Soil–Structure Interaction Assessment of the 23 November 1980 Irpinia-Basilicata Earthquake

Round 1

Reviewer 1 Report

This manuscript aims presenting a numerical study on the soil-structure interaction based on the Irpinia-Basilicata earthquake in Italy. A numerical work was developed to assess the soil-structure interaction in the structures response. The study is important and addresses an important issue regarding the seismic behaviour of structures. However further explanations are needed. Also, the reviewer found that some English grammar errors. The authors are advised to check the manuscript again carefully in order to avoid English grammar errors.

My assessment is that this work are interesting. However, some revisions and clarifications are required before the manuscript is suitable for publication, as outlined in the following points.

Abstract:

• Please include major findings.

Background

• Which type of structures were more affected?
• Please provide examples of the importance of the soil acceleration amplification in recent earthquakes such as Nepal. Please consider the following references:

2017. Varum, A. Furtado, H. Rodrigues, J. Dias-Oliveira, N. Vila-Pouca, and A. Arêde, "Seismic performance of the infill masonry walls and ambient vibration tests after the Ghorka 2015, Nepal earthquake," Bulletin of Earthquake Engineering, vol. 15, no. 3, pp. 1185-1212, 2017/03/01 2017.

2016. Gautam, H. Rodrigues, K. K. Bhetwal, P. Neupane, and Y. Sanada, "Common structural and construction deficiencies of Nepalese buildings," Innovative Infrastructure Solutions, journal article vol. 1, no. 1, p. 1, March 29 2016.

63. Varum, R. Dumaru, A. Furtado, A. R. Barbosa, D. Gautam, and H. Rodrigues, "Chapter 3 - Seismic Performance of Buildings in Nepal After the Gorkha Earthquake," in Impacts and Insights of the Gorkha Earthquake, D. Gautam and H. Rodrigues, Eds.: Elsevier, 2018, pp. 47-63.

• The state-of-art review of numerical methodologies used to assess the role of the soil amplification is poor. Please improve

Case Study

• The authors must justify the reason behind the type of structure selected. It is well known that the structure response depends highly of their own natural frequency. The reader needs to understand the type of structure selected and the relationship with those existing that were effected by the earthquake.
• Was it selected the accelerogram of the three directions? Please provide information regarding that. The authors should provide the natural frequencies of the building structure with and without the masonry walls;
• Please highlight the effect of including the masonry walls in the building natural frequencies. Please consider the following reference to justify:

2018. Furtado, H. Rodrigues, A. Arêde, H. Varum, M. Grubišić, and T. K. Šipoš, "Prediction of the earthquake response of a three-storey infilled RC structure," Engineering Structures, vol. 171, pp. 214-235, 2018/09/15/ 2018.

Case Study

• What is the consequence of varying the position of the water?
• It would be interesting, since the authors considered only one accelerogram, to perform the analysis considering the three types of soils (dry and water)

Discussion

• Please merge this section with the section “results”.

Conclusions

• Please improve the conclusions by including the numbers of the soil amplification result

Author Response

Please see the attached file

Author Response File: Author Response.docx

Reviewer 2 Report

Typo corrections. Replace bold text with text in italics, or as specified.

25 Calitri, San Giorgio La Molara, and Grassano) [1-4]. It consisted of several rupture episodes occurred

Episodes which occurred

27 A wide area (about 3500 km2) recorded serious damages, many casualities and fifteen localities were

damage

29 Pescopagano, and Balvano. It is estimated that on a total of approximately 1.85 milion buildings

of

34 on the buildings. Eight damage levels were defined by considering the action to be undertaken, such

to

37 the earthquake at urban scale. An important study regarding the effects of spectral accelerations was

at the urban

39 particular attention to Naples area. In addition, [8] simulated the recorded strong-motion data by

To the Naples

50 [9-11]. In this regard, when superficial deposit lies over the bedrock, amplifications of surface seismic

deposits overlie

55 response of the superficial layers is strongly influenced by the uncertainty associated to the definition

56 of soil properties and model parameters that are fundamental to assess well known mechanism of

Assess the well

62 a first step where free-field (FF) analyses are computed on several layers of soil and performing a SSI

and secondly, performing

69 on Irpinia earthquake, strength parameters for superficial layers were not available. Therefore, it was

on the Irpinia

70 necessary a preliminary study aimed to select representative values based on available information,

necessary for a

delete “aimed”

74 that the ground motion amplitude decreases at the foundation level with respect to the free-field may

which decreases….

79 were found in literature. Then a complete 3D numerical model with the system (soil + foundation +

in the literature

replace Then with Secondly

81 material with a 3D mesh (Figure 1). Penalty method is adopted for the boundary conditions (tolerance

The penalty

85 (described by the 3rd DOF) is constrained in correspondence with all the boundaries (at the base and

according to

89 verify proper simulation of FF conditions in correspondence with lateral boundaries, accelerations at

that conform

215 the range of periods between 0 to 1 s. It is worth to consider the role of soil deformability in the

considering

218 structure can be founded (maximum amplification: 1.66) since the TF peak occurs in correspondence

conjunction

220 section 3.2). It is worth to note that amplifications were less significant in correspondence with the

221 other soil models. Dry conditions were shown to be noticeable for those periods that are far from the

This sentence is not clear in meaning. Do you mean that the amplifications were less significant compared to the other soil models, or in relation to the other soil models...

