EGU2020-22163
https://doi.org/10.5194/egusphere-egu2020-22163
EGU General Assembly 2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

Evaluation of the seismic response at the Arquata Del Tronto hamlet through 3D numerical analyses

Ilaria Primofiore1, Julie Marie-Pierre Baron2, Giovanna Laurenzano2, Peter Klin2, Cristina Muraro3, and Giovanna Vessia1
Ilaria Primofiore et al.
  • 1University "G.d’Annunzio" of Chieti-Pescara, Department of Engineering and Geology (INGEO), Chieti (CH), Italy
  • 2Istituto Nazionale di Oceanografia e di Geofisica Sperimentale - OGS, Trieste, Italy
  • 3Istituto Superiore per la Protezione e la Ricerca Ambientale - ISPRA - Italian Geological Survey, Roma, Italy

(ilaria.primofiore@gmail.com; jbaron@inogs.it; glaurenzano@inogs.it; pklin@inogs.it; cristina.muraro@isprambiente.it; g.vessia@unich.it)

 

The 2016 Italian seismic sequence showed, once again, the relevant role of the differentiated seismic effects at short distance in varied geological environments. In the case study of Arquata del Tronto hamlet, several response analyses have been performed in order to reproduce the ground response through 2D finite element numerical codes (Primofiore, 2019; Pagliaroli et al., 2019). According to the Italian Guidelines for Seismic microzonation ICMS (2010), in the case of hills, the topographic effects of seismic amplification must be studied by numerical methods. In those cases, when the relieves are made up of soil deposits, 2D numerical analyses are used, indeed. Instead, when rocky hills are considered, the amplification effects due to the topography are considered by means of 1D simplified analyses or at most, 2D ground response analyses. The recent damages of old settlements located on the top of rocky hills, such as Arquata del Tronto hill, put in evidence the relevant role of three-dimensional movements of asymmetrical isolated rocky reliefs in generating heavy disruptions during the seismic shaking. In addition, on surface there are commonly fracturing layers of rocks, which played an important role in amplifying seismic waves according to their thicknesses. 3D numerical analyses at Arquata del Tronto hill have been carried out through the spectral element method implemented in SPECFEM3D code. Results suggested that an accurate simulation of the topographic effects of isolated asymmetrical rocky hills can be appreciated only through 3D numerical analyses, because they capture the out-of-plane bending moment (torsional effect) that asymmetry induces. The results showed that seismic behaviour of articulated morphology of the isolated relieves cannot be simulated by means of 2D seismic response analyses.

 

References

 

Pagliaroli, A., Pergalani, F., Ciancimino, A., et al. (2019). Site response analyses for complex geological and morphological conditions: relevant case-histories from 3rd level seismic microzonation in Central Italy.

Bulletin of Earthquake Engineering, 1-37.

 

Primofiore, I. (2019). Studio della risposta sismica in località Arquata del Tronto mediante modellazioni numeriche 3D. Master Degree thesis (in Italian), University “G. d’ Annunzio” of Chieti-Pescara.

 

Working group M. S. (2010). ICMS - Indirizzi e Criteri per la Microzonazione Sismica. In Conferenza delle Regioni e delle Provincie autonome. Dipartimento della protezione civile, Roma (Vol. 3).

 

How to cite: Primofiore, I., Baron, J. M.-P., Laurenzano, G., Klin, P., Muraro, C., and Vessia, G.: Evaluation of the seismic response at the Arquata Del Tronto hamlet through 3D numerical analyses, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22163, https://doi.org/10.5194/egusphere-egu2020-22163, 2020

Comments on the presentation

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Presentation version 3 – uploaded on 30 Apr 2020
I want to remove "photography not allowed" symbol.
  • CC1: Comment on EGU2020-22163, Hans-Balder Havenith, 01 May 2020

    Dear Iliaria,

    you show some nice simulation-based evidence of topography-related wave polarization effects. 

    Do you have field evidence for this ? Damage distribution? ... some later H/V measurements or even earthquake recordings?

    yours

    Hans

    • AC1: Reply to CC1, Ilaria Primofiore, 02 May 2020

      Dear Mr. Havenith, thank you for the question.
      Yes, we have H / V measurements that show directionality.
      A greater oscillation in the 90 ° azimuth can be seen in P193, while the peak in the perpendicular direction is observed in P195.Please do not pay attention to frequencies higher than 10 Hz, as they are certainly the result of anthropic disturbance.However, an investigations survey would be needed, to acquire more data, to be able to confirm my hypothesis.

      There is no evidence of differentiated damage if we consider the locations that respond differently to directionality. This is because there are no buildings on that relief, other than the castle and Old Town. While, regarding the differentiated damages between Borgo and Old Town, I recommend viewing the article by Graziani et al. (2019) "Investigation on damage progression during the 2016-2017 seismic sequence in Central Italy using the European Macroseismic Scale (EMS ‑ 98)".
      << The damage scenario [of Borgo] after the 1EQ is strikingly different from that of Arquata del Tronto. [...] The different damage behavior of these two villages, although very close to each other, can be partly due to both the building stock characteristics and the different location. >> (cit.)

      We have tried to explain these differences adding, to the valley and topographical effects, also a probable twisting effect.

      • CC2: Reply to AC1, Hans-Balder Havenith, 02 May 2020

        thanks,

        then, it would be nice to include this also in your presentation and compare simulation with H/V results

        Chat you on Mon

        Hans

Presentation version 2 – uploaded on 29 Apr 2020 , no comments
I had to add the CC BY 4.0 symbol to all the slides in the presentation
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