Rate/state Coulomb stress transfer model for the CSEP Japan seismicity forecast

The purpose of the research was to study the aerodynamic features of the flow around the simplest structural elements of an aircraft, such as sharp and blunt-nose cones. For calculations we applied the perfect gas model. To describe flows with large adverse pressure gradients, we used the Menter's shear stress transfer model. We analyzed changes in the aerodynamic characteristics of the cones in a wide range of angles of attack α and flow Mach M∞ numbers. Furthermore, we investigated the parameters of the base region of the sharp cone at transonic and supersonic speeds, and compared the simulation results with the data of a physical experiment both in wind tunnels and on a ballistic installation. The comparison showed good agreement with the experimental data. Numerical simulation data can be applied to form the external appearance of aircraft for various purposes, to study the influence of the temperature factor on the flow around bodies, and to create semi-empirical models for calculating the parameters of the base region of conical bodies.

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Coulomb stress transfer and fault interaction over millennia on non-planar active normal faults: the Mw 6.5–5.0 seismic sequence of 2016–2017, central Italy

Geophysical Journal International ◽

10.1093/gji/ggx213 ◽

2017 ◽

Vol 210 (2) ◽

pp. 1206-1218 ◽

Cited By ~ 32

Author(s):

Zoe K. Mildon ◽

Gerald P. Roberts ◽

Joanna P. Faure Walker ◽

Francesco Iezzi

Keyword(s):

Main Shock ◽

Central Italy ◽

Stress Transfer ◽

Historical Record ◽

Normal Faults ◽

Coulomb Stress ◽

Seismic Sequence ◽

Fault Interaction ◽

Slip Rates ◽

Stress Changes

Abstract In order to investigate the importance of including strike-variable geometry and the knowledge of historical and palaeoseismic earthquakes when modelling static Coulomb stress transfer and rupture propagation, we have examined the August–October 2016 A.D. and January 2017 A.D. central Apennines seismic sequence (Mw 6.0, 5.9, 6.5 in 2016 A.D. (INGV) and Mw 5.1, 5.5, 5.4, 5.0 in 2017 A.D. (INGV)). We model both the coseismic loading (from historical and palaeoseismic earthquakes) and interseismic loading (derived from Holocene fault slip-rates) using strike-variable fault geometries constrained by fieldwork. The inclusion of the elapsed times from available historical and palaeoseismological earthquakes and on faults enables us to calculate the stress on the faults prior to the beginning of the seismic sequence. We take account the 1316–4155 yr elapsed time on the Mt. Vettore fault (that ruptured during the 2016 A.D. seismic sequence) implied by palaeoseismology, and the 377 and 313 yr elapsed times on the neighbouring Laga and Norcia faults respectively, indicated by the historical record. The stress changes through time are summed to show the state of stress on the Mt. Vettore, Laga and surrounding faults prior to and during the 2016–2017 A.D. sequence. We show that the build up of stress prior to 2016 A.D. on strike-variable fault geometries generated stress heterogeneities that correlate with the limits of the main-shock ruptures. Hence, we suggest that stress barriers appear to have control on the propagation and therefore the magnitudes of the main-shock ruptures.

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Stress Transfer Model for Single Fibre and Platelet Composites

Journal of Composite Materials ◽

10.1177/002199839903301604 ◽

1999 ◽

Vol 33 (16) ◽

pp. 1525-1543 ◽

Cited By ~ 21

Author(s):

D. A. Mendels ◽

Y. Leterrier ◽

J. A. E. Manson

Keyword(s):

Stress Transfer ◽

Single Fibre ◽

Transfer Model

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Stress-transfer model for the development of extension fracture boudinage

International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts ◽

10.1016/0148-9062(83)90033-5 ◽

1983 ◽

Vol 20 (5) ◽

pp. 137

Keyword(s):

Stress Transfer ◽

Transfer Model ◽

Extension Fracture

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Multiple Lines of Evidence for a Potentially Seismogenic Fault Along the Central-Apennine (Italy) Active Extensional Belt–An Unexpected Outcome of the MW6.5 Norcia 2016 Earthquake

Frontiers in Earth Science ◽

10.3389/feart.2021.642243 ◽

2021 ◽

Vol 9 ◽

Author(s):

Federica Ferrarini ◽

Rita de Nardis ◽

Francesco Brozzetti ◽

Daniele Cirillo ◽

J Ramón Arrowsmith ◽

...

Keyword(s):

Late Quaternary ◽

Tectonic Setting ◽

Central Italy ◽

Stress Transfer ◽

Normal Fault ◽

Normal Faults ◽

Coulomb Stress ◽

Seismic Sequence ◽

Seismogenic Fault ◽

Seismogenic Source

The Apenninic chain, in central Italy, has been recently struck by the Norcia 2016 seismic sequence. Three mainshocks, in 2016, occurred on August 24 (MW6.0), October 26 (MW 5.9) and October 30 (MW6.5) along well-known late Quaternary active WSW-dipping normal faults. Coseismic fractures and hypocentral seismicity distribution are mostly associated with failure along the Mt Vettore-Mt Bove (VBF) fault. Nevertheless, following the October 26 shock, the aftershock spatial distribution suggests the activation of a source not previously mapped beyond the northern tip of the VBF system. In this area, a remarkable seismicity rate was observed also during 2017 and 2018, the most energetic event being the April 10, 2018 (MW4.6) normal fault earthquake. In this paper, we advance the hypothesis that the Norcia seismic sequence activated a previously unknown seismogenic source. We constrain its geometry and seismogenic behavior by exploiting: 1) morphometric analysis of high-resolution topographic data; 2) field geologic- and morphotectonic evidence within the context of long-term deformation constraints; 3) 3D seismological validation of fault activity, and 4) Coulomb stress transfer modeling. Our results support the existence of distributed and subtle deformation along normal fault segments related to an immature structure, the Pievebovigliana fault (PBF). The fault strikes in NNW-SSE direction, dips to SW and is in right-lateral en echelon setting with the VBF system. Its activation has been highlighted by most of the seismicity observed in the sector. The geometry and location are compatible with volumes of enhanced stress identified by Coulomb stress-transfer computations. Its reconstructed length (at least 13 km) is compatible with the occurrence of MW≥6.0 earthquakes in a sector heretofore characterized by low seismic activity. The evidence for PBF is a new observation associated with the Norcia 2016 seismic sequence and is consistent with the overall tectonic setting of the area. Its existence implies a northward extent of the intra-Apennine extensional domain and should be considered to address seismic hazard assessments in central Italy.

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