Concrete Mix Design: Methods, and Benefits for Structures
Concrete has been made with different types of materials including water, cement, and aggregates such as sand or gravel. The mixture of concrete was made based on the construction needs. The design of the concrete mix is one of the important processes which can be done by following several steps, calculations and laboratory testing processes which help to determine the optimal ratio or proportion of the ingredients which is required for making concrete mix design. This concrete mix design helps to achieve the desired strength and durability of the concrete.
The proportion of the components of the concrete has been determined more precisely. The selection of the appropriate materials and the quantities of the materials is necessary for creating the concrete mix design which can meet the desired specifications for the long-term durability and strength of the concrete.
Factors Impacting Concrete Mix Designs
There are numerous factors that provide a significant impact on concrete mix designs which include:
➢ Different grades of concrete
➢ The size and shape of the aggregates
➢ The grading zone of the aggregates
➢ The pacific gravity of the materials
➢ The water absorption capacity of the aggregates
➢ Concrete’s slump value
➢ The method of concrete transportation
➢ The water-cement ratio of the concrete
➢ The specific gravity of the constituent materials that have been used while making concrete
➢ Different types of techniques are used in the construction of the concrete
➢ The degree of supervision that has been provided in the concrete production
Different Types of Concrete Mix Designs
Nominal Mix Concrete
In the case of the nominal mix concrete, the concrete proportions are prefixed. This type of concrete mix design has been used for small-scale construction processes. The concrete grade between M5 to M20 comes under the nominal concrete mix category. In the M15 grade concrete, the cement-to-sand-to-aggregate ratio is 1:2:4 which is fixed. The content of the cement for any kind of nominal concrete mix can be increased in the case of the quantity of the water is increased.
Standard Concrete Mix
In this type of concrete mix design, the concrete grade ranges between M25 to M50.
In the standard concrete mix, the proportion of the ingredients will be one part of cement, two parts of sand and four parts of aggregate.
Design Mix Concrete
After analyzing the properties of each of the ingredients of the concrete, the professional civil engineer is involved in determining the concrete mix ratio. The ratio of the concrete mix has been determined on the basis of the strength and quality of the concrete. In addition, various types of additives have been added to achieve the desired strength of the concrete as per the requirements of the construction processes. The design mix concrete has been used for large-scale construction procedures.
Grades of Concrete
The grade of concrete refers to the strength of the concrete which has been estimated after 28 days of the construction process. The concrete grade depends upon the types of concrete mix design and the structural integrity of the concrete. The grade of concrete has been involved in the selection of the appropriate concrete mix design such as the types and the size of the aggregates which helps to ensure that the concrete will meet the structural and functional needs of the concrete.
Different types of concrete grades and their usefulness
Ordinary concrete grade
M10, M15, and M20 concrete come under this type of concrete grade. The ordinary grade of concrete has a low compressive strength which ranges between 1,450 to 3,200 PSI. this concrete grade has been used for non-structural construction procedures.
M10
This type of concrete grade comprehensive strength of 1,450 PSI which is used for non-structural construction procedures.
M15
This type of concrete grade has 2,175 PSI which is used for constructing binding floors and pavements.
M20
M20 concrete grade has a strength of 2,900 PSI which is used for constructing workshops, floors, and garages.
Standard concrete grade
The standard concrete grade ranges between M25 and M45. this type of concrete grade possesses better comprehensive strength. In the case of constructing slurry pits, concrete girders, loading bays, or high-tensile beams, this type of concrete grade has been used.
M25
M25 has 3,625 PSI strength which is used for constructing the functional structure of the construction unit and provides internal support to the construction structure.
M30
M30 has 4,350 PSI which makes it more useful and durable for roads along with a lot of tear and wear including heavy vehicles and harsh weather conditions.
M35
This type of concrete grade has a comprehensive strength of 5,075 PSI which helps to provide this concrete a high consistency. This concrete grade is appropriate for the construction of the external walls of commercial buildings.
M40
It has a high PSI of 5,800 which helps to provide strength to this concrete grade for holding heavy structures including beams. This type of concrete grade has also anti-corrosive properties which are appropriate for the construction of septic tanks which hold potent chemicals.
To learn more, watch the following video tutorial.
Video Source: Civil Engineer Tonmoy Maity
High concrete grade
The concrete grade ranges between 6,525 and 9,425 PSI has been referred to as the high concrete grade. M45 to M65 come under the high concrete grade.
The high concrete grade has higher durability and strength. This type of concrete grade has been used for constructing high-end structures including bridges, dams, and others.
M45 to M65
This higher grade of concrete has exceptional durability and strength which helps to ensure the integrity of the critical construction structures.
