CONCRETE POURING IN RAIN
CONCRETE POURING:- Water is a major component of all concrete.
which is mixed with cement and causes it to hydrate and regain strength.
After concrete is laid water can do more harm than good as driving rain.
Pouring concrete in the rain can compromise its strength, leading to increased tendency to dust and scaling.
Once damage is done. it can be difficult to fix and will often ruin the appearance of the finished surface. Do not let it rain on your parade.
Here are some tips to prevent and prevent rain-damaged concrete.
Advice for pouring concrete in the rain
Despite modern weather forecasting techniques and radar maps,
an unexpected rain shower can develop without warning, especially during the hottest months of the year.
If rain is in the forecast, you should postpone pouring a large concrete until conditions improve.
Even if rain is not predicted you should always be prepared to cover concrete with tarp or plastic wrap just in case.
Be sure to seal the edges so that rain water does not fall down.
Looking for the presence and location of gutters and downspots, scope the jobsite before the project even starts.
Rainwater coming down from the edge of the roof without a gutter or waterfall will dig a moat into the wet concrete if the slab is directly below the overflow.
Tips for handling rain after concrete pouring
Here's how to react if it lays down on your freshly placed concrete:
Do not bring the rain water to the concrete surface, this is your biggest mistake.
Do not transmit dry cement on concrete to absorb surface water.
This will deteriorate the finish and further weaken the top layer.
Instead, once the rain has passed, use a float before pushing the water from the side of the slab.
How long does it take for the concrete pouring to dry before the rain?
Even if it starts raining after pouring concrete, the chances of damage are not as severe.
If you have time to complete the finishing process and the concrete has hardened (usually 4 to 8 hours after mixing), rainwater can cause little damage.
In fact, once the solid is set, water on the surface is actually beneficial as it aids in hydration and curing.
A simple scratch test, using a screwdriver or a Mohs concrete surface hardness scratch test kit, can be performed to assess the integrity of the surface and to determine if there was any effect of the rain.
Solutions for Rain-Damaged Concrete
Surface scaling, or spalling, as seen on this stamped concrete can be caused by the weakening of the concrete's surface strength during or immediately after rain.
If the worst happens and the sky opens up on your fresh-to-the-truck concrete,
it is a good bet that rain will wash away some of the cement from the concrete on the surface.
This is likely to cause problems such as:
Dusting
Surface scaling
Craze cracking (easily stimulated by freeze-melt cycles)
If the concrete is integrally colored, then some colors may also wash away and draw streaks due to rain on a rainy day.
Short of ripping and starting the concrete, the best solution is to remove the weakened surface layer by grinding and
then re-wake the concrete with an overlay, after ensuring that the underlying concrete is structurally sound.
Other problems with rain
Before you lay the concrete slab, rain can have a damaging effect if it oversets the suburb and causes pinging.
This is because excess water can be absorbed by fresh concrete and change the water-cement ratio.
If it rains a day or two before the rain, cover the ground with plastic wrap to keep it from becoming saturated.
Rain can also wreak havoc on freshly sealed concrete, causing sealer bubbles and blistering.
Be sure to apply the seal when it remains rain-free for 24 hours after sealing.
Comments
Post a Comment