Influence of Age on the Technical Wear of Tenement Houses

Round 1

Reviewer 1 Report

The paper discusses a very interesting topic in engineering.

It illustrates solutions concerning the problems of the technical maintenance and wear of residential buildings with traditional construction.

The cause and effect relationships between the occurrence of damage in the elements of tenement houses and the size of the technical wear of these elements were determined using a representative sample of 102 residential buildings.
Quantitative damage analysis, which was carried out using empirical methods of assessing the technical condition of a building, indicates the type and size of damage to the building's elements that are characteristic for the relevant maintenance conditions.

This reviewer believes that the paper is well presented and the results are consistent. Then the paper can be published in the present form.

 

As described in the review report I think that the paper is exhaustive and well presented. Also, the introduction of the paper cites several papers that refer to the topic treated.

The paper can be published in the present form.

 

Author Response

Wrocław, Poland, 22^nd December 2020

Dear Mrs. Eleven Wei, M.Sc. Assistant Editor –  MDPI,

Dear Editorial Board of Applied Sciences,

Thank you for the review of our paper applsci-1048256 entitled “Influence of Age on the technical Wear of Tenement Houses” to be published in the Journal “Applied Sciences”.

We appreciate  thoughtful and  accurate comments presented by the reviewers as well as appreciation of our research works. We have carefully considered a few remarks and have now completed the revisions incorporating  their suggestions in the revised uploaded manuscript.

We hope that we have taken constructive comments into account in the revised  paper. We also hope that the final version meets your expectations.

Kind regards,

Jarosław Konior, Marek Sawicki and Mariusz Szóstak

Department of Building Engineering, Faculty of Civil Engineering, Wroclaw University of Science and Technology, 50-370 Wrocław, Poland

  

Here are answers to reviewer’s comments:

ANSWERS TO REVIEWERS’ 1, 2, 3

1. The quality of all figures (fonts, resolution, comprehensiveness) has been improved.
2. Indeed, the influence of repairs on the technical wear and service life of the building were not assessed as the entire maintenance of tenement houses is a separate significant topic and cannot be included in the paper of 23 pages content yet. It is absolutely agreed that the proper maintenance is decreasing the technical wear degree and expanding service life as presented in the example figure – the trend is decreasing within durability period, only after a repair is temporary increasing.
3. The references No. 57-64 regarding statistical methods represent the first issues of the considered books. Updated submissions or equivalent references have been exchanged in the revised paper.

Author Response File: Author Response.pdf

Reviewer 2 Report

I read a very well written manuscript. The methodology is very well explained and easy to reproduce/replicate in case of interest. The ideas flow fluently. 

The only suggestion I have is to improve the quality of figures.

 

Author Response

Wrocław, Poland, 22^nd December 2020

Dear Mrs. Eleven Wei, M.Sc. Assistant Editor –  MDPI,

Dear Editorial Board of Applied Sciences,

Thank you for the review of our paper applsci-1048256 entitled “Influence of Age on the technical Wear of Tenement Houses” to be published in the Journal “Applied Sciences”.

We appreciate  thoughtful and  accurate comments presented by the reviewers as well as appreciation of our research works. We have carefully considered a few remarks and have now completed the revisions incorporating  their suggestions in the revised uploaded manuscript.

We hope that we have taken constructive comments into account in the revised  paper. We also hope that the final version meets your expectations.

Kind regards,

Jarosław Konior, Marek Sawicki and Mariusz Szóstak

Department of Building Engineering, Faculty of Civil Engineering, Wroclaw University of Science and Technology, 50-370 Wrocław, Poland

  

Here are answers to reviewer’s comments:

ANSWERS TO REVIEWERS’ 1, 2, 3

1. The quality of all figures (fonts, resolution, comprehensiveness) has been improved.
2. Indeed, the influence of repairs on the technical wear and service life of the building were not assessed as the entire maintenance of tenement houses is a separate significant topic and cannot be included in the paper of 23 pages content yet. It is absolutely agreed that the proper maintenance is decreasing the technical wear degree and expanding service life as presented in the example figure – the trend is decreasing within durability period, only after a repair is temporary increasing.
3. The references No. 57-64 regarding statistical methods represent the first issues of the considered books. Updated submissions or equivalent references have been exchanged in the revised paper.

