equipment needed and the recommended way to pour and cure concrete accordingly.
In the end, what you should know about curing and pouring concrete in Minnesota is that the main factor is the free water to cement ratio. If it is low, you will struggle to get it to compact properly which may result in air voids and weak concrete. On the contrary, if the water content is too high, it will leave pores in the concrete which may reduce the strength and durability.
Undoubtedly, a professional concrete installation or renovation is what every home and business owner needs in Minnesota in order to treat the risky concrete materials on the exterior in the right way. For more information on our concrete installation, renovation, repair and other services, you can contact our team at Minnesota Concrete directly and get a free estimate.