Accounting for the Spatial Variability of Seismic Motion in the Pushover Analysis of Regular and Irregular RC Buildings in the New Italian Building Code

Round 1

Reviewer 1 Report

The article ”Accounting for the spatial variability of seismic  motion in the pushover analysis of regular and irregular RC buildings in the new Italian Building Code” is interesting and it is in the area of research of the journal. The objective of this study is to investigate the effects of the new trends followed by guidelines regarding push over analysis according with 2018 version of the Italian Building Code NTC18. The results, in terms of global and local performances, are processed and analysed underlining the new and traditional approaches.    

After carefully reading the manuscript, I can confirm that the analysis presented here is interesting and actual. The organization of the paper is good, the author/authors put some effort to present everything in a clear manner, but there are some sentences that must be improved in order to clarify the meaning, thus making the comments more English language related. The observations and suggestions are given below:

1. Please provide a nomenclature for the used terms. There are a lot of variables which are not explained. Please ensure that all the parameters are having the proper nomenclature;
2. Line 26. Please change “practitioners” with “designers”
3. Line 30. Please rephrase “…such as the hierarchy strength…”
4. Line 31. Please rephrase “…the seismic performance is more articulated to be defined…”
5. Line 33. Please change “structural features” with structural properties
6. Line 34. Please change the expression “numerical strategy”
7. Line 42. Please commence the phrase with “In order to….”
8. Line 45. Please change “horizontal actions”
9. Line 49. Please change “regulatory framework” into design codes provisions (I think is more suitable)
10. Line 54. “Comercial codes?” there is no commercial code…. Maybe Design codes…..
11. Line 60. Please change “before leaving the room for good…..”

Also, if possible, please describe an additional solution for combining the effects of seismic motion. The EN1998 provisions are presenting additional solutions.

Author Response

Dear Reviewer, 

see the attached file for all the responses.

Kind Regards 

Giuseppina Uva

Author Response File: Author Response.pdf

Reviewer 2 Report

The present paper aims to investigate the effects of the new trends followed by the recent 2018 release of the Italian Building Code about pushover analysis. This is undoubtedly a subject of current relevance in building engineering (in particular earthquake engineering) and, as such, it falls within the scope of the Journal.

Given that the validation of relatively new procedures, such as pushover analyses, requires a large number of evaluation studies, every contribution to this domain could be of potential interest. Thus, despite this work does not present a high level of originality/novelty and does not resolve a given issue that is still open in the literature, it shows some interesting results and offers to the readers important recommendations for future work.

Authors should review the numbering used throughout the article. From reference [5] (which should be [6] according to the reference list) all other references are not well identified in the article.

In the paper should be clear, from the beginning, that the study focuses on the analysis of RC framed buildings and include regular and irregular in- plan (and not in-height) structures.

A list of more detailed and minor comments is provided and that can be considered by the authors aiming at help in improving the quality of the paper. ​

Section 1. Introduction

Lines 37-38: The authors refer “dynamic form (combining the effects due to all vibration modes)” but not always all modes are combined but instead only the most relevant ones.

Section 2. Pushover analysis: a brief overview of conventional and non-conventional methods

In this section, although it is provided adequate background and it includes relevant references a recommendation is proposed. When it is referred the non-conventional methodologies and in particular the adaptive pushover, the authors should mention the Extended Adaptive Capacity Spectrum Method (Extended ACSM) (https://doi.org/10.1193/022112EQS048M) proposed for the seismic analysis of Plan-Asymmetric Buildings. In the Extended ACSM, the ACSM is complemented with the accurate features of other commonly used nonlinear static methods.

Section 3. New provisions about conventional pushover analyses in the Italian Building Code

Line 173 – In the list of references for the reference [41] (which should be the number the authors would like to refer), it is presented the Eurocode 2 and not the Eurocode 8.

Equation (5) and lines 190-191: Here the authors should mention the for typical building structures the vertical component of the earthquake is not considered.

Figure 1c)- to be in agreement what it is written it is suggested to have S_x and 0.3S_y.

Section 4. New provisions about conventional pushover analyses in the Italian Building Code

Line 241: this sentence is not clear. It is suggested to mention “different participating masses of the fundamental mode in the Y direction ....”

Figure 2: Units are missing.

Line 278: In figure 2 the reinforcement of the structural elements is not given. These values should be included in the manuscript.

In this section some information is still missing: For the characterization of the constitutive laws of the plastic hinges, the authors considered confined and unconfined concrete? How these laws were defined?

Figure 4- To help the reader in the legend should be added to the meaning of T, U F, S. The same applies for figure 6.

Line 347: After this sentence, although the pushover curves obtained for only load profiles are only shown for the reference, symmetric, building, some comments should be included in other buildings. It should be added some comments related to the comparison comparing the curves corresponded to lateral loads in both directions with the ones where only one lateral load was adopted.

Section 5. Discussion of results

Lines 353-354: Why “this innovative procedure based in the CSM and described in reference [46] (and not [45]?) is only referred in this section and was not presented and described in section2?

Table 3: The D/C ratios presented in this table for all models and capacity curves, are the maximum value from all of the structural elements of each model?

Lines 374-377: This paragraph is repeated.

Author Response

Dear Reviewer, 

see the attached file for all the responses.

Kind Regards 

Giuseppina Uva

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

I approve the manuscript in the latest revised form.