Category: Concrete

The following precautions have to be observed:

Lime concrete is used for

Good lime concrete is prepared using hydraulic lime. Fat lime is not used as it is not suitable to use in large masses. The sand to be used should be free from impurities. The coarse aggregates used for lime concrete are broken bricks or broken stones. The water used should be clean. The mix proportion… Continue reading Preparation of Lime Concrete

Ingredients of Lime Concrete Lime concrete is made of lime, fine aggregate and coarse aggregate and mixed in suitable proportions in addition to water. Hydraulic lime is generally used as a binding material, sand, surkhi and cinder are used as fine aggregates, and broken bricks or broken stones are used as coarse aggregates.

It consists of two parts, viz., the mechanical ionic pulse velocity method and the ultrasonic pulse velocity method. The mechanical sonic pulse velocity method consists of measuring the time of travel of longitudinal or compressive waves generated by a single impact hammer blow or repeated blows. The ultrasonic pulse velocity method consists of measuring the… Continue reading Pulse Velocity Method

Here a rod is embedded in concrete blocks. These are pulled out and the strength of the concrete is determined. The ideal way to use the Pullout test in the field is to incorporate assemblies for pull out in the structure itself. These could be pulled out and the strength determined.

Here X-rays and gamma rays are used. When X-rays and gamma rays are passed through concrete, the electromagnetic spectrum penetrates concrete but undergoes attenuation in the process. The degree of attenuation is a function of the kind of matter traversed, its thickness and the wavelength of the radiation. Further, the intensity of the incident gamma-rays… Continue reading Radioactive Method

This is a new technique which is used to determine the moisture content and the cement content. This method employs the scattering of neutrons directed towards the concrete and the number of neutrons returned. With a standard relationship number of neutron and water content/cement content, the required water or cement content can be obtained.

It is another important non-destructive method used to determine the compressive strength and other properties. The fundamental principle on which the method is based is the velocity of material through a material. A mathematical relation could be made between the resonant frequency of the material to the Modulus of Elasticity of the material. The property… Continue reading Frequency Method