Author Response File: Author Response.pdf

Reviewer 3 Report

The paper is interesting from practical application, but from scientific point not all factors are evaluated- influence of repairs on the technical wear and service life of the building were not assessed. The proper maintenance is decreasing the technical wear degree and expanding service life (durability) (see attached file).

Some literature sources in manuscript are providing information about second half of the nineteenth and early twentieth centuries in Wroclaw's "Downtown" district, so they are quite old and this is correct, but for statistical methods mentioned in reference list No.57-64 should be used newer literature sources.

Quality of Fig.3 should be improved.

Comments for author File: Comments.pdf

Author Response

Wrocław, Poland, 22^nd December 2020

Dear Mrs. Eleven Wei, M.Sc. Assistant Editor –  MDPI,

Dear Editorial Board of Applied Sciences,

Thank you for the review of our paper applsci-1048256 entitled “Influence of Age on the technical Wear of Tenement Houses” to be published in the Journal “Applied Sciences”.

We appreciate  thoughtful and  accurate comments presented by the reviewers as well as appreciation of our research works. We have carefully considered a few remarks and have now completed the revisions incorporating  their suggestions in the revised uploaded manuscript.

We hope that we have taken constructive comments into account in the revised  paper. We also hope that the final version meets your expectations.

Kind regards,

Jarosław Konior, Marek Sawicki and Mariusz Szóstak

Department of Building Engineering, Faculty of Civil Engineering, Wroclaw University of Science and Technology, 50-370 Wrocław, Poland

  

Here are answers to reviewer’s comments:

ANSWERS TO REVIEWERS’ 1, 2, 3

1. The quality of all figures (fonts, resolution, comprehensiveness) has been improved.
2. Indeed, the influence of repairs on the technical wear and service life of the building were not assessed as the entire maintenance of tenement houses is a separate significant topic and cannot be included in the paper of 23 pages content yet. It is absolutely agreed that the proper maintenance is decreasing the technical wear degree and expanding service life as presented in the example figure – the trend is decreasing within durability period, only after a repair is temporary increasing.
3. The references No. 57-64 regarding statistical methods represent the first issues of the considered books. Updated submissions or equivalent references have been exchanged in the revised paper.

Author Response File: Author Response.pdf

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

See attached file.

Comments for author File: Comments.pdf

Author Response

Wrocław, Poland, 18^th November 2020

 

Dear Mrs. Eleven Wei, M.Sc. Assistant Editor –  MDPI,

Dear Editorial Board of Applied Sciences,

 

Thank you for the review of our paper applsci-980626 entitled “Influence of Age on the technical Wear of Tenement Houses” to be published in the Journal “Applied Sciences”.

First of all, we appreciate your  thoughtful and  accurate comments presented by the reviewers. We have carefully considered all remarks and have now completed the revisions incorporating  their suggestions in the revised uploaded manuscript.

We hope that we have taken all your critical and constructive comments into account in the revised  paper. We also hope that the current version meets your expectations.

 

Kind regards,

 

Jarosław Konior, Marek Sawicki and Mariusz Szóstak

Department of Building Engineering, Faculty of Civil Engineering, Wroclaw University of Science and Technology, 50-370 Wrocław, Poland

 

 

Here are answers to reviewer’s comments – one by one:

 

 

REVIEWER 1

 

The research presented in the proposed article, concern the problem of the technical maintenance and wear of residential buildings with a traditional construction. A sample of 102 residential buildings in Wroclaw’s downtown district have been surveyed and a complete evaluation of the technical conditions of a wide set of different elements has been performed. A mathematical approach is proposed and discussed. In general, the proposed paper is well written and the structure is correct, although some details, regarding the order and tittle of the sections, should be revised (see comments below). Nevertheless, in this reviewer opinion, the conclusions are not sufficiently justified (see comments below) and a depth work on the survey results should be done in order to reach clearer conclusions.

 

Observations and Comments:

 

Comment 1. General. Review the page numbers. For example, the page 11 appears as “3 of 21”.

Answer 1. Page numbering broken when a landscape layout was introduced. Corrected now.

 

Comment 2. Line 23. Please review “The exploitation condition of this building is manifested by.. “ May be “these buildings” instead of “this building”.

Answer 2. Plural form “these buildings” incorporated accordingly.

