Effects of Fibre-Reinforced Plastic Wedge-Stick Slope on the Performance of Wind-Turbine Blade Root Connections

Round 1

Reviewer 1 Report

This work deals with the effects of Fibre-Reinforced Plastic components on the performance of wind-turbine Blade. The authors performed an extensive and theoretical study on the field. The whole work is interesting.

POINTS FOR IMPROVEMENT:

1. The authors used en masse commercial software wihout providing details about this software, neither the principles of the used software nor the parameters used in simulations.

2. You are reporting experiments. Do these experiments follow international standards as ISO, or national standars?

3. A brief literature review using GOOGLE revealed many relative works. The

literature review could be completed with emphasis on recent open access work.

4. What's the comtribution of this work relative to previous published work?

5. This work is closer to a tehnical report. Please provide details about your experimental and theoretical methods. For  example which are the main phenomena (elongation, bending, torsion,etc), these methods account for static or dynamic conditions, etc

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

Dear Authors! I have reviewed your submission "Effects of Fibre-Reinforced Plastic Wedge-Stick Slope on the Performance of Wind-Turbine Blade Root Connections" and found that it is a sound, worth and very practical report mainly devoted to Mechanical Engineering studies. I see no reasons to publish it in Coatings MDPI journal. I recommend another journal since I found nothing related with coatings (there were  no word "coating" detected in the text!). My main concerns are the following:

* No details are given on the wedge-stick installation procedure: surface preparation (slippery or adhesive chemicals), size tolerance of holes, bushing force etc.

* No details on non-destructive testing after installation is applicable.

* Figure 10 - no discussion on the peculiarities at "stress-displacement" curve having place at displacements bigger than 0.2 mm till failure. What are the pop-ups? 

Author Response

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Author Response File: Author Response.pdf

Reviewer 3 Report

·        The manuscript title needs to be changed as the authors described materials and methods.

·        Authors need to provide the nomenclature index.

·        Check the statement "Finite element analysis, sample testing, and full-size blade testing, and structural verification were conducted using an 84.5 m blade." However, the abstract section needs to re-write with error free sentence.

·        Figueres 1 & 2 may keep in result and discussion section if found suitable or omit from the manuscript.

·        Table 1 should be compiled with more parameters of proposed blade.

·        This statement is not clear "The coefficient of frictional contact was 0.2. The other type of contact pair was the bonding contact, which was applied between other contact surfaces."

·        Figure 7-10 need to improve the images quality and readability of texts. 

·        The statement "The danger point of the FRP wedge-stick with a transition slope of 1:7.3 was located on its long surface, with a shear stress of 27.989 MPa" need to re-write.

·        Figure 12, kindly do the leveling with appropriate dimensions.

·        Kindly re-write the statement of findings in conclusion section particularly "In this study, we only analysed the influence of the change in the length of the FRP wedge-stick slope on the overall structure. However, the effects of other size changes on the overall structure of the bushing insert cannot be ignored. Currently, the single-inclined transition mode is the most commonly used for FRP wedge-sticks. However, engineers have initiated research on the double-inclined transition mode. In the near future, a multi-inclined transition mode and even improved designs for FRP wedge-sticks could be developed."

English language need to improved.

Author Response

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Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

I am happy with the revision

Reviewer 3 Report

Accept.