Concrete Construction: How to Explore Environmental and Economic Sustainability in Cold Climates

Round 1

Reviewer 1 Report

The paper looks good and method is understandable. Method could potentially improve contractor's decision-making on concrete curing alternatives in a cold environment.

Comments:

Page 17, Line 539, Designed*
Page 18, Line 549, Using*
Page 22, Line 654. I guess Cost* and curing duration* should replace Curing duration and CO2 emissions in that sentence
Page 22, Line 670, ... are the pareto solutions or algorithm integrated into the current decision framework for contractors looking to achieve multiple objectives?

Author Response

Please see the attachment.

Reviewer 2 Report

General comments

 

The research topic is very interesting and the investigation procedure is described properly; the methodology adopted is presented in a very complete form.

 

The manuscript is worthwhile, but it is overly long for this journal. It should be about 80% of what it is now. For example, the detailed description of the prototype (section 4) and some repetitive discussions (section 6) could be removed of offset by some references.

 

The verb tenses adopted are not always coherent and should be corrected, especially in section 6. Furthermore, several English expressions could be improved as suggested below.

 

 

Editorial comments

 

- line 57, 247-248, 385, 394, 396, 400, 436, 456, 466, 482, 483, 500, 502, 510, 526, 528 , 533, 535, 551, 552, 555, 558, 563, 581, 598, 620, 621, 638, 642, 654, 677, 684, 700, 713, 714, 716

please remove “Error! Reference source not found”

 

- Figure 1

please give a different title to the y-axis on the left, give a title to the y-axis on the right, a white background for the graph can be employed

 

- Figure 4c

please enlarge

 

- Figure 8, 9, 10, 11, 12, 13

please use bigger fonts for all the text and numbers written, as the current font size is too small

 

 

Technical comments

 

- line 78-82

“Using higher-strength concrete or chemical admixtures”

the paper “Effects of pre-curing treatment and chemical accelerators on Portland cement mortars at low temperature (5 °C), Construction and Building Materials, Volume 240, 2020” can be also referred to since it provides a very thorough recent investigation at this regard

 

- section 5 and 6

is it possible to say something about another possible case study located in Northeast China (Heilongjiang province)? And possibly make some considerations if compared to the case study already accomplished in Nordmaling (Sweden/Scandinavia)?

 

 

Language comments

 

- subsection 2.1 needs a significative revision

 

- line 150

“its strength”

please use another expression for “its”

 

- line 151-153

please build a more fluent sentence

 

- line 159

“in two wayS”

 

- line 159

“The first ONE involves THE use”

 

- line 171-177

please rephrase as the current constructions are missing some grammatical features

 

- line 178-187

please rephrase as the current constructions are missing some grammatical features (i.e. several articles “the”)

 

- line 205-207

excessive repetitions of “curing”

 

- line 207-209

excessive repetitions of “casting”

 

- line 223

“optimization to optimize”

please avoid repetitions

 

- line 240

“after casting can the cast”

please avoid repetitions

 

- line 241-242

please avoid “concrete” repetitions

 

- line 243

“Thus, combining”

should be “Thus, the combination of”

 

 

- line 256-260

please avoid “curing” repetitions

 

- line 267-268

please avoid “model” repetitions

 

- line 277-287

please rephrase/double-check as the current constructions are missing some grammatical features

 

- line 292

“dependS”

 

- line 306

“Cost of mixing concrete refers to the cost”

please avoid “cost” repetition

 

- line 313

“refers” should be “refer”

 

- line 329

“exiting”

please use another verb

 

- line 336

“is to use warmer water”

please rephrase

 

- line 359

“THE values”

 

- line 367

“effects on THE considered”

 

- line 373

please remove “clearly”

 

- line 376

please avoid “proposed” repetitions

 

- line 391-393

please avoid “construction activities” repetitions

 

- line 401-402

please avoid “connect” repetitions

 

- line 417-418

please avoid “send” repetitions

 

- line 454

“comes”

should be “come”

 

- line 461-462

please avoid “calculation” repetitions

 

- line 486

“to test THE effects”

 

- line 535

“to test THE effects”

 

- line 537-539

please avoid “are designed” repetitions

 

- line 599

“to test THE effects”

 

- line 612-617

please shorten

 

- line 633-639

please avoid “curing” repetitions

 

- line 690

“associated WITH the”

 

- line 694

“are reportedly”

please correct

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 3 Report

This is a very interesting paper which considers the environmental and economic sustainability of curing measures. As most sustainability measures focuses on the material production this gives an opportunity for the contractor to address the construction stage. It also connects the material production with the on-site activities by addressing the consequence of choice of concrete.