 

Comment 3. Lines 118 and 119. “ .. technical wear is a function of time t in the assumed durability… building object T”. It may be more convenient to write in italic the variables “t” and “T”. At this respect, please review the template and guidelines to authors in the web page of the journal.

Answer 3. All variables that appear in the body of the paper were converted to Italic and now they correspond to the Italic ones that appear in the formulas.

 

Comment 4. Line 195. In Table 1. The research sample covered 102 technically assessed residential buildings. In the table, the total number of analyzed apartment houses differs from 102 in some columns (95 and 99 in two and one column respectively). May the authors explain these differences?

Answers 4. All 102 tenement houses constitute one integrated typological research sample but as regard walls of basement and solid floors over basement 7 of them were ground compacted by the stabilized cement internally after a Second World War, therefore not possible to assess technically; also 3 facades were completely changed into new repair plastering, therefore excluded from the research analyses.

 

Comment 5. Lines 200-217. The authors explain the trends of different statistical parameters related to a set of 10 technically examined elements (selected from the initial group of 23 elements). I suggest including a Table summarizing these parameters. This will made clearer, for the reader, to understand the trend of the variability of each analyzed element.

Answer 5. As indicated in the line 201 from the group of 23 technically examined elements, the 10 elements with the highest share in the building (65% in total) were selected for further analysis. The new pie chart was introduced for better understanding of the analysed elements selection.

 

Comment 6. Line 218. It may be interesting to include information about: 1) who were the experts (competences); 2) How many experts were involved in the measurements; 3) How many time it took to gather all the information and measurements. This kind of information should help the reader to approach the practical part of this assessment: how many people and how much time are needed in this kind of studies.

Answer 6. The group of experts consisted of:

• 1 architect
• 1 structural engineer
• 1 mechanical / sanitary engineer
• 1 electrical engineer
• 2 quantity surveyors
• 1 technician / administrator

The average workload needed for the technical assessment of each tenement houses has been calculated as follows:

• desk top study of multidiscipline design and archive documents  - 2 days for 5 people
• technical investigations and surveys – 3 days for 7 people
• generating calculations and reports - 2 days for 5 people

The above information was inserted in the text.

 

Comment 7. Line 248. Authors refer to “.. four-level classification at the level of general synthesis –Table 2.” In Table 2 the authors refer to “four groups” of defects. It may be appropriate to refer, in the main text (Line 248) to “groups” instead to “levels”.

Answer 7. Changed from “four-level” to “four-group” classification and now it is more comprehensive.

 

Comment 8. Lines 249-254. Please improve the explanation. The paragraph is not clear.

Answer 8. Changed in more clear way: It must be remembered however that generically integrated elementary damage is separated therefore their total number is 30. There is also a very important assumption made, according to which damage is described using number 1 (appear), and its lack using 0 (not apper). This is due to the fact that the group of experts only identified damage in the analysed buildings that is independent of their natural wear i.e. that which occurs to a great extent. They were describing it with clear and decisive qualitative features [52]: "significant", "very strong", "strong", "total", etc.

 

Comment 9. Lines 253 and 254. Please clarify if it is possible to define a relationship between the qualitative features: “significant, very strong, strong, total, etc.” and the classes of technical wear in Table 1.

Answer 9. The problem is that there is not such association of descriptive qualitative features with the classes of technical wear available in the accessible literature. The experts – at technical investigation of the buildings – assess the technical wear of the element as result of quantitative / measurable defects altogether with qualitative appraisal such as “significant, very strong, strong, total, etc.”. This is why their assessment is to some extent subjective and we made a point to calculate what part of technical wear is explained by the passage of time which is definitely non-subjective feature.

 

Comment 10. Lines 324 and 325. Please review the font style (italic) of your variables. See comment above (lines 118 and 119).

Answer 10. All variables that appear in the body of the paper were converted to Italic and now they correspond to the Italic ones that appear in the formulas.

 

Comment 11. Line 342 (and in Line 254). Avoid the use of ”.., etc.”. Instead, authors should use sentences like “.., among others aspects.” Or other similar alternatives.

Answer 11. Corrected as indicated.

 

Comment 12. Line 433. The mathematical models are not new math models. I suggest to refer this models as proposed models: “From the four proposed mathematical models,..”

Answer 12. Indeed, these are not new mathematical models. Changed as suggested.

