Analysis of Factors Affecting Prefabricated Building Quality Based on ISM-BN

Round 1

Reviewer 1 Report

The authors did a good job within this work but the reviewer has the following comments:

1. The authors focused on the points of weakness of prefabricated building construction without even mentioning its merits. If it has no merits, why is it growing globally!!! You need to revisit this issue.

2. Some of the figures are obviously taken from other publications (e.g. figure 3), they should be reproduced or cited with permission of re-use.

3. I don't think having only one case study is sufficient to draw such conclusions. I suggest having one more case study.

4. Some other comments are inserted in the pdf

Comments for author File: Comments.pdf

Author Response

Thank you for your comments.Here are our changes.

1.Comment: The authors focused on the points of weakness of prefabricated building construction without even mentioning its merits. If it has no merits, why is it growing globally!!! You need to revisit this issue.

Response: Thank you for the constructive suggestion. We have included the general advantages of prefabricated buildings and why they have grown significantly in industrialized countries in the Introduction Section, as the following: "At the beginning of the 20th century, industrialized countries such as the United States and the United Kingdom were desperate to solve their housing needs, and the construction of prefabricated buildings was found to be one of the effective solutions[2]. The construction method of prefabricated buildings has led to a significant reduction in construction time and cost, which has proved to deal with various housing problems. For instance, energy-efficient materials such as recycled steel can promote environmental sustainability for prefabricated buildings in many industrialized countries[3]. As a result, there has been a large growth in prefabricated buildings globally since World War II. In recent years, prefabricated buildings have received significant attention from the Chinese government. "

2.Comment: Some of the figures are obviously taken from other publications (e.g. figure 3), they should be reproduced or cited with permission of re-use.

Response: Thank you for the comment. We have revisited the figures in our manuscript and confirmed that all figures in this paper are drawn by the authors using software including MS Word and GeNIe.

3.Comment: I don't think having only one case study is sufficient to draw such conclusions. I suggest having one more case study.

Response: Thank you for the suggestion. The case study adopted in this paper is a typical prefabricated building project in Nantong, which is one of the important cities in China known for its construction industry, and the managers who participated in filling out the questionnaires were all from the management team of this project. They are all experienced professionals who have experienced numerous prefabricated building projects and can therefore make comprehensive judgments about the development of the local prefabricated building industry. The authors believe that the results of the case study are reliable and are in line with the construction practice of the prefabricated building industry. Considering that it was a typical prefabricated building project and that majority of the managerial professionals in this project were invited for the case study, we believe that adding another case study would only yield similar results.

4.Comment: Some other comments are inserted in the pdf.

Response: Thank you for the comments. The modification of this article is as follows:

① Previously, the authors failed to distinguish the difference between architectural and structural, so here we clarify that the study of the design stage in this paper applies to structural design.

②The fifth sentence of the third paragraph of Section 1. was changed, as the following: "In order to systematically identify the factors that affect the quality of assembled buildings, structural equation modeling was used to develop an assessment method to measure the impact of these factors on assembled buildings."

③Based on your suggestions, the authors have added six experts in their fields and experience. Please check the fourth paragraph of Section 3.1."All six experts have master's degrees and above. Among them, four scholars are engaged in research related to assembled buildings and have a better understanding of the local development of assembled buildings. Two industry practitioners are engaged in structural technology of prefabricated buildings and have published several patents, and have a better understanding of the existing problems of prefabricated buildings."

You can see the attachment for the revised paper.

Author Response File: Author Response.pdf

Reviewer 2 Report

The paper is of high interest to both researchers and potentially practitioners. The way it was presented, however is highly theoretical and can only be of potential interest to scholars. Even then, the discussion, though it established some sort of a hierarchy for the influencing factors, the  effect of each of these factors is still expressed in a generic form. For instance to say "Therefore, the type, connection method and construction process of the assembled components need to be clarified in the design stage to ensure the smooth-ness of the subsequent stages." is not very beneficial to the designer or the manufacturer. If at all possible, some clarifications regarding the discussion of the Four major factors would enhance the quality of the paper.

Further comments regarding the text can be founded embedded in the attached PDF file.

Author Response

Here are our changes.

