Ordinary Portland Cement |Portland Cement Types | Portland Cement Vs. Quikrete
Portland cement is the most widely used type of cement worldwide as a basic ingredient in concrete, mortar, stucco, and non-specialty grout.
It was developed in England in the early nineteenth century by Joseph Aspdin from other varieties of hydraulic lime and is typically made from limestone.
It is a fine powder that is made by heating limestone and clay minerals in a kiln to make clinker, grinding the clinker, and adding between 2% and 3% gypsum.
There are numerous types of Portland cement available. The most common type is grey Portland cement, referred to as ordinary Portland cement (OPC), however white Portland cement is also available.
It received its name due to its resemblance to Portland stone produced on the Isle of Portland in Dorset, England. It was named after Joseph Aspdin, who patented it in 1824.
However, his son William Aspdin is credited with inventing “modern” Portland cement in the 1840s.
Due to the caustic nature of Portland cement, it can result in chemical burns. The powder may cause irritation or, in the case of prolonged exposure, lung cancer, and may contain a variety of dangerous components, including crystalline silica and hexavalent chromium.
Environmental considerations include the high energy requirements for mining, manufacturing, and transporting cement, as well as the associated air pollution, which includes the discharge of greenhouse gases carbon dioxide, dioxin, NOx, SO2, and particulates.
Portland cement production accounts for around 10% of global carbon dioxide emissions. According to the International Energy Agency, cement production will increase by between 12 and 23% by 2050 to meet the world’s rising population’s needs.
Numerous studies are being conducted to determine the feasibility of substituting extra cementitious materials for Portland cement.
Portland cement is one of the least expensive materials commonly employed throughout the previous century due to the low cost and broad availability of the limestone, shales, and other naturally occurring components used in it.
Concrete made from Portland cement is one of the most adaptable building materials on the planet.
Ordinary Portland Cement Types
ASTM C150, “Standard Specification for Portland Cement,” defines ten different types of cement, five of which are widely considered to be the principal varieties utilized in precast plants:
· Type I – Normal/General Purpose
· Type II – Moderate Sulfate Resistance
· Type III – High Early Strength
· Type IV – Low Heat of Hydration
· Type V – High Sulfate Resistance
Type I Portland Cement (Normal/General Purpose)
Type I Portland cement is a general-purpose Portland cement that is suited for all applications that do not require the specific qualities of other types.
It is employed in situations where cement or concrete is not subjected to certain exposures, such as sulfate attack from soil or water, or an unpleasant temperature rise caused by hydration heat.
Pavements and sidewalks, reinforced concrete buildings, bridges, railway constructions, tanks, reservoirs, culverts, sewers, water pipelines, and masonry units are all constructed using this material.
Portland Cement Type II (Moderate Sulfate Resistance)
Type II Portland cement is used in applications that require protection against mild sulfate assault, such as drainage structures where sulfate concentrations in groundwaters are higher than average but not especially severe.
Generally, Type II cement generates less heat at a slower rate than Type I cement. Type II cement can be utilized in structures of substantial mass, such as huge piers, hefty abutments, and massive retaining walls, because to its mild heat of hydration (an optional criterion).
Its use will result in a decrease in temperature rise, which is critical when the concrete is placed in warm weather.
Portland Cement Type III (High Early Strength)
Type III Portland cement is a high-early strength Portland cement that achieves high strengths quickly, typically within a week or fewer.
It is utilized when forms must be removed rapidly or when the construction must be swiftly put into use. When used in cold weather, it enables a reduction in the regulated curing time.
Although richer Type I cement mixtures can be utilized to achieve high early strength, Type III, high early-strength Portland cement, may do it more successfully and affordably.
Type IA, IIA, IIIA Portland Cement
Specifications for three types of air-entraining Portland cement (Types IA, IIA, and IIIA) are given in ASTM C 150
They are chemically identical to ASTM Types I, II, and III, except that the admixture amounts of air-entraining ingredients are interground with the clinker during manufacturing to form minute, evenly distributed, and totally separated air bubbles. These cements result in more resistant concrete to freeze-thaw action.
Portland Cement Type IV (Low Heat of Hydration)
Type IV Portland Cement is a low heat of hydration cement designed for applications where the rate and amount of heat generated must be limited. It gains strength more slowly than Type I cement.
Type IV Portland cement is designed for use in big concrete constructions, such as gravity dams, where the temperature rise caused by curing heat is crucial.
Portland Cement Type V (High Sulfate Resistance)
Type V is a sulfate-resistant cement that is used exclusively in concrete that is subjected to severe sulfate action – primarily in areas with high sulfate concentration in the soils or groundwater.
When high sulfate resistance is required, a low Tricalcium Aluminate (C3A) content, often less than 5%, is required.
Type IV and V are widely applied in specific building applications that demand a high level of sulfate resistance or a low heat of hydration. Neither of these materials is a viable option for countertops.
Uses of Portland Cement
Portland cement is most widely used in the making of concrete. Concrete is made of aggregate (gravel and sand), cement, and water.
Concrete is a versatile building material that may be cast in virtually any shape and, once hardened, can function as a structural (load bearing) element.
Concrete can be cast-in-place for superstructures such as highways and dams or utilized to produce structural pieces such as panels, beams, and street furniture.
These can be supplied with on-site mixed concrete or with ‘ready-mixed’ concrete produced at permanent mixing plants.
Portland cement is also used in mortars (composed solely of sand and water), plasters and screeds, and grouts (cement/water mixtures pressed into gaps to strengthen foundations, roadbeds, and other structures).
When water is combined with Portland cement, the mixture sets in a matter of hours and hardens over the course of many weeks.
These processes vary considerably depending on the mix used and the curing circumstances, but a normal concrete set in approximately 6 hours and achieves a compressive strength of 8 MPa in approximately 24 hours.
After three days, the strength increases to 15 MPa, 23 MPa after one week, 35 MPa after four weeks, and 41 MPa after three months.
While the strength should continue to increase gradually as long as water is available for continued hydration, concrete is typically allowed to dry out after a few weeks, halting strength growth.
What is the Difference Between Portland Cement and Quikrete?
Cement is a binder, an adhesive. It is used to stick other things— in the case of concrete, sand and gravel— together. Portland cement is one of the components of concrete, and the amount of it in your concrete mix is very important. The more you use, the greater the compression loading of the finished concrete pour.
Quikrete is, first of all, a brand name. The Quikrete company has competition who sells the same things they do. But what your asking is, Quikcrete or sackcrete is a pre-mixed, just-add-water-and-mix concrete mixture. It includes Portland cement, along with sand and gravel.
QUIKRETE Concrete Mix consists of a uniformly blended, properly proportioned mixture of stone, gravel, sand, Portland cement and other ingredients approved for use in concrete.
• 40 lb (18.1 kg) bags
• 60 lb (27.2 kg) bags
• 80 lb (36.2 kg) bags