 

Comment 13. Lines 413, caption of Fig. 1 and Line 418. Reading the text, in Line 418 it can be inferred that the “exemplary analyzed element “ is the “conditions of stairs”. Please include in the caption of Fig.1 and in Line 413 the specific reference to the element “conditions of stairs”

Answer 13. Changed as indicated: inter-storey stairs = inner staircase

 

Comment 14. Lines 432 and 446. Please include capital letters at the beginning: “a. Regarding mathematical..” and “b. Regarding the analysis..”

Answer 14. Changed as requested.

 

Comment 15. Line 436 and Line 460. Type mismatch: the coefficient of determination is “R²” and not “R2”

Answer 15. Coefficient of determination changed to R² symbol in entire text

 

Comment 16. Line 437. Review the expression: Zt= F(T).

Answer 16. Corrected as stated in the text: Zt = f(T) which means theoretical technical wear function

 

Comment 17. Line 443, Table 3 and Lines 467-468. The results, regarding the coefficient of determination R, are very poor and this difficult any interpretation about the quality of the adjustment concerning the data and the proposed models.

Answer 17. The low values of the coefficient determination R² do not mean that the results are poor (!). It only means that that no more than 30% of the damage of elements is explained by the passage of time. Therefore, it is not age that determines the course of the technical wear of the analysed building elements. What may be doubtful are theoretical methods for measuring the technical wear and tear of the buildings which do not reflect the actual course of the deterioration process over time. An assessment of the significance of the differences between the theoretical and observed technical consumption distribution values of building elements by Wilcoxon test and the Sign Test in most cases confirmed the conclusions of their comparative analysis and showed the significance of the differences between the distributions of theoretical and observed wear, although the Sign Test indicated their identity in the case of foundation distributions, underground walls and structural walls in the all five conditions of maintenance, while both  Wilcoxon test and the Sign Test confirmed the identity of the distributions only in individual maintenance groups of the buildings – see more [28,31,32,40,41,62].

 

Comment 18. Line 467-468. I suggest modifying the sentence: “..in the nonlinear regression method indicates that, in some specific building elements and with the proposed mathematical models, at best no more than 30% of the damage of elements is explained by the passage of time.”

Answer 18. Modified as suggested.

 

Comment 19. Line 468-469. I suggest modifying the sentence: “Therefore, with the proposed mathematical models, it seems that the age does not determines completely the course of the technical wear of the analyzed building elements.”

Answer 19. Modified as suggested.

 

Comment 20. 3. Conclusions and 4. Summary and discussion. I suggest reviewing the tittle and order of these two sections. Please review the guidelines for authors in the journal webpage: https://www.mdpi.com/journal/applsci/instructions

Answer 20. Title of Conclusions was deleted. Results and findings were drawn and interpreted in Discussion section. A brief Summary was introduced in the end of the paper.

 

Comment 21. 3. Conclusions and 4. Summary and discussion. Line 470. The authors state, “The degree of the technical wear of the elements of an old residential building is determined by the conditions of its maintenance and use.” In this revision, it is quite difficult to understand how the authors reach this conclusion. The mathematical elements of this study do not lead to this conclusion. Probably, the obtained results during the onsite survey of the buildings, should be analyzed and discussed in depth in order to justify more clearly the conclusions regarding the conditions of maintenance and use and their influence on the technical wear.

Answer 21. Indeed, conclusions regarding the conditions of maintenance and use and their influence on the technical wear are not supported by research presented here. They come from our previous works. However, the conclusion „b” (the degree of the technical wear of the elements of an old residential building is determined by the conditions of its maintenance and use) supplements the statement that “it is not age that determines the course of the technical wear of the analysed building elements”. Two sub-conclusions in bullets that comes below are from our previous works and should not have been presented in the paper, so were deleted.

Author Response File: Author Response.pdf

Reviewer 2 Report

This manuscript touches on an important topic. My main issue is that the structure of the paper is very poor and does not represent a scientific research paper. At this stage, I would have to reject this manuscript unless a significant improvement is made to the structure of the manuscript. For example, the introduction is too long and starts with a sub-title of "identification of the problem", then it is not clear what is covered in the literature survey section, the Discussion section has come after the conclusion, there are so many bullet points, etc. 

Author Response

Wrocław, Poland, 18^th November 2020

 

 

Dear Mrs. Eleven Wei, M.Sc. Assistant Editor –  MDPI,

Dear Editorial Board of Applied Sciences,

 

Thank you for the review of our paper applsci-980626 entitled “Influence of Age on the technical Wear of Tenement Houses” to be published in the Journal “Applied Sciences”.