Comment: The paper is of high interest to both researchers and potentially practitioners. The way it was presented, however is highly theoretical and can only be of potential interest to scholars. Even then, the discussion, though it established some sort of a hierarchy for the influencing factors, the effect of each of these factors is still expressed in a generic form. For instance to say "Therefore, the type, connection method and construction process of the assembled components need to be clarified in the design stage to ensure the smoothness of the subsequent stages." is not very beneficial to the designer or the manufacturer. If at all possible, some clarifications regarding the discussion of the Four major factors would enhance the quality of the paper.

Response: Thank you for this suggestion. Specific clarifications regarding the discussions of the major factors have been added in Section 5.2. As one example, a detailed suggestion for the local government and the construction enterprises to address the "employee" factor has been added in the revised manuscript, as the following: "For example, the local government can organize training sessions to clarify and unify design principles and industrial standards and specifications, whereas construction organizations should timely hold workshops or seminars to facilitate internal experience sharing and technical exchange among designer professionals. "

Moreover, detailed strategies for the improvement of the prefabrication process have been summarized and added in the Conclusions Section, which suggest exactly how organizations from the designer, contractor, and prefabricated component manufacturer sides can work more efficiently to address the identified critical factors in prefabrication projects. For example, the following statements have been added in the Conclusion Section: "To ensure prefabricated components meet production standards, production enterprises should introduce information technology management systems such as BIM to better tailor for the specific needs of the prefabrication process, which can offer effective inventory management, quality control, and precise progress management. In addition, standardized raw material ratios and component maintenance systems should be established, which can provide accurate maintenance records (e.g., time and personnel) to ensure the traceability and consistency of maintenance work. "

You can see the attachment for the revised paper.

Author Response File: Author Response.pdf

Reviewer 3 Report

The study analyzes the Factors Affecting Prefabricated Building Quality Based on ISM-BN. GeNIe software and questionnaires are used for this study. Moreover, the parameters are taken by performing a literature review of locally and internationally published work. The use Prefabricated structures and buildings is widespread, and this technology is becoming more useful in farther areas or during the disasters. 

In this paper, there are a few questions to be addressed. Please find my comments below: 

-There are no line numbers in the paper. Therefore, it makes difficult to refer to a specific line/ argument present in a the paper.

-The authors have mentioned questionnaire as a method of data collection from the experts. However, at certain points interview or discussion with the experts is mentioned. Please clarify, which tools were used. Moreover, be consistent on the methods used to avoid any confusions. 

-According to Fig. 1. The data was collected using interviews. The questionnaire method or discussion is not mentioned. 

-Six persons were interviewed? How was the interview questionnaire structured? How these experts were selected?

-What do you mean by discussion with experts? Was it a focus group or just one on one meeting? 

-Equations 1-6, the authors have devised these equations or taken from another source? validation of these equations must be added. 

-Section 3.2: There is discussion of questionnaire that used a Likert scale response. How many questionnaires were distributed? 136 questionnaires were valid after the completion of survey. What was the reason that made the rest of questionnaires invalid? 

-8y of work experience is considered as a reliable parameter. Was this experience of the majority was based in the same field/ type of work?

-Explain Figure 3. What represents values denoted with T, P and C. Same comments for Fig 4, 5 and 6.

-Most of the figures are unclear and not readable. 

-Add legends in the Tables.

-What is the validation of the model? Discuss. 

-Discuss, how the sensitivity analysis was performed?

Minor changes are required. 

Author Response

Here are our changes.

1.Comment: There are no line numbers in the paper. Therefore, it makes difficult to refer to a specific line/ argument present in the paper.

Response: Thank you for this comment. We have added line numbers in the revised manuscript following your suggestion.

2.Comment: The authors have mentioned questionnaire as a method of data collection from the experts. However, at certain points interview or discussion with the experts is mentioned. Please clarify, which tools were used. Moreover, be consistent on the methods used to avoid any confusions.

Response: Thank you for the suggestions. We provide the following clarification on the application of the methodology. After the initial screening of factors using relevant literature, six experts were found to conduct one-on-one interviews in this study to supplement the screened factors. To determine whether there is a direct relationship between the factors, six experts were found to conduct one-on-one interviews, and the format of the questionnaire has been posted in the Appendix, and the judgment method is in Section 3.3. After establishing the basic structure of the model, the parameters of the Bayesian network nodes needed to be judged, so questionnaires needed to be distributed and found to be filled out by people involved in the construction of prefabricated buildings.

3.Comment: According to Fig. 1. The data was collected using interviews. The questionnaire method or discussion is not mentioned.

Response: Thank you for this comment. Based on your suggestion, we have added a detailed description to the first paragraph of section 2.1. A general description of the expert interviews and questionnaires in the text were given.

