Feasibility Assessment of Implementing Semi-Interlocking Masonry as Infill Panels in Framed Building Construction
Round 1
Reviewer 1 Report (Previous Reviewer 1)
Comments and Suggestions for AuthorsThe study creats structural models to simulate the impact of various seismic loads on a bare reinforced concrete frame, a traditional unreinforced masonry infilled reinforced concrete frame, and a semi-interlocking masonry (SIM) infilled reinforced concrete frame. The study considers three locations, representing low, medium, and high-risk seismic areas in Australia, as well as additional factors such as building subsoil classes and importance levels. The feasibility of utilizing SIM as a construction material was assessed based on these considerations. Commens are as follows:
(1) The novelty of the work can be expressed in detail in the Abstract, Highlights, and Conclusion. The main content should concern your research idea and its experimental effect verification.
(2) The expression logic can be improved for your proposed method so that the innovation can be clearly understood. More expression of the mathematical analysis should be conducted to show your ideas clearly. Also, please try to highlight your proposed method and focus on it.
(3) More experimental result comparisons with references should be conducted for advantage discussion
(4) Figure 5(b) is not clear, and the figure needs replaced. In addition, how to determine the later forces in Figure 5(b), and the corresponding information should be given.
(5) Figure 7 and 16 are not clear, and the figures need replaced.
(6) Why not subject the structure to dynamic analysis? As far as I am concerned, the dynamic analysis represents a real situation and can relfect the realistic dissipation energy.
(7) The diagonal strut model should be verified by the current experiment resutls as the analysis of the paper is strongly dependent on the model.
(8) The detailed mechanical properties of Semi-Interlocking Masonry (SIM) should be given so that the reader can have a clear estimation of the advantage of the structural performance.
Author Response
Comment 1: The novelty of the work can be expressed in detail in the Abstract, Highlights, and Conclusion. The main content should concern your research idea and its experimental effect verification.
Response 1: The novelty of this research is highlighted in multiple sections of the submitted manuscript. For instance, it is detailed in the abstract on lines 17-19 and 24-26 and in the introduction on lines 92-101. Additionally, the conclusion has been revised to emphasize the novelty, with new content added on lines 506-516. The abstract of our manuscript presents our research idea: the evaluation of Semi-Interlocking Masonry (SIM) as an innovative building system. The abstract outlines the unique aspects of SIM, such as its ability to dissipate energy during seismic events due to the friction on the sliding bed joints.
Furthermore, it emphasizes the primary aim of assessing the viability of SIM panels as infill in multi-storey buildings across different seismic conditions in Australia. The study includes a comprehensive analysis using Strand7 on a three-storey structure incorporating both traditional masonry and SIM panels to verify the experimental effects. The comparison of displacement and base shear capacities under various seismic scenarios provides a thorough evaluation of SIM’s performance. This comparative analysis forms the core of our research, demonstrating the feasibility and potential advantages of SIM in contemporary construction. Authors believe that the detailed analysis and comparative results provide a robust verification of the efficacy of SIM panels.
Comment 2: The expression logic can be improved for your proposed method so that the innovation can be clearly understood. More expression of the mathematical analysis should be conducted to show your ideas clearly. Also, please try to highlight your proposed method and focus on it.
Response 2: One of the coauthors previously published a detailed mathematical analysis of the SIM panel design (see Reference #23 for more details). Furthermore, to address the complexity of the adopted method and enhance clarity, the authors have developed a workflow diagram that outlines the entire process. This diagram is now included as Figure 17, line 361, in the revised manuscript.
Comment 3: More experimental result comparisons with references should be conducted for advantage discussion
Response 3: Given the novelty of the SIM system, developed by the University of Newcastle, Australia, no experimental data exists beyond our own testing. In this study, we tested six 2m x 2m SIM panels and compared the experimental results with analytical methods and finite element (FE) analysis. While these comparisons provide a strong initial validation of the SIM panel performance, we recognize the need for additional experiments to further substantiate our findings and deepen the discussion on the advantages of SIM panels. Conducting more experiments is a potential direction for future research.
Comment 4: Figure 5(b) is not clear, and the figure needs replaced. In addition, how to determine the later forces in Figure 5(b), and the corresponding information should be given.
