Experimental and Numerical Investigation into Full-Scale Model of New Type Assembled Integral Utility Tunnel
Round 1
Reviewer 1 Report
his paper summarizes the existing new prefabricated assembly type integrated Utility Tunnel, using prefabricated laminated plate type as well as tongue and groove joint connection method, completed a new prefabricated assembly type integrated utility tunnel design. Numerical simulations and field footage tests are used to obtain the stresses and cracks of the overall structure of the corridor under various working conditions and to verify the overall structural stress performance of the corridor after assembly.
But there are some capitalization, spelling, grammatical errors, and graphical quality errors in the article.
Be aware of the interpretation of terminology.
Unify the expressions of the terminology.
Need to pay attention to the quality of the graphs, like Figure 10, some information is missing and needs to be added.
But there are some capitalization, spelling, grammatical errors, and graphical quality errors in the article.
Be aware of the interpretation of terminology.
Unify the expressions of the terminology.
Need to pay attention to the quality of the graphs, like Figure 10, some information is missing and needs to be added.
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Based on a practical project, a new type of underground integrated pipe corridor structure is proposed in this paper. Then the structural properties of the new underground integrated pipe corridor such as crack distribution, deformation, reinforcement and concrete strain are studied by full scale test and finite element numerical simulation, and the feasibility of the new underground integrated pipe corridor is verified. The research content has certain practical value, but it has the following shortcomings:
（1）in section 2.2: “The structural reinforcement diagram of the prefabricated assembled integral underground utility tunnel is composed of 9 prefabricated components, calculated based on the concrete density of 2500kg/m3”
There are only 8 precast parts and it is recommended to indicate the design strength level of the concrete used for precast parts as this is relevant for later finite element analysis.
（2）in section 2.3: “The displacement diagram obtained through finite element analysis is shown in Figure 6(a), and the stress diagram is shown in Figure 6(b).”
The concrete grade of precast parts needs to be supplemented. The contact surface between precast parts and postcast concrete is a weak surface. How to consider the superimposed surface of old and new concrete in finite element analysis?
（3）in section 3.1: “The full-scale model was 7.4 meters long, 4.0 meters wide, and 4.0 meters high.” is suggested to revised as: “The full-scale model was 7.4 meters wide, 4.0 meters high, and 4.0 meters long.”
（4）in section 3.2: It is suggested to supplement the graded loading system, that is, the load of each stage across the roof and side wall.
（5）in section 4.1: It is suggested to supplement the fracture distribution diagram of the whole pipe gallery under the final load.
（6）in section 4.2: There were errors in Figure 10, such as the legend does not correspond to each other, the location of measuring points is not marked, and the deformation proportion is inconsistent.
（7）in section 4.3: It is suggested to add reinforcement and concrete strain measuring point layout in FIG. 11 and FIG. 12.
（8）“From the strain distribution diagram of the mid-span section of the composite board, it can be seen that the neutral axis position of the section is not in the middle position but above the composite surface.”
Composite slab concrete section strain profile missing, please add.
（9）in section 4.4: “Compare the full-scale model test results with the simulated experimental values and finite element simulation results of the deflection values of the top plate.”
simulated experimental values is suggested as theoretical calculated values.
The English is good in this manuscript.
Author Response
Due to the reply content is more, and contains pictures, Please see the attachment.
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Reviewer 3 Report
In the reviewed study, the construction methods of prefabricated utility tunnels are comprehensively discussed. Comparisons were made with experimental and numerical data. The general deficiencies in the study can be summarized as follows;
1) In the summary part, important findings should be given briefly.
2) The introduction part of the study contains very general information. Purpose, important, scope, objectives of the study, etc. not given. It should be noted that it differs from other studies in the literature.
3) The advantages of the proposed method should be mentioned in the last paragraph of the introduction, this part should be included in the discussion or conclusion section and discussed in detail there.
4) Figure 2 is not understood. The picture should be enlarged further.
5) Concrete sidewalls are very critical at the junction of PC3 and PC1. Here, sectional analyzes and connection area analyzes should be done in detail.
6) More detailed information about ABAQUS models should be given. In this regard, the presentations of some sources in the literature can be used.
YO Özkılıç, C Aksoylu, MH Arslan “Numerical evaluation of effects of shear span, stirrup spacing and angle of stirrup on reinforced concrete beam behavior” - Structural Engineering and Mechanics, An Int'l Journal, 2021
https://doi.org/10.12989/scs.2022.43.6.735
https://doi.org/10.1016/j.istruc.2022.05.061
7) Typical soft soil geological conditions are a very important parameter, especially the base pressure. This part should be explained in more detail.
Author Response
Due to the reply content is more, and contains pictures, Please see the attachment.
Author Response File: Author Response.docx
Round 2
Reviewer 2 Report
Thanks to the authors'. All comments have been addressed, and the manuscript is currently acceptable in its present form.
Author Response
Once again, thank you very much for your comments and suggestions.
Reviewer 3 Report
The authors have made the suggested corrections. It can be accepted if deemed appropriate by the editorial board of the journal.
Author Response
Once again, thank you very much for your comments and suggestions.