First of all, we appreciate your  thoughtful and  accurate comments presented by the reviewers. We have carefully considered all remarks and have now completed the revisions incorporating  their suggestions in the revised uploaded manuscript.

We hope that we have taken all your critical and constructive comments into account in the revised  paper. We also hope that the current version meets your expectations.

 

Kind regards,

 

Jarosław Konior, Marek Sawicki and Mariusz Szóstak

Department of Building Engineering, Faculty of Civil Engineering, Wroclaw University of Science and Technology, 50-370 Wrocław, Poland

 

 

Here are answers to reviewer’s comments – one by one:

 

 

REVIEWER 2

 

This manuscript touches on an important topic. My main issue is that the structure of the paper is very poor and does not represent a scientific research paper.

 

Comment 1. At this stage, I would have to reject this manuscript unless a significant improvement is made to the structure of the manuscript.

Answer 1. The structure of the manuscript has been significantly improved.

 

Comment 2. For example, the introduction is too long and starts with a sub-title of "identification of the problem", then it is not clear what is covered in the literature survey section.

Answer 2. Literature survey with the key publications cited appears throughout entire Introduction which was shortened as much as possible. Both sub-titles were removed in the Introduction paragraph. However the Introduction still briefly placed the study in broader context and highlighted its importance.

 

Comment 3. Discussion section has come after the conclusion, there are so many bullet points, etc. 

Answer 3. Title of Conclusions was deleted. Results and findings were drawn and interpreted in Discussion section. A brief Summary was introduced in the end of the paper.

Author Response File: Author Response.pdf

Reviewer 3 Report

In the substance, this paper is interesting and corresponds to the intended special issue. In the form, some text improvements are needed and some methodological aspects have to be better described.

Some sentences are difficult to understand and the text would gain in clarity if some of them will be rewrite more simply. We suggest to authors to try to simplify their sentences. To help readers, we also suggest to add some pictures in section 2 to illustrate some elements and their degrees of wear.

Other Corrections / Suggestions /Questions :

-line 101 : at this step of reading, it is impossible to understand what is this 3-level division of wear. Please, give more explanations.

-lines 176-177 : "It contains all ... in this study". This is an example of sentence which is difficult to understand. Please, give explanations.

-line 202 to 205 : please, explain for readers how are calculated values between brackets.

-line 243-244 : please explain better why you have to consider that renovation of these 15 objects could be ineffective (on which argument ?)

-line 245 : be careful about the numbering of section which is wrong from this point and the following.

Here, I must admit that from section '2.4 Accelerated wear' to the end of section 2, this part is very difficult to read and understand even in its substance. Substantial efforts are required to improve significantly this part.

-line 249 : what is this number 30 ?

-line 250-251 : what are these numbers 1 and 0 ? To what are they referred ?

-line 253-254 : I don't understand where are used in the text the features "significant", ..., "total", etc...

-Table 2 : It is difficult for me to understand how are used data within Table 2 in your research method. 

-line 322 : the idea to associate null hypothesis to linear regression is convenient. But, since this part is essential to the understanding of the method used, authors should take more time to present better and simply these crucial points. May be use of a flowchart would be helpful.

-line 336 : what are ξ1, ξ2, ... ξk ? k index ?

-lines 338 to 342 : be more explicit, please, by providing examples of factors.

-line 365, please put B at the exponent.

-Figure 1 : there is not enough details to understand how figures 1 are drawn and, above all, how the maintenance quality has an effect on these figures. You should also draw c(ξ) in figures 1.

-line 419-422 : What do you lean by popular parabolic model ? Do you use it ? Where ?

-line 424 : you should explain if you pretreat data before to carry out ANOVA (especially in the cases of power and exponential models)

-Table 3 : May be you can complete this table with some graphs drawing observations vs models for the different elements.

-line 428 : Choose another title for section 3 instead of 'conclusions'

-line 470-479 : I don't understand where these conclusions come from. Are they introduced before ?

Author Response

Wrocław, Poland, 18^th November 2020

 

 

Dear Mrs. Eleven Wei, M.Sc. Assistant Editor –  MDPI,

Dear Editorial Board of Applied Sciences,

 

Thank you for the review of our paper applsci-980626 entitled “Influence of Age on the technical Wear of Tenement Houses” to be published in the Journal “Applied Sciences”.