General comments for improvement:

• In the introduction the problem with cold climate curing could be further emphasized with more details on costs impacts. How much does the curing measures cost compared to the total construction costs or material costs?
• The method needs to be clarified as it is difficult to fully analyze the results due to lack of information on the case study. It is also not clearly explained, including the LCA method used (for details see below).
• To understand the significance of the results it is important to consider the uncertainties in the input parameters. Will a change in a parameter lead to a completely different conclusion and what do the user need to think about in that case? A sensitivity analysis can help to understand the results and the limitations of the tool.
• In the conclusions the results are briefly described. It is mentioned that improvements can be made but it would also be interesting to understand how big this improvement is by putting it in a context. And what indications did the case study give us for example. The conclusions needs to be elaborated.
• The figure references in the text are missing. Please check that the document doesn't contain an error.

 

Detailed comments:

line 56: 5 degrees Celsius is 41 degrees Fahrenheit.

Figure 1: The Y axes should be Temperature and not Degree. 

Line 171: Is the time-strength relation also considered for supplementary cementitious materials such as fly ash and GGBS?

Line 191: Doesn't CMA also show time? What is the difference between the time aspect in CMA compared to the time in the construction performance parameter in this proposed method?

Line 216: The sentence needs further explanation. A suggestion is to use an example.

Line 251: The second module seem to exchange information with the first module. This can be clarified in the text.

Line 260: "The method is designed for short term decisions". This seems to be a limitation. What is the consequence of this when using the tool? It also says that it can be used for selecting standard measures for a standard floor. When is the tool not applicable? This can be mentioned in the conclusions also.

Figure 2. To make it easier for the reader the number of the modules can be written. For example, "Module 1". Since there is an exchange between module 1 and module 2 there should be two arrows, one for each direction. It seems that "modeling", "automation" and "decision support" are descriptions of the modules. In that case there should be no arrows as it indicates that they are input.

line 284: It is mentioned that the simulation stops and continues. What are the chosen intervals? 

Line 289 to 365: There needs to be an introduction to this section as this comes as a surprise to the reader. A sentence can be added in line 287.

Line 291: Which are the other activities and are these other construction activities relevant for the analysis? 

Line 318: An EPD is not a database and LCI is general for a life cycle inventory. Please rephrase and describe what the environmental database contains. There is also a lack of description of the LCA method used.

Figure 3. The environmental impact database is missing.

Figure 4 and 5. It's difficult to read the texts in the figures as they are too small. 

Line 448. In the case study a more detailed description of the slabs should be mentioned. The dimensions have an influence on the GWP. The reference which all the changes relate to should also be described.

Line 466: as previous comment. the LCA method should be described.

Table 1: A CEM II/A-V is used. Is the effect of the fly ash considered in CMA?

Table 2-4: is the information gathered from the site or from literature? It could be good to mention all the assumptions.

Line 509: How are the CO2 emissions for the indirect curing measures calculated?

Table 5: The calculated CO2 emissions of the concrete does include raw material transport to factory and energy use at factory. This should be motivated.

Line 556: In order to have a comparison a reference unit needs to be chosen. I guess that in this case it is 1 m2. This should be described in the method.

Figure 8: This is very difficult to read and to find the figures mentioned in the text. There are too many lines. I suggest improving the figures in general.

Line 637: what is included in this duration? How are the CO2 emissions calculated?

Table 8: It would be interesting to see what value the best curing measures have in other parameters. So all parameters are displayed for each combination.

 

 

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 3 Report

The paper has been improved and is of high quality.