The Sonic Resonance Method and the Impulse Excitation Technique: A Comparison Study

Round 1

Reviewer 1 Report

This manuscript presents a good topic, however, its needs major improvements as mentioned below:

1- The introduction section has sufficient information about the study of the authors, however, I still do not see the relevance of equation (1); please explain more of its relevance. 

 

2- The results section should be expanded and more explained by the authors. More sentences should be written to clearly explain the data given in Tables 2 and 3 and Figure 3. More specifically, please explain why E (SRM) and E (IET) are different and which one of the values are more accurate? Is there any rationale for this?

 

3- Conclusions is very short. You only explained what is done and what is obtained. There is no meaningful scale/length for the conclusions part when we compare it with Introduction section etc. Please include all new and significant conclusions that this study gives to the readers. 

 

Overall, it is an interesting topic. I believe the manuscript can be published after the above comments are addressed. 

Author Response

This manuscript presents a good topic, however, its needs major improvements as mentioned below:

1- The introduction section has sufficient information about the study of the authors, however, I still do not see the relevance of equation (1); please explain more of its relevance. 

Answer:

Equation (1) is a basic equation for calculation of Young´s modulus from the sample parameters (dimensions and mass) and resonant frequency of the flexural vibrations. The equation (1) is given in standards together with formulae for calculation of the correction coefficient. We added some short explanation into the manuscript.

 

2- The results section should be expanded and more explained by the authors. More sentences should be written to clearly explain the data given in Tables 2 and 3 and Figure 3. More specifically, please explain why E (SRM) and E (IET) are different and which one of the values are more accurate? Is there any rationale for this?

Answer:

The section “Results” was rewritten and expanded.

 

3- Conclusions is very short. You only explained what is done and what is obtained. There is no meaningful scale/length for the conclusions part when we compare it with Introduction section etc. Please include all new and significant conclusions that this study gives to the readers. 

 

Answer:

The Conclusions describes basic conditions of experiments (methods SRM and IET, shapes of samples and their material) as well as results of comparison between resonant frequencies measured with SRM and IET. It was confirmed equality of these measurements. This was the main object of the article. Description of SRM and IET is unimportant, so we did not give it into the Conclusions.

 

Overall, it is an interesting topic. I believe the manuscript can be published after the above comments are addressed. 

Reviewer 2 Report

Reviewer's opinion

 

The article deals with the equivalence of the sonic resonant method (SRM) and the impulse excitation technique (IET) to measure the resonance frequencies in materials and, thus, evaluate the modulus of elasticity. Both methods have the same theoretical base to obtain the Young´s modulus. The study shows that both methods produced the same values of a resonant frequency.

 

The article is relevant to the readers of Applied Sciences. It is well written, with adequate analysis for scientific research. Thus, the reviewer proposes its acceptance for publication in Applied Sciences

 

Nevertheless, the reviewer has the following questions.

 

In the authors' opinion, are both methods appropriated to obtain the Young´s modulus for steel-fiber reinforced concrete?

 

Is there any significant difference between the calculated values of dynamic and static modulus of elasticity?

Author Response

The article deals with the equivalence of the sonic resonant method (SRM) and the impulse excitation technique (IET) to measure the resonance frequencies in materials and, thus, evaluate the modulus of elasticity. Both methods have the same theoretical base to obtain the Young´s modulus. The study shows that both methods produced the same values of a resonant frequency.

The article is relevant to the readers of Applied Sciences. It is well written, with adequate analysis for scientific research. Thus, the reviewer proposes its acceptance for publication in Applied Sciences

Nevertheless, the reviewer has the following questions.

 

In the authors' opinion, are both methods appropriated to obtain the Young´s modulus for steel-fiber reinforced concrete?

Answer:

Steel-fiber reinforced concrete is not isotropic material. It needs a much more complex equation to describe a flexural vibration of the rectangular prism made from such material. But, in practice, IET and SRM are applied for measuring Young´s modulus using prismatic concrete samples. The equation (1) is used for its calculation.

 

 

Is there any significant difference between the calculated values of dynamic and static modulus of elasticity?

Answer:

To measure static and dynamic elastic moduli, different methods are used. The base of the static methods is applying of relatively big known force which causes deformation (flexure, prolongation) of the sample. If the sample is brittle, the deformation cannot be large. This leads to a relatively low precision of the static methods for such materials (ceramics, glass).

Dynamic modulus is higher than the static modulus. For example, experiments with different concrete and rock samples showed 5 - 10 % difference.

Round 2

Reviewer 1 Report

This version can now be published in this format.