Review Reports - Seismic Performance Evaluation of RC–Masonry Hybrid Systems: A Comparative Study with İsa Divanli Mosque as a Case Example

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors Manuscript ID: buildings-3852169 Title: Seismic Performance Evaluation Of Rc-Masonry Hybrid Systems: A Comparative Study With İsa Divanli Mosque As A Case Example. Please consider the following comments: - Quantify the abstract by values like "Normalized Diplacement Index"

-The introduction could better highlight the research gap: while many studies exist, few apply calibrated FEM to historic hybrid systems with real earthquake damage data.

-The detail of modeling should be discussed about the FE model. (explicit or implicit , ...)

-NDI is a strong contribution, but its engineering interpretation should be expanded.

- Does your result emphasize that Hybrid systems should not be used in new seismic constructions unless strict detailing is ensured? this can be one of your results.

- Can you recommend that for historical structures, retrofit strategies (steel ties, RC jacketing, grout injection) should be considered?

Please consider higher resolution of pictures.

Comments on the Quality of English Language

Dear the Editor

The manuscript is well established and after the minor revsion can be accepted based on your consideration.

Best Regards

Author Response

Manuscript ID: buildings-3852169 Title: Seismic Performance Evaluation Of Rc-Masonry Hybrid Systems: A Comparative Study With İsa Divanli Mosque As A Case Example. Please consider the following comments:

- Quantify the abstract by values like "Normalized Diplacement Index"

Response: The abstract has been updated to include numerical values such as displacement magnitudes and the Normalized Displacement Index (NDI), providing clearer quantification of the study’s contributions.

-The introduction could better highlight the research gap: while many studies exist, few apply calibrated FEM to historic hybrid systems with real earthquake damage data.

Response: The introduction has been expanded to emphasize the scarcity of studies applying calibrated FEM to historic hybrid systems informed by actual earthquake damage observations.

-The detail of modeling should be discussed about the FE model. (explicit or implicit , ...)

Response: Details regarding the modeling procedure have been clarified. An implicit solver has been employed in ANSYS Workbench, with 20-node solid elements used for structural components. Reinforcement in RC members has been represented with equivalent smeared properties calibrated from Ferroscan data.

-NDI is a strong contribution, but its engineering interpretation should be expanded.

Response: The interpretation of the NDI has been expanded, linking it to stiffness compatibility, displacement-to-stress ratios, and implications for failure initiation in hybrid systems.

- Does your result emphasize that Hybrid systems should not be used in new seismic constructions unless strict detailing is ensured? this can be one of your results.

Response: The conclusions have been updated to emphasize that RC-masonry hybrid systems should not be used in new seismic construction unless strict detailing ensures stiffness compatibility and safe force transfer.

- Can you recommend that for historical structures, retrofit strategies (steel ties, RC jacketing, grout injection) should be considered?

Response: Recommendations for retrofit strategies in historical structures have been added, including the use of steel ties, RC jacketing, and grout injection.

- Please consider higher resolution of pictures.

Response: All figures have been updated with higher-resolution images in the revised manuscript.

Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

This study investigates the seismic performance of different structural schemes for the İsa Divanlı Mosque through numerical simulation, demonstrating certain practical relevance. The following modifications and suggestions are provided:

The section on finite element theory (Eqs. 1 to 9) could be condensed to improve conciseness.
A more detailed discussion of the finite element modeling approach is recommended. Specifically, please clarify the types of elements adopted for different structural components (e.g., shear walls and domes)—whether solid or shell elements were used—and whether reinforcement was considered in the shear walls. Additionally, please explain how material parameters were determined in the absence of experimental data.
When comparing different lateral force-resisting systems, it is essential to ensure consistency in the parameters. For instance, were the thicknesses of the shear walls and masonry walls taken as equal? Such assumptions should be clearly stated in the comparative analysis section.
The conclusions of the study appear somewhat self-evident. It would be valuable to incorporate a comparative discussion on retrofitting or strengthening costs, as this would enhance the practical guidance for engineering applications.

Author Response

The section on finite element theory (Eqs. 1 to 9) could be condensed to improve conciseness.

Response: The finite element theory section has been condensed by retaining essential formulations.

A more detailed discussion of the finite element modeling approach is recommended. Specifically, please clarify the types of elements adopted for different structural components (e.g., shear walls and domes)—whether solid or shell elements were used—and whether reinforcement was considered in the shear walls. Additionally, please explain how material parameters were determined in the absence of experimental data.

Response: Clarifications have been added regarding element types, reinforcement representation, and material parameter definition. All structural components have been modeled using solid elements. Reinforcement has not been modeled discretely but represented with equivalent smeared properties. Where experimental data were unavailable, parameters have been assigned based on laboratory tests and relevant standards.

When comparing different lateral force-resisting systems, it is essential to ensure consistency in the parameters. For instance, were the thicknesses of the shear walls and masonry walls taken as equal? Such assumptions should be clearly stated in the comparative analysis section.

Response: The comparative analysis has been clarified, and it has been stated that consistent wall thicknesses were assumed across all models.