First of all, we appreciate your  thoughtful and  accurate comments presented by the reviewers. We have carefully considered all remarks and have now completed the revisions incorporating  their suggestions in the revised uploaded manuscript.

We hope that we have taken all your critical and constructive comments into account in the revised  paper. We also hope that the current version meets your expectations.

 

Kind regards,

 

Jarosław Konior, Marek Sawicki and Mariusz Szóstak

Department of Building Engineering, Faculty of Civil Engineering, Wroclaw University of Science and Technology, 50-370 Wrocław, Poland

 

 

Here are answers to reviewer’s comments – one by one:

 

REVIEWER 3

 

In the substance, this paper is interesting and corresponds to the intended special issue. In the form, some text improvements are needed and some methodological aspects have to be better described.

 

Comment 1. Some sentences are difficult to understand and the text would gain in clarity if some of them will be rewrite more simply. We suggest to authors to try to simplify their sentences.

Answer 1. We – as researchers – find the topic and its description pretty easy and universe (housing) all over the world. Where possible we simplified the meaning we would like to put across.

 

Comment 2. To help readers, we also suggest to add some pictures in section 2 to illustrate some elements and their degrees of wear.

Answer 2. Due to limited body of the paper we introduced the picture of the oldest, dating back to the year 1818, analysed tenement house for the reference. It is not possible to present bulk of pictures showing the detected defects of investigated the hundreds of building elements.

 

Other Corrections / Suggestions /Questions:

 

Comment 3. -line 101: at this step of reading, it is impossible to understand what is this 3-level division of wear. Please, give more explanations.

Answer 3. There are various criteria for assessing the degree of wear of an object published in English and German literature which adopt a three-level division at a general level (0-30%, 31-70% and 71-100%) whereas in Poland a five-stage classification is recommended as indicated in the table 1.

 

Comment 4. -lines 176-177: "It contains all ... in this study". This is an example of sentence which is difficult to understand. Please, give explanations.

Answer 4. Indeed, this information is not necessary and therefore misleading. Two sentences in lines 176 – 179 were deleted.

 

Comment 5. -line 202 to 205 : please, explain for readers how are calculated values between brackets.

Answer 5. The technical wear degree of these elements has been calculated theoretical way as a function Zt = f(T) [39, 46-51] and as a result of building’s technical inspections executed by engineering experts.

 

Comment 6. -line 243-244 : please explain better why you have to consider that renovation of these 15 objects could be ineffective (on which argument ?)

Answer 6. In the group of 102 assessed objects, there are nine buildings in which a significant destruction of all the distinguished elements was observed, and six buildings in which the destruction concerned four out of five analysed elements. Therefore, it can be briefly concluded that the renovation of 15 (9 + 6) objects in the group of 102 could be technically ineffective.

 

Comment 7. -line 245 : be careful about the numbering of section which is wrong from this point and the following.

Answer 7. Indeed it is wrong; numbering of sections from item 2.3 was corrected.

 

Comment 8. -line 249 : what is this number 30?

Answer 8. Elementary damage is separated, which increases their number to 30; this means that there are 30 pinpointed damages presented in the table 2

 

Comment 9. -line 250-251 : what are these numbers 1 and 0 ? To what are they referred ?

Answer 9. Detected defect is described using number 1 (appears), and its lack using 0 (does not appear). Numbers 1 and 0 are dichotomic variables.

 

Comment 10. -line 253-254 : I don't understand where are used in the text the features "significant", ..., "total", etc...

Answer 10. Qualitative features "significant", "very strong", "strong", "total", etc. are not used in the text any more. They were mentioned at the end of the paragraph 2.3 only to confirm some subjectivity of experts investigations, e.g. “1 x weeping + significant”

 

Comment 11. -Table 2 : It is difficult for me to understand how are used data within Table 2 in your research method. 

Answer 11. Table 2 shows the list  / classification of pinpointed defects relevant to the investigated elements (mark # if the defect appears) and split into 4 groups of damages. These defects represent the maintenance conditions of the tenement houses.

 

Comment 12. -line 322 : the idea to associate null hypothesis to linear regression is convenient. But, since this part is essential to the understanding of the method used, authors should take more time to present better and simply these crucial points. May be use of a flowchart would be helpful.