Response 4: Figure 5(b) depicts the model of a bare frame, which was extracted from the Strand7 model. The specific values that are unclear in the figure are detailed in Table 5, encompassing all 18 cases analyzed in this study. The lateral forces, determined by Equation 1 (line 136), are also presented in Table 5 and distributed at each level using Equation 3 (line 169). The forces are represented by F and member numbers are level in Figure 5(b).
Comment 5: Figure 7 and 16 are not clear, and the figures need replaced.
Response 5: Figure 7 and Figure 16 depict the model of SIM panel Type 1and Type 2, respectively, which was extracted from the Strand7 model. The specific values that are unclear in the figure are detailed in Table 5, encompassing all 18 cases analyzed in this study. The lateral forces, determined by Equation 1 (line 136), are also presented in Table 5 and distributed at each level using Equation 3 (line 169). The forces are represented by F and member numbers are level in Figure 5(b).
Comment 6: Why not subject the structure to dynamic analysis? As far as I am concerned, the dynamic analysis represents a real situation and can relfect the realistic dissipation energy.
Response 6: The authors recognize the importance of addressing this issue to ensure clarity and transparency in this study. However, it is essential to emphasize that this research is focused on analyzing the contributions of various structural elements—such as bare frames, traditional masonry, and Semi-Interlocking Masonry (SIM) panels—in resisting shear force through static analysis. Given the specific objectives of evaluating these elements' performance under static loading conditions and understanding their individual contributions to shear resistance, we believe that dynamic analyses are not necessary. While we acknowledge the significance of dynamic analyses and investigations into complex structural behaviors, we are confident that a simplified structural model is sufficient to effectively achieve our research goals. The manuscript has been revised in Section 2 (lines 126-133) to clearly articulate
Comment 7: The diagonal strut model should be verified by the current experiment resutls as the analysis of the paper is strongly dependent on the model.
Response 7: The equivalent compression strut method is a widely recognized practice endorsed in seismic codes for simulating traditional infill panels within frames. The mechanical parameters governing infilled frames, including strength and stiffness, are influenced by factors such as material properties, thickness, and width of the equivalent strut. The width of the strut depends on the contact length between the infill and the frame. The rationale for adopting the diagonal strut model is outlined in lines 126-133 of the current manuscript. However, it is important to note that this study focuses on the innovative SIM panels, which are not modeled based on the diagonal strut method.
Comment 8: The detailed mechanical properties of Semi-Interlocking Masonry (SIM) should be given so that the reader can have a clear estimation of the advantage of the structural performance.
Response 8: Table 1 presents the properties of the SIM units and panels used in this study. Previous research has extensively documented SIM's detailed properties. References 1, 2, 9, 11, 12, 13, 23, and 24 provide comprehensive information on SIM's mechanical properties.
Reviewer 2 Report (New Reviewer)
Comments and Suggestions for AuthorsSemi-Interlocking Masonry (SIM) represents an innovative building system, which employs a unique approach to interlocking mortar-less engineered masonry panels constructed from SIM units. These units are designed to offer substantial energy dissipation capacity, primarily attributed to the friction occurring on the sliding bed joints between the units within the panel during seismic events. The research content in this paper is innovative, but the following issues must be addressed before considering acceptance.
1. In the Figure 2, the dedtails of the Semi-Interlocking Masonry unit types should be provided.
2. For frame structures in earthquake resistant zones, the stiffness of frame columns is generally greater than that of frame beams. Therefore, the selection of cross-sectional dimensions for beams and columns in Figure 3 does not match the practical engineering application.
Author Response
Comment 1: In the Figure 2, the dedtails of the Semi-Interlocking Masonry unit types should be provided.
Response 1: The authors understand that the reviewer requested the dimentions of the SIM unit types. Based on the suggestion of the reviewer, dimensions of the SIM units are reported in line 68 and also marked in Figure 2 in the current manuscript. However, if the authors indicated curve details for topological SIM units and the specifics of the holes (slots and sockets) for mechanical SIM units. These details can be found in Reference #11.
Comment 2: For frame structures in earthquake resistant zones, the stiffness of frame columns is generally greater than that of frame beams. Therefore, the selection of cross-sectional dimensions for beams and columns in Figure 3 does not match the practical engineering application.