The conclusions of the study appear somewhat self-evident. It would be valuable to incorporate a comparative discussion on retrofitting or strengthening costs, as this would enhance the practical guidance for engineering applications.

Response: The conclusions have been expanded to include practical implications, with specific attention to the cost aspects of retrofitting hybrid systems compared to pure RC or masonry alternatives.

Author Response File: Author Response.docx

Reviewer 3 Report

Comments and Suggestions for Authors

The article "Seismic Performance Evaluation Of Rc-Masonry Hybrid Systems: A Comparative Study With İsa Divanli Mosque As A Case Example " seems good. This study aims to evaluate the benefits and drawbacks of RC-masonry hybrid systems by performing a comparative numerical analysis of three structural configurations. As a representative case study, the historical İsa Divanlı Mosque in Kahramanmaraş, Turkey - severely damaged during the 6 February 2023 earthquakes - is modeled under three scenarios: (Configuration A) full RC structure with shear walls, (Configuration B) unreinforced masonry, and (Configuration C) the existing hybrid form with RC dome and slabs over masonry walls. Finite element models were developed for each case, and their seismic responses were analyzed under identical loading conditions. Following comments should be addressed:

There are too many figures. Only very important ones should be presented in the main text and important ones may be shown in annexure. Also, few figures can be merged, e.g. figures 1, 2 and 3 can be shown as a, b and c in one figure. Similarly, figures 4 and 5 can be shown as a and b in one figure.
Only concrete and masonry are being evaluated. What about the other materials?
How the joint and connection details are being perceived and used in modelling?
Figures 11 and 12: how much is the compromise in getting as-built drawings? Also, how much simplicity is being assumed from as-built drawing to FE model?
Section 6.2: how the model is calibrated, particularly from initial state to crack state? Which loadings are being considered?
What are the considerations from non-structural elements?
Figures 14 to 17: It is an excellent effort to get the current structural stability of the structure. But the initial state i.e. without any damage also matters? Which assumptions are being made for this?
Figure 19 to 23: results are nicely shown. But the question is about its relevance to real conditions. How is it verified?
The author should elaborate the ground conditions of structure in order to match the results.
The outcome/results should also be further elaborated.

Author Response

The article "Seismic Performance Evaluation Of RC-Masonry Hybrid Systems: A Comparative Study With İsa Divanli Mosque As A Case Example " seems good. This study aims to evaluate the benefits and drawbacks of RC-masonry hybrid systems by performing a comparative numerical analysis of three structural configurations. As a representative case study, the historical İsa Divanlı Mosque in Kahramanmaraş, Turkey - severely damaged during the 6 February 2023 earthquakes - is modeled under three scenarios: (Configuration A) full RC structure with shear walls, (Configuration B) unreinforced masonry, and (Configuration C) the existing hybrid form with RC dome and slabs over masonry walls. Finite element models were developed for each case, and their seismic responses were analyzed under identical loading conditions. Following comments should be addressed:

There are too many figures. Only very important ones should be presented in the main text and important ones may be shown in annexure. Also, few figures can be merged, e.g. figures 1, 2 and 3 can be shown as a, b and c in one figure. Similarly, figures 4 and 5 can be shown as a and b in one figure.

Response: Figures have been merged where possible (e.g., Figures 1–3 and 4–5).

Only concrete and masonry are being evaluated. What about the other materials?

Response: The scope has been clarified. The mosque consists only of RC and masonry, and no other materials have been identified in the current structure.

How the joint and connection details are being perceived and used in modelling?

Response: Clarifications have been added regarding connection modeling. RC joints have been represented as rigid zones, while RC-masonry interfaces have been modeled as contact surfaces to account for discontinuities in force transfer.

Figures 11 and 12: how much is the compromise in getting as-built drawings? Also, how much simplicity is being assumed from as-built drawing to FE model?

Response: The modeling approach has been clarified. As-built drawings have been used with minimal simplification, excluding only non-structural decorative features, while the main structural geometry has been preserved.

Section 6.2: how the model is calibrated, particularly from initial state to crack state? Which loadings are being considered?

Response: It has been clarified that calibration has been carried out in the elastic and micro-crack range, based on ambient and forced vibration tests. Full crack propagation has not been simulated due to safety constraints.

What are the considerations from non-structural elements?

Response: It has been clarified that non-structural elements have not been considered in the finite element modeling.

Figures 14 to 17: It is an excellent effort to get the current structural stability of the structure. But the initial state i.e. without any damage also matters? Which assumptions are being made for this?

Response: The initial undamaged condition has been assumed using average intact material properties obtained from laboratory tests.

Figure 19 to 23: results are nicely shown. But the question is about its relevance to real conditions. How is it verified?

Response: The results have been verified by comparing simulated damage patterns with observed earthquake-induced damages in the mosque.

The author should elaborate the ground conditions of structure in order to match the results.

Response: Ground conditions have been elaborated by including soil classification and Vs30 values.

The outcome/results should also be further elaborated.

Response: The discussion has been expanded to highlight design implications and retrofit priorities, stressing the unreliability of hybrid systems despite similar numerical indices to RC.