Answer 12. Nonlinear regression with null hypothesis H0 stands for basics at any technical university; we do not feel as appropriate to present basics in more deeper way than in lines 318 - 369

 

Comment 13. -line 336 : what are ξ1, ξ2, ... ξk ? k index ?

Answer 13. ξ1, ξ2, ... ξk are the elementary components of the random constant ξ which includes the factors of the two-type influence:

• reference to the maintenance conditions of downtown residential buildings and the subjectivity of their technical assessment by each of the adjudicating experts;
• reference to the type of measuring equipment and measurement errors the used technical assessment method and its accuracy, the incomplete knowledge about the technical condition, and the age of the tested element.

 

Comment 14. -lines 338 to 342 : be more explicit, please, by providing examples of factors.

Answer 14. Examples given above – there are all random components also including inappropriate use by inhabitants, negligence of major repairs, lack of archive documentations of buildings, etc.

 

Comment 15. -line 365, please put B at the exponent.

Answer 15. Done.

 

Comment 16. -Figure 1 : there is not enough details to understand how figures 1 are drawn and, above all, how the maintenance quality has an effect on these figures. You should also draw c(ξ) in figures 1.

Answer 16. Both [d(x)]² and c(x) are to control the correctness of the trend function selection is crucially important for the analysis of the expected life of building elements. Assuming the expected time of an apartment house exploitation to be an independent variable T, a course of relationship of the remainder addends and their deviations average was tested as a function of the expected life: [d(x)]²=f(T) and c(x)=f(T). In a correctly constructed model, the variance [d(x)]² should reach the minimum for values of the expected life (T*=120 years) quoted in literature and the average deviation should be close to zero  c(x). However, depending on the stairs maintenance conditions, both the c(x) assumes zero values, and the  [d(x)]² reaches the minimum for the real/observed expected life T** that amounted to 178, 160 and 157 years - figure 3. The expected life of 10 selected apartment houses elements was thus analysed for a twofold trend function, i.e.: for popular parabolic models and for one of models searched for with a considerable measure of matching (significant determination coefficient  R²).

Mean of deviations of residuals c(ξ) figure added accordingly.

 

Comment 17. -line 419-422 : What do you lean (mean?) by popular parabolic model ? Do you use it ? Where ?

Answer 17. Theoretical technical wear is described by well known formulas representing parabolic models:

  

 Those were tested in the previous works and proofed incompatibility of the real / observed state. This was brachylogy, corrected now in the paper.

 

Comment 18. -line 424 : you should explain if you pretreat data before to carry out ANOVA (especially in the cases of power and exponential models)

Answer 18. We do not pretreat any data for any model before carrying out analysis of variance.

 

Comment 19. -Table 3 : May be you can complete this table with some graphs drawing observations vs models for the different elements.

Answer 19. Presented results in the table 3 are self-explanatory. A set of different graphs may supplement observations vs models; as to present determination coefficients R² only is 10 drawings, so we would like not to extend the paper but if there is such confirmed need we will do so.

 

Comment 20. -line 428 : Choose another title for section 3 instead of 'conclusions'

Answer 20. Title of Conclusions was deleted. Results and findings were drawn and interpreted in Discussion section. A brief Summary was introduced in the end of the paper.

 

Comment 21. -line 470-479 : I don't understand where these conclusions come from. Are they introduced before ?

Answer 21. The conclusion „b” (the degree of the technical wear of the elements of an old residential building is determined by the conditions of its maintenance and use) supplements the statement that “it is not age that determines the course of the technical wear of the analysed building elements”. Two sub-conclusions in bullets that comes below are from our previous works and should not have been presented in the paper, so were deleted.

Author Response File: Author Response.pdf

Round 2

Reviewer 3 Report

Dear authors,

I thank you for the change you have give to your initial submission. I still require some small changes:

• line 202 : at least, give just one time, the detail of calculation of numbers within brackets. Add the detail of the calculation of (56.77% = 5 x 8 + 17 x ...+28 x...).
• lines 243-4 : I had understood where the number of 15 objects came from, but I was not sure to understand the conclusion about the ineffectiveness of renovation. Here, for these "very affected" objects, do you consider that they so damaged that the only alternative is to demolish them ?
• Table 2 : I had also understood main meaning of this Table, but my concern was how this list is used for the following steps. There is no direct visible link between this Table and the modeling.
• Table 3 : I strongly suggest to complete this Table adding graphs for cases Z2 and Z20, as examples.

