Inspection and Testing of Ready Mix Concrete
Ready Mix concrete refers to the on-site concrete mixing in which specialized concrete materials have been used. In Ready Mix concrete, the concrete materials are weigh-batch at a plant in a central mixer before the delivery of the concrete at the construction unit. The Ready Mix Concrete has been delivered to the construction site in plastic condition and in this case, any kind of further treatment is not required before placing in the position.
There are several unique factors which need to be considered in the Ready Mix Concrete that are as follows:
1. This type of Ready Mix Concrete is processed concrete which is unfinished material at the delivery time.
2. The quality and uniformity of the Ready Mix concrete varies due to a large number of factors. Some of the concrete is readily identified and controlled and others can be not easily controlled and obscured.
3. The quality of the end product of Ready Mix Concrete has been affected by the different phases of processing which are the variability and selection of the ingredients, the proportions of the ingredients, and other phases.
4. The ultimate quality and comprehensive strength of the Ready Mix Concrete can not be verified at the time of the sale, though, only the concrete ingredients have been tested in advance.
5. The Ready Mix concrete industry has been compelled to modify and adjust its products according to the requirements for the various uses of the Ready Mix concretes.
Importance of Ready Mix Concrete
There are several advantages of Ready Mix Concrete as compared to site mix concrete which are as follows:
➢ The quality of the Ready Mix Concrete is far better than the site mix concrete due to the use of the sophisticated equipment for batching and other concrete-making procedure.
➢ The Ready Mix Concrete usage helps to enhance the construction speed. For example, the site mix concrete has been prepared at the rate of 4-5 m3 per hour whereas, the Ready Mix Concrete has been prepared at the rate of 60 m3 per hour.
➢ There is no requirement for procuring and storing cement, sand, aggregate, water and admixtures at the construction site. This helps to reduce the space requirement at the construction unit as well as helps to reduce the customer’s efforts for procuring different construction materials thus helping to check the quality parameters of the concrete.
➢ In the case of the site mix concrete, lots of wastage has occurred while handling all the concrete materials. Whereas, in the case of Ready Mix Concrete, these kinds of waste have been minimized.
➢ The usage of Ready Mix Concrete is also eco-friendly as compared to the other types of concrete.
Essential components required for the quality control of the Ready Mix Concrete
The process of quality control of the Ready Mix Concrete has been divided into three different components which are:
Forward control
The forward control is the corrective action which includes the control of the material storage, control of the quality of the purchased material, design modification of the concrete mix, transferring and weighing of the concrete equipment, and also includes the plant mixer and the truck mixer has been used in the operational condition.
Immediate control
The immediate quality control of Ready Mix Concrete has been associated with the instant action to the quality control of the concrete. The immediate quality control of Ready Mix Concrete includes product control and production control. In the production control process, the concrete production at each plant has been systematically controlled. On the other hand, in the case of the product control process, the concrete mixes have been sampled and tested to determine the plastic density, air content, temperature, and workability of the concrete.
Retrospective control
In retrospective control, the concrete properties including air content, slump, aggregate grading, and others have been covered. This retrospective control has been associated with 28-day cube strength.
Different testing methods for the quality control of the Ready Mix Concrete
Slump testing
The slump testing process of the Ready Mix concrete helps to evaluate the freshly mixed concrete’s flow characteristics.
Testing of the air content
The air content testing of the Ready Mix Concrete has been conducted to determine if there is a requirement for the air content specifications in the concrete established by the engineer.
Testing the unit weight
In the case of the unit weight testing of the Ready Mix Concrete, the fresh concrete has been placed inside an open container in which weight and volume are known. This helps to get the density or the unit weight of the concrete. The unit weight of the Ready Mix concrete has been reported in pounds per cubic foot.
Testing of the existing concrete
In the case of forensic investigations or the retrofits of existing construction structures, knowledge about the total strength of the existing concrete structure is required. There are two ways through which the concrete strength can be established which are destructive testing and non-destructive testing.
To learn more, watch the following video tutorial.
Video Source: Civil Engineering Bitz!!
Testing of the destructive concrete
The destructive testing method is useful for obtaining more accurate values about the comprehensive strength of the concrete.
Flexural testing method
In the case of the concrete has been installed into the aircraft runway, the flexural print test or tensile strength test has been initiated.
