Review Reports

Round 1

Reviewer 1 Report

The manuscript presents nonlinear approximate equations for the Estimation of Horizontal Load Bearing Capacity of Circular PCFST with Diaphragm. The equation are obtained as a function of relevant non dimensional parameters thanks to statistical interpolation of FEM results. The goodness of the proposed formulas improves if the bulking mode is considered.

I suggest to clarify in the manuscript the following aspects:

- the actual influence of concrete quality, plastic deformation and cracking, and contact interaction with steel tube and diafragm is not clear. In addition to some comments, some diagram from fem analysis displaying the concrete damage could be useful.

- it is not completely clear which is the range of applicability of the proposed equations, how it is determined, and how it was used to select the experimental data for comparison.

- some more detail about the fem model could be added. For example, justify the adoption of linear element in presence of highly localized deformations.

 

Author Response

• the actual influence of concrete quality, plastic deformation and cracking, and contact interaction with steel tube and diafragm is not clear. In addition to some comments, some diagram from fem analysis displaying the concrete damage could be usefu
• Thank you for this essential point. To understand the behavior of PCFST, we added stress distribution for steel tube and concrete filling as figure 9 (see page 7) in revised manuscript. Besides, to understand the concrete damage we also added upper view of concrete filling just below diaphragm. Based on this figure, we added several comments at line 169-175 in page 7 and change title of section 3.1 from “3.1. Load-displacement curve” to “3.1. Load-displacement curve and equivalent stress distribution” in page 6 as highlighted green color.
• it is not completely clear which is the range of applicability of the proposed equations, how it is determined, and how it was used to select the experimental data for comparison.
• Radius thickness ratio parameterand Slenderness ratio parameter is in the range of Japanese Specifications for Highway Bridges, and it was written in original manuscript as “Based on the parameter limits defined in the Japanese Specifications for Highway Bridges [9],  is set to 0.06, 0.09, and 0.12, and  is set to 0.2, 0.3, and 0.4.”. So, we changed this part clearer with practical values as follows: “Based on the parameter limits defined in the Japanese Specifications for Highway Bridges [9],  is set to 0.06, 0.09, and 0.12, and  is set to 0.2, 0.3, and 0.4.”. Please see at line 75-77 in page 3 as highlighted green color.
• The experimental data was selected basing on the range of design parameter of Table 1. We added this information and practical range at line 380-382 of page 15 as highlighted green color.
• some more detail about the fem model could be added. For example, justify the adoption of linear element in presence of highly localized deformations.
• We added comment about why using linear element for FE modeling at line 106-112 in page 4-5 as highlighted green color.
• We improved quality of figure 5 (see page 5) in the revised manuscript to under stand the detail of FEM model as highlighted green color.

Author Response File: Author Response.pdf

Reviewer 2 Report

Please consider the comments presented in the reviwed pdf.

Comments for author File: Comments.pdf

Author Response

• Fig.8: Please improve graphic caption for improved visual analysis
• According to reviewer comment, we Improved Fig.8 (Note that Fig.8 became Fig.9 in revised manuscript by increase of number of figures based on other review’s comment) visibility by enlarge legends and increase the scale of both vertical and horizontal axis in the figure as highlighted yellow color.
• In addition to above change, we noticed that one legend in the figure is incorrect. The legend in the original paper was corrected to  in the revised manuscript.
• Fig.9: Please improve graphic caption for improved visual analysis
• According to reviewer comment, we Improved Fig.9 (Note that Fig.9 became Fig.10 in revised manuscript by increase of number of figures based on other review’s comment) visibility by enlarge legends in the figure yellow color.
• Please remove extra space
• According to reviewer comment, we removed extra space in the caption of horizontal axis of Fig.15a (Note that Fig.15 became Fig.16 in revised manuscript by increase of number of figures based on other review’s comment) yellow color.

Author Response File: Author Response.pdf