223 those in correspondence of saturated conditions. S1 seems to behave different from the other cases,

that relate to

228 [39, 40 and 41], there has been an increasing attention to new engineering demand parameter (EDP)

in the

236 at the base of the structure. It is possible to see that the diagram presents the typical hysterical

hysteresis

238 that the rocking component of the foundation did not affect relevantly the performance of the

relevantly affect

244 of the longitudinal accelerations and thus the seismic performance of the structure. It is worth to see

250 addition, it is worth to notice the significant peak in correspondence with 0.6 s, where all the

noting

256 cm, meaning that a consistent translation occurred in correspondence with the foundation level. In

accordance

258 displacements along the height of the buildings and in correspondence of the various floors. The

relation to

259 maximum top displacement in correspondence with the top of the structure was 1.885 cm, that can

relation to

261 Figure 15 represents shear forces versus longitudinal displacements in correspondence with the

accordance

263 and to determinate the potential mechanism of collapse. It is worth to notice that the values were

noting

280 The results demonstrated firstly that the numerical model performed the system (ground281

Delete firstly.

Replace performed with simulated

281 foundation-structure) properly, allowing to assess the importance of the soil deformability in the

allowing us to

285 In this regard, the values of the shear forces in correspondence with the masonry elements showed

relation to

286 that the potential damage can be the shear failure, as expected and as demonstrated in the typical

Delete “the”

289 The paper investigates the effects of soil deformability on a typical structural configuration by

investigated

290 analysing a 3D soil-structure model built up with OpenSeesPL and the results are the consequences

OpenSeesPL; the

292 proposing a model that performs detailed 3D models of both the soil and the structure and assessing

Replace models with “simulations”

structure; allowing an assessment of

294 Overall, the paper demonstrates that a rigid, low-rise building may experience big amplifications

configuration

295 effects due to soil deformability that needs to be accounted for this kind of structural configurations.

for in this….configuration

296 Even if the findings are limited to the considered conditions, they may potentially be useful to

specified conditions presented here,

297 propose formulations that include SSI effects inside code provisions. In this regard, future parametric

within

298 numerical simulations of the response of other structural typologies will be performed.

are recommended.

326 Earthquake in the Eastern Area of Naples Earthquake Spectra (16)n.3, 2000

Insert space

334 assessment of RC buildings. Bull Earthq Eng 2014;12(4): 1755 – 76.

Insert space

357 20. Amorosi, A., Castellaro, S., Mulargia, F. (2008), “Single-Station Passive Seismic Stratigraphy : an

Remove space

365 vol. Insights and Innovations in Structural Engineering, Mechanics and Computation, pp. 364-369, ISBN:978-1-

Insert space

369 25. Rodriguez-Marek A, Kruiver PP, Meijers P, Bommer JJ, Dost B, van Elk J, Doornhof D. A regional site370

response model for the Groningen gas field. Bull Seismol Soc Am 2017;107(5):2067–77.

response

Insert space

383 32. Zienkiewicz, O. C., Chan, A. H. C., Pastor, M., Paul, D. K., and Shiomi, T.(1990). “Static and dynamic

Insert space

399 38. CIRCOLARE 2 febbraio 2009 , n. 617 Istruzioni per l'applicazione delle «Nuove norme tecniche per le

Remove space

421 Innovations in Structural Engineering, Mechanics and Computation, pp. 364-369, ISBN:978-1-138-02927-9.

Insert space

Abstract: add in a sentence briefly summarising the results. Currently you state what will be discussed and how the study can be applied and the numerical solutions that are performed. Say what the results of the numerical simulations were? (ie that it modelled the ground-foundation-structure correctly)

Author Response

Please consider the developed version of the manuscript, uploaded here

Many thanks

Regards

Typo corrections. Replace bold text with text in italics, or as specified.

Many thanks, please see the modifications in the developed version.

25 Calitri, San Giorgio La Molara, and Grassano) [1-4]. It consisted of several rupture episodes occurred

Episodes which occurred

27 A wide area (about 3500 km2) recorded serious damages, many casualities and fifteen localities were

damage

29 Pescopagano, and Balvano. It is estimated that on a total of approximately 1.85 milion buildings

of

34 on the buildings. Eight damage levels were defined by considering the action to be undertaken, such

to

37 the earthquake at urban scale. An important study regarding the effects of spectral accelerations was

at the urban

39 particular attention to Naples area. In addition, [8] simulated the recorded strong-motion data by

To the Naples

50 [9-11]. In this regard, when superficial deposit lies over the bedrock, amplifications of surface seismic

deposits overlie

55 response of the superficial layers is strongly influenced by the uncertainty associated to the definition

 56 of soil properties and model parameters that are fundamental to assess well known mechanism of

Assess the well

62 a first step where free-field (FF) analyses are computed on several layers of soil and performing a SSI

and secondly, performing

69 on Irpinia earthquake, strength parameters for superficial layers were not available. Therefore, it was

on the Irpinia

70 necessary a preliminary study aimed to select representative values based on available information,

necessary for a

delete “aimed”

74 that the ground motion amplitude decreases at the foundation level with respect to the free-field may

which decreases….

