ASTM stands for American Society for Testing and Materials and is an international society which sets standards for various materials, products, works.
Cement can be classified on various factors and generally types of cement are Ordinary portland cement, Rapid hardening cement, Extra rapid hardening cement, Low heat cement etc.
According to ASTM cement is classified as
ASTM C150 further classified into 8 different types and which are shown in the image below. The classification of ASTM C150 is type I, type IA, type II, type IIA, type III, type IIIA, type IV.
As per ASTM cement containing a high amount of C3S content is termed as Type I cement. Type I cement is generally used in general concrete construction where the special properties specified for type II, type III, type IV, type V are not required.
Higher C3S content results in faster rate of reaction and development of early strength.
Moderate Sulphate Resistant Cement or High Heat of Hydration Cement
Type II cement used for general constructions that are exposed to moderate sulphate action or where moderate heat of hydration is necessary. To attain the moderate heat of hydration C3A content is kept below 8%.
As type II cement has low heat of hydration, it can be used in hot water. Type II cement gains its maximum strength in 45 days.
Rapid Hardening Cement
Type III cement has high C3S content and low C2S content that results in high early strength and has a faster rate of reaction due to C3S content.
Type III cement has high early strength eg. strength in 3 day’s = Strength of OPC in 7 days, that is why the type III cement is used when very fast hardening is required.
Fast hardening is generally required where there is need to remove form work early and when minimum strength before further construction is to be gained.
Because of the high heat of hydration type III cement should not be used for mass concrete constructions. On the other hand in cold conditions like in snowy regions, it is better to use type 3 cement as it has a faster rate of reaction and high early strength also high heat of hydration delays the setting of concrete for some time.
Low Heat Cement
Type IV cement is generally used where low heat of hydration is required like in hot conditions. To have low heat of hydration type IV cement consist of low C3S content less than 30%(generally taken between 25 to 50%) and also low C3A content which releases 40% more heat than C3S.
Low heat cement is best for mass concrete construction as it sets very slowly it will get more time before setting to get easily transported to the right spot.
High Sulphate Resistance Cement
Type V cement is used when high sulphate resistance is required. As C3A is weak in sulphate resistance the C3A content is kept less than 5%. Type V cement consists of an intimate and uniform blend of type I portland cement and finely granulated slag. Slag percentage should be 25 to 70% of the weight of Portland blast furnace slag cement.
Basically, Type IA, IIA, IIIA cement are type I, II, III cements with the presence of air-entraining agents. These types of cement are generally used where the property of air-entrainment in concrete is needed along with the properties of the respective types of cement.
The infographic below shows the whole ASTM classification of cement.
ASTM C595 consist blended hydraulic cement for both general and special applications using slags or pozzolana or both with Portland cement or Portland cement clinker or slag with lime.
This consists of an intimate and uniform blend of Portland Cement (or Portland Blast Furnace Slag Cement) and fine pozzolana in which the pozzolana content is between 15 and 40 percent of the weight of the total cement.
This is also known as Portland blast furnace slag cement.
This is also known as Ternary blended Cement
This is also known as Portland-Limestone Cement
Some blended cement has special performance properties verified by additional testing. These are designated by letters in the type of cement in the following manner.
For example Type IP(MS) is a Portland-Pozzolana cement with moderate sulfate resistance properties. Other special properties are designated by (HS) for high sulfate resistance, (A) for air-entraining cement, (MH) for moderate heat of hydration, and (LH) for low heat of hydration. Refer to ASTM C595 for more details.
In ASTM C1157 the detailed classification is done on the basis of performance and generally done in industries. Following table describes performance attributes of ASTM C1157
|Type GU||General Use|
|Type HE||High Early-Strength|
|Type MS||Moderate Sulfate Resistance|
|Type HS||High Sulfate Resistance|
|Type MH||Moderate Heat of Hydration|
|Type LH||Low Heat of Hydration|
Cement is classified on the basis of a large number of factors like the required performance of concrete, environmental conditions, or conditions of placement. ASTM classifies cement based on their composition of raw materials.
Basically ASTM classifies cement as 1 | Portland Cement ASTM C150, 2 | Blended Cement ASTM C595, 3 | By Performance Attributes ASTM C1157.
Type 1 – Normal Cement
Type 2 – Moderate Sulphate Resistant Cement
Type 3 – High Early Strength
Type 4 – Low heat Cement
Type 5 – High Sulphate ResistanceWhat are the 5 Types of Cement?
The ‘ASTM’ stands for “American Society of Testing Materials”.
Portland Cement ASTM C150
Blended Cement ASTM C595
By Performance Attributes ASTM C1177
These are the ASTM standards of cement.