Seismic Response Analysis of Historical Towns Rising on Rock Slabs Overlying a Clayey Substratum

Two case histories are presented which refer to the historical towns of Orvieto and Bisaccia, both located on top of rock buttes overlying a more deformable clayey substratum. The comparison of the two case histories indicates that apparently similar geological conditions do not lead to the same type of seismic response. In fact, the specific physical and dynamic properties of the substratum and the overlying slab can determine different seismic behaviour at the hill top and at the rock-clay interface. In particular, at Bisaccia a deamplification of the seismic motion at the hill top was predicted, as well as the development of excess pore pressures in the clay deposit underneath the conglomerate. On the other hand, at Orvieto significant amplification of surface motion is expected, due to the impedance contrast between the different pyroclastic materials of the rock slab and to the topography effect at the slab edge as well

Seismic Response Analysis of Historical Towns Rising on Rock Slabs Overlying a Clayey Substratum

Two case histories are presented which refer to the historical towns of Orvieto and Bisaccia, both located on top of rock buttes overlying a more deformable clayey substratum. The comparison of the two case histories indicates that apparently similar geological conditions do not lead to the same type of seismic response. In fact, the specific physical and dynamic properties of the substratum and the overlying slab can determine different seismic behaviour at the hill top and at the rock-clay interface. In particular, at Bisaccia a deamplification of the seismic motion at the hill top was predicted, as well as the development of excess pore pressures in the clay deposit underneath the conglomerate. On the other hand, at Orvieto significant amplification of surface motion is expected, due to the impedance contrast between the different pyroclastic materials of the rock slab and to the topography effect at the slab edge as well

Il ruolo degli effetti di sito sulla risposta strutturale degli edifici nella conca aquilana

Il terremoto de L’Aquila del 6 aprile 2009 è stato significativamente caratterizzato dagli effetti di sito, evidenziati sia dalla variabilità delle registrazioni accelerometriche in zona near fault che dalla disuniforme distribuzione del danno rilevato. In particolare, nel quartiere aquilano di Pettino, in corrispondenza di un complesso residenziale composto da sette edifici della stessa tipologia strutturale, è stato osservato un danneggiamento molto diversificato. La nota riporta i risultati di una serie di analisi di risposta sismica locale 1D, condotte in corrispondenza di alcuni degli edifici del quartiere, per i quali si disponeva di indagini geotecniche di dettaglio, finalizzate a valutare l’influenza degli effetti di sito sulla risposta delle strutture. I risultati delle analisi condotte in condizioni di campo libero hanno mostrato significative amplificazioni del moto proprio in corrispondenza delle frequenze fondamentali del moto di input. Le analisi del sistema sottosuolo-edificio, condotte mediante l’utilizzo di un codice con formulazione a masse concentrate hanno inoltre consentito di verificare l’incidenza dell’interazione inerziale sul moto in superficie, nonché di riprodurre in forma semplificata il meccanismo di piano soffice osservato

Development status of a Laue lens project for gamma-ray astronomy

We report the status of the HAXTEL project, devoted to perform a design study and the development of a Laue lens prototype. After a summary of the major results of the design study, the approach adopted to develop a Demonstration Model of a Laue lens is discussed, the set up described, and some results presented.Comment: 11 pages, 11 figures, 2007 SPIE Conference on Optics for EUV, X-Ray, and Gamma-Ray Astronomy II

Removing striping artifacts in light-sheet fluorescence microscopy: a review

In recent years, light-sheet fluorescence microscopy (LSFM) has found a broad application for imaging of diverse biological samples, ranging from sub-cellular structures to whole animals, both in-vivo and ex-vivo, owing to its many advantages relative to point-scanning methods. By providing the selective illumination of sample single planes, LSFM achieves an intrinsic optical sectioning and direct 2D image acquisition, with low out-of-focus fluorescence background, sample photo-damage and photo-bleaching. On the other hand, such an illumination scheme is prone to light absorption or scattering effects, which lead to uneven illumination and striping artifacts in the images, oriented along the light sheet propagation direction. Several methods have been developed to address this issue, ranging from fully optical solutions to entirely digital post-processing approaches. In this work, we present them, outlining their advantages, performance and limitations

Removing striping artifacts in light-sheet fluorescence microscopy: a review

In recent years, light-sheet fluorescence microscopy (LSFM) has found a broad application for imaging of diverse biological samples, ranging from sub-cellular structures to whole animals, both in-vivo and ex-vivo, owing to its many advantages relative to point-scanning methods. By providing the selective illumination of sample single planes, LSFM achieves an intrinsic optical sectioning and direct 2D image acquisition, with low out-of-focus fluorescence background, sample photo-damage and photo-bleaching. On the other hand, such an illumination scheme is prone to light absorption or scattering effects, which lead to uneven illumination and striping artifacts in the images, oriented along the light sheet propagation direction. Several methods have been developed to address this issue, ranging from fully optical solutions to entirely digital post-processing approaches. In this work, we present them, outlining their advantages, performance and limitations