Response 2: The cross-sectional properties of beams and columns in this study are based on the design of a standard 3-storey, 3-bay structure. The beam section was determined from the design of a 4-meter long span RCC beam, using typical material properties in Australia. The column cross-section was designed according to the highest compressive load received by a column, adhering to Australian standards.
Reviewer 3 Report (New Reviewer)
Comments and Suggestions for AuthorsThe work is very interesting and of great interest especially for practical applications. However, some improvements need to be made in order to publish it.
- What the authors describe is a topic already widely debated in the scientific literature. The additional contribution that the authors want to make compared to the existing literature should be better described;
- The analysis method is clear and well explained. It would be useful to better specify where the adopted geometry of the frame comes from;
- It is not clear whether a variability of the input parameters has been adopted or whether they have been fixed. In this last case the limits of the results obtained should be better specified;
- How was the interaction of the infill response with the beam-column nodes taken into account?
Comments on the Quality of English Language
- An overall English review is recommended. The manuscript is overall well written but has some inaccuracies.
Author Response
Comment 1: What the authors describe is a topic already widely debated in the scientific literature. The additional contribution that the authors want to make compared to the existing literature should be better described;
Response 1: A similar comment made by Reviewer 1. The novelty of this research is highlighted in multiple sections of the submitted manuscript. For instance, it is detailed in the abstract on lines 17-19 and 24-26 and in the introduction on lines 92-101. Additionally, the conclusion has been revised to emphasize the novelty, with new content added on lines 506-516. The abstract of our manuscript presents our research idea: the evaluation of Semi-Interlocking Masonry (SIM) as an innovative building system. The abstract outlines the unique aspects of SIM, such as its ability to dissipate energy during seismic events due to the friction on the sliding bed joints.
Furthermore, it emphasizes the primary aim of assessing the viability of SIM panels as infill in multi-storey buildings across different seismic conditions in Australia. The study includes a comprehensive analysis using Strand7 on a three-storey structure incorporating both traditional masonry and SIM panels to verify the experimental effects. The comparison of displacement and base shear capacities under various seismic scenarios provides a thorough evaluation of SIM’s performance. This comparative analysis forms the core of our research, demonstrating the feasibility and potential advantages of SIM in contemporary construction. Authors believe that the detailed analysis and comparative results provide a robust verification of the efficacy of SIM panels.
Comments 2: The analysis method is clear and well explained. It would be useful to better specify where the adopted geometry of the frame comes from;
Response 2: This study selected a 3-story structure (adopted geometry) to represent typical building construction practices for an infill building in Australia. To achieve this, structural engineering principles and methodologies were employed to design a representative 3-story building. This process involved considering factors such as building codes, structural loadings, material properties, and construction practices relevant to low-rise structures. By adhering to these standards and principles, the study aims to ensure the accuracy and reliability of the findings regarding the performance of Semi-Interlocking Masonry (SIM) panels in low-rise construction. This comprehensive approach not only validates the structural integrity of the designed building but also enhances the applicability of the research outcomes to real-world construction scenarios in Australia.
Comments 3: It is not clear whether a variability of the input parameters has been adopted or whether they have been fixed. In this last case the limits of the results obtained should be better specified;
Response 3: The input parameters, such as dimensions and support conditions, for the Strand 7 model have been fixed for the bare frame, frame with traditional masonry and frame with SIM panels. This allows relative comparison between the various systems. The limitation in studying only one set of frame dimensions is acknowledged and the manuscript has been edited to reflect this limitation.
Comments 4: How was the interaction of the infill response with the beam-column nodes taken into account?
Response 4: As this study is comparative, focusing on the behavior of bare frames, traditional masonry, and SIM panels, the interaction between concrete beams and the frame remains consistent across all structures. Although the study does not specifically address this interaction, the comparative analysis provides a comprehensive understanding of the infill panels' demands within the broader structural context. The nodes connecting beam and column elements were considered fixed connections, as is standard in RCC frame analysis.
Comments on the Quality of English Language: An overall English review is recommended. The manuscript is overall well written but has some inaccuracies.
Response: The submitted manuscript was read carefully again and several sentences were edited to improve the English expression.
Round 2
Reviewer 1 Report (Previous Reviewer 1)
Comments and Suggestions for AuthorsI do not have more comments. I recommend publication.
This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.