79 were found in literature. Then a complete 3D numerical model with the system (soil + foundation +

in the literature

replace Then with Secondly

81 material with a 3D mesh (Figure 1). Penalty method is adopted for the boundary conditions (tolerance

The penalty

85 (described by the 3rd DOF) is constrained in correspondence with all the boundaries (at the base and

according to

89 verify proper simulation of FF conditions in correspondence with lateral boundaries, accelerations at

that conform

215 the range of periods between 0 to 1 s. It is worth to consider the role of soil deformability in the

considering

218 structure can be founded (maximum amplification: 1.66) since the TF peak occurs in correspondence

conjunction

220 section 3.2). It is worth to note that amplifications were less significant in correspondence with the

221 other soil models. Dry conditions were shown to be noticeable for those periods that are far from the

This sentence is not clear in meaning. Do you mean that the amplifications were less significant compared to the other soil models, or in relation to the other soil models...

This sentence has been completely canceled because not necessary

223 those in correspondence of saturated conditions. S1 seems to behave different from the other cases,

that relate to

228 [39, 40 and 41], there has been an increasing attention to new engineering demand parameter (EDP)

in the

236 at the base of the structure. It is possible to see that the diagram presents the typical hysterical

hysteresis

238 that the rocking component of the foundation did not affect relevantly the performance of the

relevantly affect

244 of the longitudinal accelerations and thus the seismic performance of the structure. It is worth to see

250 addition, it is worth to notice the significant peak in correspondence with 0.6 s, where all the

noting

256 cm, meaning that a consistent translation occurred in correspondence with the foundation level. In

accordance

258 displacements along the height of the buildings and in correspondence of the various floors. The

relation to

259 maximum top displacement in correspondence with the top of the structure was 1.885 cm, that can

relation to

261 Figure 15 represents shear forces versus longitudinal displacements in correspondencewith the

accordance

263 and to determinate the potential mechanism of collapse. It is worth to notice that the values were

noting

280 The results demonstrated firstly that the numerical model performed the system (ground281

Delete firstly.

Replace performed with simulated

281 foundation-structure) properly, allowing to assess the importance of the soil deformability in the

allowing us to

285 In this regard, the values of the shear forces in correspondence with the masonry elements showed

relation to

286 that the potential damage can be the shear failure, as expected and as demonstrated in the typical

Delete “the”

289 The paper investigates the effects of soil deformability on a typical structural configuration by

investigated

290 analysing a 3D soil-structure model built up with OpenSeesPL and the results are the consequences

OpenSeesPL; the

292 proposing a model that performs detailed 3D models of both the soil and the structure and assessing

Replace models with “simulations”

structure; allowing an assessment of

294 Overall, the paper demonstrates that a rigid, low-rise building may experience big amplifications

configuration

295 effects due to soil deformability that needs to be accounted for this kind of structural configurations.

for in this….configuration

296 Even if the findings are limited to the considered conditions, they may potentially be useful to

specified conditions presented here,

297 propose formulations that include SSI effects inside code provisions. In this regard, future parametric

within

298 numerical simulations of the response of other structural typologies will be performed.

are recommended.

326 Earthquake in the Eastern Area of Naples Earthquake Spectra (16)n.3, 2000

Insert space

334 assessment of RC buildings. Bull Earthq Eng 2014;12(4): 1755 – 76.

Insert space

357 20. Amorosi, A., Castellaro, S., Mulargia, F. (2008), “Single-Station Passive Seismic Stratigraphy : an

Remove space

365 vol. Insights and Innovations in Structural Engineering, Mechanics and Computation, pp. 364-369, ISBN:978-1-

Insert space

369 25. Rodriguez-Marek A, Kruiver PP, Meijers P, Bommer JJ, Dost B, van Elk J, Doornhof D. A regional site370

response model for the Groningen gas field. Bull Seismol Soc Am 2017;107(5):2067–77.

response

Insert space

383 32. Zienkiewicz, O. C., Chan, A. H. C., Pastor, M., Paul, D. K., and Shiomi, T.(1990). “Static and dynamic

Insert space

399 38. CIRCOLARE 2 febbraio 2009 , n. 617 Istruzioni per l'applicazione delle «Nuove norme tecniche per le

Remove space

421 Innovations in Structural Engineering, Mechanics and Computation, pp. 364-369, ISBN:978-1-138-02927-9.

Insert space

Abstract: add in a sentence briefly summarising the results. Currently you state what will be discussed and how the study can be applied and the numerical solutions that are performed. Say what the results of the numerical simulations were? (ie that it modelled the ground-foundation-structure correctly)

Many thanks for your observation, please see the developed abstract.

Author Response File: Author Response.docx