What is the pH of water for concrete?

While the use of potable water is generally safe, water not fit for drinking may also be satisfactorily used in making concrete. As a rule, any water with pH of 6.0 to 8.0 which does not taste saline or brackish is suitable for use.

What is the pH of cured concrete?

In new cured concrete, it is expected to find a pH 11 – pH 13.5 with the norm being somewhere around pH of 12.5 this is normal and should be.

Does concrete change the pH of water?

When concrete structures—such as pier supports—are placed in water, they can have a detrimental effect on the surrounding environment by causing the pH to rise.

Which water is used for curing concrete?

We want to use river water to cure concrete for an elevated structural slab at a train station. The river water normally contains 100 parts per million (ppm) of salt but occasionally tests at 1,000 ppm.

Is concrete acidic or alkaline?

Concrete is alkaline in nature, meaning it has a pH of 7.0 or above. It gets its high pH from several ingredients containing calcium.

What is pH value of concrete is it acidic or alkaline?

pH and Its Affect on Concrete. A neutral pH is 7, which is what you find in natural freshwater. Anything above 7 is alkaline, and anything below is acidic. Portland cement, concrete’s binding agent, has a pH of 11, making it alkaline.

What should be the pH value of water for construction work?

Following criteria should be followed in order to assess the suitability of water for construction: The pH value of water shall be not less than 6. To neutralize 100 ml sample of water, using phenolphthalein as an indicator, it should not require more than 5 ml of 0.02 normal NaOH.

Does concrete have a low pH?

Concrete Starts Out With a High pH Value As pH values drop below 7, something will become more acidic. Likewise, as pH values climb up above 7, they become more basic. Fresh concrete has a surprisingly high pH value of around 13 – in other words, nearly at the top of the scale.

What is alkaline concrete?

The reaction between alkaline pore solution (OH-, Na+ and K+ ions) and reactive silica in the aggregates produce a reaction product called alkali-silica gel. If this gel absorbs sufficient moisture, it expands, creating internal pressures in the concrete, which can exceed the tensile strength and crack the concrete.