Round 1
Reviewer 1 Report
Comments and Suggestions for Authors This study is to evaluate the viability of incorporating semi-interlocking masonry as infill panels in the construction of multi-storey buildings across diverse geographical locations with varying seismic conditions in Australia. To assess the feasibility of SIM panels in different conditions in Australia, a comprehensive analysis using Strand7 is conducted on a three-storey structure incorporating traditional masonry infill panels and SIM panels. The manuscript can be accepted after following revisions: 1. The detailed reinforcement details for beam and columns should be given in the manuscript. 2. The nonlinear material characteristics for the diagonal struct shoude be described. 3. The friction forces change with the incease of the earthquake intensity. How to determine the friction forces. Please clarify. 4. The discrepancy between the single struct model and the 3D detailed model should be clarified in the manuscript. 5. How to design the representative 3-story structure. Please comment.Author Response
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Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsThis paper underlines the use of Semi-Interlocking Masonry (SIM) that represents an innovative building system developed at the Centre for Infrastructure Performance and Reliability at The University of Newcastle, Australia. This system employs a unique approach to interlocking mortar-less engineered masonry panels constructed from SIM units. These units are designed to offer substantial energy dissipation capacity, primarily attributed to the friction occurring on the sliding bed joints between the units within the panel during seismic events. The primary aim of this study is to evaluate the viability of incorporating semi-interlocking masonry as infill panels in the construction of multi-storey buildings across diverse geographical locations with varying seismic conditions in Australia. To assess the feasibility of SIM panels in different conditions (according to Australian Standard AS1170) in Australia, a comprehensive analysis using Strand7 is conducted on a three-storey structure incorporating traditional masonry infill panels and SIM panels. The observations indicated that the base shears for low-risk seismic areas are comparatively low, posing no significant challenges for traditional masonry structures in these regions. Consequently, the utilization of SIM panels in low-risk seismic areas is deemed impractical. The implementation of SIM panels with a close gap is recommended for areas characterized by very high seismic risk. Finally, SIM panels with an open gap prove to be more efficient in dissipating earthquake energy compared to traditional masonry, while maintaining drift ratios well below the maximum limit of 1.5%.
This paper is extensive but the following minor revision is suggested to improve its quality:
The authors should justify better the design of the reinforced concrete beams and columns of the moment-resisting frame with the equivalent static method. Considerations should be made about their performance in the various performance stages in accordance to the performance of the SIM. Their interaction might not be the focus of this study but the infill panel's demands might lead to wrong conclusions without considering this interaction.
Finally, related to the employed software a short description of its utilities related to its incorporated frame elements and analysis' types is necessary.
Author Response
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Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for AuthorsThe paper examines the possibility of using semi-interlocking masonry as infill panels in the construction of multi-storey buildings in Australia. The paper is quite vaguely worded and it is not always clear which part of the paper refers to the paper author's contribution and which part is taken from the literature. Similarly, comparisons are made with models that have not been presented before (e.g. page 9, lines 258-260). In addition, it deals with the strongly non-linear behavior of the analyzed frame system with special semi-interlocking masonry infill, for the analysis of which it is generally hardly possible to apply the equivalent linear static analysis nor a simple linear macro model with the equivalent diagonal strut as masonry infill. In general, the model is described very narrowly, without giving details on the modeling of the non-linearities, and it also seems that the analysed infill has not been taken into account in the estimation of the parameters used in the equivalent static analysis method (page 5, lines 146 – 156). The results of the analysis (page 11, line 309 – 'The observed discrepancy between the theoretical and experimental values is substantial...') support the above mentioned facts, which are attempted to be corrected by the introduction of an appropriate reduction factor. Moreover, the chosen model (Figure 3) is very limited, and only by comparing the behavior of such an isolated model without varying its various characteristics does not make it possible to achieve the objectives set in the paper.
To summarize, the methodology chosen to solve the objectives set in the paper is not suitable, the results of the analysis carried out in this way are not representative, so that I suggest that the paper should not be published in this version.
Author Response
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Author Response File: Author Response.pdf
Round 2
Reviewer 3 Report
Comments and Suggestions for AuthorsThis reviewer still thinks that the proposed improvements to the work do not eliminate the main objections made in the first review and remains with his assessment given in the first review.
Author Response
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Author Response File: Author Response.pdf
