Cable Force Identification for Pre-Stressed Steel Structures Based on a Multi-Frequency Fitting Method

Round 1

Reviewer 1 Report

This manuscript established the analytical model of cable vibration and proposed an efficient multi-span cable test method. The analysis of experimental data is comprehensive and this research is meaningful for the engineering applications. There are some comments for this manuscript:

1 The introduction part should be presented more logically, e.g. Wang et al. [37] is related to theoretical work, rather than the finite element one. That should be placed in the previous paragraph about theory work.

2 The Figure 5 seems not so clear.

3 The error between predicted and actual value should be listed completely in Table 3.

4 The unit should be “kN”, rather than “KN”.

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

Based on the vibration equations of single-span and multi-span cables, the relationships between cable force and vibration frequencies are established in this paper in consideration of elastic boundary conditions. Using the measured frequencies of the cable (the number of frequencies should be larger than that of unknown parameters to be determined), the cable force and the restraint stiffnesses of supports are determined based on the unconstrained optimization algorithm. The accuracy of the proposed method for the cable force identification is verified by the results of two experiments. Indirectly identifying the cable force using measured frequencies is a convenient test method in engineering. According to the results provided in the paper based on experimental tests, the proposed method appears to be effective. However, the paper should be revised based on the comments below before being accepted.

1. It is suggested that the title of the paper be revised to "Cable Force Identification for Prestressed Steel Structures Based on a Multi-Frequency Fitting Method".

2. The quality of the English writing needs to be improved. It is recommended to seek the help of professional English editing agencies.

3. The expressions of units are not standardized, for example, kN was written as KN.

4. How the flexural rigidity (EI) of the cable is determined? Is it possible to also include the flexural rigidity as a parameter to be fitted.

5. Figure 9 and Figure 13 looks blurry. The Chinese characters in these two figures should be translated into English.

6. What specific method is the unconstrained optimization algorithm for solving the optimization problem (Eq. (18))?. Using this method, will there be multiple optimal solutions?

7. What does the "calculation times" in Tables 2 and 3 refer to? Why doesn't the initial values of cable force appear in Table 3, as in Table 2? The five identified cable forces in Table 3 are quite different. Can the reasons be analyzed?

8. The introduction of the cable safety monitoring system in Section 4 may not be included in the paper.

9. In the conclusion, it is mentioned that the nonlinear vibration characteristics of short and coarse cables are studied, but it does not seem to be discussed in the paper.

Author Response

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Author Response File: Author Response.pdf

Reviewer 3 Report

Most of contents of ch 2 are very well known.

It seems that experimental works are conducted by simply using commercial devices and software.

Author Response

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Author Response File: Author Response.pdf