Author Response

Wrocław, Poland, 24^th November 2020

 Dear Mrs. Eleven Wei, M.Sc. Assistant Editor –  MDPI,

Dear Editorial Board of Applied Sciences,

 

Thank you for the review of our revised paper applsci-980626 entitled “Influence of Age on the technical Wear of Tenement Houses” to be published in the Journal “Applied Sciences”.

We appreciate thoughtful and  accurate comments presented by the reviewers. We have carefully considered all remarks and have now completed the revisions incorporating  their suggestions in the revised uploaded manuscript.

We hope that we have taken all critical and constructive comments into account in the revised  paper. We also hope that the current version meets your expectations.

Kind regards,

Jarosław Konior, Marek Sawicki and Mariusz Szóstak

Department of Building Engineering, Faculty of Civil Engineering, Wroclaw University of Science and Technology, 50-370 Wrocław, Poland

 

Here are answers to the reviewer’s comments – one by one:

REVIEWER 3

Dear authors,

I thank you for the change you have given to your initial submission. I still require some small changes:

 

Comment 1. line 202 : at least, give just one time, the detail of calculation of numbers within brackets. Add the detail of the calculation of (56.77% = 5 x 8 + 17 x ...+28 x...).

Answer 1. Technical wear of an apartment house as a whole has been calculated the following way:

Z = ZS₂ + ZS₃ + ZS₄ + ZS₇ + ZS₈ + ZS₉ + ZS₁₀ + ZS₁₃ + ZS₁₅ + ZS₂₀                

if:

ZS_i = S_i x Z_i                                                                

whereas:

S_i – element’s share in the building %]                                                                 

ZS_i – technical wear of the element as a part of the building’s technical wear [%]

Z_i – element’s technical wear (as a result of inspections) [%]

ZSi = 2.68 + 1.73 + 0.28 + 23.79 + 6.87 + 0.28 + 1.13 + 4.05 + 3.32 + 3.38 = 68,95%

The obtained and calculated data for determining the technical wear of an exemplary tenement house has been presented in the newly inserted table 2.

 

Comment 2. lines 243-4 : I had understood where the number of 15 objects came from, but I was not sure to understand the conclusion about the ineffectiveness of renovation. Here, for these "very affected" objects, do you consider that they so damaged that the only alternative is to demolish them ?

Answer 2. The conclusion of ineffective renovation has been drawn on a basis of the references: Nowogońska [28-29], Winniczek [43] and Hopfer [51-52] – see below.

Class of technical wear	State of the maintenance of building elements	Observed technical wear of building elements    [%]	Descriptive criteria of technical condition
V	Very poor	75, 80, 85, 90, 95, 100	In the building elements there are large damage and defects that can threaten or continue to use the object. To stop the process of deteriorating the building demolishing or at least exchange the most affected elements is indispensable.   In justified cases (economic, social), the end of the threat can be carried out by a major repair on a large scale.

Certainly, quoted indication of a very poor building condition heading for a “technical death” is limited to engineering aspects only, without consideration of economic, social and moral arguments. The significance of the statement is pretty low in the considered topic, without any further development in the presented research works.

 

Comment 3. Table 2 : I had also understood main meaning of this Table, but my concern was how this list is used for the following steps. There is no direct visible link between this Table and the modeling.

Answer 3. Table 2 shows the list  / classification of pinpointed defects relevant to the investigated elements and split into 4 groups of damages. These defects are caused by the accelerated technical wear, responsible for at least 70% of the entire deterioration of the buildings. This is supplementary information to normal technical wear justified by passage of time which was calculated as max 30 % and proofed in the presented research works. There is no direct link between table 2 and modeling which begins from item 2.4 and further.

 

Comment 4. Table 3 : I strongly suggest to complete this Table adding graphs for cases Z2 and Z20, as examples.

Answer 4. Agreed. The course of trends of determination coefficients R2 for 10 selected building elements has been introduced as the most interesting set of graphs and presented in the figure 2. What strikes is exceptional regularity of trends of graphs, no matter what model has been tested: linear, power, exponential, hyperbolic.

Author Response File: Author Response.pdf