Efficiency of Piles Stabilizing Slopes in Fine-Grained Soils

Equally spaced piles can be designed to ensure the stability of a slope with a desired safety factor or to restrain slow slope movements to prevent damage to existing structures. The piles are usually arranged in lines installed transversally to soil movements or in groups of limited extension in a plan according to their stabilizing or protective function. A numerical study has been performed to analyze the role of some design parameters in the efficiency of equally spaced piles, adopting two-dimensional (2D) and three-dimensional (3D) finite-difference (FD) models. Plane strain models have been used to study the soil arching mechanism and the associated stress transfer from the yielding soil to the stabilizing piles, while 3D numerical analyses have been performed to evaluate the efficiency of pile groups. The effect of varying pile spacing, pile embedded length, soil mechanical properties, and sloping ground conditions have been investigated for two-layer slopes assuming fixed or unconstrained piles. The outcomes of the parametric study made it possible to derive a simple analytical relationship to quantify the resisting contribution provided by the piles in an infinite slope. The paper shows that the proposed approach, even though limited to the ranges of the adopted parameters, can be used for a preliminary design of stabilizing piles to ensure the desired increase in the slope safety factor, as well as to achieve the desired reduction of downhill slope movements

La moderna Anestesia Generale:cenni storici e descrizione delle tecniche di applicazione più corrente

All'inizio sono brevemente elencati i primi passi della moderna anestesia in Italia e si parla poi del dualismo tra scuola Anglo -Americana e scuola Europea per le diverse tendenze nella scelta dei farmaci anestetici.Vengono poi esposte in maniera sintetica, le metodiche usate in epoca attuale

Variazione della glicemia dopo somministrazione e.v. diBenzodiazepine,di morfino-simili e durante chirurgia addominale in anestesia endovenosa bilanciata

Il comportamento della glicemia viene controllato in una serie di valutazioni sotto l'effetto delle benzodiazepine diverse e di farmaci morfinosimili somministrati via e.v. quindi durante interventi di colecistectomia

In tema di Autotrasfusione: salasso preoperatorio immediato ed emodiluizione moderata con Destrano 70.000

Dopo alcuni cenni storici relativi alla metodica vengono ricordati i vari tipi di tecniche in uso per realizzare l'autotrasfusione. La tecnica adottata dagli autori e realizzata in vari tipi di chirurgia, prevede un salasso preoperatorio immediato con emodiluizione moderata ottenuta con destrano 70.000; il sangue prelevato è stato sempre trasfuso durante o al termine degli intervent

Mitigation of tunneling effects via preinstalled barriers: the case of Line C of Rome underground

The city of Rome is upgrading its public transportation network with the construction of the 3rd underground railway line. The Line C of Rome underground crosses the historic city centre with significant interferences with existing monuments and buildings of historic value. As a consequence, protective measures are needed to prevent damage to the most sensitive structures. To test the efficiency of pre-installed barriers in reducing tunnelling effects, a line of bored piles was pre-installed in the stretch between Amba Aradam and San Giovanni stations, close to a well instrumented green-field section. This paper presents the monitoring data from both the green-field section and the section where the barrier was installed and compares the observed behaviour with that computed by finite element back-analyses performed using three approaches to simulate tunnel excavation

Transcutaneous ethanol injection in hepatocarcinoma: Problems in analgesia and sedation

Therapeutic ethanol injection into primitive or secondary hepatic tumours if performed in 'one shot' causes a great deal of pain. For this reason an analgesic/sedation protocol was devised. This relies on the administration of ketorolac-propofol-nitrogen oxide mixture that has been used to treat patients with neoplastic hepatic diseases. A 20 patient series is described. Analgesic protocol was very effective and the only drawbacks were a residual sleepiness than in part is probably dependent on ethanol emigration into the bloodstream and consequently to the central nervous system depression