Cause Analysis of Pier Inclination of An Expressway Interchange Bridge: Case Study

Round 1

Reviewer 1 Report

Numerical analysis and on-site measurements were being carried out, and detailed verification was worthy of evaluation. However, there are the following problems.

L25: Although it is written as "The pier inclination disease in bridge has been increasing", this is a special situation in China and is not common in the world. The description method is inappropriate. With proper design and construction, such deformation will not occur.

Chapter 1:

Such construction defects can be prevented by designing and constructing in anticipation of possible risks in advance.

Various simulations may be conducted, but first, design and construction techniques that do not cause such construction defects should be considered.

Numerical simulations should be conducted assuming possible risks in the pre-construction study. It is meaningless after the deformation has occurred.

Figure 1;

It is inappropriate to paste a copy of the drawing. You should replace it with an appropriate diagram of what you want your readers to understand. I didn't understand where the target bridge is. Information such as pier numbers and curve radii cannot be read at all.

Figure 2, 20; The letters should be large. 

Figure 3 ;

You should explain what kind of transformation is happening. The figure should be enlarged and balloons should be included so that the reader can understand the transformation.

4.3. 

The construction plan is simply inadequate. This analysis is not an engineeringly useful finding.

5.1.

Following the initial design change of adopting a steel box girder, there were big problems in the design system that did not review the design of the pier.

6.

I cannot understand which value in the figure is the measured value and which value is the analysis value.

6.2.

For example, "the inclination of Pier P33 top is 2.6/7.6cm" I didn't understand what the numbers 2.6 and 7.6 mean.

7.

It is a deformation that could be prevented if appropriate studies were conducted before the design and construction were carried out. It's just an improper design and construction flaw. It is unclear what the new findings are for the paper as a whole. "The lesson learned from this case study" is quite general.

Author Response

Dear reviewer:

     Please see the attachment for response to the reviewer’s comments 

Author Response File: Author Response.docx

Reviewer 2 Report

Please find attached a PDF file with my comments and suggestions for authors.

Comments for author File: Comments.pdf

Author Response

Dear reviewer:

     Please see the attachment for response to the reviewer’s comments 

Author Response File: Author Response.docx

Reviewer 3 Report

This manuscript invesitagted the reasons that induce pier inclination, escessive support slip, and expansion joint damage of pier-support-girder regions. It concludes that suitable support eccentricity should be determiend to reduce eccentric compression caused by superstructure. This article is well constructed and well wrriten. It is recommended accepted.

Author Response

Dear reviewer:

     Please see the attachment for response to the reviewer’s comments 

Author Response File: Author Response.docx

Reviewer 4 Report

Dear Authors,

The authors presented an interesting case of damage to the transfer bridge structure using the available measurement techniques and numerical simulations. The case study is quite important from an engineering point of view. A fairly broad analysis of investigating the causes of the disease phenomenon in a particular building was used. The work is generally good, although there are some shortcomings, mostly editing.

In my opinion, the literature review is too poor (14 ref.) and this should be completed. 

In the text, numbers and units should be separated, incorrect entry, for example: line 67 or 192, 216.

Most of the drawings should be enlarged (Figs. 2, 3, 4, 6, 7, 8, 9, 11, 13, 17, 18, 20, 21) or their quality improved (Fig. 5), as they are difficult to read.

The analyzes performed seem to be correct. Therefore, I propose an article for publication after completing the literature and making some corrections in the text. In order to supplement the literature, I suggest the authors search the sciencedirect database.

Thank you

Author Response

Dear reviewer:

     Please see the attachment for response to the reviewer’s comments 

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

I pay tribute to the author's sincere response. Thank you.

Let me comment on just one.

References 1 and 2 are old. If constructed with the latest technology, it is possible to prevent the piers inclination. Please describe that the inclination of the pier occurs in a special case such as when there were problems in the construction process. Even if it is "Interchange construction often beneath some existing bridges and roads."

Author Response

Dear reviewer:

The authors thank for the reviewer’s comment. In revised manuscript, reference 1 and 2 have been replaced with similar literatures that published recent years.

In bridge construction, just considering technical issue, if constructed with latest technology, the construction quality can be guaranteed. However, authors’ team has been investigated many practical engineering cases, and find that there are some other issues leading to pier inclination. Two special cases are described as following:

Special case 1: There are roads in operation adjusted to construction site. During bridge construction, Loads such as heavy trucks that are passing or parking on the nearby road cause foundation settlement, which is a cumulative process, the soft soil foundation produces large lateral deformation while settling, then the adjacent bridge piers incline under the lateral deformation of foundation soil, especially when pier construction is completed while the superstructure is not.

Special case 2: The pier is located between river and riverbank. As we know, sometimes the river channel needs desilting. Just like the case in manuscript, there is a river beside Pier P30, however, the river maintenance unit carried out dredging and excavation in the river without coordination with construction enterprise, as a result, the silt around Pier P30 was excavated in a depth of 2 m at the river side and dumped in the other side. which resulted in asymmetric filling soil load at the bottom of Pier P30, so the pier inclined under asymmetric filling soil load at the bottom.