Constitutive Model for Estimating Concrete Strength Using Ultrasonic Test Considering Mixing Ratios

Evaluation of concrete strength is one of the important issues in the concrete industry and concrete structures. In most cases, during construction, samples of concrete are picked up and after curing, according to the existing standards, they are subjected to uniaxial compression and based on the applied force, the strength of the concrete is determined. Minimum strength of concrete can be predicted but in many cases, due to reasons such as lack of proper implementation, concrete strength in structure with design strength is different. Core drilling is one of the accepted in-situ tests for measuring the strength of concrete that is a destructive method. Providing a non-destructive method that can estimate the strength of concrete in a structure in many cases is a remedial. In this research, by providing concrete samples with different mix design, in addition to studying the effect of mixing ratios on concrete strength and ultrasound wave velocity, a relationship between concrete strength and ultrasonic wave velocity is presented. Also, a comprehensive relationship is presented to estimate the strength of concrete considering water to cement ratio and the ratio of fine aggregate to course aggregate.