4.Comment: Six persons were interviewed? How was the interview questionnaire structured? How these experts were selected?

What do you mean by discussion with experts? Was it a focus group or just one on one meeting?

Response: Thank you for the important questions. A total of six individual interviews were conducted with experts in the construction field.

The sample selection criteria have been added in Section 3.2 of the revised manuscript, as the following: "The criteria for the selection of the samples include: (1) they must be academics, engineers, or managers who have hands-on working experience in prefabricated construction projects; and (2) they must have experienced at least one prefabricated building project within the last three years and be familiar with the recent development of prefabricated buildings. "

In determining the factors, six experts were identified for one-on-one interviews in this study, and the format of the questionnaire is shown in Table A 1. In determining whether there is a direct relationship between the factors, six experts were also identified for one-on-one interviews in this study, and the format of the questionnaire is shown in Table A 2. The experts selected had certain criteria, and had to have a master's degree or higher and have been working in assembly construction or research for many years. We have explained about the experts' background in the fourth paragraph of Section 3.1 and the first paragraph of Section 3.3.1.

5.Comment: Equations 1-6, the authors have devised these equations or taken from another source? validation of these equations must be added.

Response: Thank you for the suggestion. We have added the origin of the formulas and methods in the first paragraph of Section 2.2, as the following: "Warfield, an American scholar, proposed the method of establishing an interpretive structural mode, which is referred to as the ISM method. It aims to convert a vague or undefined model into a clearly defined model, so that a more complex system includes a fundamental factor layer, an indirect factor layer and a direct factor layer can be constructed[19]. Bayesian network, abbreviated as BN, was proposed by American scholar Pearl in 1988 as a directed acyclic graph consisting of arcs and nodes[21]. The ISM-BN model of the quality factors of PC buildings was developed in five steps. "

6.Comment: Section 3.2: There is discussion of questionnaire that used a Likert scale response. How many questionnaires were distributed? 136 questionnaires were valid after the completion of survey. What was the reason that made the rest of questionnaires invalid?

Response: Thank you for the questions. A total of 160 questionnaires were distributed, among which 136 were valid questionnaires. Some responses that had extreme response bias (i.e., participants repeatedly choose an extreme answer value to answer a question in a questionnaire survey) were considered invalid and thus excluded from the data collected. They have been added in Section 3.2 of the revised manuscript.

7.Comment: 8y of work experience is considered as a reliable parameter. Was this experience of the majority was based in the same field/ type of work?

Response: Thank you for the important question. We can confirm that their years of work and experience are based on the same field of work.

8.Comment: Explain Figure 3. What represents values denoted with T, P and C. Same comments for Fig 4, 5 and 6.

Response: Thank you for the questions. To avoid confusion, we have added the following note in Section 3.3.2 of the revised manuscript: "D represents quality problems in the design stage, P represents quality problems in the production stage of prefabricated components, T represents quality problems in the transportation stage, C represents quality problems in the construction stage, and Q represents quality problems in prefabricated buildings. "

9.Comment: Most of the figures are unclear and not readable.

Response: Thank you for the comment. Based on your suggestion, we have made the figures clearer and more readable and made sure that each figure has a separate page.

10.Comment: Add legends in the Tables.

Response: Thank you for the suggestion. We checked the whole paper, and the legends that cannot be missing during the analysis have all been posted in the appendix due to the excessive space they occupy.

11.Comment: What is the validation of the model? Discuss.

Response: Thank you for the question. The validation of the model through a case project in Nantong has been provided in Section 5.2 and the first paragraph of Section 6, which suggests that the case study results are generally consistent with the ISM-BN model, validating the applicability of the model to general prefabricated building projects.

12.Comment: Discuss, how the sensitivity analysis was performed?

Response: Thank you for the suggestion. An explanation of how the sensitivity analysis was performed has been added in Section 4.3 in the revised manuscript, as the following: "In Bayesian network graphs, dark nodes are usually used to indicate variables with high sensitivity, while lighter nodes indicate variables with lower sensitivity. “

A marked copy of the manuscript including the detailed revision track record is attached for your kind reference.

You can see the attachment for the revised paper.

Author Response File: Author Response.pdf

Round 2

Reviewer 3 Report

Dear authors,

Thanks for making the necessary changes in the revised version.  I checked the response letter and updated the manuscript. 

The paper can be accepted in the present form.