Why Do We Reduce Moisture In Cement Mill

Jul 09, 2020 At a water-cement ratio of 0.50, there is about 300 pounds of water and 600 pounds of cement in a cubic yard. As the concrete begins to set, some of that water (about half) combines with the portland cement (through hydration) and some rises to the surface as bleed water where it evaporates. The rest is in the pores of the concrete

Cement hydration - Understanding Cement

Cement hydration - Understanding Cement

Hydration products. The products of the reaction between cement and water are termed hydration products. In concrete (or mortar or other cementitious materials) there are typically four main types: Calcium silicate hydrate: this is the main reaction product and is the main source of concrete strength. It is often abbreviated, using cement chemists' notation, to C-S-H, the dashes indicating

Get More
MOISTURE CONTENT BY THE OVEN-DRY METHOD

MOISTURE CONTENT BY THE OVEN-DRY METHOD

0.4% moisture content of and oven in a cold dry climate as long as 217 F is used. If the oven temperature is too high, some of the wood components can be driven off. When these are counted as moisture, the indicated moisture content is too high. Do not overload an oven. Good air circulation around the samples is needed to reduce the risk of fire

Get More
Tips on how to prevent surface voids in your concrete

Tips on how to prevent surface voids in your concrete

Air does not mix with water and is not able to get out of the concrete mix, resulting in voids on your concrete surface. Concrete release agents are also a cause for surface voids. When release agents are not applied correctly, the lower ends of the moulds may fill with puddles of oil or the release agent is not designed for the application

Get More
What is the heat of hydration in concrete and how is it

What is the heat of hydration in concrete and how is it

The heat of hydration is the heat generated due to hydration of cement i.e. due to reaction between cement particles and water. It is critical to measure heat of hydration in mass concrete work. As huge volume of concrete is poured in constructing

Get More
What Is Kiln Drying? The Reasoning Behind Drying Wood

What Is Kiln Drying? The Reasoning Behind Drying Wood

Jul 27, 2021 The Reasoning Behind Drying Wood. Kiln drying is a standard practice in wood production mills and serves to efficiently bring green lumber moisture levels down to “workable” range–moisture content levels that will not end in the myriad of problems that can be caused by excess moisture levels in wood. These problems include warping and

Get More
What is a Moisture Barrier and When is it Needed for

What is a Moisture Barrier and When is it Needed for

Nov 25, 2020 A moisture barrier is used when installing floors or walls in areas prone to dampness or excess moisture, such as basements, ceilings, or crawl spaces (source). Flooring moisture barriers are placed beneath the floor’s underlayment. You can buy a barrier separately or get underlayment with a moisture barrier built-in

Get More
Manufacturing of Brick

Manufacturing of Brick

a minimal amount of water (up to 10 percent), then pressed into steel molds under pressures from 500 to 1500 psi (3.4 to 10.3 MPa) by hydraulic or compressed air rams. Drying. Wet brick from molding or cutting machines contain 7 to 30 percent moisture, depending upon the forming method

Get More
Vapor barrier - Wikipedia

Vapor barrier - Wikipedia

A vapor barrier (or vapour barrier) is any material used for damp proofing, typically a plastic or foil sheet, that resists diffusion of moisture through the wall, floor, ceiling, or roof assemblies of buildings to prevent interstitial condensation and of packaging.Technically, many of these materials are only vapor retarders as they have varying degrees of permeability

Get More
What Causes Damp and Mould on Walls and How to Fix It

What Causes Damp and Mould on Walls and How to Fix It

Hygroscopic salts can cause white staining and damp on your walls. Fix – The first thing to do is to trace and fix any leaks present. Once you have done this, you will need to remove all of the damp plaster from the affected area, right back to the wall’s surface behind. Then, treat the area with a salt neutraliser

Get More
Hot Weather Concrete Construction

Hot Weather Concrete Construction

Protect the concrete surface during placement with plastic sheeting or evaporation retarders to maintain the initial moisture in the concrete mixture. Provide sufficient labor to minimize the time required to place and finish the concrete, as hot weather conditions substantially shorted the times to initial and final set

Get More
Sulfate attack in concrete

Sulfate attack in concrete

Sulfate attack in concrete and mortar. Sulfate attack can be 'external' or 'internal'. External: due to penetration of sulfates in solution, in groundwater for example, into the concrete from outside. Internal: due to a soluble source being incorporated into the concrete at the time of mixing, gypsum in the aggregate, for example. External sulfate attack

Get More
Foundation Damp Proofing vs. Waterproofing - The Concrete

Foundation Damp Proofing vs. Waterproofing - The Concrete

But damp-proofing will only retard moisture; it can't stop a head of water bearing against the foundation. Nearly all waterproofing products can be applied to concrete block as well as poured concrete walls, and most of the same concerns and practical tips are relevant

Get More
What Is Nitrogen Purging? | Procedure and Why Nitrogen

What Is Nitrogen Purging? | Procedure and Why Nitrogen

Aug 21, 2018 Why Is Nitrogen Used for Purging? Nitrogen is dry and non-combustible, and the nitrogen displacement of combustible gases will prevent an unstable and potentially ignitable atmosphere. Simply put, the use of nitrogen in oil and gas industry equipment effectively displaces moisture and oxygen and creates a more stable climate

Get More
8 Truths about Concrete Moisture - Concrete Moisture

8 Truths about Concrete Moisture - Concrete Moisture

During the drying process, the concrete batch water, cement, aggregate, and other admixtures create tiny pathways within called capillaries. Once cured, the excess water in the slab moves through these capillaries to release the moisture. Since most concrete floors have a vapor retarder below them, this moisture must move upwards in order to escape

Get More
Use of Water Reducers, Retarders, and Superplasticizer

Use of Water Reducers, Retarders, and Superplasticizer

Water reducers, retarders, and superplasticizers are admixtures for concrete, which are added in order to reduce the water content in a mixture or to slow the setting rate of the concrete while retaining the flowing properties of a concrete mixture. Admixtures are used to modify the properties of concrete or mortar to make them more suitable to

Get More
Three Key Lessons about Moisture in Concrete| Concrete

Three Key Lessons about Moisture in Concrete| Concrete

Jun 14, 2019 Because different concrete moisture tests can return conflicting results, leaving contractors unsure how to proceed. This is especially true when testing older concrete floors where the contractor may have little idea of what was done when the concrete was originally poured. A story recently shared by one customer illustrates perfectly the pitfalls of using less reliable moisture testing

Get More
Water, Moisture and the water, cement and concrete

Water, Moisture and the water, cement and concrete

As a result, it limits the dispensing rate. Secondly, the sensitivity of most moisture sensors, especially the older resistive probes, reduces as the moisture increases, and is very poor at normal dry cast moistures. The result is that it is useless on slump concrete

Get More
Sweating Concrete Floors: Causes of Surface Moisture

Sweating Concrete Floors: Causes of Surface Moisture

Why Does My Concrete Floor Sweat? Causes of Surface Dampness on Concrete Slabs and Garage Floors: Humidity—warm and humid air condenses into surface moisture when it comes into contact with the cool surface of your concrete floor or slab.. Faulty/Missing Vapor Barrier—moisture from the ground can seep up and surface through the concrete if no vapor barrier has been installed or is faulty

Get More
Latest News