Numerical Simulation and Field Test of the Interaction between Existing Station and Enclosure in Open Excavation and Adding Stories Construction

Round 1

Reviewer 1 Report

The construction method of zero-distance open excavation foundation pit above the existing station structure is rare. It is of great significance to study the cross influence of the new structure and the existing structure in the process of increasing the upper layer of the existing station. Through numerical simulation and field measurement, this paper explores the deformation law of existing station and retaining structure, and puts forward specific safety control measures. The research results have certain academic value. However, there are some minor points that should be addressed. The suggestions are as follows:

(1) The stratigraphic description in Section 2.2 ‘Geological and Hydrological Conditions of Construction’ is inconsistent with the stratigraphic notation in Figure 2 and needs to be modified.

(2) Explain the model size value in Section 3.1 ‘Calculation Model’, and what reference values 3.3H and 2H are based on.

(3)  The content of Table 1 is repeated and needs to be modified. In addition, the value of sandstone cohesion in Table 1 is explained. Why is the value of cohesion 100Kpa?

(4) In Section 3.3‘Deformation of the Retaining Structure’, Z3 pile is located between two steel braces. Please further explain the difference between Z2 pile and Z3 pile, and explain why the piles here are selected for comparison?

(5) In section 4.1.3‘Influence of excavation Earth Berm’, whether the scope of the reserved back pressure soil is consistent with 4.2.3, it is suggested that the scope of the back pressure soil in the numerical calculation should be supplemented here.

(6) It is recommended to show the location of the existing station B-B ' line in Figure 5 (b) and Figure 17 to make the picture more intuitive.

(7) The monitoring point in Figure 18 (a) does not correspond to the horizontal displacement in Figure 19. It is recommended to check the monitoring point number and modify it accordingly.

Author Response

Dear reviewers:

Thank you for giving us the opportunity to submit a revised draft of the manuscript. We have read your comments carefully and revised the details of the manuscript. Attached please find the revised version, which we would like to submit for your kind consideration.

Author Response File: Author Response.pdf

Reviewer 2 Report

This paper deals with the analysis of the Interaction between Existing Station and Enclosure in Open Excavation and Adding Stories Construction. The work takes a fundamental approach for investigation and considers both numerical simulations and relevant field tests.

The topic of the paper is important and requires investigation. The writing is good with relevant review of the current state of knowledge. Although the literature review could be improved (e.g., add a couple of more references related to previous similar work) and more critical discussion be added, it is in general acceptable. 

The figures and illustrations are relevant and appropriate. The data presented are useful.

This is good work. Thank you for your contributions.

I suggest publication as is.

Author Response

Dear reviewers:

Thank you for giving us the opportunity to submit a revised draft of the manuscript. We have read your comments carefully and revised the details of the manuscript. Attached please find the revised version, which we would like to submit for your kind consideration.

Author Response File: Author Response.pdf