Three-Dimensional Printing Using Recycled High-Density Polyethylene: Technological Challenges and Future Directions for Construction

This manuscript summarized the broad applications   of the AM in the construction field and described detailed information   regarding how the virtual model transforms to physical object. The authors also   briefly discussed challenges and future directions.

1)      It   appears that recycled HDPE in the concrete increases tensile strength.   Regarding the use of recycled HDPE, does it alter any innate physicochemical   properties when recycled?

2)        Are there any other materials that may offer   comparable properties?

3)        As the title of this article includes the   sustainability aspect, can the authors comment on sustainability and economic   advances using this materials more in details?

4)        Please revisit a list of references to unify its   listing style.

5)      Some   legends for the sectioned figures are needed to be modified (e.g. (a) and (b)   are needed to be separately explained).

1)      Yes, this is correct.  Recycled   HDPE can lead to changing both physical and mechanical properties as well as   chemical condition in the materials.

2)      Any kind of brittle materials can be used which   would be comparable.

Examples of brittle materials include cast iron, concrete, and some glass products.

3)        This topic came up with an idea about the   optimization. In this research both thermal and mechanical optimization in   lab scale sample numerically checked. The main advantages is to suggest a   technique where would be fast and efficient in construction and the input   materials economically would be justified. The suggested technique can   present future construction in the countryside and rural areas.

4)        All of the available references were revised.

5)        Further explanations were individually added.  

This paper dealt with a methodology for 3D   printing using recycled high-density polyethylene in construction processing   and architectural design. In addition, the authors showed their technological   challenges and sustainability. The proposed method is well explained and the   case study also illustrates the validity of the research.

The   authors would like to deeply express their appreciations.

The paper presents a research   on three-dimensional printing by using cement mix incorporated with recycled   waste product High Density Polyethylene (HDPE). The methodology applied is   interesting, the organization is good and the text is sufficiently clear.

The   authors would like to deeply express their appreciations.

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A   comprehensive (language) proof reading was conducted.